drivers/regulator/core.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 //
   3 // core.c  --  Voltage/Current Regulator framework.
   4 //
   5 // Copyright 2007, 2008 Wolfson Microelectronics PLC.
   6 // Copyright 2008 SlimLogic Ltd.
   7 //
   8 // Author: Liam Girdwood <lrg@slimlogic.co.uk>
   9
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/debugfs.h>
  13 #include <linux/device.h>
  14 #include <linux/slab.h>
  15 #include <linux/async.h>
  16 #include <linux/err.h>
  17 #include <linux/mutex.h>
  18 #include <linux/suspend.h>
  19 #include <linux/delay.h>
  20 #include <linux/gpio/consumer.h>
  21 #include <linux/of.h>
  22 #include <linux/reboot.h>
  23 #include <linux/regmap.h>
  24 #include <linux/regulator/of_regulator.h>
  25 #include <linux/regulator/consumer.h>
  26 #include <linux/regulator/coupler.h>
  27 #include <linux/regulator/driver.h>
  28 #include <linux/regulator/machine.h>
  29 #include <linux/module.h>
  30
  31 #define CREATE_TRACE_POINTS
  32 #include <trace/events/regulator.h>
  33
  34 #include "dummy.h"
  35 #include "internal.h"
  36 #include "regnl.h"
  37
  38 static DEFINE_WW_CLASS(regulator_ww_class);
  39 static DEFINE_MUTEX(regulator_nesting_mutex);
  40 static DEFINE_MUTEX(regulator_list_mutex);
  41 static LIST_HEAD(regulator_map_list);
  42 static LIST_HEAD(regulator_ena_gpio_list);
  43 static LIST_HEAD(regulator_supply_alias_list);
  44 static LIST_HEAD(regulator_coupler_list);
  45 static bool has_full_constraints;
  46
  47 static struct dentry *debugfs_root;
  48
  49 /*
  50  * struct regulator_map
  51  *
  52  * Used to provide symbolic supply names to devices.
  53  */
  54 struct regulator_map {
  55         struct list_head list;
  56         const char *dev_name;   /* The dev_name() for the consumer */
  57         const char *supply;
  58         struct regulator_dev *regulator;
  59 };
  60
  61 /*
  62  * struct regulator_enable_gpio
  63  *
  64  * Management for shared enable GPIO pin
  65  */
  66 struct regulator_enable_gpio {
  67         struct list_head list;
  68         struct gpio_desc *gpiod;
  69         u32 enable_count;       /* a number of enabled shared GPIO */
  70         u32 request_count;      /* a number of requested shared GPIO */
  71 };
  72
  73 /*
  74  * struct regulator_supply_alias
  75  *
  76  * Used to map lookups for a supply onto an alternative device.
  77  */
  78 struct regulator_supply_alias {
  79         struct list_head list;
  80         struct device *src_dev;
  81         const char *src_supply;
  82         struct device *alias_dev;
  83         const char *alias_supply;
  84 };
  85
  86 static int _regulator_is_enabled(struct regulator_dev *rdev);
  87 static int _regulator_disable(struct regulator *regulator);
  88 static int _regulator_get_error_flags(struct regulator_dev *rdev, unsigned int *flags);
  89 static int _regulator_get_current_limit(struct regulator_dev *rdev);
  90 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
  91 static int _notifier_call_chain(struct regulator_dev *rdev,
  92                                   unsigned long event, void *data);
  93 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
  94                                      int min_uV, int max_uV);
  95 static int regulator_balance_voltage(struct regulator_dev *rdev,
  96                                      suspend_state_t state);
  97 static struct regulator *create_regulator(struct regulator_dev *rdev,
  98                                           struct device *dev,
  99                                           const char *supply_name);
 100 static void destroy_regulator(struct regulator *regulator);
 101 static void _regulator_put(struct regulator *regulator);
 102
 103 const char *rdev_get_name(struct regulator_dev *rdev)
 104 {
 105         if (rdev->constraints && rdev->constraints->name)
 106                 return rdev->constraints->name;
 107         else if (rdev->desc->name)
 108                 return rdev->desc->name;
 109         else
 110                 return "";
 111 }
 112 EXPORT_SYMBOL_GPL(rdev_get_name);
 113
 114 static bool have_full_constraints(void)
 115 {
 116         return has_full_constraints || of_have_populated_dt();
 117 }
 118
 119 static bool regulator_ops_is_valid(struct regulator_dev *rdev, int ops)
 120 {
 121         if (!rdev->constraints) {
 122                 rdev_err(rdev, "no constraints\n");
 123                 return false;
 124         }
 125
 126         if (rdev->constraints->valid_ops_mask & ops)
 127                 return true;
 128
 129         return false;
 130 }
 131
 132 /**
 133  * regulator_lock_nested - lock a single regulator
 134  * @rdev:               regulator source
 135  * @ww_ctx:             w/w mutex acquire context
 136  *
 137  * This function can be called many times by one task on
 138  * a single regulator and its mutex will be locked only
 139  * once. If a task, which is calling this function is other
 140  * than the one, which initially locked the mutex, it will
 141  * wait on mutex.
 142  */
 143 static inline int regulator_lock_nested(struct regulator_dev *rdev,
 144                                         struct ww_acquire_ctx *ww_ctx)
 145 {
 146         bool lock = false;
 147         int ret = 0;
 148
 149         mutex_lock(&regulator_nesting_mutex);
 150
 151         if (!ww_mutex_trylock(&rdev->mutex, ww_ctx)) {
 152                 if (rdev->mutex_owner == current)
 153                         rdev->ref_cnt++;
 154                 else
 155                         lock = true;
 156
 157                 if (lock) {
 158                         mutex_unlock(&regulator_nesting_mutex);
 159                         ret = ww_mutex_lock(&rdev->mutex, ww_ctx);
 160                         mutex_lock(&regulator_nesting_mutex);
 161                 }
 162         } else {
 163                 lock = true;
 164         }
 165
 166         if (lock && ret != -EDEADLK) {
 167                 rdev->ref_cnt++;
 168                 rdev->mutex_owner = current;
 169         }
 170
 171         mutex_unlock(&regulator_nesting_mutex);
 172
 173         return ret;
 174 }
 175
 176 /**
 177  * regulator_lock - lock a single regulator
 178  * @rdev:               regulator source
 179  *
 180  * This function can be called many times by one task on
 181  * a single regulator and its mutex will be locked only
 182  * once. If a task, which is calling this function is other
 183  * than the one, which initially locked the mutex, it will
 184  * wait on mutex.
 185  */
 186 static void regulator_lock(struct regulator_dev *rdev)
 187 {
 188         regulator_lock_nested(rdev, NULL);
 189 }
 190
 191 /**
 192  * regulator_unlock - unlock a single regulator
 193  * @rdev:               regulator_source
 194  *
 195  * This function unlocks the mutex when the
 196  * reference counter reaches 0.
 197  */
 198 static void regulator_unlock(struct regulator_dev *rdev)
 199 {
 200         mutex_lock(&regulator_nesting_mutex);
 201
 202         if (--rdev->ref_cnt == 0) {
 203                 rdev->mutex_owner = NULL;
 204                 ww_mutex_unlock(&rdev->mutex);
 205         }
 206
 207         WARN_ON_ONCE(rdev->ref_cnt < 0);
 208
 209         mutex_unlock(&regulator_nesting_mutex);
 210 }
 211
 212 /**
 213  * regulator_lock_two - lock two regulators
 214  * @rdev1:              first regulator
 215  * @rdev2:              second regulator
 216  * @ww_ctx:             w/w mutex acquire context
 217  *
 218  * Locks both rdevs using the regulator_ww_class.
 219  */
 220 static void regulator_lock_two(struct regulator_dev *rdev1,
 221                                struct regulator_dev *rdev2,
 222                                struct ww_acquire_ctx *ww_ctx)
 223 {
 224         struct regulator_dev *held, *contended;
 225         int ret;
 226
 227         ww_acquire_init(ww_ctx, &regulator_ww_class);
 228
 229         /* Try to just grab both of them */
 230         ret = regulator_lock_nested(rdev1, ww_ctx);
 231         WARN_ON(ret);
 232         ret = regulator_lock_nested(rdev2, ww_ctx);
 233         if (ret != -EDEADLOCK) {
 234                 WARN_ON(ret);
 235                 goto exit;
 236         }
 237
 238         held = rdev1;
 239         contended = rdev2;
 240         while (true) {
 241                 regulator_unlock(held);
 242
 243                 ww_mutex_lock_slow(&contended->mutex, ww_ctx);
 244                 contended->ref_cnt++;
 245                 contended->mutex_owner = current;
 246                 swap(held, contended);
 247                 ret = regulator_lock_nested(contended, ww_ctx);
 248
 249                 if (ret != -EDEADLOCK) {
 250                         WARN_ON(ret);
 251                         break;
 252                 }
 253         }
 254
 255 exit:
 256         ww_acquire_done(ww_ctx);
 257 }
 258
 259 /**
 260  * regulator_unlock_two - unlock two regulators
 261  * @rdev1:              first regulator
 262  * @rdev2:              second regulator
 263  * @ww_ctx:             w/w mutex acquire context
 264  *
 265  * The inverse of regulator_lock_two().
 266  */
 267
 268 static void regulator_unlock_two(struct regulator_dev *rdev1,
 269                                  struct regulator_dev *rdev2,
 270                                  struct ww_acquire_ctx *ww_ctx)
 271 {
 272         regulator_unlock(rdev2);
 273         regulator_unlock(rdev1);
 274         ww_acquire_fini(ww_ctx);
 275 }
 276
 277 static bool regulator_supply_is_couple(struct regulator_dev *rdev)
 278 {
 279         struct regulator_dev *c_rdev;
 280         int i;
 281
 282         for (i = 1; i < rdev->coupling_desc.n_coupled; i++) {
 283                 c_rdev = rdev->coupling_desc.coupled_rdevs[i];
 284
 285                 if (rdev->supply->rdev == c_rdev)
 286                         return true;
 287         }
 288
 289         return false;
 290 }
 291
 292 static void regulator_unlock_recursive(struct regulator_dev *rdev,
 293                                        unsigned int n_coupled)
 294 {
 295         struct regulator_dev *c_rdev, *supply_rdev;
 296         int i, supply_n_coupled;
 297
 298         for (i = n_coupled; i > 0; i--) {
 299                 c_rdev = rdev->coupling_desc.coupled_rdevs[i - 1];
 300
 301                 if (!c_rdev)
 302                         continue;
 303
 304                 if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
 305                         supply_rdev = c_rdev->supply->rdev;
 306                         supply_n_coupled = supply_rdev->coupling_desc.n_coupled;
 307
 308                         regulator_unlock_recursive(supply_rdev,
 309                                                    supply_n_coupled);
 310                 }
 311
 312                 regulator_unlock(c_rdev);
 313         }
 314 }
 315
 316 static int regulator_lock_recursive(struct regulator_dev *rdev,
 317                                     struct regulator_dev **new_contended_rdev,
 318                                     struct regulator_dev **old_contended_rdev,
 319                                     struct ww_acquire_ctx *ww_ctx)
 320 {
 321         struct regulator_dev *c_rdev;
 322         int i, err;
 323
 324         for (i = 0; i < rdev->coupling_desc.n_coupled; i++) {
 325                 c_rdev = rdev->coupling_desc.coupled_rdevs[i];
 326
 327                 if (!c_rdev)
 328                         continue;
 329
 330                 if (c_rdev != *old_contended_rdev) {
 331                         err = regulator_lock_nested(c_rdev, ww_ctx);
 332                         if (err) {
 333                                 if (err == -EDEADLK) {
 334                                         *new_contended_rdev = c_rdev;
 335                                         goto err_unlock;
 336                                 }
 337
 338                                 /* shouldn't happen */
 339                                 WARN_ON_ONCE(err != -EALREADY);
 340                         }
 341                 } else {
 342                         *old_contended_rdev = NULL;
 343                 }
 344
 345                 if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
 346                         err = regulator_lock_recursive(c_rdev->supply->rdev,
 347                                                        new_contended_rdev,
 348                                                        old_contended_rdev,
 349                                                        ww_ctx);
 350                         if (err) {
 351                                 regulator_unlock(c_rdev);
 352                                 goto err_unlock;
 353                         }
 354                 }
 355         }
 356
 357         return 0;
 358
 359 err_unlock:
 360         regulator_unlock_recursive(rdev, i);
 361
 362         return err;
 363 }
 364
 365 /**
 366  * regulator_unlock_dependent - unlock regulator's suppliers and coupled
 367  *                              regulators
 368  * @rdev:                       regulator source
 369  * @ww_ctx:                     w/w mutex acquire context
 370  *
 371  * Unlock all regulators related with rdev by coupling or supplying.
 372  */
 373 static void regulator_unlock_dependent(struct regulator_dev *rdev,
 374                                        struct ww_acquire_ctx *ww_ctx)
 375 {
 376         regulator_unlock_recursive(rdev, rdev->coupling_desc.n_coupled);
 377         ww_acquire_fini(ww_ctx);
 378 }
 379
 380 /**
 381  * regulator_lock_dependent - lock regulator's suppliers and coupled regulators
 382  * @rdev:                       regulator source
 383  * @ww_ctx:                     w/w mutex acquire context
 384  *
 385  * This function as a wrapper on regulator_lock_recursive(), which locks
 386  * all regulators related with rdev by coupling or supplying.
 387  */
 388 static void regulator_lock_dependent(struct regulator_dev *rdev,
 389                                      struct ww_acquire_ctx *ww_ctx)
 390 {
 391         struct regulator_dev *new_contended_rdev = NULL;
 392         struct regulator_dev *old_contended_rdev = NULL;
 393         int err;
 394
 395         mutex_lock(&regulator_list_mutex);
 396
 397         ww_acquire_init(ww_ctx, &regulator_ww_class);
 398
 399         do {
 400                 if (new_contended_rdev) {
 401                         ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
 402                         old_contended_rdev = new_contended_rdev;
 403                         old_contended_rdev->ref_cnt++;
 404                         old_contended_rdev->mutex_owner = current;
 405                 }
 406
 407                 err = regulator_lock_recursive(rdev,
 408                                                &new_contended_rdev,
 409                                                &old_contended_rdev,
 410                                                ww_ctx);
 411
 412                 if (old_contended_rdev)
 413                         regulator_unlock(old_contended_rdev);
 414
 415         } while (err == -EDEADLK);
 416
 417         ww_acquire_done(ww_ctx);
 418
 419         mutex_unlock(&regulator_list_mutex);
 420 }
 421
 422 /**
 423  * of_get_child_regulator - get a child regulator device node
 424  * based on supply name
 425  * @parent: Parent device node
 426  * @prop_name: Combination regulator supply name and "-supply"
 427  *
 428  * Traverse all child nodes.
 429  * Extract the child regulator device node corresponding to the supply name.
 430  * returns the device node corresponding to the regulator if found, else
 431  * returns NULL.
 432  */
 433 static struct device_node *of_get_child_regulator(struct device_node *parent,
 434                                                   const char *prop_name)
 435 {
 436         struct device_node *regnode = NULL;
 437         struct device_node *child = NULL;
 438
 439         for_each_child_of_node(parent, child) {
 440                 regnode = of_parse_phandle(child, prop_name, 0);
 441
 442                 if (!regnode) {
 443                         regnode = of_get_child_regulator(child, prop_name);
 444                         if (regnode)
 445                                 goto err_node_put;
 446                 } else {
 447                         goto err_node_put;
 448                 }
 449         }
 450         return NULL;
 451
 452 err_node_put:
 453         of_node_put(child);
 454         return regnode;
 455 }
 456
 457 /**
 458  * of_get_regulator - get a regulator device node based on supply name
 459  * @dev: Device pointer for the consumer (of regulator) device
 460  * @supply: regulator supply name
 461  *
 462  * Extract the regulator device node corresponding to the supply name.
 463  * returns the device node corresponding to the regulator if found, else
 464  * returns NULL.
 465  */
 466 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
 467 {
 468         struct device_node *regnode = NULL;
 469         char prop_name[64]; /* 64 is max size of property name */
 470
 471         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
 472
 473         snprintf(prop_name, 64, "%s-supply", supply);
 474         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
 475
 476         if (!regnode) {
 477                 regnode = of_get_child_regulator(dev->of_node, prop_name);
 478                 if (regnode)
 479                         return regnode;
 480
 481                 dev_dbg(dev, "Looking up %s property in node %pOF failed\n",
 482                                 prop_name, dev->of_node);
 483                 return NULL;
 484         }
 485         return regnode;
 486 }
 487
 488 /* Platform voltage constraint check */
 489 int regulator_check_voltage(struct regulator_dev *rdev,
 490                             int *min_uV, int *max_uV)
 491 {
 492         BUG_ON(*min_uV > *max_uV);
 493
 494         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
 495                 rdev_err(rdev, "voltage operation not allowed\n");
 496                 return -EPERM;
 497         }
 498
 499         if (*max_uV > rdev->constraints->max_uV)
 500                 *max_uV = rdev->constraints->max_uV;
 501         if (*min_uV < rdev->constraints->min_uV)
 502                 *min_uV = rdev->constraints->min_uV;
 503
 504         if (*min_uV > *max_uV) {
 505                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
 506                          *min_uV, *max_uV);
 507                 return -EINVAL;
 508         }
 509
 510         return 0;
 511 }
 512
 513 /* return 0 if the state is valid */
 514 static int regulator_check_states(suspend_state_t state)
 515 {
 516         return (state > PM_SUSPEND_MAX || state == PM_SUSPEND_TO_IDLE);
 517 }
 518
 519 /* Make sure we select a voltage that suits the needs of all
 520  * regulator consumers
 521  */
 522 int regulator_check_consumers(struct regulator_dev *rdev,
 523                               int *min_uV, int *max_uV,
 524                               suspend_state_t state)
 525 {
 526         struct regulator *regulator;
 527         struct regulator_voltage *voltage;
 528
 529         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 530                 voltage = &regulator->voltage[state];
 531                 /*
 532                  * Assume consumers that didn't say anything are OK
 533                  * with anything in the constraint range.
 534                  */
 535                 if (!voltage->min_uV && !voltage->max_uV)
 536                         continue;
 537
 538                 if (*max_uV > voltage->max_uV)
 539                         *max_uV = voltage->max_uV;
 540                 if (*min_uV < voltage->min_uV)
 541                         *min_uV = voltage->min_uV;
 542         }
 543
 544         if (*min_uV > *max_uV) {
 545                 rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
 546                         *min_uV, *max_uV);
 547                 return -EINVAL;
 548         }
 549
 550         return 0;
 551 }
 552
 553 /* current constraint check */
 554 static int regulator_check_current_limit(struct regulator_dev *rdev,
 555                                         int *min_uA, int *max_uA)
 556 {
 557         BUG_ON(*min_uA > *max_uA);
 558
 559         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_CURRENT)) {
 560                 rdev_err(rdev, "current operation not allowed\n");
 561                 return -EPERM;
 562         }
 563
 564         if (*max_uA > rdev->constraints->max_uA)
 565                 *max_uA = rdev->constraints->max_uA;
 566         if (*min_uA < rdev->constraints->min_uA)
 567                 *min_uA = rdev->constraints->min_uA;
 568
 569         if (*min_uA > *max_uA) {
 570                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
 571                          *min_uA, *max_uA);
 572                 return -EINVAL;
 573         }
 574
 575         return 0;
 576 }
 577
 578 /* operating mode constraint check */
 579 static int regulator_mode_constrain(struct regulator_dev *rdev,
 580                                     unsigned int *mode)
 581 {
 582         switch (*mode) {
 583         case REGULATOR_MODE_FAST:
 584         case REGULATOR_MODE_NORMAL:
 585         case REGULATOR_MODE_IDLE:
 586         case REGULATOR_MODE_STANDBY:
 587                 break;
 588         default:
 589                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
 590                 return -EINVAL;
 591         }
 592
 593         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_MODE)) {
 594                 rdev_err(rdev, "mode operation not allowed\n");
 595                 return -EPERM;
 596         }
 597
 598         /* The modes are bitmasks, the most power hungry modes having
 599          * the lowest values. If the requested mode isn't supported
 600          * try higher modes.
 601          */
 602         while (*mode) {
 603                 if (rdev->constraints->valid_modes_mask & *mode)
 604                         return 0;
 605                 *mode /= 2;
 606         }
 607
 608         return -EINVAL;
 609 }
 610
 611 static inline struct regulator_state *
 612 regulator_get_suspend_state(struct regulator_dev *rdev, suspend_state_t state)
 613 {
 614         if (rdev->constraints == NULL)
 615                 return NULL;
 616
 617         switch (state) {
 618         case PM_SUSPEND_STANDBY:
 619                 return &rdev->constraints->state_standby;
 620         case PM_SUSPEND_MEM:
 621                 return &rdev->constraints->state_mem;
 622         case PM_SUSPEND_MAX:
 623                 return &rdev->constraints->state_disk;
 624         default:
 625                 return NULL;
 626         }
 627 }
 628
 629 static const struct regulator_state *
 630 regulator_get_suspend_state_check(struct regulator_dev *rdev, suspend_state_t state)
 631 {
 632         const struct regulator_state *rstate;
 633
 634         rstate = regulator_get_suspend_state(rdev, state);
 635         if (rstate == NULL)
 636                 return NULL;
 637
 638         /* If we have no suspend mode configuration don't set anything;
 639          * only warn if the driver implements set_suspend_voltage or
 640          * set_suspend_mode callback.
 641          */
 642         if (rstate->enabled != ENABLE_IN_SUSPEND &&
 643             rstate->enabled != DISABLE_IN_SUSPEND) {
 644                 if (rdev->desc->ops->set_suspend_voltage ||
 645                     rdev->desc->ops->set_suspend_mode)
 646                         rdev_warn(rdev, "No configuration\n");
 647                 return NULL;
 648         }
 649
 650         return rstate;
 651 }
 652
 653 static ssize_t microvolts_show(struct device *dev,
 654                                struct device_attribute *attr, char *buf)
 655 {
 656         struct regulator_dev *rdev = dev_get_drvdata(dev);
 657         int uV;
 658
 659         regulator_lock(rdev);
 660         uV = regulator_get_voltage_rdev(rdev);
 661         regulator_unlock(rdev);
 662
 663         if (uV < 0)
 664                 return uV;
 665         return sprintf(buf, "%d\n", uV);
 666 }
 667 static DEVICE_ATTR_RO(microvolts);
 668
 669 static ssize_t microamps_show(struct device *dev,
 670                               struct device_attribute *attr, char *buf)
 671 {
 672         struct regulator_dev *rdev = dev_get_drvdata(dev);
 673
 674         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 675 }
 676 static DEVICE_ATTR_RO(microamps);
 677
 678 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 679                          char *buf)
 680 {
 681         struct regulator_dev *rdev = dev_get_drvdata(dev);
 682
 683         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 684 }
 685 static DEVICE_ATTR_RO(name);
 686
 687 static const char *regulator_opmode_to_str(int mode)
 688 {
 689         switch (mode) {
 690         case REGULATOR_MODE_FAST:
 691                 return "fast";
 692         case REGULATOR_MODE_NORMAL:
 693                 return "normal";
 694         case REGULATOR_MODE_IDLE:
 695                 return "idle";
 696         case REGULATOR_MODE_STANDBY:
 697                 return "standby";
 698         }
 699         return "unknown";
 700 }
 701
 702 static ssize_t regulator_print_opmode(char *buf, int mode)
 703 {
 704         return sprintf(buf, "%s\n", regulator_opmode_to_str(mode));
 705 }
 706
 707 static ssize_t opmode_show(struct device *dev,
 708                            struct device_attribute *attr, char *buf)
 709 {
 710         struct regulator_dev *rdev = dev_get_drvdata(dev);
 711
 712         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 713 }
 714 static DEVICE_ATTR_RO(opmode);
 715
 716 static ssize_t regulator_print_state(char *buf, int state)
 717 {
 718         if (state > 0)
 719                 return sprintf(buf, "enabled\n");
 720         else if (state == 0)
 721                 return sprintf(buf, "disabled\n");
 722         else
 723                 return sprintf(buf, "unknown\n");
 724 }
 725
 726 static ssize_t state_show(struct device *dev,
 727                           struct device_attribute *attr, char *buf)
 728 {
 729         struct regulator_dev *rdev = dev_get_drvdata(dev);
 730         ssize_t ret;
 731
 732         regulator_lock(rdev);
 733         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 734         regulator_unlock(rdev);
 735
 736         return ret;
 737 }
 738 static DEVICE_ATTR_RO(state);
 739
 740 static ssize_t status_show(struct device *dev,
 741                            struct device_attribute *attr, char *buf)
 742 {
 743         struct regulator_dev *rdev = dev_get_drvdata(dev);
 744         int status;
 745         char *label;
 746
 747         status = rdev->desc->ops->get_status(rdev);
 748         if (status < 0)
 749                 return status;
 750
 751         switch (status) {
 752         case REGULATOR_STATUS_OFF:
 753                 label = "off";
 754                 break;
 755         case REGULATOR_STATUS_ON:
 756                 label = "on";
 757                 break;
 758         case REGULATOR_STATUS_ERROR:
 759                 label = "error";
 760                 break;
 761         case REGULATOR_STATUS_FAST:
 762                 label = "fast";
 763                 break;
 764         case REGULATOR_STATUS_NORMAL:
 765                 label = "normal";
 766                 break;
 767         case REGULATOR_STATUS_IDLE:
 768                 label = "idle";
 769                 break;
 770         case REGULATOR_STATUS_STANDBY:
 771                 label = "standby";
 772                 break;
 773         case REGULATOR_STATUS_BYPASS:
 774                 label = "bypass";
 775                 break;
 776         case REGULATOR_STATUS_UNDEFINED:
 777                 label = "undefined";
 778                 break;
 779         default:
 780                 return -ERANGE;
 781         }
 782
 783         return sprintf(buf, "%s\n", label);
 784 }
 785 static DEVICE_ATTR_RO(status);
 786
 787 static ssize_t min_microamps_show(struct device *dev,
 788                                   struct device_attribute *attr, char *buf)
 789 {
 790         struct regulator_dev *rdev = dev_get_drvdata(dev);
 791
 792         if (!rdev->constraints)
 793                 return sprintf(buf, "constraint not defined\n");
 794
 795         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 796 }
 797 static DEVICE_ATTR_RO(min_microamps);
 798
 799 static ssize_t max_microamps_show(struct device *dev,
 800                                   struct device_attribute *attr, char *buf)
 801 {
 802         struct regulator_dev *rdev = dev_get_drvdata(dev);
 803
 804         if (!rdev->constraints)
 805                 return sprintf(buf, "constraint not defined\n");
 806
 807         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 808 }
 809 static DEVICE_ATTR_RO(max_microamps);
 810
 811 static ssize_t min_microvolts_show(struct device *dev,
 812                                    struct device_attribute *attr, char *buf)
 813 {
 814         struct regulator_dev *rdev = dev_get_drvdata(dev);
 815
 816         if (!rdev->constraints)
 817                 return sprintf(buf, "constraint not defined\n");
 818
 819         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 820 }
 821 static DEVICE_ATTR_RO(min_microvolts);
 822
 823 static ssize_t max_microvolts_show(struct device *dev,
 824                                    struct device_attribute *attr, char *buf)
 825 {
 826         struct regulator_dev *rdev = dev_get_drvdata(dev);
 827
 828         if (!rdev->constraints)
 829                 return sprintf(buf, "constraint not defined\n");
 830
 831         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 832 }
 833 static DEVICE_ATTR_RO(max_microvolts);
 834
 835 static ssize_t requested_microamps_show(struct device *dev,
 836                                         struct device_attribute *attr, char *buf)
 837 {
 838         struct regulator_dev *rdev = dev_get_drvdata(dev);
 839         struct regulator *regulator;
 840         int uA = 0;
 841
 842         regulator_lock(rdev);
 843         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 844                 if (regulator->enable_count)
 845                         uA += regulator->uA_load;
 846         }
 847         regulator_unlock(rdev);
 848         return sprintf(buf, "%d\n", uA);
 849 }
 850 static DEVICE_ATTR_RO(requested_microamps);
 851
 852 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
 853                               char *buf)
 854 {
 855         struct regulator_dev *rdev = dev_get_drvdata(dev);
 856         return sprintf(buf, "%d\n", rdev->use_count);
 857 }
 858 static DEVICE_ATTR_RO(num_users);
 859
 860 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 861                          char *buf)
 862 {
 863         struct regulator_dev *rdev = dev_get_drvdata(dev);
 864
 865         switch (rdev->desc->type) {
 866         case REGULATOR_VOLTAGE:
 867                 return sprintf(buf, "voltage\n");
 868         case REGULATOR_CURRENT:
 869                 return sprintf(buf, "current\n");
 870         }
 871         return sprintf(buf, "unknown\n");
 872 }
 873 static DEVICE_ATTR_RO(type);
 874
 875 static ssize_t suspend_mem_microvolts_show(struct device *dev,
 876                                            struct device_attribute *attr, char *buf)
 877 {
 878         struct regulator_dev *rdev = dev_get_drvdata(dev);
 879
 880         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 881 }
 882 static DEVICE_ATTR_RO(suspend_mem_microvolts);
 883
 884 static ssize_t suspend_disk_microvolts_show(struct device *dev,
 885                                             struct device_attribute *attr, char *buf)
 886 {
 887         struct regulator_dev *rdev = dev_get_drvdata(dev);
 888
 889         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 890 }
 891 static DEVICE_ATTR_RO(suspend_disk_microvolts);
 892
 893 static ssize_t suspend_standby_microvolts_show(struct device *dev,
 894                                                struct device_attribute *attr, char *buf)
 895 {
 896         struct regulator_dev *rdev = dev_get_drvdata(dev);
 897
 898         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 899 }
 900 static DEVICE_ATTR_RO(suspend_standby_microvolts);
 901
 902 static ssize_t suspend_mem_mode_show(struct device *dev,
 903                                      struct device_attribute *attr, char *buf)
 904 {
 905         struct regulator_dev *rdev = dev_get_drvdata(dev);
 906
 907         return regulator_print_opmode(buf,
 908                 rdev->constraints->state_mem.mode);
 909 }
 910 static DEVICE_ATTR_RO(suspend_mem_mode);
 911
 912 static ssize_t suspend_disk_mode_show(struct device *dev,
 913                                       struct device_attribute *attr, char *buf)
 914 {
 915         struct regulator_dev *rdev = dev_get_drvdata(dev);
 916
 917         return regulator_print_opmode(buf,
 918                 rdev->constraints->state_disk.mode);
 919 }
 920 static DEVICE_ATTR_RO(suspend_disk_mode);
 921
 922 static ssize_t suspend_standby_mode_show(struct device *dev,
 923                                          struct device_attribute *attr, char *buf)
 924 {
 925         struct regulator_dev *rdev = dev_get_drvdata(dev);
 926
 927         return regulator_print_opmode(buf,
 928                 rdev->constraints->state_standby.mode);
 929 }
 930 static DEVICE_ATTR_RO(suspend_standby_mode);
 931
 932 static ssize_t suspend_mem_state_show(struct device *dev,
 933                                       struct device_attribute *attr, char *buf)
 934 {
 935         struct regulator_dev *rdev = dev_get_drvdata(dev);
 936
 937         return regulator_print_state(buf,
 938                         rdev->constraints->state_mem.enabled);
 939 }
 940 static DEVICE_ATTR_RO(suspend_mem_state);
 941
 942 static ssize_t suspend_disk_state_show(struct device *dev,
 943                                        struct device_attribute *attr, char *buf)
 944 {
 945         struct regulator_dev *rdev = dev_get_drvdata(dev);
 946
 947         return regulator_print_state(buf,
 948                         rdev->constraints->state_disk.enabled);
 949 }
 950 static DEVICE_ATTR_RO(suspend_disk_state);
 951
 952 static ssize_t suspend_standby_state_show(struct device *dev,
 953                                           struct device_attribute *attr, char *buf)
 954 {
 955         struct regulator_dev *rdev = dev_get_drvdata(dev);
 956
 957         return regulator_print_state(buf,
 958                         rdev->constraints->state_standby.enabled);
 959 }
 960 static DEVICE_ATTR_RO(suspend_standby_state);
 961
 962 static ssize_t bypass_show(struct device *dev,
 963                            struct device_attribute *attr, char *buf)
 964 {
 965         struct regulator_dev *rdev = dev_get_drvdata(dev);
 966         const char *report;
 967         bool bypass;
 968         int ret;
 969
 970         ret = rdev->desc->ops->get_bypass(rdev, &bypass);
 971
 972         if (ret != 0)
 973                 report = "unknown";
 974         else if (bypass)
 975                 report = "enabled";
 976         else
 977                 report = "disabled";
 978
 979         return sprintf(buf, "%s\n", report);
 980 }
 981 static DEVICE_ATTR_RO(bypass);
 982
 983 #define REGULATOR_ERROR_ATTR(name, bit)                                                 \
 984         static ssize_t name##_show(struct device *dev, struct device_attribute *attr,   \
 985                                    char *buf)                                           \
 986         {                                                                               \
 987                 int ret;                                                                \
 988                 unsigned int flags;                                                     \
 989                 struct regulator_dev *rdev = dev_get_drvdata(dev);                      \
 990                 ret = _regulator_get_error_flags(rdev, &flags);                         \
 991                 if (ret)                                                                \
 992                         return ret;                                                     \
 993                 return sysfs_emit(buf, "%d\n", !!(flags & (bit)));                      \
 994         }                                                                               \
 995         static DEVICE_ATTR_RO(name)
 996
 997 REGULATOR_ERROR_ATTR(under_voltage, REGULATOR_ERROR_UNDER_VOLTAGE);
 998 REGULATOR_ERROR_ATTR(over_current, REGULATOR_ERROR_OVER_CURRENT);
 999 REGULATOR_ERROR_ATTR(regulation_out, REGULATOR_ERROR_REGULATION_OUT);
1000 REGULATOR_ERROR_ATTR(fail, REGULATOR_ERROR_FAIL);
1001 REGULATOR_ERROR_ATTR(over_temp, REGULATOR_ERROR_OVER_TEMP);
1002 REGULATOR_ERROR_ATTR(under_voltage_warn, REGULATOR_ERROR_UNDER_VOLTAGE_WARN);
1003 REGULATOR_ERROR_ATTR(over_current_warn, REGULATOR_ERROR_OVER_CURRENT_WARN);
1004 REGULATOR_ERROR_ATTR(over_voltage_warn, REGULATOR_ERROR_OVER_VOLTAGE_WARN);
1005 REGULATOR_ERROR_ATTR(over_temp_warn, REGULATOR_ERROR_OVER_TEMP_WARN);
1006
1007 /* Calculate the new optimum regulator operating mode based on the new total
1008  * consumer load. All locks held by caller
1009  */
1010 static int drms_uA_update(struct regulator_dev *rdev)
1011 {
1012         struct regulator *sibling;
1013         int current_uA = 0, output_uV, input_uV, err;
1014         unsigned int mode;
1015
1016         /*
1017          * first check to see if we can set modes at all, otherwise just
1018          * tell the consumer everything is OK.
1019          */
1020         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_DRMS)) {
1021                 rdev_dbg(rdev, "DRMS operation not allowed\n");
1022                 return 0;
1023         }
1024
1025         if (!rdev->desc->ops->get_optimum_mode &&
1026             !rdev->desc->ops->set_load)
1027                 return 0;
1028
1029         if (!rdev->desc->ops->set_mode &&
1030             !rdev->desc->ops->set_load)
1031                 return -EINVAL;
1032
1033         /* calc total requested load */
1034         list_for_each_entry(sibling, &rdev->consumer_list, list) {
1035                 if (sibling->enable_count)
1036                         current_uA += sibling->uA_load;
1037         }
1038
1039         current_uA += rdev->constraints->system_load;
1040
1041         if (rdev->desc->ops->set_load) {
1042                 /* set the optimum mode for our new total regulator load */
1043                 err = rdev->desc->ops->set_load(rdev, current_uA);
1044                 if (err < 0)
1045                         rdev_err(rdev, "failed to set load %d: %pe\n",
1046                                  current_uA, ERR_PTR(err));
1047         } else {
1048                 /*
1049                  * Unfortunately in some cases the constraints->valid_ops has
1050                  * REGULATOR_CHANGE_DRMS but there are no valid modes listed.
1051                  * That's not really legit but we won't consider it a fatal
1052                  * error here. We'll treat it as if REGULATOR_CHANGE_DRMS
1053                  * wasn't set.
1054                  */
1055                 if (!rdev->constraints->valid_modes_mask) {
1056                         rdev_dbg(rdev, "Can change modes; but no valid mode\n");
1057                         return 0;
1058                 }
1059
1060                 /* get output voltage */
1061                 output_uV = regulator_get_voltage_rdev(rdev);
1062
1063                 /*
1064                  * Don't return an error; if regulator driver cares about
1065                  * output_uV then it's up to the driver to validate.
1066                  */
1067                 if (output_uV <= 0)
1068                         rdev_dbg(rdev, "invalid output voltage found\n");
1069
1070                 /* get input voltage */
1071                 input_uV = 0;
1072                 if (rdev->supply)
1073                         input_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
1074                 if (input_uV <= 0)
1075                         input_uV = rdev->constraints->input_uV;
1076
1077                 /*
1078                  * Don't return an error; if regulator driver cares about
1079                  * input_uV then it's up to the driver to validate.
1080                  */
1081                 if (input_uV <= 0)
1082                         rdev_dbg(rdev, "invalid input voltage found\n");
1083
1084                 /* now get the optimum mode for our new total regulator load */
1085                 mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
1086                                                          output_uV, current_uA);
1087
1088                 /* check the new mode is allowed */
1089                 err = regulator_mode_constrain(rdev, &mode);
1090                 if (err < 0) {
1091                         rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV: %pe\n",
1092                                  current_uA, input_uV, output_uV, ERR_PTR(err));
1093                         return err;
1094                 }
1095
1096                 err = rdev->desc->ops->set_mode(rdev, mode);
1097                 if (err < 0)
1098                         rdev_err(rdev, "failed to set optimum mode %x: %pe\n",
1099                                  mode, ERR_PTR(err));
1100         }
1101
1102         return err;
1103 }
1104
1105 static int __suspend_set_state(struct regulator_dev *rdev,
1106                                const struct regulator_state *rstate)
1107 {
1108         int ret = 0;
1109
1110         if (rstate->enabled == ENABLE_IN_SUSPEND &&
1111                 rdev->desc->ops->set_suspend_enable)
1112                 ret = rdev->desc->ops->set_suspend_enable(rdev);
1113         else if (rstate->enabled == DISABLE_IN_SUSPEND &&
1114                 rdev->desc->ops->set_suspend_disable)
1115                 ret = rdev->desc->ops->set_suspend_disable(rdev);
1116         else /* OK if set_suspend_enable or set_suspend_disable is NULL */
1117                 ret = 0;
1118
1119         if (ret < 0) {
1120                 rdev_err(rdev, "failed to enabled/disable: %pe\n", ERR_PTR(ret));
1121                 return ret;
1122         }
1123
1124         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
1125                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
1126                 if (ret < 0) {
1127                         rdev_err(rdev, "failed to set voltage: %pe\n", ERR_PTR(ret));
1128                         return ret;
1129                 }
1130         }
1131
1132         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
1133                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
1134                 if (ret < 0) {
1135                         rdev_err(rdev, "failed to set mode: %pe\n", ERR_PTR(ret));
1136                         return ret;
1137                 }
1138         }
1139
1140         return ret;
1141 }
1142
1143 static int suspend_set_initial_state(struct regulator_dev *rdev)
1144 {
1145         const struct regulator_state *rstate;
1146
1147         rstate = regulator_get_suspend_state_check(rdev,
1148                         rdev->constraints->initial_state);
1149         if (!rstate)
1150                 return 0;
1151
1152         return __suspend_set_state(rdev, rstate);
1153 }
1154
1155 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
1156 static void print_constraints_debug(struct regulator_dev *rdev)
1157 {
1158         struct regulation_constraints *constraints = rdev->constraints;
1159         char buf[160] = "";
1160         size_t len = sizeof(buf) - 1;
1161         int count = 0;
1162         int ret;
1163
1164         if (constraints->min_uV && constraints->max_uV) {
1165                 if (constraints->min_uV == constraints->max_uV)
1166                         count += scnprintf(buf + count, len - count, "%d mV ",
1167                                            constraints->min_uV / 1000);
1168                 else
1169                         count += scnprintf(buf + count, len - count,
1170                                            "%d <--> %d mV ",
1171                                            constraints->min_uV / 1000,
1172                                            constraints->max_uV / 1000);
1173         }
1174
1175         if (!constraints->min_uV ||
1176             constraints->min_uV != constraints->max_uV) {
1177                 ret = regulator_get_voltage_rdev(rdev);
1178                 if (ret > 0)
1179                         count += scnprintf(buf + count, len - count,
1180                                            "at %d mV ", ret / 1000);
1181         }
1182
1183         if (constraints->uV_offset)
1184                 count += scnprintf(buf + count, len - count, "%dmV offset ",
1185                                    constraints->uV_offset / 1000);
1186
1187         if (constraints->min_uA && constraints->max_uA) {
1188                 if (constraints->min_uA == constraints->max_uA)
1189                         count += scnprintf(buf + count, len - count, "%d mA ",
1190                                            constraints->min_uA / 1000);
1191                 else
1192                         count += scnprintf(buf + count, len - count,
1193                                            "%d <--> %d mA ",
1194                                            constraints->min_uA / 1000,
1195                                            constraints->max_uA / 1000);
1196         }
1197
1198         if (!constraints->min_uA ||
1199             constraints->min_uA != constraints->max_uA) {
1200                 ret = _regulator_get_current_limit(rdev);
1201                 if (ret > 0)
1202                         count += scnprintf(buf + count, len - count,
1203                                            "at %d mA ", ret / 1000);
1204         }
1205
1206         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
1207                 count += scnprintf(buf + count, len - count, "fast ");
1208         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
1209                 count += scnprintf(buf + count, len - count, "normal ");
1210         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
1211                 count += scnprintf(buf + count, len - count, "idle ");
1212         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
1213                 count += scnprintf(buf + count, len - count, "standby ");
1214
1215         if (!count)
1216                 count = scnprintf(buf, len, "no parameters");
1217         else
1218                 --count;
1219
1220         count += scnprintf(buf + count, len - count, ", %s",
1221                 _regulator_is_enabled(rdev) ? "enabled" : "disabled");
1222
1223         rdev_dbg(rdev, "%s\n", buf);
1224 }
1225 #else /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1226 static inline void print_constraints_debug(struct regulator_dev *rdev) {}
1227 #endif /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1228
1229 static void print_constraints(struct regulator_dev *rdev)
1230 {
1231         struct regulation_constraints *constraints = rdev->constraints;
1232
1233         print_constraints_debug(rdev);
1234
1235         if ((constraints->min_uV != constraints->max_uV) &&
1236             !regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
1237                 rdev_warn(rdev,
1238                           "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
1239 }
1240
1241 static int machine_constraints_voltage(struct regulator_dev *rdev,
1242         struct regulation_constraints *constraints)
1243 {
1244         const struct regulator_ops *ops = rdev->desc->ops;
1245         int ret;
1246
1247         /* do we need to apply the constraint voltage */
1248         if (rdev->constraints->apply_uV &&
1249             rdev->constraints->min_uV && rdev->constraints->max_uV) {
1250                 int target_min, target_max;
1251                 int current_uV = regulator_get_voltage_rdev(rdev);
1252
1253                 if (current_uV == -ENOTRECOVERABLE) {
1254                         /* This regulator can't be read and must be initialized */
1255                         rdev_info(rdev, "Setting %d-%duV\n",
1256                                   rdev->constraints->min_uV,
1257                                   rdev->constraints->max_uV);
1258                         _regulator_do_set_voltage(rdev,
1259                                                   rdev->constraints->min_uV,
1260                                                   rdev->constraints->max_uV);
1261                         current_uV = regulator_get_voltage_rdev(rdev);
1262                 }
1263
1264                 if (current_uV < 0) {
1265                         if (current_uV != -EPROBE_DEFER)
1266                                 rdev_err(rdev,
1267                                          "failed to get the current voltage: %pe\n",
1268                                          ERR_PTR(current_uV));
1269                         return current_uV;
1270                 }
1271
1272                 /*
1273                  * If we're below the minimum voltage move up to the
1274                  * minimum voltage, if we're above the maximum voltage
1275                  * then move down to the maximum.
1276                  */
1277                 target_min = current_uV;
1278                 target_max = current_uV;
1279
1280                 if (current_uV < rdev->constraints->min_uV) {
1281                         target_min = rdev->constraints->min_uV;
1282                         target_max = rdev->constraints->min_uV;
1283                 }
1284
1285                 if (current_uV > rdev->constraints->max_uV) {
1286                         target_min = rdev->constraints->max_uV;
1287                         target_max = rdev->constraints->max_uV;
1288                 }
1289
1290                 if (target_min != current_uV || target_max != current_uV) {
1291                         rdev_info(rdev, "Bringing %duV into %d-%duV\n",
1292                                   current_uV, target_min, target_max);
1293                         ret = _regulator_do_set_voltage(
1294                                 rdev, target_min, target_max);
1295                         if (ret < 0) {
1296                                 rdev_err(rdev,
1297                                         "failed to apply %d-%duV constraint: %pe\n",
1298                                         target_min, target_max, ERR_PTR(ret));
1299                                 return ret;
1300                         }
1301                 }
1302         }
1303
1304         /* constrain machine-level voltage specs to fit
1305          * the actual range supported by this regulator.
1306          */
1307         if (ops->list_voltage && rdev->desc->n_voltages) {
1308                 int     count = rdev->desc->n_voltages;
1309                 int     i;
1310                 int     min_uV = INT_MAX;
1311                 int     max_uV = INT_MIN;
1312                 int     cmin = constraints->min_uV;
1313                 int     cmax = constraints->max_uV;
1314
1315                 /* it's safe to autoconfigure fixed-voltage supplies
1316                  * and the constraints are used by list_voltage.
1317                  */
1318                 if (count == 1 && !cmin) {
1319                         cmin = 1;
1320                         cmax = INT_MAX;
1321                         constraints->min_uV = cmin;
1322                         constraints->max_uV = cmax;
1323                 }
1324
1325                 /* voltage constraints are optional */
1326                 if ((cmin == 0) && (cmax == 0))
1327                         return 0;
1328
1329                 /* else require explicit machine-level constraints */
1330                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
1331                         rdev_err(rdev, "invalid voltage constraints\n");
1332                         return -EINVAL;
1333                 }
1334
1335                 /* no need to loop voltages if range is continuous */
1336                 if (rdev->desc->continuous_voltage_range)
1337                         return 0;
1338
1339                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
1340                 for (i = 0; i < count; i++) {
1341                         int     value;
1342
1343                         value = ops->list_voltage(rdev, i);
1344                         if (value <= 0)
1345                                 continue;
1346
1347                         /* maybe adjust [min_uV..max_uV] */
1348                         if (value >= cmin && value < min_uV)
1349                                 min_uV = value;
1350                         if (value <= cmax && value > max_uV)
1351                                 max_uV = value;
1352                 }
1353
1354                 /* final: [min_uV..max_uV] valid iff constraints valid */
1355                 if (max_uV < min_uV) {
1356                         rdev_err(rdev,
1357                                  "unsupportable voltage constraints %u-%uuV\n",
1358                                  min_uV, max_uV);
1359                         return -EINVAL;
1360                 }
1361
1362                 /* use regulator's subset of machine constraints */
1363                 if (constraints->min_uV < min_uV) {
1364                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
1365                                  constraints->min_uV, min_uV);
1366                         constraints->min_uV = min_uV;
1367                 }
1368                 if (constraints->max_uV > max_uV) {
1369                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
1370                                  constraints->max_uV, max_uV);
1371                         constraints->max_uV = max_uV;
1372                 }
1373         }
1374
1375         return 0;
1376 }
1377
1378 static int machine_constraints_current(struct regulator_dev *rdev,
1379         struct regulation_constraints *constraints)
1380 {
1381         const struct regulator_ops *ops = rdev->desc->ops;
1382         int ret;
1383
1384         if (!constraints->min_uA && !constraints->max_uA)
1385                 return 0;
1386
1387         if (constraints->min_uA > constraints->max_uA) {
1388                 rdev_err(rdev, "Invalid current constraints\n");
1389                 return -EINVAL;
1390         }
1391
1392         if (!ops->set_current_limit || !ops->get_current_limit) {
1393                 rdev_warn(rdev, "Operation of current configuration missing\n");
1394                 return 0;
1395         }
1396
1397         /* Set regulator current in constraints range */
1398         ret = ops->set_current_limit(rdev, constraints->min_uA,
1399                         constraints->max_uA);
1400         if (ret < 0) {
1401                 rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
1402                 return ret;
1403         }
1404
1405         return 0;
1406 }
1407
1408 static int _regulator_do_enable(struct regulator_dev *rdev);
1409
1410 static int notif_set_limit(struct regulator_dev *rdev,
1411                            int (*set)(struct regulator_dev *, int, int, bool),
1412                            int limit, int severity)
1413 {
1414         bool enable;
1415
1416         if (limit == REGULATOR_NOTIF_LIMIT_DISABLE) {
1417                 enable = false;
1418                 limit = 0;
1419         } else {
1420                 enable = true;
1421         }
1422
1423         if (limit == REGULATOR_NOTIF_LIMIT_ENABLE)
1424                 limit = 0;
1425
1426         return set(rdev, limit, severity, enable);
1427 }
1428
1429 static int handle_notify_limits(struct regulator_dev *rdev,
1430                         int (*set)(struct regulator_dev *, int, int, bool),
1431                         struct notification_limit *limits)
1432 {
1433         int ret = 0;
1434
1435         if (!set)
1436                 return -EOPNOTSUPP;
1437
1438         if (limits->prot)
1439                 ret = notif_set_limit(rdev, set, limits->prot,
1440                                       REGULATOR_SEVERITY_PROT);
1441         if (ret)
1442                 return ret;
1443
1444         if (limits->err)
1445                 ret = notif_set_limit(rdev, set, limits->err,
1446                                       REGULATOR_SEVERITY_ERR);
1447         if (ret)
1448                 return ret;
1449
1450         if (limits->warn)
1451                 ret = notif_set_limit(rdev, set, limits->warn,
1452                                       REGULATOR_SEVERITY_WARN);
1453
1454         return ret;
1455 }
1456 /**
1457  * set_machine_constraints - sets regulator constraints
1458  * @rdev: regulator source
1459  *
1460  * Allows platform initialisation code to define and constrain
1461  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
1462  * Constraints *must* be set by platform code in order for some
1463  * regulator operations to proceed i.e. set_voltage, set_current_limit,
1464  * set_mode.
1465  */
1466 static int set_machine_constraints(struct regulator_dev *rdev)
1467 {
1468         int ret = 0;
1469         const struct regulator_ops *ops = rdev->desc->ops;
1470
1471         ret = machine_constraints_voltage(rdev, rdev->constraints);
1472         if (ret != 0)
1473                 return ret;
1474
1475         ret = machine_constraints_current(rdev, rdev->constraints);
1476         if (ret != 0)
1477                 return ret;
1478
1479         if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
1480                 ret = ops->set_input_current_limit(rdev,
1481                                                    rdev->constraints->ilim_uA);
1482                 if (ret < 0) {
1483                         rdev_err(rdev, "failed to set input limit: %pe\n", ERR_PTR(ret));
1484                         return ret;
1485                 }
1486         }
1487
1488         /* do we need to setup our suspend state */
1489         if (rdev->constraints->initial_state) {
1490                 ret = suspend_set_initial_state(rdev);
1491                 if (ret < 0) {
1492                         rdev_err(rdev, "failed to set suspend state: %pe\n", ERR_PTR(ret));
1493                         return ret;
1494                 }
1495         }
1496
1497         if (rdev->constraints->initial_mode) {
1498                 if (!ops->set_mode) {
1499                         rdev_err(rdev, "no set_mode operation\n");
1500                         return -EINVAL;
1501                 }
1502
1503                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1504                 if (ret < 0) {
1505                         rdev_err(rdev, "failed to set initial mode: %pe\n", ERR_PTR(ret));
1506                         return ret;
1507                 }
1508         } else if (rdev->constraints->system_load) {
1509                 /*
1510                  * We'll only apply the initial system load if an
1511                  * initial mode wasn't specified.
1512                  */
1513                 drms_uA_update(rdev);
1514         }
1515
1516         if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1517                 && ops->set_ramp_delay) {
1518                 ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1519                 if (ret < 0) {
1520                         rdev_err(rdev, "failed to set ramp_delay: %pe\n", ERR_PTR(ret));
1521                         return ret;
1522                 }
1523         }
1524
1525         if (rdev->constraints->pull_down && ops->set_pull_down) {
1526                 ret = ops->set_pull_down(rdev);
1527                 if (ret < 0) {
1528                         rdev_err(rdev, "failed to set pull down: %pe\n", ERR_PTR(ret));
1529                         return ret;
1530                 }
1531         }
1532
1533         if (rdev->constraints->soft_start && ops->set_soft_start) {
1534                 ret = ops->set_soft_start(rdev);
1535                 if (ret < 0) {
1536                         rdev_err(rdev, "failed to set soft start: %pe\n", ERR_PTR(ret));
1537                         return ret;
1538                 }
1539         }
1540
1541         /*
1542          * Existing logic does not warn if over_current_protection is given as
1543          * a constraint but driver does not support that. I think we should
1544          * warn about this type of issues as it is possible someone changes
1545          * PMIC on board to another type - and the another PMIC's driver does
1546          * not support setting protection. Board composer may happily believe
1547          * the DT limits are respected - especially if the new PMIC HW also
1548          * supports protection but the driver does not. I won't change the logic
1549          * without hearing more experienced opinion on this though.
1550          *
1551          * If warning is seen as a good idea then we can merge handling the
1552          * over-curret protection and detection and get rid of this special
1553          * handling.
1554          */
1555         if (rdev->constraints->over_current_protection
1556                 && ops->set_over_current_protection) {
1557                 int lim = rdev->constraints->over_curr_limits.prot;
1558
1559                 ret = ops->set_over_current_protection(rdev, lim,
1560                                                        REGULATOR_SEVERITY_PROT,
1561                                                        true);
1562                 if (ret < 0) {
1563                         rdev_err(rdev, "failed to set over current protection: %pe\n",
1564                                  ERR_PTR(ret));
1565                         return ret;
1566                 }
1567         }
1568
1569         if (rdev->constraints->over_current_detection)
1570                 ret = handle_notify_limits(rdev,
1571                                            ops->set_over_current_protection,
1572                                            &rdev->constraints->over_curr_limits);
1573         if (ret) {
1574                 if (ret != -EOPNOTSUPP) {
1575                         rdev_err(rdev, "failed to set over current limits: %pe\n",
1576                                  ERR_PTR(ret));
1577                         return ret;
1578                 }
1579                 rdev_warn(rdev,
1580                           "IC does not support requested over-current limits\n");
1581         }
1582
1583         if (rdev->constraints->over_voltage_detection)
1584                 ret = handle_notify_limits(rdev,
1585                                            ops->set_over_voltage_protection,
1586                                            &rdev->constraints->over_voltage_limits);
1587         if (ret) {
1588                 if (ret != -EOPNOTSUPP) {
1589                         rdev_err(rdev, "failed to set over voltage limits %pe\n",
1590                                  ERR_PTR(ret));
1591                         return ret;
1592                 }
1593                 rdev_warn(rdev,
1594                           "IC does not support requested over voltage limits\n");
1595         }
1596
1597         if (rdev->constraints->under_voltage_detection)
1598                 ret = handle_notify_limits(rdev,
1599                                            ops->set_under_voltage_protection,
1600                                            &rdev->constraints->under_voltage_limits);
1601         if (ret) {
1602                 if (ret != -EOPNOTSUPP) {
1603                         rdev_err(rdev, "failed to set under voltage limits %pe\n",
1604                                  ERR_PTR(ret));
1605                         return ret;
1606                 }
1607                 rdev_warn(rdev,
1608                           "IC does not support requested under voltage limits\n");
1609         }
1610
1611         if (rdev->constraints->over_temp_detection)
1612                 ret = handle_notify_limits(rdev,
1613                                            ops->set_thermal_protection,
1614                                            &rdev->constraints->temp_limits);
1615         if (ret) {
1616                 if (ret != -EOPNOTSUPP) {
1617                         rdev_err(rdev, "failed to set temperature limits %pe\n",
1618                                  ERR_PTR(ret));
1619                         return ret;
1620                 }
1621                 rdev_warn(rdev,
1622                           "IC does not support requested temperature limits\n");
1623         }
1624
1625         if (rdev->constraints->active_discharge && ops->set_active_discharge) {
1626                 bool ad_state = (rdev->constraints->active_discharge ==
1627                               REGULATOR_ACTIVE_DISCHARGE_ENABLE) ? true : false;
1628
1629                 ret = ops->set_active_discharge(rdev, ad_state);
1630                 if (ret < 0) {
1631                         rdev_err(rdev, "failed to set active discharge: %pe\n", ERR_PTR(ret));
1632                         return ret;
1633                 }
1634         }
1635
1636         /*
1637          * If there is no mechanism for controlling the regulator then
1638          * flag it as always_on so we don't end up duplicating checks
1639          * for this so much.  Note that we could control the state of
1640          * a supply to control the output on a regulator that has no
1641          * direct control.
1642          */
1643         if (!rdev->ena_pin && !ops->enable) {
1644                 if (rdev->supply_name && !rdev->supply)
1645                         return -EPROBE_DEFER;
1646
1647                 if (rdev->supply)
1648                         rdev->constraints->always_on =
1649                                 rdev->supply->rdev->constraints->always_on;
1650                 else
1651                         rdev->constraints->always_on = true;
1652         }
1653
1654         /* If the constraints say the regulator should be on at this point
1655          * and we have control then make sure it is enabled.
1656          */
1657         if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1658                 /* If we want to enable this regulator, make sure that we know
1659                  * the supplying regulator.
1660                  */
1661                 if (rdev->supply_name && !rdev->supply)
1662                         return -EPROBE_DEFER;
1663
1664                 /* If supplying regulator has already been enabled,
1665                  * it's not intended to have use_count increment
1666                  * when rdev is only boot-on.
1667                  */
1668                 if (rdev->supply &&
1669                     (rdev->constraints->always_on ||
1670                      !regulator_is_enabled(rdev->supply))) {
1671                         ret = regulator_enable(rdev->supply);
1672                         if (ret < 0) {
1673                                 _regulator_put(rdev->supply);
1674                                 rdev->supply = NULL;
1675                                 return ret;
1676                         }
1677                 }
1678
1679                 ret = _regulator_do_enable(rdev);
1680                 if (ret < 0 && ret != -EINVAL) {
1681                         rdev_err(rdev, "failed to enable: %pe\n", ERR_PTR(ret));
1682                         return ret;
1683                 }
1684
1685                 if (rdev->constraints->always_on)
1686                         rdev->use_count++;
1687         } else if (rdev->desc->off_on_delay) {
1688                 rdev->last_off = ktime_get();
1689         }
1690
1691         print_constraints(rdev);
1692         return 0;
1693 }
1694
1695 /**
1696  * set_supply - set regulator supply regulator
1697  * @rdev: regulator (locked)
1698  * @supply_rdev: supply regulator (locked))
1699  *
1700  * Called by platform initialisation code to set the supply regulator for this
1701  * regulator. This ensures that a regulators supply will also be enabled by the
1702  * core if it's child is enabled.
1703  */
1704 static int set_supply(struct regulator_dev *rdev,
1705                       struct regulator_dev *supply_rdev)
1706 {
1707         int err;
1708
1709         rdev_dbg(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1710
1711         if (!try_module_get(supply_rdev->owner))
1712                 return -ENODEV;
1713
1714         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1715         if (rdev->supply == NULL) {
1716                 module_put(supply_rdev->owner);
1717                 err = -ENOMEM;
1718                 return err;
1719         }
1720         supply_rdev->open_count++;
1721
1722         return 0;
1723 }
1724
1725 /**
1726  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1727  * @rdev:         regulator source
1728  * @consumer_dev_name: dev_name() string for device supply applies to
1729  * @supply:       symbolic name for supply
1730  *
1731  * Allows platform initialisation code to map physical regulator
1732  * sources to symbolic names for supplies for use by devices.  Devices
1733  * should use these symbolic names to request regulators, avoiding the
1734  * need to provide board-specific regulator names as platform data.
1735  */
1736 static int set_consumer_device_supply(struct regulator_dev *rdev,
1737                                       const char *consumer_dev_name,
1738                                       const char *supply)
1739 {
1740         struct regulator_map *node, *new_node;
1741         int has_dev;
1742
1743         if (supply == NULL)
1744                 return -EINVAL;
1745
1746         if (consumer_dev_name != NULL)
1747                 has_dev = 1;
1748         else
1749                 has_dev = 0;
1750
1751         new_node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1752         if (new_node == NULL)
1753                 return -ENOMEM;
1754
1755         new_node->regulator = rdev;
1756         new_node->supply = supply;
1757
1758         if (has_dev) {
1759                 new_node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1760                 if (new_node->dev_name == NULL) {
1761                         kfree(new_node);
1762                         return -ENOMEM;
1763                 }
1764         }
1765
1766         mutex_lock(&regulator_list_mutex);
1767         list_for_each_entry(node, &regulator_map_list, list) {
1768                 if (node->dev_name && consumer_dev_name) {
1769                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1770                                 continue;
1771                 } else if (node->dev_name || consumer_dev_name) {
1772                         continue;
1773                 }
1774
1775                 if (strcmp(node->supply, supply) != 0)
1776                         continue;
1777
1778                 pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1779                          consumer_dev_name,
1780                          dev_name(&node->regulator->dev),
1781                          node->regulator->desc->name,
1782                          supply,
1783                          dev_name(&rdev->dev), rdev_get_name(rdev));
1784                 goto fail;
1785         }
1786
1787         list_add(&new_node->list, &regulator_map_list);
1788         mutex_unlock(&regulator_list_mutex);
1789
1790         return 0;
1791
1792 fail:
1793         mutex_unlock(&regulator_list_mutex);
1794         kfree(new_node->dev_name);
1795         kfree(new_node);
1796         return -EBUSY;
1797 }
1798
1799 static void unset_regulator_supplies(struct regulator_dev *rdev)
1800 {
1801         struct regulator_map *node, *n;
1802
1803         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1804                 if (rdev == node->regulator) {
1805                         list_del(&node->list);
1806                         kfree(node->dev_name);
1807                         kfree(node);
1808                 }
1809         }
1810 }
1811
1812 #ifdef CONFIG_DEBUG_FS
1813 static ssize_t constraint_flags_read_file(struct file *file,
1814                                           char __user *user_buf,
1815                                           size_t count, loff_t *ppos)
1816 {
1817         const struct regulator *regulator = file->private_data;
1818         const struct regulation_constraints *c = regulator->rdev->constraints;
1819         char *buf;
1820         ssize_t ret;
1821
1822         if (!c)
1823                 return 0;
1824
1825         buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1826         if (!buf)
1827                 return -ENOMEM;
1828
1829         ret = snprintf(buf, PAGE_SIZE,
1830                         "always_on: %u\n"
1831                         "boot_on: %u\n"
1832                         "apply_uV: %u\n"
1833                         "ramp_disable: %u\n"
1834                         "soft_start: %u\n"
1835                         "pull_down: %u\n"
1836                         "over_current_protection: %u\n",
1837                         c->always_on,
1838                         c->boot_on,
1839                         c->apply_uV,
1840                         c->ramp_disable,
1841                         c->soft_start,
1842                         c->pull_down,
1843                         c->over_current_protection);
1844
1845         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
1846         kfree(buf);
1847
1848         return ret;
1849 }
1850
1851 #endif
1852
1853 static const struct file_operations constraint_flags_fops = {
1854 #ifdef CONFIG_DEBUG_FS
1855         .open = simple_open,
1856         .read = constraint_flags_read_file,
1857         .llseek = default_llseek,
1858 #endif
1859 };
1860
1861 #define REG_STR_SIZE    64
1862
1863 static struct regulator *create_regulator(struct regulator_dev *rdev,
1864                                           struct device *dev,
1865                                           const char *supply_name)
1866 {
1867         struct regulator *regulator;
1868         int err = 0;
1869
1870         lockdep_assert_held_once(&rdev->mutex.base);
1871
1872         if (dev) {
1873                 char buf[REG_STR_SIZE];
1874                 int size;
1875
1876                 size = snprintf(buf, REG_STR_SIZE, "%s-%s",
1877                                 dev->kobj.name, supply_name);
1878                 if (size >= REG_STR_SIZE)
1879                         return NULL;
1880
1881                 supply_name = kstrdup(buf, GFP_KERNEL);
1882                 if (supply_name == NULL)
1883                         return NULL;
1884         } else {
1885                 supply_name = kstrdup_const(supply_name, GFP_KERNEL);
1886                 if (supply_name == NULL)
1887                         return NULL;
1888         }
1889
1890         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1891         if (regulator == NULL) {
1892                 kfree_const(supply_name);
1893                 return NULL;
1894         }
1895
1896         regulator->rdev = rdev;
1897         regulator->supply_name = supply_name;
1898
1899         list_add(&regulator->list, &rdev->consumer_list);
1900
1901         if (dev) {
1902                 regulator->dev = dev;
1903
1904                 /* Add a link to the device sysfs entry */
1905                 err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
1906                                                supply_name);
1907                 if (err) {
1908                         rdev_dbg(rdev, "could not add device link %s: %pe\n",
1909                                   dev->kobj.name, ERR_PTR(err));
1910                         /* non-fatal */
1911                 }
1912         }
1913
1914         if (err != -EEXIST) {
1915                 regulator->debugfs = debugfs_create_dir(supply_name, rdev->debugfs);
1916                 if (IS_ERR(regulator->debugfs)) {
1917                         rdev_dbg(rdev, "Failed to create debugfs directory\n");
1918                         regulator->debugfs = NULL;
1919                 }
1920         }
1921
1922         if (regulator->debugfs) {
1923                 debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1924                                    &regulator->uA_load);
1925                 debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1926                                    &regulator->voltage[PM_SUSPEND_ON].min_uV);
1927                 debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1928                                    &regulator->voltage[PM_SUSPEND_ON].max_uV);
1929                 debugfs_create_file("constraint_flags", 0444, regulator->debugfs,
1930                                     regulator, &constraint_flags_fops);
1931         }
1932
1933         /*
1934          * Check now if the regulator is an always on regulator - if
1935          * it is then we don't need to do nearly so much work for
1936          * enable/disable calls.
1937          */
1938         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS) &&
1939             _regulator_is_enabled(rdev))
1940                 regulator->always_on = true;
1941
1942         return regulator;
1943 }
1944
1945 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1946 {
1947         if (rdev->constraints && rdev->constraints->enable_time)
1948                 return rdev->constraints->enable_time;
1949         if (rdev->desc->ops->enable_time)
1950                 return rdev->desc->ops->enable_time(rdev);
1951         return rdev->desc->enable_time;
1952 }
1953
1954 static struct regulator_supply_alias *regulator_find_supply_alias(
1955                 struct device *dev, const char *supply)
1956 {
1957         struct regulator_supply_alias *map;
1958
1959         list_for_each_entry(map, &regulator_supply_alias_list, list)
1960                 if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1961                         return map;
1962
1963         return NULL;
1964 }
1965
1966 static void regulator_supply_alias(struct device **dev, const char **supply)
1967 {
1968         struct regulator_supply_alias *map;
1969
1970         map = regulator_find_supply_alias(*dev, *supply);
1971         if (map) {
1972                 dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1973                                 *supply, map->alias_supply,
1974                                 dev_name(map->alias_dev));
1975                 *dev = map->alias_dev;
1976                 *supply = map->alias_supply;
1977         }
1978 }
1979
1980 static int regulator_match(struct device *dev, const void *data)
1981 {
1982         struct regulator_dev *r = dev_to_rdev(dev);
1983
1984         return strcmp(rdev_get_name(r), data) == 0;
1985 }
1986
1987 static struct regulator_dev *regulator_lookup_by_name(const char *name)
1988 {
1989         struct device *dev;
1990
1991         dev = class_find_device(&regulator_class, NULL, name, regulator_match);
1992
1993         return dev ? dev_to_rdev(dev) : NULL;
1994 }
1995
1996 /**
1997  * regulator_dev_lookup - lookup a regulator device.
1998  * @dev: device for regulator "consumer".
1999  * @supply: Supply name or regulator ID.
2000  *
2001  * If successful, returns a struct regulator_dev that corresponds to the name
2002  * @supply and with the embedded struct device refcount incremented by one.
2003  * The refcount must be dropped by calling put_device().
2004  * On failure one of the following ERR-PTR-encoded values is returned:
2005  * -ENODEV if lookup fails permanently, -EPROBE_DEFER if lookup could succeed
2006  * in the future.
2007  */
2008 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
2009                                                   const char *supply)
2010 {
2011         struct regulator_dev *r = NULL;
2012         struct device_node *node;
2013         struct regulator_map *map;
2014         const char *devname = NULL;
2015
2016         regulator_supply_alias(&dev, &supply);
2017
2018         /* first do a dt based lookup */
2019         if (dev && dev->of_node) {
2020                 node = of_get_regulator(dev, supply);
2021                 if (node) {
2022                         r = of_find_regulator_by_node(node);
2023                         of_node_put(node);
2024                         if (r)
2025                                 return r;
2026
2027                         /*
2028                          * We have a node, but there is no device.
2029                          * assume it has not registered yet.
2030                          */
2031                         return ERR_PTR(-EPROBE_DEFER);
2032                 }
2033         }
2034
2035         /* if not found, try doing it non-dt way */
2036         if (dev)
2037                 devname = dev_name(dev);
2038
2039         mutex_lock(&regulator_list_mutex);
2040         list_for_each_entry(map, &regulator_map_list, list) {
2041                 /* If the mapping has a device set up it must match */
2042                 if (map->dev_name &&
2043                     (!devname || strcmp(map->dev_name, devname)))
2044                         continue;
2045
2046                 if (strcmp(map->supply, supply) == 0 &&
2047                     get_device(&map->regulator->dev)) {
2048                         r = map->regulator;
2049                         break;
2050                 }
2051         }
2052         mutex_unlock(&regulator_list_mutex);
2053
2054         if (r)
2055                 return r;
2056
2057         r = regulator_lookup_by_name(supply);
2058         if (r)
2059                 return r;
2060
2061         return ERR_PTR(-ENODEV);
2062 }
2063
2064 static int regulator_resolve_supply(struct regulator_dev *rdev)
2065 {
2066         struct regulator_dev *r;
2067         struct device *dev = rdev->dev.parent;
2068         struct ww_acquire_ctx ww_ctx;
2069         int ret = 0;
2070
2071         /* No supply to resolve? */
2072         if (!rdev->supply_name)
2073                 return 0;
2074
2075         /* Supply already resolved? (fast-path without locking contention) */
2076         if (rdev->supply)
2077                 return 0;
2078
2079         r = regulator_dev_lookup(dev, rdev->supply_name);
2080         if (IS_ERR(r)) {
2081                 ret = PTR_ERR(r);
2082
2083                 /* Did the lookup explicitly defer for us? */
2084                 if (ret == -EPROBE_DEFER)
2085                         goto out;
2086
2087                 if (have_full_constraints()) {
2088                         r = dummy_regulator_rdev;
2089                         get_device(&r->dev);
2090                 } else {
2091                         dev_err(dev, "Failed to resolve %s-supply for %s\n",
2092                                 rdev->supply_name, rdev->desc->name);
2093                         ret = -EPROBE_DEFER;
2094                         goto out;
2095                 }
2096         }
2097
2098         if (r == rdev) {
2099                 dev_err(dev, "Supply for %s (%s) resolved to itself\n",
2100                         rdev->desc->name, rdev->supply_name);
2101                 if (!have_full_constraints()) {
2102                         ret = -EINVAL;
2103                         goto out;
2104                 }
2105                 r = dummy_regulator_rdev;
2106                 get_device(&r->dev);
2107         }
2108
2109         /*
2110          * If the supply's parent device is not the same as the
2111          * regulator's parent device, then ensure the parent device
2112          * is bound before we resolve the supply, in case the parent
2113          * device get probe deferred and unregisters the supply.
2114          */
2115         if (r->dev.parent && r->dev.parent != rdev->dev.parent) {
2116                 if (!device_is_bound(r->dev.parent)) {
2117                         put_device(&r->dev);
2118                         ret = -EPROBE_DEFER;
2119                         goto out;
2120                 }
2121         }
2122
2123         /* Recursively resolve the supply of the supply */
2124         ret = regulator_resolve_supply(r);
2125         if (ret < 0) {
2126                 put_device(&r->dev);
2127                 goto out;
2128         }
2129
2130         /*
2131          * Recheck rdev->supply with rdev->mutex lock held to avoid a race
2132          * between rdev->supply null check and setting rdev->supply in
2133          * set_supply() from concurrent tasks.
2134          */
2135         regulator_lock_two(rdev, r, &ww_ctx);
2136
2137         /* Supply just resolved by a concurrent task? */
2138         if (rdev->supply) {
2139                 regulator_unlock_two(rdev, r, &ww_ctx);
2140                 put_device(&r->dev);
2141                 goto out;
2142         }
2143
2144         ret = set_supply(rdev, r);
2145         if (ret < 0) {
2146                 regulator_unlock_two(rdev, r, &ww_ctx);
2147                 put_device(&r->dev);
2148                 goto out;
2149         }
2150
2151         regulator_unlock_two(rdev, r, &ww_ctx);
2152
2153         /*
2154          * In set_machine_constraints() we may have turned this regulator on
2155          * but we couldn't propagate to the supply if it hadn't been resolved
2156          * yet.  Do it now.
2157          */
2158         if (rdev->use_count) {
2159                 ret = regulator_enable(rdev->supply);
2160                 if (ret < 0) {
2161                         _regulator_put(rdev->supply);
2162                         rdev->supply = NULL;
2163                         goto out;
2164                 }
2165         }
2166
2167 out:
2168         return ret;
2169 }
2170
2171 /* Internal regulator request function */
2172 struct regulator *_regulator_get(struct device *dev, const char *id,
2173                                  enum regulator_get_type get_type)
2174 {
2175         struct regulator_dev *rdev;
2176         struct regulator *regulator;
2177         struct device_link *link;
2178         int ret;
2179
2180         if (get_type >= MAX_GET_TYPE) {
2181                 dev_err(dev, "invalid type %d in %s\n", get_type, __func__);
2182                 return ERR_PTR(-EINVAL);
2183         }
2184
2185         if (id == NULL) {
2186                 pr_err("get() with no identifier\n");
2187                 return ERR_PTR(-EINVAL);
2188         }
2189
2190         rdev = regulator_dev_lookup(dev, id);
2191         if (IS_ERR(rdev)) {
2192                 ret = PTR_ERR(rdev);
2193
2194                 /*
2195                  * If regulator_dev_lookup() fails with error other
2196                  * than -ENODEV our job here is done, we simply return it.
2197                  */
2198                 if (ret != -ENODEV)
2199                         return ERR_PTR(ret);
2200
2201                 if (!have_full_constraints()) {
2202                         dev_warn(dev,
2203                                  "incomplete constraints, dummy supplies not allowed\n");
2204                         return ERR_PTR(-ENODEV);
2205                 }
2206
2207                 switch (get_type) {
2208                 case NORMAL_GET:
2209                         /*
2210                          * Assume that a regulator is physically present and
2211                          * enabled, even if it isn't hooked up, and just
2212                          * provide a dummy.
2213                          */
2214                         dev_warn(dev, "supply %s not found, using dummy regulator\n", id);
2215                         rdev = dummy_regulator_rdev;
2216                         get_device(&rdev->dev);
2217                         break;
2218
2219                 case EXCLUSIVE_GET:
2220                         dev_warn(dev,
2221                                  "dummy supplies not allowed for exclusive requests\n");
2222                         fallthrough;
2223
2224                 default:
2225                         return ERR_PTR(-ENODEV);
2226                 }
2227         }
2228
2229         if (rdev->exclusive) {
2230                 regulator = ERR_PTR(-EPERM);
2231                 put_device(&rdev->dev);
2232                 return regulator;
2233         }
2234
2235         if (get_type == EXCLUSIVE_GET && rdev->open_count) {
2236                 regulator = ERR_PTR(-EBUSY);
2237                 put_device(&rdev->dev);
2238                 return regulator;
2239         }
2240
2241         mutex_lock(&regulator_list_mutex);
2242         ret = (rdev->coupling_desc.n_resolved != rdev->coupling_desc.n_coupled);
2243         mutex_unlock(&regulator_list_mutex);
2244
2245         if (ret != 0) {
2246                 regulator = ERR_PTR(-EPROBE_DEFER);
2247                 put_device(&rdev->dev);
2248                 return regulator;
2249         }
2250
2251         ret = regulator_resolve_supply(rdev);
2252         if (ret < 0) {
2253                 regulator = ERR_PTR(ret);
2254                 put_device(&rdev->dev);
2255                 return regulator;
2256         }
2257
2258         if (!try_module_get(rdev->owner)) {
2259                 regulator = ERR_PTR(-EPROBE_DEFER);
2260                 put_device(&rdev->dev);
2261                 return regulator;
2262         }
2263
2264         regulator_lock(rdev);
2265         regulator = create_regulator(rdev, dev, id);
2266         regulator_unlock(rdev);
2267         if (regulator == NULL) {
2268                 regulator = ERR_PTR(-ENOMEM);
2269                 module_put(rdev->owner);
2270                 put_device(&rdev->dev);
2271                 return regulator;
2272         }
2273
2274         rdev->open_count++;
2275         if (get_type == EXCLUSIVE_GET) {
2276                 rdev->exclusive = 1;
2277
2278                 ret = _regulator_is_enabled(rdev);
2279                 if (ret > 0) {
2280                         rdev->use_count = 1;
2281                         regulator->enable_count = 1;
2282
2283                         /* Propagate the regulator state to its supply */
2284                         if (rdev->supply) {
2285                                 ret = regulator_enable(rdev->supply);
2286                                 if (ret < 0) {
2287                                         destroy_regulator(regulator);
2288                                         module_put(rdev->owner);
2289                                         put_device(&rdev->dev);
2290                                         return ERR_PTR(ret);
2291                                 }
2292                         }
2293                 } else {
2294                         rdev->use_count = 0;
2295                         regulator->enable_count = 0;
2296                 }
2297         }
2298
2299         link = device_link_add(dev, &rdev->dev, DL_FLAG_STATELESS);
2300         if (!IS_ERR_OR_NULL(link))
2301                 regulator->device_link = true;
2302
2303         return regulator;
2304 }
2305
2306 /**
2307  * regulator_get - lookup and obtain a reference to a regulator.
2308  * @dev: device for regulator "consumer"
2309  * @id: Supply name or regulator ID.
2310  *
2311  * Returns a struct regulator corresponding to the regulator producer,
2312  * or IS_ERR() condition containing errno.
2313  *
2314  * Use of supply names configured via set_consumer_device_supply() is
2315  * strongly encouraged.  It is recommended that the supply name used
2316  * should match the name used for the supply and/or the relevant
2317  * device pins in the datasheet.
2318  */
2319 struct regulator *regulator_get(struct device *dev, const char *id)
2320 {
2321         return _regulator_get(dev, id, NORMAL_GET);
2322 }
2323 EXPORT_SYMBOL_GPL(regulator_get);
2324
2325 /**
2326  * regulator_get_exclusive - obtain exclusive access to a regulator.
2327  * @dev: device for regulator "consumer"
2328  * @id: Supply name or regulator ID.
2329  *
2330  * Returns a struct regulator corresponding to the regulator producer,
2331  * or IS_ERR() condition containing errno.  Other consumers will be
2332  * unable to obtain this regulator while this reference is held and the
2333  * use count for the regulator will be initialised to reflect the current
2334  * state of the regulator.
2335  *
2336  * This is intended for use by consumers which cannot tolerate shared
2337  * use of the regulator such as those which need to force the
2338  * regulator off for correct operation of the hardware they are
2339  * controlling.
2340  *
2341  * Use of supply names configured via set_consumer_device_supply() is
2342  * strongly encouraged.  It is recommended that the supply name used
2343  * should match the name used for the supply and/or the relevant
2344  * device pins in the datasheet.
2345  */
2346 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
2347 {
2348         return _regulator_get(dev, id, EXCLUSIVE_GET);
2349 }
2350 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
2351
2352 /**
2353  * regulator_get_optional - obtain optional access to a regulator.
2354  * @dev: device for regulator "consumer"
2355  * @id: Supply name or regulator ID.
2356  *
2357  * Returns a struct regulator corresponding to the regulator producer,
2358  * or IS_ERR() condition containing errno.
2359  *
2360  * This is intended for use by consumers for devices which can have
2361  * some supplies unconnected in normal use, such as some MMC devices.
2362  * It can allow the regulator core to provide stub supplies for other
2363  * supplies requested using normal regulator_get() calls without
2364  * disrupting the operation of drivers that can handle absent
2365  * supplies.
2366  *
2367  * Use of supply names configured via set_consumer_device_supply() is
2368  * strongly encouraged.  It is recommended that the supply name used
2369  * should match the name used for the supply and/or the relevant
2370  * device pins in the datasheet.
2371  */
2372 struct regulator *regulator_get_optional(struct device *dev, const char *id)
2373 {
2374         return _regulator_get(dev, id, OPTIONAL_GET);
2375 }
2376 EXPORT_SYMBOL_GPL(regulator_get_optional);
2377
2378 static void destroy_regulator(struct regulator *regulator)
2379 {
2380         struct regulator_dev *rdev = regulator->rdev;
2381
2382         debugfs_remove_recursive(regulator->debugfs);
2383
2384         if (regulator->dev) {
2385                 if (regulator->device_link)
2386                         device_link_remove(regulator->dev, &rdev->dev);
2387
2388                 /* remove any sysfs entries */
2389                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
2390         }
2391
2392         regulator_lock(rdev);
2393         list_del(&regulator->list);
2394
2395         rdev->open_count--;
2396         rdev->exclusive = 0;
2397         regulator_unlock(rdev);
2398
2399         kfree_const(regulator->supply_name);
2400         kfree(regulator);
2401 }
2402
2403 /* regulator_list_mutex lock held by regulator_put() */
2404 static void _regulator_put(struct regulator *regulator)
2405 {
2406         struct regulator_dev *rdev;
2407
2408         if (IS_ERR_OR_NULL(regulator))
2409                 return;
2410
2411         lockdep_assert_held_once(&regulator_list_mutex);
2412
2413         /* Docs say you must disable before calling regulator_put() */
2414         WARN_ON(regulator->enable_count);
2415
2416         rdev = regulator->rdev;
2417
2418         destroy_regulator(regulator);
2419
2420         module_put(rdev->owner);
2421         put_device(&rdev->dev);
2422 }
2423
2424 /**
2425  * regulator_put - "free" the regulator source
2426  * @regulator: regulator source
2427  *
2428  * Note: drivers must ensure that all regulator_enable calls made on this
2429  * regulator source are balanced by regulator_disable calls prior to calling
2430  * this function.
2431  */
2432 void regulator_put(struct regulator *regulator)
2433 {
2434         mutex_lock(&regulator_list_mutex);
2435         _regulator_put(regulator);
2436         mutex_unlock(&regulator_list_mutex);
2437 }
2438 EXPORT_SYMBOL_GPL(regulator_put);
2439
2440 /**
2441  * regulator_register_supply_alias - Provide device alias for supply lookup
2442  *
2443  * @dev: device that will be given as the regulator "consumer"
2444  * @id: Supply name or regulator ID
2445  * @alias_dev: device that should be used to lookup the supply
2446  * @alias_id: Supply name or regulator ID that should be used to lookup the
2447  * supply
2448  *
2449  * All lookups for id on dev will instead be conducted for alias_id on
2450  * alias_dev.
2451  */
2452 int regulator_register_supply_alias(struct device *dev, const char *id,
2453                                     struct device *alias_dev,
2454                                     const char *alias_id)
2455 {
2456         struct regulator_supply_alias *map;
2457
2458         map = regulator_find_supply_alias(dev, id);
2459         if (map)
2460                 return -EEXIST;
2461
2462         map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
2463         if (!map)
2464                 return -ENOMEM;
2465
2466         map->src_dev = dev;
2467         map->src_supply = id;
2468         map->alias_dev = alias_dev;
2469         map->alias_supply = alias_id;
2470
2471         list_add(&map->list, &regulator_supply_alias_list);
2472
2473         pr_info("Adding alias for supply %s,%s -> %s,%s\n",
2474                 id, dev_name(dev), alias_id, dev_name(alias_dev));
2475
2476         return 0;
2477 }
2478 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
2479
2480 /**
2481  * regulator_unregister_supply_alias - Remove device alias
2482  *
2483  * @dev: device that will be given as the regulator "consumer"
2484  * @id: Supply name or regulator ID
2485  *
2486  * Remove a lookup alias if one exists for id on dev.
2487  */
2488 void regulator_unregister_supply_alias(struct device *dev, const char *id)
2489 {
2490         struct regulator_supply_alias *map;
2491
2492         map = regulator_find_supply_alias(dev, id);
2493         if (map) {
2494                 list_del(&map->list);
2495                 kfree(map);
2496         }
2497 }
2498 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
2499
2500 /**
2501  * regulator_bulk_register_supply_alias - register multiple aliases
2502  *
2503  * @dev: device that will be given as the regulator "consumer"
2504  * @id: List of supply names or regulator IDs
2505  * @alias_dev: device that should be used to lookup the supply
2506  * @alias_id: List of supply names or regulator IDs that should be used to
2507  * lookup the supply
2508  * @num_id: Number of aliases to register
2509  *
2510  * @return 0 on success, an errno on failure.
2511  *
2512  * This helper function allows drivers to register several supply
2513  * aliases in one operation.  If any of the aliases cannot be
2514  * registered any aliases that were registered will be removed
2515  * before returning to the caller.
2516  */
2517 int regulator_bulk_register_supply_alias(struct device *dev,
2518                                          const char *const *id,
2519                                          struct device *alias_dev,
2520                                          const char *const *alias_id,
2521                                          int num_id)
2522 {
2523         int i;
2524         int ret;
2525
2526         for (i = 0; i < num_id; ++i) {
2527                 ret = regulator_register_supply_alias(dev, id[i], alias_dev,
2528                                                       alias_id[i]);
2529                 if (ret < 0)
2530                         goto err;
2531         }
2532
2533         return 0;
2534
2535 err:
2536         dev_err(dev,
2537                 "Failed to create supply alias %s,%s -> %s,%s\n",
2538                 id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
2539
2540         while (--i >= 0)
2541                 regulator_unregister_supply_alias(dev, id[i]);
2542
2543         return ret;
2544 }
2545 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
2546
2547 /**
2548  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
2549  *
2550  * @dev: device that will be given as the regulator "consumer"
2551  * @id: List of supply names or regulator IDs
2552  * @num_id: Number of aliases to unregister
2553  *
2554  * This helper function allows drivers to unregister several supply
2555  * aliases in one operation.
2556  */
2557 void regulator_bulk_unregister_supply_alias(struct device *dev,
2558                                             const char *const *id,
2559                                             int num_id)
2560 {
2561         int i;
2562
2563         for (i = 0; i < num_id; ++i)
2564                 regulator_unregister_supply_alias(dev, id[i]);
2565 }
2566 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
2567
2568
2569 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
2570 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
2571                                 const struct regulator_config *config)
2572 {
2573         struct regulator_enable_gpio *pin, *new_pin;
2574         struct gpio_desc *gpiod;
2575
2576         gpiod = config->ena_gpiod;
2577         new_pin = kzalloc(sizeof(*new_pin), GFP_KERNEL);
2578
2579         mutex_lock(&regulator_list_mutex);
2580
2581         list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
2582                 if (pin->gpiod == gpiod) {
2583                         rdev_dbg(rdev, "GPIO is already used\n");
2584                         goto update_ena_gpio_to_rdev;
2585                 }
2586         }
2587
2588         if (new_pin == NULL) {
2589                 mutex_unlock(&regulator_list_mutex);
2590                 return -ENOMEM;
2591         }
2592
2593         pin = new_pin;
2594         new_pin = NULL;
2595
2596         pin->gpiod = gpiod;
2597         list_add(&pin->list, &regulator_ena_gpio_list);
2598
2599 update_ena_gpio_to_rdev:
2600         pin->request_count++;
2601         rdev->ena_pin = pin;
2602
2603         mutex_unlock(&regulator_list_mutex);
2604         kfree(new_pin);
2605
2606         return 0;
2607 }
2608
2609 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
2610 {
2611         struct regulator_enable_gpio *pin, *n;
2612
2613         if (!rdev->ena_pin)
2614                 return;
2615
2616         /* Free the GPIO only in case of no use */
2617         list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
2618                 if (pin != rdev->ena_pin)
2619                         continue;
2620
2621                 if (--pin->request_count)
2622                         break;
2623
2624                 gpiod_put(pin->gpiod);
2625                 list_del(&pin->list);
2626                 kfree(pin);
2627                 break;
2628         }
2629
2630         rdev->ena_pin = NULL;
2631 }
2632
2633 /**
2634  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
2635  * @rdev: regulator_dev structure
2636  * @enable: enable GPIO at initial use?
2637  *
2638  * GPIO is enabled in case of initial use. (enable_count is 0)
2639  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
2640  */
2641 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
2642 {
2643         struct regulator_enable_gpio *pin = rdev->ena_pin;
2644
2645         if (!pin)
2646                 return -EINVAL;
2647
2648         if (enable) {
2649                 /* Enable GPIO at initial use */
2650                 if (pin->enable_count == 0)
2651                         gpiod_set_value_cansleep(pin->gpiod, 1);
2652
2653                 pin->enable_count++;
2654         } else {
2655                 if (pin->enable_count > 1) {
2656                         pin->enable_count--;
2657                         return 0;
2658                 }
2659
2660                 /* Disable GPIO if not used */
2661                 if (pin->enable_count <= 1) {
2662                         gpiod_set_value_cansleep(pin->gpiod, 0);
2663                         pin->enable_count = 0;
2664                 }
2665         }
2666
2667         return 0;
2668 }
2669
2670 /**
2671  * _regulator_delay_helper - a delay helper function
2672  * @delay: time to delay in microseconds
2673  *
2674  * Delay for the requested amount of time as per the guidelines in:
2675  *
2676  *     Documentation/timers/timers-howto.rst
2677  *
2678  * The assumption here is that these regulator operations will never used in
2679  * atomic context and therefore sleeping functions can be used.
2680  */
2681 static void _regulator_delay_helper(unsigned int delay)
2682 {
2683         unsigned int ms = delay / 1000;
2684         unsigned int us = delay % 1000;
2685
2686         if (ms > 0) {
2687                 /*
2688                  * For small enough values, handle super-millisecond
2689                  * delays in the usleep_range() call below.
2690                  */
2691                 if (ms < 20)
2692                         us += ms * 1000;
2693                 else
2694                         msleep(ms);
2695         }
2696
2697         /*
2698          * Give the scheduler some room to coalesce with any other
2699          * wakeup sources. For delays shorter than 10 us, don't even
2700          * bother setting up high-resolution timers and just busy-
2701          * loop.
2702          */
2703         if (us >= 10)
2704                 usleep_range(us, us + 100);
2705         else
2706                 udelay(us);
2707 }
2708
2709 /**
2710  * _regulator_check_status_enabled
2711  *
2712  * A helper function to check if the regulator status can be interpreted
2713  * as 'regulator is enabled'.
2714  * @rdev: the regulator device to check
2715  *
2716  * Return:
2717  * * 1                  - if status shows regulator is in enabled state
2718  * * 0                  - if not enabled state
2719  * * Error Value        - as received from ops->get_status()
2720  */
2721 static inline int _regulator_check_status_enabled(struct regulator_dev *rdev)
2722 {
2723         int ret = rdev->desc->ops->get_status(rdev);
2724
2725         if (ret < 0) {
2726                 rdev_info(rdev, "get_status returned error: %d\n", ret);
2727                 return ret;
2728         }
2729
2730         switch (ret) {
2731         case REGULATOR_STATUS_OFF:
2732         case REGULATOR_STATUS_ERROR:
2733         case REGULATOR_STATUS_UNDEFINED:
2734                 return 0;
2735         default:
2736                 return 1;
2737         }
2738 }
2739
2740 static int _regulator_do_enable(struct regulator_dev *rdev)
2741 {
2742         int ret, delay;
2743
2744         /* Query before enabling in case configuration dependent.  */
2745         ret = _regulator_get_enable_time(rdev);
2746         if (ret >= 0) {
2747                 delay = ret;
2748         } else {
2749                 rdev_warn(rdev, "enable_time() failed: %pe\n", ERR_PTR(ret));
2750                 delay = 0;
2751         }
2752
2753         trace_regulator_enable(rdev_get_name(rdev));
2754
2755         if (rdev->desc->off_on_delay) {
2756                 /* if needed, keep a distance of off_on_delay from last time
2757                  * this regulator was disabled.
2758                  */
2759                 ktime_t end = ktime_add_us(rdev->last_off, rdev->desc->off_on_delay);
2760                 s64 remaining = ktime_us_delta(end, ktime_get_boottime());
2761
2762                 if (remaining > 0)
2763                         _regulator_delay_helper(remaining);
2764         }
2765
2766         if (rdev->ena_pin) {
2767                 if (!rdev->ena_gpio_state) {
2768                         ret = regulator_ena_gpio_ctrl(rdev, true);
2769                         if (ret < 0)
2770                                 return ret;
2771                         rdev->ena_gpio_state = 1;
2772                 }
2773         } else if (rdev->desc->ops->enable) {
2774                 ret = rdev->desc->ops->enable(rdev);
2775                 if (ret < 0)
2776                         return ret;
2777         } else {
2778                 return -EINVAL;
2779         }
2780
2781         /* Allow the regulator to ramp; it would be useful to extend
2782          * this for bulk operations so that the regulators can ramp
2783          * together.
2784          */
2785         trace_regulator_enable_delay(rdev_get_name(rdev));
2786
2787         /* If poll_enabled_time is set, poll upto the delay calculated
2788          * above, delaying poll_enabled_time uS to check if the regulator
2789          * actually got enabled.
2790          * If the regulator isn't enabled after our delay helper has expired,
2791          * return -ETIMEDOUT.
2792          */
2793         if (rdev->desc->poll_enabled_time) {
2794                 int time_remaining = delay;
2795
2796                 while (time_remaining > 0) {
2797                         _regulator_delay_helper(rdev->desc->poll_enabled_time);
2798
2799                         if (rdev->desc->ops->get_status) {
2800                                 ret = _regulator_check_status_enabled(rdev);
2801                                 if (ret < 0)
2802                                         return ret;
2803                                 else if (ret)
2804                                         break;
2805                         } else if (rdev->desc->ops->is_enabled(rdev))
2806                                 break;
2807
2808                         time_remaining -= rdev->desc->poll_enabled_time;
2809                 }
2810
2811                 if (time_remaining <= 0) {
2812                         rdev_err(rdev, "Enabled check timed out\n");
2813                         return -ETIMEDOUT;
2814                 }
2815         } else {
2816                 _regulator_delay_helper(delay);
2817         }
2818
2819         trace_regulator_enable_complete(rdev_get_name(rdev));
2820
2821         return 0;
2822 }
2823
2824 /**
2825  * _regulator_handle_consumer_enable - handle that a consumer enabled
2826  * @regulator: regulator source
2827  *
2828  * Some things on a regulator consumer (like the contribution towards total
2829  * load on the regulator) only have an effect when the consumer wants the
2830  * regulator enabled.  Explained in example with two consumers of the same
2831  * regulator:
2832  *   consumer A: set_load(100);       => total load = 0
2833  *   consumer A: regulator_enable();  => total load = 100
2834  *   consumer B: set_load(1000);      => total load = 100
2835  *   consumer B: regulator_enable();  => total load = 1100
2836  *   consumer A: regulator_disable(); => total_load = 1000
2837  *
2838  * This function (together with _regulator_handle_consumer_disable) is
2839  * responsible for keeping track of the refcount for a given regulator consumer
2840  * and applying / unapplying these things.
2841  *
2842  * Returns 0 upon no error; -error upon error.
2843  */
2844 static int _regulator_handle_consumer_enable(struct regulator *regulator)
2845 {
2846         int ret;
2847         struct regulator_dev *rdev = regulator->rdev;
2848
2849         lockdep_assert_held_once(&rdev->mutex.base);
2850
2851         regulator->enable_count++;
2852         if (regulator->uA_load && regulator->enable_count == 1) {
2853                 ret = drms_uA_update(rdev);
2854                 if (ret)
2855                         regulator->enable_count--;
2856                 return ret;
2857         }
2858
2859         return 0;
2860 }
2861
2862 /**
2863  * _regulator_handle_consumer_disable - handle that a consumer disabled
2864  * @regulator: regulator source
2865  *
2866  * The opposite of _regulator_handle_consumer_enable().
2867  *
2868  * Returns 0 upon no error; -error upon error.
2869  */
2870 static int _regulator_handle_consumer_disable(struct regulator *regulator)
2871 {
2872         struct regulator_dev *rdev = regulator->rdev;
2873
2874         lockdep_assert_held_once(&rdev->mutex.base);
2875
2876         if (!regulator->enable_count) {
2877                 rdev_err(rdev, "Underflow of regulator enable count\n");
2878                 return -EINVAL;
2879         }
2880
2881         regulator->enable_count--;
2882         if (regulator->uA_load && regulator->enable_count == 0)
2883                 return drms_uA_update(rdev);
2884
2885         return 0;
2886 }
2887
2888 /* locks held by regulator_enable() */
2889 static int _regulator_enable(struct regulator *regulator)
2890 {
2891         struct regulator_dev *rdev = regulator->rdev;
2892         int ret;
2893
2894         lockdep_assert_held_once(&rdev->mutex.base);
2895
2896         if (rdev->use_count == 0 && rdev->supply) {
2897                 ret = _regulator_enable(rdev->supply);
2898                 if (ret < 0)
2899                         return ret;
2900         }
2901
2902         /* balance only if there are regulators coupled */
2903         if (rdev->coupling_desc.n_coupled > 1) {
2904                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2905                 if (ret < 0)
2906                         goto err_disable_supply;
2907         }
2908
2909         ret = _regulator_handle_consumer_enable(regulator);
2910         if (ret < 0)
2911                 goto err_disable_supply;
2912
2913         if (rdev->use_count == 0) {
2914                 /*
2915                  * The regulator may already be enabled if it's not switchable
2916                  * or was left on
2917                  */
2918                 ret = _regulator_is_enabled(rdev);
2919                 if (ret == -EINVAL || ret == 0) {
2920                         if (!regulator_ops_is_valid(rdev,
2921                                         REGULATOR_CHANGE_STATUS)) {
2922                                 ret = -EPERM;
2923                                 goto err_consumer_disable;
2924                         }
2925
2926                         ret = _regulator_do_enable(rdev);
2927                         if (ret < 0)
2928                                 goto err_consumer_disable;
2929
2930                         _notifier_call_chain(rdev, REGULATOR_EVENT_ENABLE,
2931                                              NULL);
2932                 } else if (ret < 0) {
2933                         rdev_err(rdev, "is_enabled() failed: %pe\n", ERR_PTR(ret));
2934                         goto err_consumer_disable;
2935                 }
2936                 /* Fallthrough on positive return values - already enabled */
2937         }
2938
2939         if (regulator->enable_count == 1)
2940                 rdev->use_count++;
2941
2942         return 0;
2943
2944 err_consumer_disable:
2945         _regulator_handle_consumer_disable(regulator);
2946
2947 err_disable_supply:
2948         if (rdev->use_count == 0 && rdev->supply)
2949                 _regulator_disable(rdev->supply);
2950
2951         return ret;
2952 }
2953
2954 /**
2955  * regulator_enable - enable regulator output
2956  * @regulator: regulator source
2957  *
2958  * Request that the regulator be enabled with the regulator output at
2959  * the predefined voltage or current value.  Calls to regulator_enable()
2960  * must be balanced with calls to regulator_disable().
2961  *
2962  * NOTE: the output value can be set by other drivers, boot loader or may be
2963  * hardwired in the regulator.
2964  */
2965 int regulator_enable(struct regulator *regulator)
2966 {
2967         struct regulator_dev *rdev = regulator->rdev;
2968         struct ww_acquire_ctx ww_ctx;
2969         int ret;
2970
2971         regulator_lock_dependent(rdev, &ww_ctx);
2972         ret = _regulator_enable(regulator);
2973         regulator_unlock_dependent(rdev, &ww_ctx);
2974
2975         return ret;
2976 }
2977 EXPORT_SYMBOL_GPL(regulator_enable);
2978
2979 static int _regulator_do_disable(struct regulator_dev *rdev)
2980 {
2981         int ret;
2982
2983         trace_regulator_disable(rdev_get_name(rdev));
2984
2985         if (rdev->ena_pin) {
2986                 if (rdev->ena_gpio_state) {
2987                         ret = regulator_ena_gpio_ctrl(rdev, false);
2988                         if (ret < 0)
2989                                 return ret;
2990                         rdev->ena_gpio_state = 0;
2991                 }
2992
2993         } else if (rdev->desc->ops->disable) {
2994                 ret = rdev->desc->ops->disable(rdev);
2995                 if (ret != 0)
2996                         return ret;
2997         }
2998
2999         if (rdev->desc->off_on_delay)
3000                 rdev->last_off = ktime_get_boottime();
3001
3002         trace_regulator_disable_complete(rdev_get_name(rdev));
3003
3004         return 0;
3005 }
3006
3007 /* locks held by regulator_disable() */
3008 static int _regulator_disable(struct regulator *regulator)
3009 {
3010         struct regulator_dev *rdev = regulator->rdev;
3011         int ret = 0;
3012
3013         lockdep_assert_held_once(&rdev->mutex.base);
3014
3015         if (WARN(regulator->enable_count == 0,
3016                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
3017                 return -EIO;
3018
3019         if (regulator->enable_count == 1) {
3020         /* disabling last enable_count from this regulator */
3021                 /* are we the last user and permitted to disable ? */
3022                 if (rdev->use_count == 1 &&
3023                     (rdev->constraints && !rdev->constraints->always_on)) {
3024
3025                         /* we are last user */
3026                         if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
3027                                 ret = _notifier_call_chain(rdev,
3028                                                            REGULATOR_EVENT_PRE_DISABLE,
3029                                                            NULL);
3030                                 if (ret & NOTIFY_STOP_MASK)
3031                                         return -EINVAL;
3032
3033                                 ret = _regulator_do_disable(rdev);
3034                                 if (ret < 0) {
3035                                         rdev_err(rdev, "failed to disable: %pe\n", ERR_PTR(ret));
3036                                         _notifier_call_chain(rdev,
3037                                                         REGULATOR_EVENT_ABORT_DISABLE,
3038                                                         NULL);
3039                                         return ret;
3040                                 }
3041                                 _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
3042                                                 NULL);
3043                         }
3044
3045                         rdev->use_count = 0;
3046                 } else if (rdev->use_count > 1) {
3047                         rdev->use_count--;
3048                 }
3049         }
3050
3051         if (ret == 0)
3052                 ret = _regulator_handle_consumer_disable(regulator);
3053
3054         if (ret == 0 && rdev->coupling_desc.n_coupled > 1)
3055                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3056
3057         if (ret == 0 && rdev->use_count == 0 && rdev->supply)
3058                 ret = _regulator_disable(rdev->supply);
3059
3060         return ret;
3061 }
3062
3063 /**
3064  * regulator_disable - disable regulator output
3065  * @regulator: regulator source
3066  *
3067  * Disable the regulator output voltage or current.  Calls to
3068  * regulator_enable() must be balanced with calls to
3069  * regulator_disable().
3070  *
3071  * NOTE: this will only disable the regulator output if no other consumer
3072  * devices have it enabled, the regulator device supports disabling and
3073  * machine constraints permit this operation.
3074  */
3075 int regulator_disable(struct regulator *regulator)
3076 {
3077         struct regulator_dev *rdev = regulator->rdev;
3078         struct ww_acquire_ctx ww_ctx;
3079         int ret;
3080
3081         regulator_lock_dependent(rdev, &ww_ctx);
3082         ret = _regulator_disable(regulator);
3083         regulator_unlock_dependent(rdev, &ww_ctx);
3084
3085         return ret;
3086 }
3087 EXPORT_SYMBOL_GPL(regulator_disable);
3088
3089 /* locks held by regulator_force_disable() */
3090 static int _regulator_force_disable(struct regulator_dev *rdev)
3091 {
3092         int ret = 0;
3093
3094         lockdep_assert_held_once(&rdev->mutex.base);
3095
3096         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3097                         REGULATOR_EVENT_PRE_DISABLE, NULL);
3098         if (ret & NOTIFY_STOP_MASK)
3099                 return -EINVAL;
3100
3101         ret = _regulator_do_disable(rdev);
3102         if (ret < 0) {
3103                 rdev_err(rdev, "failed to force disable: %pe\n", ERR_PTR(ret));
3104                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3105                                 REGULATOR_EVENT_ABORT_DISABLE, NULL);
3106                 return ret;
3107         }
3108
3109         _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3110                         REGULATOR_EVENT_DISABLE, NULL);
3111
3112         return 0;
3113 }
3114
3115 /**
3116  * regulator_force_disable - force disable regulator output
3117  * @regulator: regulator source
3118  *
3119  * Forcibly disable the regulator output voltage or current.
3120  * NOTE: this *will* disable the regulator output even if other consumer
3121  * devices have it enabled. This should be used for situations when device
3122  * damage will likely occur if the regulator is not disabled (e.g. over temp).
3123  */
3124 int regulator_force_disable(struct regulator *regulator)
3125 {
3126         struct regulator_dev *rdev = regulator->rdev;
3127         struct ww_acquire_ctx ww_ctx;
3128         int ret;
3129
3130         regulator_lock_dependent(rdev, &ww_ctx);
3131
3132         ret = _regulator_force_disable(regulator->rdev);
3133
3134         if (rdev->coupling_desc.n_coupled > 1)
3135                 regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3136
3137         if (regulator->uA_load) {
3138                 regulator->uA_load = 0;
3139                 ret = drms_uA_update(rdev);
3140         }
3141
3142         if (rdev->use_count != 0 && rdev->supply)
3143                 _regulator_disable(rdev->supply);
3144
3145         regulator_unlock_dependent(rdev, &ww_ctx);
3146
3147         return ret;
3148 }
3149 EXPORT_SYMBOL_GPL(regulator_force_disable);
3150
3151 static void regulator_disable_work(struct work_struct *work)
3152 {
3153         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
3154                                                   disable_work.work);
3155         struct ww_acquire_ctx ww_ctx;
3156         int count, i, ret;
3157         struct regulator *regulator;
3158         int total_count = 0;
3159
3160         regulator_lock_dependent(rdev, &ww_ctx);
3161
3162         /*
3163          * Workqueue functions queue the new work instance while the previous
3164          * work instance is being processed. Cancel the queued work instance
3165          * as the work instance under processing does the job of the queued
3166          * work instance.
3167          */
3168         cancel_delayed_work(&rdev->disable_work);
3169
3170         list_for_each_entry(regulator, &rdev->consumer_list, list) {
3171                 count = regulator->deferred_disables;
3172
3173                 if (!count)
3174                         continue;
3175
3176                 total_count += count;
3177                 regulator->deferred_disables = 0;
3178
3179                 for (i = 0; i < count; i++) {
3180                         ret = _regulator_disable(regulator);
3181                         if (ret != 0)
3182                                 rdev_err(rdev, "Deferred disable failed: %pe\n",
3183                                          ERR_PTR(ret));
3184                 }
3185         }
3186         WARN_ON(!total_count);
3187
3188         if (rdev->coupling_desc.n_coupled > 1)
3189                 regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3190
3191         regulator_unlock_dependent(rdev, &ww_ctx);
3192 }
3193
3194 /**
3195  * regulator_disable_deferred - disable regulator output with delay
3196  * @regulator: regulator source
3197  * @ms: milliseconds until the regulator is disabled
3198  *
3199  * Execute regulator_disable() on the regulator after a delay.  This
3200  * is intended for use with devices that require some time to quiesce.
3201  *
3202  * NOTE: this will only disable the regulator output if no other consumer
3203  * devices have it enabled, the regulator device supports disabling and
3204  * machine constraints permit this operation.
3205  */
3206 int regulator_disable_deferred(struct regulator *regulator, int ms)
3207 {
3208         struct regulator_dev *rdev = regulator->rdev;
3209
3210         if (!ms)
3211                 return regulator_disable(regulator);
3212
3213         regulator_lock(rdev);
3214         regulator->deferred_disables++;
3215         mod_delayed_work(system_power_efficient_wq, &rdev->disable_work,
3216                          msecs_to_jiffies(ms));
3217         regulator_unlock(rdev);
3218
3219         return 0;
3220 }
3221 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
3222
3223 static int _regulator_is_enabled(struct regulator_dev *rdev)
3224 {
3225         /* A GPIO control always takes precedence */
3226         if (rdev->ena_pin)
3227                 return rdev->ena_gpio_state;
3228
3229         /* If we don't know then assume that the regulator is always on */
3230         if (!rdev->desc->ops->is_enabled)
3231                 return 1;
3232
3233         return rdev->desc->ops->is_enabled(rdev);
3234 }
3235
3236 static int _regulator_list_voltage(struct regulator_dev *rdev,
3237                                    unsigned selector, int lock)
3238 {
3239         const struct regulator_ops *ops = rdev->desc->ops;
3240         int ret;
3241
3242         if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
3243                 return rdev->desc->fixed_uV;
3244
3245         if (ops->list_voltage) {
3246                 if (selector >= rdev->desc->n_voltages)
3247                         return -EINVAL;
3248                 if (selector < rdev->desc->linear_min_sel)
3249                         return 0;
3250                 if (lock)
3251                         regulator_lock(rdev);
3252                 ret = ops->list_voltage(rdev, selector);
3253                 if (lock)
3254                         regulator_unlock(rdev);
3255         } else if (rdev->is_switch && rdev->supply) {
3256                 ret = _regulator_list_voltage(rdev->supply->rdev,
3257                                               selector, lock);
3258         } else {
3259                 return -EINVAL;
3260         }
3261
3262         if (ret > 0) {
3263                 if (ret < rdev->constraints->min_uV)
3264                         ret = 0;
3265                 else if (ret > rdev->constraints->max_uV)
3266                         ret = 0;
3267         }
3268
3269         return ret;
3270 }
3271
3272 /**
3273  * regulator_is_enabled - is the regulator output enabled
3274  * @regulator: regulator source
3275  *
3276  * Returns positive if the regulator driver backing the source/client
3277  * has requested that the device be enabled, zero if it hasn't, else a
3278  * negative errno code.
3279  *
3280  * Note that the device backing this regulator handle can have multiple
3281  * users, so it might be enabled even if regulator_enable() was never
3282  * called for this particular source.
3283  */
3284 int regulator_is_enabled(struct regulator *regulator)
3285 {
3286         int ret;
3287
3288         if (regulator->always_on)
3289                 return 1;
3290
3291         regulator_lock(regulator->rdev);
3292         ret = _regulator_is_enabled(regulator->rdev);
3293         regulator_unlock(regulator->rdev);
3294
3295         return ret;
3296 }
3297 EXPORT_SYMBOL_GPL(regulator_is_enabled);
3298
3299 /**
3300  * regulator_count_voltages - count regulator_list_voltage() selectors
3301  * @regulator: regulator source
3302  *
3303  * Returns number of selectors, or negative errno.  Selectors are
3304  * numbered starting at zero, and typically correspond to bitfields
3305  * in hardware registers.
3306  */
3307 int regulator_count_voltages(struct regulator *regulator)
3308 {
3309         struct regulator_dev    *rdev = regulator->rdev;
3310
3311         if (rdev->desc->n_voltages)
3312                 return rdev->desc->n_voltages;
3313
3314         if (!rdev->is_switch || !rdev->supply)
3315                 return -EINVAL;
3316
3317         return regulator_count_voltages(rdev->supply);
3318 }
3319 EXPORT_SYMBOL_GPL(regulator_count_voltages);
3320
3321 /**
3322  * regulator_list_voltage - enumerate supported voltages
3323  * @regulator: regulator source
3324  * @selector: identify voltage to list
3325  * Context: can sleep
3326  *
3327  * Returns a voltage that can be passed to @regulator_set_voltage(),
3328  * zero if this selector code can't be used on this system, or a
3329  * negative errno.
3330  */
3331 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
3332 {
3333         return _regulator_list_voltage(regulator->rdev, selector, 1);
3334 }
3335 EXPORT_SYMBOL_GPL(regulator_list_voltage);
3336
3337 /**
3338  * regulator_get_regmap - get the regulator's register map
3339  * @regulator: regulator source
3340  *
3341  * Returns the register map for the given regulator, or an ERR_PTR value
3342  * if the regulator doesn't use regmap.
3343  */
3344 struct regmap *regulator_get_regmap(struct regulator *regulator)
3345 {
3346         struct regmap *map = regulator->rdev->regmap;
3347
3348         return map ? map : ERR_PTR(-EOPNOTSUPP);
3349 }
3350
3351 /**
3352  * regulator_get_hardware_vsel_register - get the HW voltage selector register
3353  * @regulator: regulator source
3354  * @vsel_reg: voltage selector register, output parameter
3355  * @vsel_mask: mask for voltage selector bitfield, output parameter
3356  *
3357  * Returns the hardware register offset and bitmask used for setting the
3358  * regulator voltage. This might be useful when configuring voltage-scaling
3359  * hardware or firmware that can make I2C requests behind the kernel's back,
3360  * for example.
3361  *
3362  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
3363  * and 0 is returned, otherwise a negative errno is returned.
3364  */
3365 int regulator_get_hardware_vsel_register(struct regulator *regulator,
3366                                          unsigned *vsel_reg,
3367                                          unsigned *vsel_mask)
3368 {
3369         struct regulator_dev *rdev = regulator->rdev;
3370         const struct regulator_ops *ops = rdev->desc->ops;
3371
3372         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3373                 return -EOPNOTSUPP;
3374
3375         *vsel_reg = rdev->desc->vsel_reg;
3376         *vsel_mask = rdev->desc->vsel_mask;
3377
3378         return 0;
3379 }
3380 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
3381
3382 /**
3383  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
3384  * @regulator: regulator source
3385  * @selector: identify voltage to list
3386  *
3387  * Converts the selector to a hardware-specific voltage selector that can be
3388  * directly written to the regulator registers. The address of the voltage
3389  * register can be determined by calling @regulator_get_hardware_vsel_register.
3390  *
3391  * On error a negative errno is returned.
3392  */
3393 int regulator_list_hardware_vsel(struct regulator *regulator,
3394                                  unsigned selector)
3395 {
3396         struct regulator_dev *rdev = regulator->rdev;
3397         const struct regulator_ops *ops = rdev->desc->ops;
3398
3399         if (selector >= rdev->desc->n_voltages)
3400                 return -EINVAL;
3401         if (selector < rdev->desc->linear_min_sel)
3402                 return 0;
3403         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3404                 return -EOPNOTSUPP;
3405
3406         return selector;
3407 }
3408 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
3409
3410 /**
3411  * regulator_get_linear_step - return the voltage step size between VSEL values
3412  * @regulator: regulator source
3413  *
3414  * Returns the voltage step size between VSEL values for linear
3415  * regulators, or return 0 if the regulator isn't a linear regulator.
3416  */
3417 unsigned int regulator_get_linear_step(struct regulator *regulator)
3418 {
3419         struct regulator_dev *rdev = regulator->rdev;
3420
3421         return rdev->desc->uV_step;
3422 }
3423 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
3424
3425 /**
3426  * regulator_is_supported_voltage - check if a voltage range can be supported
3427  *
3428  * @regulator: Regulator to check.
3429  * @min_uV: Minimum required voltage in uV.
3430  * @max_uV: Maximum required voltage in uV.
3431  *
3432  * Returns a boolean.
3433  */
3434 int regulator_is_supported_voltage(struct regulator *regulator,
3435                                    int min_uV, int max_uV)
3436 {
3437         struct regulator_dev *rdev = regulator->rdev;
3438         int i, voltages, ret;
3439
3440         /* If we can't change voltage check the current voltage */
3441         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3442                 ret = regulator_get_voltage(regulator);
3443                 if (ret >= 0)
3444                         return min_uV <= ret && ret <= max_uV;
3445                 else
3446                         return ret;
3447         }
3448
3449         /* Any voltage within constrains range is fine? */
3450         if (rdev->desc->continuous_voltage_range)
3451                 return min_uV >= rdev->constraints->min_uV &&
3452                                 max_uV <= rdev->constraints->max_uV;
3453
3454         ret = regulator_count_voltages(regulator);
3455         if (ret < 0)
3456                 return 0;
3457         voltages = ret;
3458
3459         for (i = 0; i < voltages; i++) {
3460                 ret = regulator_list_voltage(regulator, i);
3461
3462                 if (ret >= min_uV && ret <= max_uV)
3463                         return 1;
3464         }
3465
3466         return 0;
3467 }
3468 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
3469
3470 static int regulator_map_voltage(struct regulator_dev *rdev, int min_uV,
3471                                  int max_uV)
3472 {
3473         const struct regulator_desc *desc = rdev->desc;
3474
3475         if (desc->ops->map_voltage)
3476                 return desc->ops->map_voltage(rdev, min_uV, max_uV);
3477
3478         if (desc->ops->list_voltage == regulator_list_voltage_linear)
3479                 return regulator_map_voltage_linear(rdev, min_uV, max_uV);
3480
3481         if (desc->ops->list_voltage == regulator_list_voltage_linear_range)
3482                 return regulator_map_voltage_linear_range(rdev, min_uV, max_uV);
3483
3484         if (desc->ops->list_voltage ==
3485                 regulator_list_voltage_pickable_linear_range)
3486                 return regulator_map_voltage_pickable_linear_range(rdev,
3487                                                         min_uV, max_uV);
3488
3489         return regulator_map_voltage_iterate(rdev, min_uV, max_uV);
3490 }
3491
3492 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
3493                                        int min_uV, int max_uV,
3494                                        unsigned *selector)
3495 {
3496         struct pre_voltage_change_data data;
3497         int ret;
3498
3499         data.old_uV = regulator_get_voltage_rdev(rdev);
3500         data.min_uV = min_uV;
3501         data.max_uV = max_uV;
3502         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3503                                    &data);
3504         if (ret & NOTIFY_STOP_MASK)
3505                 return -EINVAL;
3506
3507         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
3508         if (ret >= 0)
3509                 return ret;
3510
3511         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3512                              (void *)data.old_uV);
3513
3514         return ret;
3515 }
3516
3517 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
3518                                            int uV, unsigned selector)
3519 {
3520         struct pre_voltage_change_data data;
3521         int ret;
3522
3523         data.old_uV = regulator_get_voltage_rdev(rdev);
3524         data.min_uV = uV;
3525         data.max_uV = uV;
3526         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3527                                    &data);
3528         if (ret & NOTIFY_STOP_MASK)
3529                 return -EINVAL;
3530
3531         ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
3532         if (ret >= 0)
3533                 return ret;
3534
3535         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3536                              (void *)data.old_uV);
3537
3538         return ret;
3539 }
3540
3541 static int _regulator_set_voltage_sel_step(struct regulator_dev *rdev,
3542                                            int uV, int new_selector)
3543 {
3544         const struct regulator_ops *ops = rdev->desc->ops;
3545         int diff, old_sel, curr_sel, ret;
3546
3547         /* Stepping is only needed if the regulator is enabled. */
3548         if (!_regulator_is_enabled(rdev))
3549                 goto final_set;
3550
3551         if (!ops->get_voltage_sel)
3552                 return -EINVAL;
3553
3554         old_sel = ops->get_voltage_sel(rdev);
3555         if (old_sel < 0)
3556                 return old_sel;
3557
3558         diff = new_selector - old_sel;
3559         if (diff == 0)
3560                 return 0; /* No change needed. */
3561
3562         if (diff > 0) {
3563                 /* Stepping up. */
3564                 for (curr_sel = old_sel + rdev->desc->vsel_step;
3565                      curr_sel < new_selector;
3566                      curr_sel += rdev->desc->vsel_step) {
3567                         /*
3568                          * Call the callback directly instead of using
3569                          * _regulator_call_set_voltage_sel() as we don't
3570                          * want to notify anyone yet. Same in the branch
3571                          * below.
3572                          */
3573                         ret = ops->set_voltage_sel(rdev, curr_sel);
3574                         if (ret)
3575                                 goto try_revert;
3576                 }
3577         } else {
3578                 /* Stepping down. */
3579                 for (curr_sel = old_sel - rdev->desc->vsel_step;
3580                      curr_sel > new_selector;
3581                      curr_sel -= rdev->desc->vsel_step) {
3582                         ret = ops->set_voltage_sel(rdev, curr_sel);
3583                         if (ret)
3584                                 goto try_revert;
3585                 }
3586         }
3587
3588 final_set:
3589         /* The final selector will trigger the notifiers. */
3590         return _regulator_call_set_voltage_sel(rdev, uV, new_selector);
3591
3592 try_revert:
3593         /*
3594          * At least try to return to the previous voltage if setting a new
3595          * one failed.
3596          */
3597         (void)ops->set_voltage_sel(rdev, old_sel);
3598         return ret;
3599 }
3600
3601 static int _regulator_set_voltage_time(struct regulator_dev *rdev,
3602                                        int old_uV, int new_uV)
3603 {
3604         unsigned int ramp_delay = 0;
3605
3606         if (rdev->constraints->ramp_delay)
3607                 ramp_delay = rdev->constraints->ramp_delay;
3608         else if (rdev->desc->ramp_delay)
3609                 ramp_delay = rdev->desc->ramp_delay;
3610         else if (rdev->constraints->settling_time)
3611                 return rdev->constraints->settling_time;
3612         else if (rdev->constraints->settling_time_up &&
3613                  (new_uV > old_uV))
3614                 return rdev->constraints->settling_time_up;
3615         else if (rdev->constraints->settling_time_down &&
3616                  (new_uV < old_uV))
3617                 return rdev->constraints->settling_time_down;
3618
3619         if (ramp_delay == 0)
3620                 return 0;
3621
3622         return DIV_ROUND_UP(abs(new_uV - old_uV), ramp_delay);
3623 }
3624
3625 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
3626                                      int min_uV, int max_uV)
3627 {
3628         int ret;
3629         int delay = 0;
3630         int best_val = 0;
3631         unsigned int selector;
3632         int old_selector = -1;
3633         const struct regulator_ops *ops = rdev->desc->ops;
3634         int old_uV = regulator_get_voltage_rdev(rdev);
3635
3636         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
3637
3638         min_uV += rdev->constraints->uV_offset;
3639         max_uV += rdev->constraints->uV_offset;
3640
3641         /*
3642          * If we can't obtain the old selector there is not enough
3643          * info to call set_voltage_time_sel().
3644          */
3645         if (_regulator_is_enabled(rdev) &&
3646             ops->set_voltage_time_sel && ops->get_voltage_sel) {
3647                 old_selector = ops->get_voltage_sel(rdev);
3648                 if (old_selector < 0)
3649                         return old_selector;
3650         }
3651
3652         if (ops->set_voltage) {
3653                 ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
3654                                                   &selector);
3655
3656                 if (ret >= 0) {
3657                         if (ops->list_voltage)
3658                                 best_val = ops->list_voltage(rdev,
3659                                                              selector);
3660                         else
3661                                 best_val = regulator_get_voltage_rdev(rdev);
3662                 }
3663
3664         } else if (ops->set_voltage_sel) {
3665                 ret = regulator_map_voltage(rdev, min_uV, max_uV);
3666                 if (ret >= 0) {
3667                         best_val = ops->list_voltage(rdev, ret);
3668                         if (min_uV <= best_val && max_uV >= best_val) {
3669                                 selector = ret;
3670                                 if (old_selector == selector)
3671                                         ret = 0;
3672                                 else if (rdev->desc->vsel_step)
3673                                         ret = _regulator_set_voltage_sel_step(
3674                                                 rdev, best_val, selector);
3675                                 else
3676                                         ret = _regulator_call_set_voltage_sel(
3677                                                 rdev, best_val, selector);
3678                         } else {
3679                                 ret = -EINVAL;
3680                         }
3681                 }
3682         } else {
3683                 ret = -EINVAL;
3684         }
3685
3686         if (ret)
3687                 goto out;
3688
3689         if (ops->set_voltage_time_sel) {
3690                 /*
3691                  * Call set_voltage_time_sel if successfully obtained
3692                  * old_selector
3693                  */
3694                 if (old_selector >= 0 && old_selector != selector)
3695                         delay = ops->set_voltage_time_sel(rdev, old_selector,
3696                                                           selector);
3697         } else {
3698                 if (old_uV != best_val) {
3699                         if (ops->set_voltage_time)
3700                                 delay = ops->set_voltage_time(rdev, old_uV,
3701                                                               best_val);
3702                         else
3703                                 delay = _regulator_set_voltage_time(rdev,
3704                                                                     old_uV,
3705                                                                     best_val);
3706                 }
3707         }
3708
3709         if (delay < 0) {
3710                 rdev_warn(rdev, "failed to get delay: %pe\n", ERR_PTR(delay));
3711                 delay = 0;
3712         }
3713
3714         /* Insert any necessary delays */
3715         _regulator_delay_helper(delay);
3716
3717         if (best_val >= 0) {
3718                 unsigned long data = best_val;
3719
3720                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
3721                                      (void *)data);
3722         }
3723
3724 out:
3725         trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
3726
3727         return ret;
3728 }
3729
3730 static int _regulator_do_set_suspend_voltage(struct regulator_dev *rdev,
3731                                   int min_uV, int max_uV, suspend_state_t state)
3732 {
3733         struct regulator_state *rstate;
3734         int uV, sel;
3735
3736         rstate = regulator_get_suspend_state(rdev, state);
3737         if (rstate == NULL)
3738                 return -EINVAL;
3739
3740         if (min_uV < rstate->min_uV)
3741                 min_uV = rstate->min_uV;
3742         if (max_uV > rstate->max_uV)
3743                 max_uV = rstate->max_uV;
3744
3745         sel = regulator_map_voltage(rdev, min_uV, max_uV);
3746         if (sel < 0)
3747                 return sel;
3748
3749         uV = rdev->desc->ops->list_voltage(rdev, sel);
3750         if (uV >= min_uV && uV <= max_uV)
3751                 rstate->uV = uV;
3752
3753         return 0;
3754 }
3755
3756 static int regulator_set_voltage_unlocked(struct regulator *regulator,
3757                                           int min_uV, int max_uV,
3758                                           suspend_state_t state)
3759 {
3760         struct regulator_dev *rdev = regulator->rdev;
3761         struct regulator_voltage *voltage = &regulator->voltage[state];
3762         int ret = 0;
3763         int old_min_uV, old_max_uV;
3764         int current_uV;
3765
3766         /* If we're setting the same range as last time the change
3767          * should be a noop (some cpufreq implementations use the same
3768          * voltage for multiple frequencies, for example).
3769          */
3770         if (voltage->min_uV == min_uV && voltage->max_uV == max_uV)
3771                 goto out;
3772
3773         /* If we're trying to set a range that overlaps the current voltage,
3774          * return successfully even though the regulator does not support
3775          * changing the voltage.
3776          */
3777         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3778                 current_uV = regulator_get_voltage_rdev(rdev);
3779                 if (min_uV <= current_uV && current_uV <= max_uV) {
3780                         voltage->min_uV = min_uV;
3781                         voltage->max_uV = max_uV;
3782                         goto out;
3783                 }
3784         }
3785
3786         /* sanity check */
3787         if (!rdev->desc->ops->set_voltage &&
3788             !rdev->desc->ops->set_voltage_sel) {
3789                 ret = -EINVAL;
3790                 goto out;
3791         }
3792
3793         /* constraints check */
3794         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
3795         if (ret < 0)
3796                 goto out;
3797
3798         /* restore original values in case of error */
3799         old_min_uV = voltage->min_uV;
3800         old_max_uV = voltage->max_uV;
3801         voltage->min_uV = min_uV;
3802         voltage->max_uV = max_uV;
3803
3804         /* for not coupled regulators this will just set the voltage */
3805         ret = regulator_balance_voltage(rdev, state);
3806         if (ret < 0) {
3807                 voltage->min_uV = old_min_uV;
3808                 voltage->max_uV = old_max_uV;
3809         }
3810
3811 out:
3812         return ret;
3813 }
3814
3815 int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
3816                                int max_uV, suspend_state_t state)
3817 {
3818         int best_supply_uV = 0;
3819         int supply_change_uV = 0;
3820         int ret;
3821
3822         if (rdev->supply &&
3823             regulator_ops_is_valid(rdev->supply->rdev,
3824                                    REGULATOR_CHANGE_VOLTAGE) &&
3825             (rdev->desc->min_dropout_uV || !(rdev->desc->ops->get_voltage ||
3826                                            rdev->desc->ops->get_voltage_sel))) {
3827                 int current_supply_uV;
3828                 int selector;
3829
3830                 selector = regulator_map_voltage(rdev, min_uV, max_uV);
3831                 if (selector < 0) {
3832                         ret = selector;
3833                         goto out;
3834                 }
3835
3836                 best_supply_uV = _regulator_list_voltage(rdev, selector, 0);
3837                 if (best_supply_uV < 0) {
3838                         ret = best_supply_uV;
3839                         goto out;
3840                 }
3841
3842                 best_supply_uV += rdev->desc->min_dropout_uV;
3843
3844                 current_supply_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
3845                 if (current_supply_uV < 0) {
3846                         ret = current_supply_uV;
3847                         goto out;
3848                 }
3849
3850                 supply_change_uV = best_supply_uV - current_supply_uV;
3851         }
3852
3853         if (supply_change_uV > 0) {
3854                 ret = regulator_set_voltage_unlocked(rdev->supply,
3855                                 best_supply_uV, INT_MAX, state);
3856                 if (ret) {
3857                         dev_err(&rdev->dev, "Failed to increase supply voltage: %pe\n",
3858                                 ERR_PTR(ret));
3859                         goto out;
3860                 }
3861         }
3862
3863         if (state == PM_SUSPEND_ON)
3864                 ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
3865         else
3866                 ret = _regulator_do_set_suspend_voltage(rdev, min_uV,
3867                                                         max_uV, state);
3868         if (ret < 0)
3869                 goto out;
3870
3871         if (supply_change_uV < 0) {
3872                 ret = regulator_set_voltage_unlocked(rdev->supply,
3873                                 best_supply_uV, INT_MAX, state);
3874                 if (ret)
3875                         dev_warn(&rdev->dev, "Failed to decrease supply voltage: %pe\n",
3876                                  ERR_PTR(ret));
3877                 /* No need to fail here */
3878                 ret = 0;
3879         }
3880
3881 out:
3882         return ret;
3883 }
3884 EXPORT_SYMBOL_GPL(regulator_set_voltage_rdev);
3885
3886 static int regulator_limit_voltage_step(struct regulator_dev *rdev,
3887                                         int *current_uV, int *min_uV)
3888 {
3889         struct regulation_constraints *constraints = rdev->constraints;
3890
3891         /* Limit voltage change only if necessary */
3892         if (!constraints->max_uV_step || !_regulator_is_enabled(rdev))
3893                 return 1;
3894
3895         if (*current_uV < 0) {
3896                 *current_uV = regulator_get_voltage_rdev(rdev);
3897
3898                 if (*current_uV < 0)
3899                         return *current_uV;
3900         }
3901
3902         if (abs(*current_uV - *min_uV) <= constraints->max_uV_step)
3903                 return 1;
3904
3905         /* Clamp target voltage within the given step */
3906         if (*current_uV < *min_uV)
3907                 *min_uV = min(*current_uV + constraints->max_uV_step,
3908                               *min_uV);
3909         else
3910                 *min_uV = max(*current_uV - constraints->max_uV_step,
3911                               *min_uV);
3912
3913         return 0;
3914 }
3915
3916 static int regulator_get_optimal_voltage(struct regulator_dev *rdev,
3917                                          int *current_uV,
3918                                          int *min_uV, int *max_uV,
3919                                          suspend_state_t state,
3920                                          int n_coupled)
3921 {
3922         struct coupling_desc *c_desc = &rdev->coupling_desc;
3923         struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
3924         struct regulation_constraints *constraints = rdev->constraints;
3925         int desired_min_uV = 0, desired_max_uV = INT_MAX;
3926         int max_current_uV = 0, min_current_uV = INT_MAX;
3927         int highest_min_uV = 0, target_uV, possible_uV;
3928         int i, ret, max_spread;
3929         bool done;
3930
3931         *current_uV = -1;
3932
3933         /*
3934          * If there are no coupled regulators, simply set the voltage
3935          * demanded by consumers.
3936          */
3937         if (n_coupled == 1) {
3938                 /*
3939                  * If consumers don't provide any demands, set voltage
3940                  * to min_uV
3941                  */
3942                 desired_min_uV = constraints->min_uV;
3943                 desired_max_uV = constraints->max_uV;
3944
3945                 ret = regulator_check_consumers(rdev,
3946                                                 &desired_min_uV,
3947                                                 &desired_max_uV, state);
3948                 if (ret < 0)
3949                         return ret;
3950
3951                 done = true;
3952
3953                 goto finish;
3954         }
3955
3956         /* Find highest min desired voltage */
3957         for (i = 0; i < n_coupled; i++) {
3958                 int tmp_min = 0;
3959                 int tmp_max = INT_MAX;
3960
3961                 lockdep_assert_held_once(&c_rdevs[i]->mutex.base);
3962
3963                 ret = regulator_check_consumers(c_rdevs[i],
3964                                                 &tmp_min,
3965                                                 &tmp_max, state);
3966                 if (ret < 0)
3967                         return ret;
3968
3969                 ret = regulator_check_voltage(c_rdevs[i], &tmp_min, &tmp_max);
3970                 if (ret < 0)
3971                         return ret;
3972
3973                 highest_min_uV = max(highest_min_uV, tmp_min);
3974
3975                 if (i == 0) {
3976                         desired_min_uV = tmp_min;
3977                         desired_max_uV = tmp_max;
3978                 }
3979         }
3980
3981         max_spread = constraints->max_spread[0];
3982
3983         /*
3984          * Let target_uV be equal to the desired one if possible.
3985          * If not, set it to minimum voltage, allowed by other coupled
3986          * regulators.
3987          */
3988         target_uV = max(desired_min_uV, highest_min_uV - max_spread);
3989
3990         /*
3991          * Find min and max voltages, which currently aren't violating
3992          * max_spread.
3993          */
3994         for (i = 1; i < n_coupled; i++) {
3995                 int tmp_act;
3996
3997                 if (!_regulator_is_enabled(c_rdevs[i]))
3998                         continue;
3999
4000                 tmp_act = regulator_get_voltage_rdev(c_rdevs[i]);
4001                 if (tmp_act < 0)
4002                         return tmp_act;
4003
4004                 min_current_uV = min(tmp_act, min_current_uV);
4005                 max_current_uV = max(tmp_act, max_current_uV);
4006         }
4007
4008         /* There aren't any other regulators enabled */
4009         if (max_current_uV == 0) {
4010                 possible_uV = target_uV;
4011         } else {
4012                 /*
4013                  * Correct target voltage, so as it currently isn't
4014                  * violating max_spread
4015                  */
4016                 possible_uV = max(target_uV, max_current_uV - max_spread);
4017                 possible_uV = min(possible_uV, min_current_uV + max_spread);
4018         }
4019
4020         if (possible_uV > desired_max_uV)
4021                 return -EINVAL;
4022
4023         done = (possible_uV == target_uV);
4024         desired_min_uV = possible_uV;
4025
4026 finish:
4027         /* Apply max_uV_step constraint if necessary */
4028         if (state == PM_SUSPEND_ON) {
4029                 ret = regulator_limit_voltage_step(rdev, current_uV,
4030                                                    &desired_min_uV);
4031                 if (ret < 0)
4032                         return ret;
4033
4034                 if (ret == 0)
4035                         done = false;
4036         }
4037
4038         /* Set current_uV if wasn't done earlier in the code and if necessary */
4039         if (n_coupled > 1 && *current_uV == -1) {
4040
4041                 if (_regulator_is_enabled(rdev)) {
4042                         ret = regulator_get_voltage_rdev(rdev);
4043                         if (ret < 0)
4044                                 return ret;
4045
4046                         *current_uV = ret;
4047                 } else {
4048                         *current_uV = desired_min_uV;
4049                 }
4050         }
4051
4052         *min_uV = desired_min_uV;
4053         *max_uV = desired_max_uV;
4054
4055         return done;
4056 }
4057
4058 int regulator_do_balance_voltage(struct regulator_dev *rdev,
4059                                  suspend_state_t state, bool skip_coupled)
4060 {
4061         struct regulator_dev **c_rdevs;
4062         struct regulator_dev *best_rdev;
4063         struct coupling_desc *c_desc = &rdev->coupling_desc;
4064         int i, ret, n_coupled, best_min_uV, best_max_uV, best_c_rdev;
4065         unsigned int delta, best_delta;
4066         unsigned long c_rdev_done = 0;
4067         bool best_c_rdev_done;
4068
4069         c_rdevs = c_desc->coupled_rdevs;
4070         n_coupled = skip_coupled ? 1 : c_desc->n_coupled;
4071
4072         /*
4073          * Find the best possible voltage change on each loop. Leave the loop
4074          * if there isn't any possible change.
4075          */
4076         do {
4077                 best_c_rdev_done = false;
4078                 best_delta = 0;
4079                 best_min_uV = 0;
4080                 best_max_uV = 0;
4081                 best_c_rdev = 0;
4082                 best_rdev = NULL;
4083
4084                 /*
4085                  * Find highest difference between optimal voltage
4086                  * and current voltage.
4087                  */
4088                 for (i = 0; i < n_coupled; i++) {
4089                         /*
4090                          * optimal_uV is the best voltage that can be set for
4091                          * i-th regulator at the moment without violating
4092                          * max_spread constraint in order to balance
4093                          * the coupled voltages.
4094                          */
4095                         int optimal_uV = 0, optimal_max_uV = 0, current_uV = 0;
4096
4097                         if (test_bit(i, &c_rdev_done))
4098                                 continue;
4099
4100                         ret = regulator_get_optimal_voltage(c_rdevs[i],
4101                                                             &current_uV,
4102                                                             &optimal_uV,
4103                                                             &optimal_max_uV,
4104                                                             state, n_coupled);
4105                         if (ret < 0)
4106                                 goto out;
4107
4108                         delta = abs(optimal_uV - current_uV);
4109
4110                         if (delta && best_delta <= delta) {
4111                                 best_c_rdev_done = ret;
4112                                 best_delta = delta;
4113                                 best_rdev = c_rdevs[i];
4114                                 best_min_uV = optimal_uV;
4115                                 best_max_uV = optimal_max_uV;
4116                                 best_c_rdev = i;
4117                         }
4118                 }
4119
4120                 /* Nothing to change, return successfully */
4121                 if (!best_rdev) {
4122                         ret = 0;
4123                         goto out;
4124                 }
4125
4126                 ret = regulator_set_voltage_rdev(best_rdev, best_min_uV,
4127                                                  best_max_uV, state);
4128
4129                 if (ret < 0)
4130                         goto out;
4131
4132                 if (best_c_rdev_done)
4133                         set_bit(best_c_rdev, &c_rdev_done);
4134
4135         } while (n_coupled > 1);
4136
4137 out:
4138         return ret;
4139 }
4140
4141 static int regulator_balance_voltage(struct regulator_dev *rdev,
4142                                      suspend_state_t state)
4143 {
4144         struct coupling_desc *c_desc = &rdev->coupling_desc;
4145         struct regulator_coupler *coupler = c_desc->coupler;
4146         bool skip_coupled = false;
4147
4148         /*
4149          * If system is in a state other than PM_SUSPEND_ON, don't check
4150          * other coupled regulators.
4151          */
4152         if (state != PM_SUSPEND_ON)
4153                 skip_coupled = true;
4154
4155         if (c_desc->n_resolved < c_desc->n_coupled) {
4156                 rdev_err(rdev, "Not all coupled regulators registered\n");
4157                 return -EPERM;
4158         }
4159
4160         /* Invoke custom balancer for customized couplers */
4161         if (coupler && coupler->balance_voltage)
4162                 return coupler->balance_voltage(coupler, rdev, state);
4163
4164         return regulator_do_balance_voltage(rdev, state, skip_coupled);
4165 }
4166
4167 /**
4168  * regulator_set_voltage - set regulator output voltage
4169  * @regulator: regulator source
4170  * @min_uV: Minimum required voltage in uV
4171  * @max_uV: Maximum acceptable voltage in uV
4172  *
4173  * Sets a voltage regulator to the desired output voltage. This can be set
4174  * during any regulator state. IOW, regulator can be disabled or enabled.
4175  *
4176  * If the regulator is enabled then the voltage will change to the new value
4177  * immediately otherwise if the regulator is disabled the regulator will
4178  * output at the new voltage when enabled.
4179  *
4180  * NOTE: If the regulator is shared between several devices then the lowest
4181  * request voltage that meets the system constraints will be used.
4182  * Regulator system constraints must be set for this regulator before
4183  * calling this function otherwise this call will fail.
4184  */
4185 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
4186 {
4187         struct ww_acquire_ctx ww_ctx;
4188         int ret;
4189
4190         regulator_lock_dependent(regulator->rdev, &ww_ctx);
4191
4192         ret = regulator_set_voltage_unlocked(regulator, min_uV, max_uV,
4193                                              PM_SUSPEND_ON);
4194
4195         regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4196
4197         return ret;
4198 }
4199 EXPORT_SYMBOL_GPL(regulator_set_voltage);
4200
4201 static inline int regulator_suspend_toggle(struct regulator_dev *rdev,
4202                                            suspend_state_t state, bool en)
4203 {
4204         struct regulator_state *rstate;
4205
4206         rstate = regulator_get_suspend_state(rdev, state);
4207         if (rstate == NULL)
4208                 return -EINVAL;
4209
4210         if (!rstate->changeable)
4211                 return -EPERM;
4212
4213         rstate->enabled = (en) ? ENABLE_IN_SUSPEND : DISABLE_IN_SUSPEND;
4214
4215         return 0;
4216 }
4217
4218 int regulator_suspend_enable(struct regulator_dev *rdev,
4219                                     suspend_state_t state)
4220 {
4221         return regulator_suspend_toggle(rdev, state, true);
4222 }
4223 EXPORT_SYMBOL_GPL(regulator_suspend_enable);
4224
4225 int regulator_suspend_disable(struct regulator_dev *rdev,
4226                                      suspend_state_t state)
4227 {
4228         struct regulator *regulator;
4229         struct regulator_voltage *voltage;
4230
4231         /*
4232          * if any consumer wants this regulator device keeping on in
4233          * suspend states, don't set it as disabled.
4234          */
4235         list_for_each_entry(regulator, &rdev->consumer_list, list) {
4236                 voltage = &regulator->voltage[state];
4237                 if (voltage->min_uV || voltage->max_uV)
4238                         return 0;
4239         }
4240
4241         return regulator_suspend_toggle(rdev, state, false);
4242 }
4243 EXPORT_SYMBOL_GPL(regulator_suspend_disable);
4244
4245 static int _regulator_set_suspend_voltage(struct regulator *regulator,
4246                                           int min_uV, int max_uV,
4247                                           suspend_state_t state)
4248 {
4249         struct regulator_dev *rdev = regulator->rdev;
4250         struct regulator_state *rstate;
4251
4252         rstate = regulator_get_suspend_state(rdev, state);
4253         if (rstate == NULL)
4254                 return -EINVAL;
4255
4256         if (rstate->min_uV == rstate->max_uV) {
4257                 rdev_err(rdev, "The suspend voltage can't be changed!\n");
4258                 return -EPERM;
4259         }
4260
4261         return regulator_set_voltage_unlocked(regulator, min_uV, max_uV, state);
4262 }
4263
4264 int regulator_set_suspend_voltage(struct regulator *regulator, int min_uV,
4265                                   int max_uV, suspend_state_t state)
4266 {
4267         struct ww_acquire_ctx ww_ctx;
4268         int ret;
4269
4270         /* PM_SUSPEND_ON is handled by regulator_set_voltage() */
4271         if (regulator_check_states(state) || state == PM_SUSPEND_ON)
4272                 return -EINVAL;
4273
4274         regulator_lock_dependent(regulator->rdev, &ww_ctx);
4275
4276         ret = _regulator_set_suspend_voltage(regulator, min_uV,
4277                                              max_uV, state);
4278
4279         regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4280
4281         return ret;
4282 }
4283 EXPORT_SYMBOL_GPL(regulator_set_suspend_voltage);
4284
4285 /**
4286  * regulator_set_voltage_time - get raise/fall time
4287  * @regulator: regulator source
4288  * @old_uV: starting voltage in microvolts
4289  * @new_uV: target voltage in microvolts
4290  *
4291  * Provided with the starting and ending voltage, this function attempts to
4292  * calculate the time in microseconds required to rise or fall to this new
4293  * voltage.
4294  */
4295 int regulator_set_voltage_time(struct regulator *regulator,
4296                                int old_uV, int new_uV)
4297 {
4298         struct regulator_dev *rdev = regulator->rdev;
4299         const struct regulator_ops *ops = rdev->desc->ops;
4300         int old_sel = -1;
4301         int new_sel = -1;
4302         int voltage;
4303         int i;
4304
4305         if (ops->set_voltage_time)
4306                 return ops->set_voltage_time(rdev, old_uV, new_uV);
4307         else if (!ops->set_voltage_time_sel)
4308                 return _regulator_set_voltage_time(rdev, old_uV, new_uV);
4309
4310         /* Currently requires operations to do this */
4311         if (!ops->list_voltage || !rdev->desc->n_voltages)
4312                 return -EINVAL;
4313
4314         for (i = 0; i < rdev->desc->n_voltages; i++) {
4315                 /* We only look for exact voltage matches here */
4316                 if (i < rdev->desc->linear_min_sel)
4317                         continue;
4318
4319                 if (old_sel >= 0 && new_sel >= 0)
4320                         break;
4321
4322                 voltage = regulator_list_voltage(regulator, i);
4323                 if (voltage < 0)
4324                         return -EINVAL;
4325                 if (voltage == 0)
4326                         continue;
4327                 if (voltage == old_uV)
4328                         old_sel = i;
4329                 if (voltage == new_uV)
4330                         new_sel = i;
4331         }
4332
4333         if (old_sel < 0 || new_sel < 0)
4334                 return -EINVAL;
4335
4336         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
4337 }
4338 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
4339
4340 /**
4341  * regulator_set_voltage_time_sel - get raise/fall time
4342  * @rdev: regulator source device
4343  * @old_selector: selector for starting voltage
4344  * @new_selector: selector for target voltage
4345  *
4346  * Provided with the starting and target voltage selectors, this function
4347  * returns time in microseconds required to rise or fall to this new voltage
4348  *
4349  * Drivers providing ramp_delay in regulation_constraints can use this as their
4350  * set_voltage_time_sel() operation.
4351  */
4352 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
4353                                    unsigned int old_selector,
4354                                    unsigned int new_selector)
4355 {
4356         int old_volt, new_volt;
4357
4358         /* sanity check */
4359         if (!rdev->desc->ops->list_voltage)
4360                 return -EINVAL;
4361
4362         old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
4363         new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
4364
4365         if (rdev->desc->ops->set_voltage_time)
4366                 return rdev->desc->ops->set_voltage_time(rdev, old_volt,
4367                                                          new_volt);
4368         else
4369                 return _regulator_set_voltage_time(rdev, old_volt, new_volt);
4370 }
4371 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
4372
4373 int regulator_sync_voltage_rdev(struct regulator_dev *rdev)
4374 {
4375         int ret;
4376
4377         regulator_lock(rdev);
4378
4379         if (!rdev->desc->ops->set_voltage &&
4380             !rdev->desc->ops->set_voltage_sel) {
4381                 ret = -EINVAL;
4382                 goto out;
4383         }
4384
4385         /* balance only, if regulator is coupled */
4386         if (rdev->coupling_desc.n_coupled > 1)
4387                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4388         else
4389                 ret = -EOPNOTSUPP;
4390
4391 out:
4392         regulator_unlock(rdev);
4393         return ret;
4394 }
4395
4396 /**
4397  * regulator_sync_voltage - re-apply last regulator output voltage
4398  * @regulator: regulator source
4399  *
4400  * Re-apply the last configured voltage.  This is intended to be used
4401  * where some external control source the consumer is cooperating with
4402  * has caused the configured voltage to change.
4403  */
4404 int regulator_sync_voltage(struct regulator *regulator)
4405 {
4406         struct regulator_dev *rdev = regulator->rdev;
4407         struct regulator_voltage *voltage = &regulator->voltage[PM_SUSPEND_ON];
4408         int ret, min_uV, max_uV;
4409
4410         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
4411                 return 0;
4412
4413         regulator_lock(rdev);
4414
4415         if (!rdev->desc->ops->set_voltage &&
4416             !rdev->desc->ops->set_voltage_sel) {
4417                 ret = -EINVAL;
4418                 goto out;
4419         }
4420
4421         /* This is only going to work if we've had a voltage configured. */
4422         if (!voltage->min_uV && !voltage->max_uV) {
4423                 ret = -EINVAL;
4424                 goto out;
4425         }
4426
4427         min_uV = voltage->min_uV;
4428         max_uV = voltage->max_uV;
4429
4430         /* This should be a paranoia check... */
4431         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
4432         if (ret < 0)
4433                 goto out;
4434
4435         ret = regulator_check_consumers(rdev, &min_uV, &max_uV, 0);
4436         if (ret < 0)
4437                 goto out;
4438
4439         /* balance only, if regulator is coupled */
4440         if (rdev->coupling_desc.n_coupled > 1)
4441                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4442         else
4443                 ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
4444
4445 out:
4446         regulator_unlock(rdev);
4447         return ret;
4448 }
4449 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
4450
4451 int regulator_get_voltage_rdev(struct regulator_dev *rdev)
4452 {
4453         int sel, ret;
4454         bool bypassed;
4455
4456         if (rdev->desc->ops->get_bypass) {
4457                 ret = rdev->desc->ops->get_bypass(rdev, &bypassed);
4458                 if (ret < 0)
4459                         return ret;
4460                 if (bypassed) {
4461                         /* if bypassed the regulator must have a supply */
4462                         if (!rdev->supply) {
4463                                 rdev_err(rdev,
4464                                          "bypassed regulator has no supply!\n");
4465                                 return -EPROBE_DEFER;
4466                         }
4467
4468                         return regulator_get_voltage_rdev(rdev->supply->rdev);
4469                 }
4470         }
4471
4472         if (rdev->desc->ops->get_voltage_sel) {
4473                 sel = rdev->desc->ops->get_voltage_sel(rdev);
4474                 if (sel < 0)
4475                         return sel;
4476                 ret = rdev->desc->ops->list_voltage(rdev, sel);
4477         } else if (rdev->desc->ops->get_voltage) {
4478                 ret = rdev->desc->ops->get_voltage(rdev);
4479         } else if (rdev->desc->ops->list_voltage) {
4480                 ret = rdev->desc->ops->list_voltage(rdev, 0);
4481         } else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
4482                 ret = rdev->desc->fixed_uV;
4483         } else if (rdev->supply) {
4484                 ret = regulator_get_voltage_rdev(rdev->supply->rdev);
4485         } else if (rdev->supply_name) {
4486                 return -EPROBE_DEFER;
4487         } else {
4488                 return -EINVAL;
4489         }
4490
4491         if (ret < 0)
4492                 return ret;
4493         return ret - rdev->constraints->uV_offset;
4494 }
4495 EXPORT_SYMBOL_GPL(regulator_get_voltage_rdev);
4496
4497 /**
4498  * regulator_get_voltage - get regulator output voltage
4499  * @regulator: regulator source
4500  *
4501  * This returns the current regulator voltage in uV.
4502  *
4503  * NOTE: If the regulator is disabled it will return the voltage value. This
4504  * function should not be used to determine regulator state.
4505  */
4506 int regulator_get_voltage(struct regulator *regulator)
4507 {
4508         struct ww_acquire_ctx ww_ctx;
4509         int ret;
4510
4511         regulator_lock_dependent(regulator->rdev, &ww_ctx);
4512         ret = regulator_get_voltage_rdev(regulator->rdev);
4513         regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4514
4515         return ret;
4516 }
4517 EXPORT_SYMBOL_GPL(regulator_get_voltage);
4518
4519 /**
4520  * regulator_set_current_limit - set regulator output current limit
4521  * @regulator: regulator source
4522  * @min_uA: Minimum supported current in uA
4523  * @max_uA: Maximum supported current in uA
4524  *
4525  * Sets current sink to the desired output current. This can be set during
4526  * any regulator state. IOW, regulator can be disabled or enabled.
4527  *
4528  * If the regulator is enabled then the current will change to the new value
4529  * immediately otherwise if the regulator is disabled the regulator will
4530  * output at the new current when enabled.
4531  *
4532  * NOTE: Regulator system constraints must be set for this regulator before
4533  * calling this function otherwise this call will fail.
4534  */
4535 int regulator_set_current_limit(struct regulator *regulator,
4536                                int min_uA, int max_uA)
4537 {
4538         struct regulator_dev *rdev = regulator->rdev;
4539         int ret;
4540
4541         regulator_lock(rdev);
4542
4543         /* sanity check */
4544         if (!rdev->desc->ops->set_current_limit) {
4545                 ret = -EINVAL;
4546                 goto out;
4547         }
4548
4549         /* constraints check */
4550         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
4551         if (ret < 0)
4552                 goto out;
4553
4554         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
4555 out:
4556         regulator_unlock(rdev);
4557         return ret;
4558 }
4559 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
4560
4561 static int _regulator_get_current_limit_unlocked(struct regulator_dev *rdev)
4562 {
4563         /* sanity check */
4564         if (!rdev->desc->ops->get_current_limit)
4565                 return -EINVAL;
4566
4567         return rdev->desc->ops->get_current_limit(rdev);
4568 }
4569
4570 static int _regulator_get_current_limit(struct regulator_dev *rdev)
4571 {
4572         int ret;
4573
4574         regulator_lock(rdev);
4575         ret = _regulator_get_current_limit_unlocked(rdev);
4576         regulator_unlock(rdev);
4577
4578         return ret;
4579 }
4580
4581 /**
4582  * regulator_get_current_limit - get regulator output current
4583  * @regulator: regulator source
4584  *
4585  * This returns the current supplied by the specified current sink in uA.
4586  *
4587  * NOTE: If the regulator is disabled it will return the current value. This
4588  * function should not be used to determine regulator state.
4589  */
4590 int regulator_get_current_limit(struct regulator *regulator)
4591 {
4592         return _regulator_get_current_limit(regulator->rdev);
4593 }
4594 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
4595
4596 /**
4597  * regulator_set_mode - set regulator operating mode
4598  * @regulator: regulator source
4599  * @mode: operating mode - one of the REGULATOR_MODE constants
4600  *
4601  * Set regulator operating mode to increase regulator efficiency or improve
4602  * regulation performance.
4603  *
4604  * NOTE: Regulator system constraints must be set for this regulator before
4605  * calling this function otherwise this call will fail.
4606  */
4607 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
4608 {
4609         struct regulator_dev *rdev = regulator->rdev;
4610         int ret;
4611         int regulator_curr_mode;
4612
4613         regulator_lock(rdev);
4614
4615         /* sanity check */
4616         if (!rdev->desc->ops->set_mode) {
4617                 ret = -EINVAL;
4618                 goto out;
4619         }
4620
4621         /* return if the same mode is requested */
4622         if (rdev->desc->ops->get_mode) {
4623                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
4624                 if (regulator_curr_mode == mode) {
4625                         ret = 0;
4626                         goto out;
4627                 }
4628         }
4629
4630         /* constraints check */
4631         ret = regulator_mode_constrain(rdev, &mode);
4632         if (ret < 0)
4633                 goto out;
4634
4635         ret = rdev->desc->ops->set_mode(rdev, mode);
4636 out:
4637         regulator_unlock(rdev);
4638         return ret;
4639 }
4640 EXPORT_SYMBOL_GPL(regulator_set_mode);
4641
4642 static unsigned int _regulator_get_mode_unlocked(struct regulator_dev *rdev)
4643 {
4644         /* sanity check */
4645         if (!rdev->desc->ops->get_mode)
4646                 return -EINVAL;
4647
4648         return rdev->desc->ops->get_mode(rdev);
4649 }
4650
4651 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
4652 {
4653         int ret;
4654
4655         regulator_lock(rdev);
4656         ret = _regulator_get_mode_unlocked(rdev);
4657         regulator_unlock(rdev);
4658
4659         return ret;
4660 }
4661
4662 /**
4663  * regulator_get_mode - get regulator operating mode
4664  * @regulator: regulator source
4665  *
4666  * Get the current regulator operating mode.
4667  */
4668 unsigned int regulator_get_mode(struct regulator *regulator)
4669 {
4670         return _regulator_get_mode(regulator->rdev);
4671 }
4672 EXPORT_SYMBOL_GPL(regulator_get_mode);
4673
4674 static int rdev_get_cached_err_flags(struct regulator_dev *rdev)
4675 {
4676         int ret = 0;
4677
4678         if (rdev->use_cached_err) {
4679                 spin_lock(&rdev->err_lock);
4680                 ret = rdev->cached_err;
4681                 spin_unlock(&rdev->err_lock);
4682         }
4683         return ret;
4684 }
4685
4686 static int _regulator_get_error_flags(struct regulator_dev *rdev,
4687                                         unsigned int *flags)
4688 {
4689         int cached_flags, ret = 0;
4690
4691         regulator_lock(rdev);
4692
4693         cached_flags = rdev_get_cached_err_flags(rdev);
4694
4695         if (rdev->desc->ops->get_error_flags)
4696                 ret = rdev->desc->ops->get_error_flags(rdev, flags);
4697         else if (!rdev->use_cached_err)
4698                 ret = -EINVAL;
4699
4700         *flags |= cached_flags;
4701
4702         regulator_unlock(rdev);
4703
4704         return ret;
4705 }
4706
4707 /**
4708  * regulator_get_error_flags - get regulator error information
4709  * @regulator: regulator source
4710  * @flags: pointer to store error flags
4711  *
4712  * Get the current regulator error information.
4713  */
4714 int regulator_get_error_flags(struct regulator *regulator,
4715                                 unsigned int *flags)
4716 {
4717         return _regulator_get_error_flags(regulator->rdev, flags);
4718 }
4719 EXPORT_SYMBOL_GPL(regulator_get_error_flags);
4720
4721 /**
4722  * regulator_set_load - set regulator load
4723  * @regulator: regulator source
4724  * @uA_load: load current
4725  *
4726  * Notifies the regulator core of a new device load. This is then used by
4727  * DRMS (if enabled by constraints) to set the most efficient regulator
4728  * operating mode for the new regulator loading.
4729  *
4730  * Consumer devices notify their supply regulator of the maximum power
4731  * they will require (can be taken from device datasheet in the power
4732  * consumption tables) when they change operational status and hence power
4733  * state. Examples of operational state changes that can affect power
4734  * consumption are :-
4735  *
4736  *    o Device is opened / closed.
4737  *    o Device I/O is about to begin or has just finished.
4738  *    o Device is idling in between work.
4739  *
4740  * This information is also exported via sysfs to userspace.
4741  *
4742  * DRMS will sum the total requested load on the regulator and change
4743  * to the most efficient operating mode if platform constraints allow.
4744  *
4745  * NOTE: when a regulator consumer requests to have a regulator
4746  * disabled then any load that consumer requested no longer counts
4747  * toward the total requested load.  If the regulator is re-enabled
4748  * then the previously requested load will start counting again.
4749  *
4750  * If a regulator is an always-on regulator then an individual consumer's
4751  * load will still be removed if that consumer is fully disabled.
4752  *
4753  * On error a negative errno is returned.
4754  */
4755 int regulator_set_load(struct regulator *regulator, int uA_load)
4756 {
4757         struct regulator_dev *rdev = regulator->rdev;
4758         int old_uA_load;
4759         int ret = 0;
4760
4761         regulator_lock(rdev);
4762         old_uA_load = regulator->uA_load;
4763         regulator->uA_load = uA_load;
4764         if (regulator->enable_count && old_uA_load != uA_load) {
4765                 ret = drms_uA_update(rdev);
4766                 if (ret < 0)
4767                         regulator->uA_load = old_uA_load;
4768         }
4769         regulator_unlock(rdev);
4770
4771         return ret;
4772 }
4773 EXPORT_SYMBOL_GPL(regulator_set_load);
4774
4775 /**
4776  * regulator_allow_bypass - allow the regulator to go into bypass mode
4777  *
4778  * @regulator: Regulator to configure
4779  * @enable: enable or disable bypass mode
4780  *
4781  * Allow the regulator to go into bypass mode if all other consumers
4782  * for the regulator also enable bypass mode and the machine
4783  * constraints allow this.  Bypass mode means that the regulator is
4784  * simply passing the input directly to the output with no regulation.
4785  */
4786 int regulator_allow_bypass(struct regulator *regulator, bool enable)
4787 {
4788         struct regulator_dev *rdev = regulator->rdev;
4789         const char *name = rdev_get_name(rdev);
4790         int ret = 0;
4791
4792         if (!rdev->desc->ops->set_bypass)
4793                 return 0;
4794
4795         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_BYPASS))
4796                 return 0;
4797
4798         regulator_lock(rdev);
4799
4800         if (enable && !regulator->bypass) {
4801                 rdev->bypass_count++;
4802
4803                 if (rdev->bypass_count == rdev->open_count) {
4804                         trace_regulator_bypass_enable(name);
4805
4806                         ret = rdev->desc->ops->set_bypass(rdev, enable);
4807                         if (ret != 0)
4808                                 rdev->bypass_count--;
4809                         else
4810                                 trace_regulator_bypass_enable_complete(name);
4811                 }
4812
4813         } else if (!enable && regulator->bypass) {
4814                 rdev->bypass_count--;
4815
4816                 if (rdev->bypass_count != rdev->open_count) {
4817                         trace_regulator_bypass_disable(name);
4818
4819                         ret = rdev->desc->ops->set_bypass(rdev, enable);
4820                         if (ret != 0)
4821                                 rdev->bypass_count++;
4822                         else
4823                                 trace_regulator_bypass_disable_complete(name);
4824                 }
4825         }
4826
4827         if (ret == 0)
4828                 regulator->bypass = enable;
4829
4830         regulator_unlock(rdev);
4831
4832         return ret;
4833 }
4834 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
4835
4836 /**
4837  * regulator_register_notifier - register regulator event notifier
4838  * @regulator: regulator source
4839  * @nb: notifier block
4840  *
4841  * Register notifier block to receive regulator events.
4842  */
4843 int regulator_register_notifier(struct regulator *regulator,
4844                               struct notifier_block *nb)
4845 {
4846         return blocking_notifier_chain_register(&regulator->rdev->notifier,
4847                                                 nb);
4848 }
4849 EXPORT_SYMBOL_GPL(regulator_register_notifier);
4850
4851 /**
4852  * regulator_unregister_notifier - unregister regulator event notifier
4853  * @regulator: regulator source
4854  * @nb: notifier block
4855  *
4856  * Unregister regulator event notifier block.
4857  */
4858 int regulator_unregister_notifier(struct regulator *regulator,
4859                                 struct notifier_block *nb)
4860 {
4861         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
4862                                                   nb);
4863 }
4864 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
4865
4866 /* notify regulator consumers and downstream regulator consumers.
4867  * Note mutex must be held by caller.
4868  */
4869 static int _notifier_call_chain(struct regulator_dev *rdev,
4870                                   unsigned long event, void *data)
4871 {
4872         /* call rdev chain first */
4873         int ret =  blocking_notifier_call_chain(&rdev->notifier, event, data);
4874
4875         if (IS_REACHABLE(CONFIG_REGULATOR_NETLINK_EVENTS)) {
4876                 struct device *parent = rdev->dev.parent;
4877                 const char *rname = rdev_get_name(rdev);
4878                 char name[32];
4879
4880                 /* Avoid duplicate debugfs directory names */
4881                 if (parent && rname == rdev->desc->name) {
4882                         snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
4883                                  rname);
4884                         rname = name;
4885                 }
4886                 reg_generate_netlink_event(rname, event);
4887         }
4888
4889         return ret;
4890 }
4891
4892 int _regulator_bulk_get(struct device *dev, int num_consumers,
4893                         struct regulator_bulk_data *consumers, enum regulator_get_type get_type)
4894 {
4895         int i;
4896         int ret;
4897
4898         for (i = 0; i < num_consumers; i++)
4899                 consumers[i].consumer = NULL;
4900
4901         for (i = 0; i < num_consumers; i++) {
4902                 consumers[i].consumer = _regulator_get(dev,
4903                                                        consumers[i].supply, get_type);
4904                 if (IS_ERR(consumers[i].consumer)) {
4905                         ret = dev_err_probe(dev, PTR_ERR(consumers[i].consumer),
4906                                             "Failed to get supply '%s'",
4907                                             consumers[i].supply);
4908                         consumers[i].consumer = NULL;
4909                         goto err;
4910                 }
4911
4912                 if (consumers[i].init_load_uA > 0) {
4913                         ret = regulator_set_load(consumers[i].consumer,
4914                                                  consumers[i].init_load_uA);
4915                         if (ret) {
4916                                 i++;
4917                                 goto err;
4918                         }
4919                 }
4920         }
4921
4922         return 0;
4923
4924 err:
4925         while (--i >= 0)
4926                 regulator_put(consumers[i].consumer);
4927
4928         return ret;
4929 }
4930
4931 /**
4932  * regulator_bulk_get - get multiple regulator consumers
4933  *
4934  * @dev:           Device to supply
4935  * @num_consumers: Number of consumers to register
4936  * @consumers:     Configuration of consumers; clients are stored here.
4937  *
4938  * @return 0 on success, an errno on failure.
4939  *
4940  * This helper function allows drivers to get several regulator
4941  * consumers in one operation.  If any of the regulators cannot be
4942  * acquired then any regulators that were allocated will be freed
4943  * before returning to the caller.
4944  */
4945 int regulator_bulk_get(struct device *dev, int num_consumers,
4946                        struct regulator_bulk_data *consumers)
4947 {
4948         return _regulator_bulk_get(dev, num_consumers, consumers, NORMAL_GET);
4949 }
4950 EXPORT_SYMBOL_GPL(regulator_bulk_get);
4951
4952 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
4953 {
4954         struct regulator_bulk_data *bulk = data;
4955
4956         bulk->ret = regulator_enable(bulk->consumer);
4957 }
4958
4959 /**
4960  * regulator_bulk_enable - enable multiple regulator consumers
4961  *
4962  * @num_consumers: Number of consumers
4963  * @consumers:     Consumer data; clients are stored here.
4964  * @return         0 on success, an errno on failure
4965  *
4966  * This convenience API allows consumers to enable multiple regulator
4967  * clients in a single API call.  If any consumers cannot be enabled
4968  * then any others that were enabled will be disabled again prior to
4969  * return.
4970  */
4971 int regulator_bulk_enable(int num_consumers,
4972                           struct regulator_bulk_data *consumers)
4973 {
4974         ASYNC_DOMAIN_EXCLUSIVE(async_domain);
4975         int i;
4976         int ret = 0;
4977
4978         for (i = 0; i < num_consumers; i++) {
4979                 async_schedule_domain(regulator_bulk_enable_async,
4980                                       &consumers[i], &async_domain);
4981         }
4982
4983         async_synchronize_full_domain(&async_domain);
4984
4985         /* If any consumer failed we need to unwind any that succeeded */
4986         for (i = 0; i < num_consumers; i++) {
4987                 if (consumers[i].ret != 0) {
4988                         ret = consumers[i].ret;
4989                         goto err;
4990                 }
4991         }
4992
4993         return 0;
4994
4995 err:
4996         for (i = 0; i < num_consumers; i++) {
4997                 if (consumers[i].ret < 0)
4998                         pr_err("Failed to enable %s: %pe\n", consumers[i].supply,
4999                                ERR_PTR(consumers[i].ret));
5000                 else
5001                         regulator_disable(consumers[i].consumer);
5002         }
5003
5004         return ret;
5005 }
5006 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
5007
5008 /**
5009  * regulator_bulk_disable - disable multiple regulator consumers
5010  *
5011  * @num_consumers: Number of consumers
5012  * @consumers:     Consumer data; clients are stored here.
5013  * @return         0 on success, an errno on failure
5014  *
5015  * This convenience API allows consumers to disable multiple regulator
5016  * clients in a single API call.  If any consumers cannot be disabled
5017  * then any others that were disabled will be enabled again prior to
5018  * return.
5019  */
5020 int regulator_bulk_disable(int num_consumers,
5021                            struct regulator_bulk_data *consumers)
5022 {
5023         int i;
5024         int ret, r;
5025
5026         for (i = num_consumers - 1; i >= 0; --i) {
5027                 ret = regulator_disable(consumers[i].consumer);
5028                 if (ret != 0)
5029                         goto err;
5030         }
5031
5032         return 0;
5033
5034 err:
5035         pr_err("Failed to disable %s: %pe\n", consumers[i].supply, ERR_PTR(ret));
5036         for (++i; i < num_consumers; ++i) {
5037                 r = regulator_enable(consumers[i].consumer);
5038                 if (r != 0)
5039                         pr_err("Failed to re-enable %s: %pe\n",
5040                                consumers[i].supply, ERR_PTR(r));
5041         }
5042
5043         return ret;
5044 }
5045 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
5046
5047 /**
5048  * regulator_bulk_force_disable - force disable multiple regulator consumers
5049  *
5050  * @num_consumers: Number of consumers
5051  * @consumers:     Consumer data; clients are stored here.
5052  * @return         0 on success, an errno on failure
5053  *
5054  * This convenience API allows consumers to forcibly disable multiple regulator
5055  * clients in a single API call.
5056  * NOTE: This should be used for situations when device damage will
5057  * likely occur if the regulators are not disabled (e.g. over temp).
5058  * Although regulator_force_disable function call for some consumers can
5059  * return error numbers, the function is called for all consumers.
5060  */
5061 int regulator_bulk_force_disable(int num_consumers,
5062                            struct regulator_bulk_data *consumers)
5063 {
5064         int i;
5065         int ret = 0;
5066
5067         for (i = 0; i < num_consumers; i++) {
5068                 consumers[i].ret =
5069                             regulator_force_disable(consumers[i].consumer);
5070
5071                 /* Store first error for reporting */
5072                 if (consumers[i].ret && !ret)
5073                         ret = consumers[i].ret;
5074         }
5075
5076         return ret;
5077 }
5078 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
5079
5080 /**
5081  * regulator_bulk_free - free multiple regulator consumers
5082  *
5083  * @num_consumers: Number of consumers
5084  * @consumers:     Consumer data; clients are stored here.
5085  *
5086  * This convenience API allows consumers to free multiple regulator
5087  * clients in a single API call.
5088  */
5089 void regulator_bulk_free(int num_consumers,
5090                          struct regulator_bulk_data *consumers)
5091 {
5092         int i;
5093
5094         for (i = 0; i < num_consumers; i++) {
5095                 regulator_put(consumers[i].consumer);
5096                 consumers[i].consumer = NULL;
5097         }
5098 }
5099 EXPORT_SYMBOL_GPL(regulator_bulk_free);
5100
5101 /**
5102  * regulator_handle_critical - Handle events for system-critical regulators.
5103  * @rdev: The regulator device.
5104  * @event: The event being handled.
5105  *
5106  * This function handles critical events such as under-voltage, over-current,
5107  * and unknown errors for regulators deemed system-critical. On detecting such
5108  * events, it triggers a hardware protection shutdown with a defined timeout.
5109  */
5110 static void regulator_handle_critical(struct regulator_dev *rdev,
5111                                       unsigned long event)
5112 {
5113         const char *reason = NULL;
5114
5115         if (!rdev->constraints->system_critical)
5116                 return;
5117
5118         switch (event) {
5119         case REGULATOR_EVENT_UNDER_VOLTAGE:
5120                 reason = "System critical regulator: voltage drop detected";
5121                 break;
5122         case REGULATOR_EVENT_OVER_CURRENT:
5123                 reason = "System critical regulator: over-current detected";
5124                 break;
5125         case REGULATOR_EVENT_FAIL:
5126                 reason = "System critical regulator: unknown error";
5127         }
5128
5129         if (!reason)
5130                 return;
5131
5132         hw_protection_shutdown(reason,
5133                                rdev->constraints->uv_less_critical_window_ms);
5134 }
5135
5136 /**
5137  * regulator_notifier_call_chain - call regulator event notifier
5138  * @rdev: regulator source
5139  * @event: notifier block
5140  * @data: callback-specific data.
5141  *
5142  * Called by regulator drivers to notify clients a regulator event has
5143  * occurred.
5144  */
5145 int regulator_notifier_call_chain(struct regulator_dev *rdev,
5146                                   unsigned long event, void *data)
5147 {
5148         regulator_handle_critical(rdev, event);
5149
5150         _notifier_call_chain(rdev, event, data);
5151         return NOTIFY_DONE;
5152
5153 }
5154 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
5155
5156 /**
5157  * regulator_mode_to_status - convert a regulator mode into a status
5158  *
5159  * @mode: Mode to convert
5160  *
5161  * Convert a regulator mode into a status.
5162  */
5163 int regulator_mode_to_status(unsigned int mode)
5164 {
5165         switch (mode) {
5166         case REGULATOR_MODE_FAST:
5167                 return REGULATOR_STATUS_FAST;
5168         case REGULATOR_MODE_NORMAL:
5169                 return REGULATOR_STATUS_NORMAL;
5170         case REGULATOR_MODE_IDLE:
5171                 return REGULATOR_STATUS_IDLE;
5172         case REGULATOR_MODE_STANDBY:
5173                 return REGULATOR_STATUS_STANDBY;
5174         default:
5175                 return REGULATOR_STATUS_UNDEFINED;
5176         }
5177 }
5178 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
5179
5180 static struct attribute *regulator_dev_attrs[] = {
5181         &dev_attr_name.attr,
5182         &dev_attr_num_users.attr,
5183         &dev_attr_type.attr,
5184         &dev_attr_microvolts.attr,
5185         &dev_attr_microamps.attr,
5186         &dev_attr_opmode.attr,
5187         &dev_attr_state.attr,
5188         &dev_attr_status.attr,
5189         &dev_attr_bypass.attr,
5190         &dev_attr_requested_microamps.attr,
5191         &dev_attr_min_microvolts.attr,
5192         &dev_attr_max_microvolts.attr,
5193         &dev_attr_min_microamps.attr,
5194         &dev_attr_max_microamps.attr,
5195         &dev_attr_under_voltage.attr,
5196         &dev_attr_over_current.attr,
5197         &dev_attr_regulation_out.attr,
5198         &dev_attr_fail.attr,
5199         &dev_attr_over_temp.attr,
5200         &dev_attr_under_voltage_warn.attr,
5201         &dev_attr_over_current_warn.attr,
5202         &dev_attr_over_voltage_warn.attr,
5203         &dev_attr_over_temp_warn.attr,
5204         &dev_attr_suspend_standby_state.attr,
5205         &dev_attr_suspend_mem_state.attr,
5206         &dev_attr_suspend_disk_state.attr,
5207         &dev_attr_suspend_standby_microvolts.attr,
5208         &dev_attr_suspend_mem_microvolts.attr,
5209         &dev_attr_suspend_disk_microvolts.attr,
5210         &dev_attr_suspend_standby_mode.attr,
5211         &dev_attr_suspend_mem_mode.attr,
5212         &dev_attr_suspend_disk_mode.attr,
5213         NULL
5214 };
5215
5216 /*
5217  * To avoid cluttering sysfs (and memory) with useless state, only
5218  * create attributes that can be meaningfully displayed.
5219  */
5220 static umode_t regulator_attr_is_visible(struct kobject *kobj,
5221                                          struct attribute *attr, int idx)
5222 {
5223         struct device *dev = kobj_to_dev(kobj);
5224         struct regulator_dev *rdev = dev_to_rdev(dev);
5225         const struct regulator_ops *ops = rdev->desc->ops;
5226         umode_t mode = attr->mode;
5227
5228         /* these three are always present */
5229         if (attr == &dev_attr_name.attr ||
5230             attr == &dev_attr_num_users.attr ||
5231             attr == &dev_attr_type.attr)
5232                 return mode;
5233
5234         /* some attributes need specific methods to be displayed */
5235         if (attr == &dev_attr_microvolts.attr) {
5236                 if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
5237                     (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
5238                     (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
5239                     (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
5240                         return mode;
5241                 return 0;
5242         }
5243
5244         if (attr == &dev_attr_microamps.attr)
5245                 return ops->get_current_limit ? mode : 0;
5246
5247         if (attr == &dev_attr_opmode.attr)
5248                 return ops->get_mode ? mode : 0;
5249
5250         if (attr == &dev_attr_state.attr)
5251                 return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
5252
5253         if (attr == &dev_attr_status.attr)
5254                 return ops->get_status ? mode : 0;
5255
5256         if (attr == &dev_attr_bypass.attr)
5257                 return ops->get_bypass ? mode : 0;
5258
5259         if (attr == &dev_attr_under_voltage.attr ||
5260             attr == &dev_attr_over_current.attr ||
5261             attr == &dev_attr_regulation_out.attr ||
5262             attr == &dev_attr_fail.attr ||
5263             attr == &dev_attr_over_temp.attr ||
5264             attr == &dev_attr_under_voltage_warn.attr ||
5265             attr == &dev_attr_over_current_warn.attr ||
5266             attr == &dev_attr_over_voltage_warn.attr ||
5267             attr == &dev_attr_over_temp_warn.attr)
5268                 return ops->get_error_flags ? mode : 0;
5269
5270         /* constraints need specific supporting methods */
5271         if (attr == &dev_attr_min_microvolts.attr ||
5272             attr == &dev_attr_max_microvolts.attr)
5273                 return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
5274
5275         if (attr == &dev_attr_min_microamps.attr ||
5276             attr == &dev_attr_max_microamps.attr)
5277                 return ops->set_current_limit ? mode : 0;
5278
5279         if (attr == &dev_attr_suspend_standby_state.attr ||
5280             attr == &dev_attr_suspend_mem_state.attr ||
5281             attr == &dev_attr_suspend_disk_state.attr)
5282                 return mode;
5283
5284         if (attr == &dev_attr_suspend_standby_microvolts.attr ||
5285             attr == &dev_attr_suspend_mem_microvolts.attr ||
5286             attr == &dev_attr_suspend_disk_microvolts.attr)
5287                 return ops->set_suspend_voltage ? mode : 0;
5288
5289         if (attr == &dev_attr_suspend_standby_mode.attr ||
5290             attr == &dev_attr_suspend_mem_mode.attr ||
5291             attr == &dev_attr_suspend_disk_mode.attr)
5292                 return ops->set_suspend_mode ? mode : 0;
5293
5294         return mode;
5295 }
5296
5297 static const struct attribute_group regulator_dev_group = {
5298         .attrs = regulator_dev_attrs,
5299         .is_visible = regulator_attr_is_visible,
5300 };
5301
5302 static const struct attribute_group *regulator_dev_groups[] = {
5303         &regulator_dev_group,
5304         NULL
5305 };
5306
5307 static void regulator_dev_release(struct device *dev)
5308 {
5309         struct regulator_dev *rdev = dev_get_drvdata(dev);
5310
5311         debugfs_remove_recursive(rdev->debugfs);
5312         kfree(rdev->constraints);
5313         of_node_put(rdev->dev.of_node);
5314         kfree(rdev);
5315 }
5316
5317 static void rdev_init_debugfs(struct regulator_dev *rdev)
5318 {
5319         struct device *parent = rdev->dev.parent;
5320         const char *rname = rdev_get_name(rdev);
5321         char name[NAME_MAX];
5322
5323         /* Avoid duplicate debugfs directory names */
5324         if (parent && rname == rdev->desc->name) {
5325                 snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
5326                          rname);
5327                 rname = name;
5328         }
5329
5330         rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
5331         if (IS_ERR(rdev->debugfs))
5332                 rdev_dbg(rdev, "Failed to create debugfs directory\n");
5333
5334         debugfs_create_u32("use_count", 0444, rdev->debugfs,
5335                            &rdev->use_count);
5336         debugfs_create_u32("open_count", 0444, rdev->debugfs,
5337                            &rdev->open_count);
5338         debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
5339                            &rdev->bypass_count);
5340 }
5341
5342 static int regulator_register_resolve_supply(struct device *dev, void *data)
5343 {
5344         struct regulator_dev *rdev = dev_to_rdev(dev);
5345
5346         if (regulator_resolve_supply(rdev))
5347                 rdev_dbg(rdev, "unable to resolve supply\n");
5348
5349         return 0;
5350 }
5351
5352 int regulator_coupler_register(struct regulator_coupler *coupler)
5353 {
5354         mutex_lock(&regulator_list_mutex);
5355         list_add_tail(&coupler->list, &regulator_coupler_list);
5356         mutex_unlock(&regulator_list_mutex);
5357
5358         return 0;
5359 }
5360
5361 static struct regulator_coupler *
5362 regulator_find_coupler(struct regulator_dev *rdev)
5363 {
5364         struct regulator_coupler *coupler;
5365         int err;
5366
5367         /*
5368          * Note that regulators are appended to the list and the generic
5369          * coupler is registered first, hence it will be attached at last
5370          * if nobody cared.
5371          */
5372         list_for_each_entry_reverse(coupler, &regulator_coupler_list, list) {
5373                 err = coupler->attach_regulator(coupler, rdev);
5374                 if (!err) {
5375                         if (!coupler->balance_voltage &&
5376                             rdev->coupling_desc.n_coupled > 2)
5377                                 goto err_unsupported;
5378
5379                         return coupler;
5380                 }
5381
5382                 if (err < 0)
5383                         return ERR_PTR(err);
5384
5385                 if (err == 1)
5386                         continue;
5387
5388                 break;
5389         }
5390
5391         return ERR_PTR(-EINVAL);
5392
5393 err_unsupported:
5394         if (coupler->detach_regulator)
5395                 coupler->detach_regulator(coupler, rdev);
5396
5397         rdev_err(rdev,
5398                 "Voltage balancing for multiple regulator couples is unimplemented\n");
5399
5400         return ERR_PTR(-EPERM);
5401 }
5402
5403 static void regulator_resolve_coupling(struct regulator_dev *rdev)
5404 {
5405         struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5406         struct coupling_desc *c_desc = &rdev->coupling_desc;
5407         int n_coupled = c_desc->n_coupled;
5408         struct regulator_dev *c_rdev;
5409         int i;
5410
5411         for (i = 1; i < n_coupled; i++) {
5412                 /* already resolved */
5413                 if (c_desc->coupled_rdevs[i])
5414                         continue;
5415
5416                 c_rdev = of_parse_coupled_regulator(rdev, i - 1);
5417
5418                 if (!c_rdev)
5419                         continue;
5420
5421                 if (c_rdev->coupling_desc.coupler != coupler) {
5422                         rdev_err(rdev, "coupler mismatch with %s\n",
5423                                  rdev_get_name(c_rdev));
5424                         return;
5425                 }
5426
5427                 c_desc->coupled_rdevs[i] = c_rdev;
5428                 c_desc->n_resolved++;
5429
5430                 regulator_resolve_coupling(c_rdev);
5431         }
5432 }
5433
5434 static void regulator_remove_coupling(struct regulator_dev *rdev)
5435 {
5436         struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5437         struct coupling_desc *__c_desc, *c_desc = &rdev->coupling_desc;
5438         struct regulator_dev *__c_rdev, *c_rdev;
5439         unsigned int __n_coupled, n_coupled;
5440         int i, k;
5441         int err;
5442
5443         n_coupled = c_desc->n_coupled;
5444
5445         for (i = 1; i < n_coupled; i++) {
5446                 c_rdev = c_desc->coupled_rdevs[i];
5447
5448                 if (!c_rdev)
5449                         continue;
5450
5451                 regulator_lock(c_rdev);
5452
5453                 __c_desc = &c_rdev->coupling_desc;
5454                 __n_coupled = __c_desc->n_coupled;
5455
5456                 for (k = 1; k < __n_coupled; k++) {
5457                         __c_rdev = __c_desc->coupled_rdevs[k];
5458
5459                         if (__c_rdev == rdev) {
5460                                 __c_desc->coupled_rdevs[k] = NULL;
5461                                 __c_desc->n_resolved--;
5462                                 break;
5463                         }
5464                 }
5465
5466                 regulator_unlock(c_rdev);
5467
5468                 c_desc->coupled_rdevs[i] = NULL;
5469                 c_desc->n_resolved--;
5470         }
5471
5472         if (coupler && coupler->detach_regulator) {
5473                 err = coupler->detach_regulator(coupler, rdev);
5474                 if (err)
5475                         rdev_err(rdev, "failed to detach from coupler: %pe\n",
5476                                  ERR_PTR(err));
5477         }
5478
5479         kfree(rdev->coupling_desc.coupled_rdevs);
5480         rdev->coupling_desc.coupled_rdevs = NULL;
5481 }
5482
5483 static int regulator_init_coupling(struct regulator_dev *rdev)
5484 {
5485         struct regulator_dev **coupled;
5486         int err, n_phandles;
5487
5488         if (!IS_ENABLED(CONFIG_OF))
5489                 n_phandles = 0;
5490         else
5491                 n_phandles = of_get_n_coupled(rdev);
5492
5493         coupled = kcalloc(n_phandles + 1, sizeof(*coupled), GFP_KERNEL);
5494         if (!coupled)
5495                 return -ENOMEM;
5496
5497         rdev->coupling_desc.coupled_rdevs = coupled;
5498
5499         /*
5500          * Every regulator should always have coupling descriptor filled with
5501          * at least pointer to itself.
5502          */
5503         rdev->coupling_desc.coupled_rdevs[0] = rdev;
5504         rdev->coupling_desc.n_coupled = n_phandles + 1;
5505         rdev->coupling_desc.n_resolved++;
5506
5507         /* regulator isn't coupled */
5508         if (n_phandles == 0)
5509                 return 0;
5510
5511         if (!of_check_coupling_data(rdev))
5512                 return -EPERM;
5513
5514         mutex_lock(&regulator_list_mutex);
5515         rdev->coupling_desc.coupler = regulator_find_coupler(rdev);
5516         mutex_unlock(&regulator_list_mutex);
5517
5518         if (IS_ERR(rdev->coupling_desc.coupler)) {
5519                 err = PTR_ERR(rdev->coupling_desc.coupler);
5520                 rdev_err(rdev, "failed to get coupler: %pe\n", ERR_PTR(err));
5521                 return err;
5522         }
5523
5524         return 0;
5525 }
5526
5527 static int generic_coupler_attach(struct regulator_coupler *coupler,
5528                                   struct regulator_dev *rdev)
5529 {
5530         if (rdev->coupling_desc.n_coupled > 2) {
5531                 rdev_err(rdev,
5532                          "Voltage balancing for multiple regulator couples is unimplemented\n");
5533                 return -EPERM;
5534         }
5535
5536         if (!rdev->constraints->always_on) {
5537                 rdev_err(rdev,
5538                          "Coupling of a non always-on regulator is unimplemented\n");
5539                 return -ENOTSUPP;
5540         }
5541
5542         return 0;
5543 }
5544
5545 static struct regulator_coupler generic_regulator_coupler = {
5546         .attach_regulator = generic_coupler_attach,
5547 };
5548
5549 /**
5550  * regulator_register - register regulator
5551  * @dev: the device that drive the regulator
5552  * @regulator_desc: regulator to register
5553  * @cfg: runtime configuration for regulator
5554  *
5555  * Called by regulator drivers to register a regulator.
5556  * Returns a valid pointer to struct regulator_dev on success
5557  * or an ERR_PTR() on error.
5558  */
5559 struct regulator_dev *
5560 regulator_register(struct device *dev,
5561                    const struct regulator_desc *regulator_desc,
5562                    const struct regulator_config *cfg)
5563 {
5564         const struct regulator_init_data *init_data;
5565         struct regulator_config *config = NULL;
5566         static atomic_t regulator_no = ATOMIC_INIT(-1);
5567         struct regulator_dev *rdev;
5568         bool dangling_cfg_gpiod = false;
5569         bool dangling_of_gpiod = false;
5570         int ret, i;
5571         bool resolved_early = false;
5572
5573         if (cfg == NULL)
5574                 return ERR_PTR(-EINVAL);
5575         if (cfg->ena_gpiod)
5576                 dangling_cfg_gpiod = true;
5577         if (regulator_desc == NULL) {
5578                 ret = -EINVAL;
5579                 goto rinse;
5580         }
5581
5582         WARN_ON(!dev || !cfg->dev);
5583
5584         if (regulator_desc->name == NULL || regulator_desc->ops == NULL) {
5585                 ret = -EINVAL;
5586                 goto rinse;
5587         }
5588
5589         if (regulator_desc->type != REGULATOR_VOLTAGE &&
5590             regulator_desc->type != REGULATOR_CURRENT) {
5591                 ret = -EINVAL;
5592                 goto rinse;
5593         }
5594
5595         /* Only one of each should be implemented */
5596         WARN_ON(regulator_desc->ops->get_voltage &&
5597                 regulator_desc->ops->get_voltage_sel);
5598         WARN_ON(regulator_desc->ops->set_voltage &&
5599                 regulator_desc->ops->set_voltage_sel);
5600
5601         /* If we're using selectors we must implement list_voltage. */
5602         if (regulator_desc->ops->get_voltage_sel &&
5603             !regulator_desc->ops->list_voltage) {
5604                 ret = -EINVAL;
5605                 goto rinse;
5606         }
5607         if (regulator_desc->ops->set_voltage_sel &&
5608             !regulator_desc->ops->list_voltage) {
5609                 ret = -EINVAL;
5610                 goto rinse;
5611         }
5612
5613         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
5614         if (rdev == NULL) {
5615                 ret = -ENOMEM;
5616                 goto rinse;
5617         }
5618         device_initialize(&rdev->dev);
5619         dev_set_drvdata(&rdev->dev, rdev);
5620         rdev->dev.class = &regulator_class;
5621         spin_lock_init(&rdev->err_lock);
5622
5623         /*
5624          * Duplicate the config so the driver could override it after
5625          * parsing init data.
5626          */
5627         config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
5628         if (config == NULL) {
5629                 ret = -ENOMEM;
5630                 goto clean;
5631         }
5632
5633         init_data = regulator_of_get_init_data(dev, regulator_desc, config,
5634                                                &rdev->dev.of_node);
5635
5636         /*
5637          * Sometimes not all resources are probed already so we need to take
5638          * that into account. This happens most the time if the ena_gpiod comes
5639          * from a gpio extender or something else.
5640          */
5641         if (PTR_ERR(init_data) == -EPROBE_DEFER) {
5642                 ret = -EPROBE_DEFER;
5643                 goto clean;
5644         }
5645
5646         /*
5647          * We need to keep track of any GPIO descriptor coming from the
5648          * device tree until we have handled it over to the core. If the
5649          * config that was passed in to this function DOES NOT contain
5650          * a descriptor, and the config after this call DOES contain
5651          * a descriptor, we definitely got one from parsing the device
5652          * tree.
5653          */
5654         if (!cfg->ena_gpiod && config->ena_gpiod)
5655                 dangling_of_gpiod = true;
5656         if (!init_data) {
5657                 init_data = config->init_data;
5658                 rdev->dev.of_node = of_node_get(config->of_node);
5659         }
5660
5661         ww_mutex_init(&rdev->mutex, &regulator_ww_class);
5662         rdev->reg_data = config->driver_data;
5663         rdev->owner = regulator_desc->owner;
5664         rdev->desc = regulator_desc;
5665         if (config->regmap)
5666                 rdev->regmap = config->regmap;
5667         else if (dev_get_regmap(dev, NULL))
5668                 rdev->regmap = dev_get_regmap(dev, NULL);
5669         else if (dev->parent)
5670                 rdev->regmap = dev_get_regmap(dev->parent, NULL);
5671         INIT_LIST_HEAD(&rdev->consumer_list);
5672         INIT_LIST_HEAD(&rdev->list);
5673         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
5674         INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
5675
5676         if (init_data && init_data->supply_regulator)
5677                 rdev->supply_name = init_data->supply_regulator;
5678         else if (regulator_desc->supply_name)
5679                 rdev->supply_name = regulator_desc->supply_name;
5680
5681         /* register with sysfs */
5682         rdev->dev.parent = config->dev;
5683         dev_set_name(&rdev->dev, "regulator.%lu",
5684                     (unsigned long) atomic_inc_return(&regulator_no));
5685
5686         /* set regulator constraints */
5687         if (init_data)
5688                 rdev->constraints = kmemdup(&init_data->constraints,
5689                                             sizeof(*rdev->constraints),
5690                                             GFP_KERNEL);
5691         else
5692                 rdev->constraints = kzalloc(sizeof(*rdev->constraints),
5693                                             GFP_KERNEL);
5694         if (!rdev->constraints) {
5695                 ret = -ENOMEM;
5696                 goto wash;
5697         }
5698
5699         if ((rdev->supply_name && !rdev->supply) &&
5700                 (rdev->constraints->always_on ||
5701                  rdev->constraints->boot_on)) {
5702                 ret = regulator_resolve_supply(rdev);
5703                 if (ret)
5704                         rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
5705                                          ERR_PTR(ret));
5706
5707                 resolved_early = true;
5708         }
5709
5710         /* perform any regulator specific init */
5711         if (init_data && init_data->regulator_init) {
5712                 ret = init_data->regulator_init(rdev->reg_data);
5713                 if (ret < 0)
5714                         goto wash;
5715         }
5716
5717         if (config->ena_gpiod) {
5718                 ret = regulator_ena_gpio_request(rdev, config);
5719                 if (ret != 0) {
5720                         rdev_err(rdev, "Failed to request enable GPIO: %pe\n",
5721                                  ERR_PTR(ret));
5722                         goto wash;
5723                 }
5724                 /* The regulator core took over the GPIO descriptor */
5725                 dangling_cfg_gpiod = false;
5726                 dangling_of_gpiod = false;
5727         }
5728
5729         ret = set_machine_constraints(rdev);
5730         if (ret == -EPROBE_DEFER && !resolved_early) {
5731                 /* Regulator might be in bypass mode and so needs its supply
5732                  * to set the constraints
5733                  */
5734                 /* FIXME: this currently triggers a chicken-and-egg problem
5735                  * when creating -SUPPLY symlink in sysfs to a regulator
5736                  * that is just being created
5737                  */
5738                 rdev_dbg(rdev, "will resolve supply early: %s\n",
5739                          rdev->supply_name);
5740                 ret = regulator_resolve_supply(rdev);
5741                 if (!ret)
5742                         ret = set_machine_constraints(rdev);
5743                 else
5744                         rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
5745                                  ERR_PTR(ret));
5746         }
5747         if (ret < 0)
5748                 goto wash;
5749
5750         ret = regulator_init_coupling(rdev);
5751         if (ret < 0)
5752                 goto wash;
5753
5754         /* add consumers devices */
5755         if (init_data) {
5756                 for (i = 0; i < init_data->num_consumer_supplies; i++) {
5757                         ret = set_consumer_device_supply(rdev,
5758                                 init_data->consumer_supplies[i].dev_name,
5759                                 init_data->consumer_supplies[i].supply);
5760                         if (ret < 0) {
5761                                 dev_err(dev, "Failed to set supply %s\n",
5762                                         init_data->consumer_supplies[i].supply);
5763                                 goto unset_supplies;
5764                         }
5765                 }
5766         }
5767
5768         if (!rdev->desc->ops->get_voltage &&
5769             !rdev->desc->ops->list_voltage &&
5770             !rdev->desc->fixed_uV)
5771                 rdev->is_switch = true;
5772
5773         ret = device_add(&rdev->dev);
5774         if (ret != 0)
5775                 goto unset_supplies;
5776
5777         rdev_init_debugfs(rdev);
5778
5779         /* try to resolve regulators coupling since a new one was registered */
5780         mutex_lock(&regulator_list_mutex);
5781         regulator_resolve_coupling(rdev);
5782         mutex_unlock(&regulator_list_mutex);
5783
5784         /* try to resolve regulators supply since a new one was registered */
5785         class_for_each_device(&regulator_class, NULL, NULL,
5786                               regulator_register_resolve_supply);
5787         kfree(config);
5788         return rdev;
5789
5790 unset_supplies:
5791         mutex_lock(&regulator_list_mutex);
5792         unset_regulator_supplies(rdev);
5793         regulator_remove_coupling(rdev);
5794         mutex_unlock(&regulator_list_mutex);
5795 wash:
5796         regulator_put(rdev->supply);
5797         kfree(rdev->coupling_desc.coupled_rdevs);
5798         mutex_lock(&regulator_list_mutex);
5799         regulator_ena_gpio_free(rdev);
5800         mutex_unlock(&regulator_list_mutex);
5801 clean:
5802         if (dangling_of_gpiod)
5803                 gpiod_put(config->ena_gpiod);
5804         kfree(config);
5805         put_device(&rdev->dev);
5806 rinse:
5807         if (dangling_cfg_gpiod)
5808                 gpiod_put(cfg->ena_gpiod);
5809         return ERR_PTR(ret);
5810 }
5811 EXPORT_SYMBOL_GPL(regulator_register);
5812
5813 /**
5814  * regulator_unregister - unregister regulator
5815  * @rdev: regulator to unregister
5816  *
5817  * Called by regulator drivers to unregister a regulator.
5818  */
5819 void regulator_unregister(struct regulator_dev *rdev)
5820 {
5821         if (rdev == NULL)
5822                 return;
5823
5824         if (rdev->supply) {
5825                 while (rdev->use_count--)
5826                         regulator_disable(rdev->supply);
5827                 regulator_put(rdev->supply);
5828         }
5829
5830         flush_work(&rdev->disable_work.work);
5831
5832         mutex_lock(&regulator_list_mutex);
5833
5834         WARN_ON(rdev->open_count);
5835         regulator_remove_coupling(rdev);
5836         unset_regulator_supplies(rdev);
5837         list_del(&rdev->list);
5838         regulator_ena_gpio_free(rdev);
5839         device_unregister(&rdev->dev);
5840
5841         mutex_unlock(&regulator_list_mutex);
5842 }
5843 EXPORT_SYMBOL_GPL(regulator_unregister);
5844
5845 #ifdef CONFIG_SUSPEND
5846 /**
5847  * regulator_suspend - prepare regulators for system wide suspend
5848  * @dev: ``&struct device`` pointer that is passed to _regulator_suspend()
5849  *
5850  * Configure each regulator with it's suspend operating parameters for state.
5851  */
5852 static int regulator_suspend(struct device *dev)
5853 {
5854         struct regulator_dev *rdev = dev_to_rdev(dev);
5855         suspend_state_t state = pm_suspend_target_state;
5856         int ret;
5857         const struct regulator_state *rstate;
5858
5859         rstate = regulator_get_suspend_state_check(rdev, state);
5860         if (!rstate)
5861                 return 0;
5862
5863         regulator_lock(rdev);
5864         ret = __suspend_set_state(rdev, rstate);
5865         regulator_unlock(rdev);
5866
5867         return ret;
5868 }
5869
5870 static int regulator_resume(struct device *dev)
5871 {
5872         suspend_state_t state = pm_suspend_target_state;
5873         struct regulator_dev *rdev = dev_to_rdev(dev);
5874         struct regulator_state *rstate;
5875         int ret = 0;
5876
5877         rstate = regulator_get_suspend_state(rdev, state);
5878         if (rstate == NULL)
5879                 return 0;
5880
5881         /* Avoid grabbing the lock if we don't need to */
5882         if (!rdev->desc->ops->resume)
5883                 return 0;
5884
5885         regulator_lock(rdev);
5886
5887         if (rstate->enabled == ENABLE_IN_SUSPEND ||
5888             rstate->enabled == DISABLE_IN_SUSPEND)
5889                 ret = rdev->desc->ops->resume(rdev);
5890
5891         regulator_unlock(rdev);
5892
5893         return ret;
5894 }
5895 #else /* !CONFIG_SUSPEND */
5896
5897 #define regulator_suspend       NULL
5898 #define regulator_resume        NULL
5899
5900 #endif /* !CONFIG_SUSPEND */
5901
5902 #ifdef CONFIG_PM
5903 static const struct dev_pm_ops __maybe_unused regulator_pm_ops = {
5904         .suspend        = regulator_suspend,
5905         .resume         = regulator_resume,
5906 };
5907 #endif
5908
5909 const struct class regulator_class = {
5910         .name = "regulator",
5911         .dev_release = regulator_dev_release,
5912         .dev_groups = regulator_dev_groups,
5913 #ifdef CONFIG_PM
5914         .pm = &regulator_pm_ops,
5915 #endif
5916 };
5917 /**
5918  * regulator_has_full_constraints - the system has fully specified constraints
5919  *
5920  * Calling this function will cause the regulator API to disable all
5921  * regulators which have a zero use count and don't have an always_on
5922  * constraint in a late_initcall.
5923  *
5924  * The intention is that this will become the default behaviour in a
5925  * future kernel release so users are encouraged to use this facility
5926  * now.
5927  */
5928 void regulator_has_full_constraints(void)
5929 {
5930         has_full_constraints = 1;
5931 }
5932 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
5933
5934 /**
5935  * rdev_get_drvdata - get rdev regulator driver data
5936  * @rdev: regulator
5937  *
5938  * Get rdev regulator driver private data. This call can be used in the
5939  * regulator driver context.
5940  */
5941 void *rdev_get_drvdata(struct regulator_dev *rdev)
5942 {
5943         return rdev->reg_data;
5944 }
5945 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
5946
5947 /**
5948  * regulator_get_drvdata - get regulator driver data
5949  * @regulator: regulator
5950  *
5951  * Get regulator driver private data. This call can be used in the consumer
5952  * driver context when non API regulator specific functions need to be called.
5953  */
5954 void *regulator_get_drvdata(struct regulator *regulator)
5955 {
5956         return regulator->rdev->reg_data;
5957 }
5958 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
5959
5960 /**
5961  * regulator_set_drvdata - set regulator driver data
5962  * @regulator: regulator
5963  * @data: data
5964  */
5965 void regulator_set_drvdata(struct regulator *regulator, void *data)
5966 {
5967         regulator->rdev->reg_data = data;
5968 }
5969 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
5970
5971 /**
5972  * rdev_get_id - get regulator ID
5973  * @rdev: regulator
5974  */
5975 int rdev_get_id(struct regulator_dev *rdev)
5976 {
5977         return rdev->desc->id;
5978 }
5979 EXPORT_SYMBOL_GPL(rdev_get_id);
5980
5981 struct device *rdev_get_dev(struct regulator_dev *rdev)
5982 {
5983         return &rdev->dev;
5984 }
5985 EXPORT_SYMBOL_GPL(rdev_get_dev);
5986
5987 struct regmap *rdev_get_regmap(struct regulator_dev *rdev)
5988 {
5989         return rdev->regmap;
5990 }
5991 EXPORT_SYMBOL_GPL(rdev_get_regmap);
5992
5993 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
5994 {
5995         return reg_init_data->driver_data;
5996 }
5997 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
5998
5999 #ifdef CONFIG_DEBUG_FS
6000 static int supply_map_show(struct seq_file *sf, void *data)
6001 {
6002         struct regulator_map *map;
6003
6004         list_for_each_entry(map, &regulator_map_list, list) {
6005                 seq_printf(sf, "%s -> %s.%s\n",
6006                                 rdev_get_name(map->regulator), map->dev_name,
6007                                 map->supply);
6008         }
6009
6010         return 0;
6011 }
6012 DEFINE_SHOW_ATTRIBUTE(supply_map);
6013
6014 struct summary_data {
6015         struct seq_file *s;
6016         struct regulator_dev *parent;
6017         int level;
6018 };
6019
6020 static void regulator_summary_show_subtree(struct seq_file *s,
6021                                            struct regulator_dev *rdev,
6022                                            int level);
6023
6024 static int regulator_summary_show_children(struct device *dev, void *data)
6025 {
6026         struct regulator_dev *rdev = dev_to_rdev(dev);
6027         struct summary_data *summary_data = data;
6028
6029         if (rdev->supply && rdev->supply->rdev == summary_data->parent)
6030                 regulator_summary_show_subtree(summary_data->s, rdev,
6031                                                summary_data->level + 1);
6032
6033         return 0;
6034 }
6035
6036 static void regulator_summary_show_subtree(struct seq_file *s,
6037                                            struct regulator_dev *rdev,
6038                                            int level)
6039 {
6040         struct regulation_constraints *c;
6041         struct regulator *consumer;
6042         struct summary_data summary_data;
6043         unsigned int opmode;
6044
6045         if (!rdev)
6046                 return;
6047
6048         opmode = _regulator_get_mode_unlocked(rdev);
6049         seq_printf(s, "%*s%-*s %3d %4d %6d %7s ",
6050                    level * 3 + 1, "",
6051                    30 - level * 3, rdev_get_name(rdev),
6052                    rdev->use_count, rdev->open_count, rdev->bypass_count,
6053                    regulator_opmode_to_str(opmode));
6054
6055         seq_printf(s, "%5dmV ", regulator_get_voltage_rdev(rdev) / 1000);
6056         seq_printf(s, "%5dmA ",
6057                    _regulator_get_current_limit_unlocked(rdev) / 1000);
6058
6059         c = rdev->constraints;
6060         if (c) {
6061                 switch (rdev->desc->type) {
6062                 case REGULATOR_VOLTAGE:
6063                         seq_printf(s, "%5dmV %5dmV ",
6064                                    c->min_uV / 1000, c->max_uV / 1000);
6065                         break;
6066                 case REGULATOR_CURRENT:
6067                         seq_printf(s, "%5dmA %5dmA ",
6068                                    c->min_uA / 1000, c->max_uA / 1000);
6069                         break;
6070                 }
6071         }
6072
6073         seq_puts(s, "\n");
6074
6075         list_for_each_entry(consumer, &rdev->consumer_list, list) {
6076                 if (consumer->dev && consumer->dev->class == &regulator_class)
6077                         continue;
6078
6079                 seq_printf(s, "%*s%-*s ",
6080                            (level + 1) * 3 + 1, "",
6081                            30 - (level + 1) * 3,
6082                            consumer->supply_name ? consumer->supply_name :
6083                            consumer->dev ? dev_name(consumer->dev) : "deviceless");
6084
6085                 switch (rdev->desc->type) {
6086                 case REGULATOR_VOLTAGE:
6087                         seq_printf(s, "%3d %33dmA%c%5dmV %5dmV",
6088                                    consumer->enable_count,
6089                                    consumer->uA_load / 1000,
6090                                    consumer->uA_load && !consumer->enable_count ?
6091                                    '*' : ' ',
6092                                    consumer->voltage[PM_SUSPEND_ON].min_uV / 1000,
6093                                    consumer->voltage[PM_SUSPEND_ON].max_uV / 1000);
6094                         break;
6095                 case REGULATOR_CURRENT:
6096                         break;
6097                 }
6098
6099                 seq_puts(s, "\n");
6100         }
6101
6102         summary_data.s = s;
6103         summary_data.level = level;
6104         summary_data.parent = rdev;
6105
6106         class_for_each_device(&regulator_class, NULL, &summary_data,
6107                               regulator_summary_show_children);
6108 }
6109
6110 struct summary_lock_data {
6111         struct ww_acquire_ctx *ww_ctx;
6112         struct regulator_dev **new_contended_rdev;
6113         struct regulator_dev **old_contended_rdev;
6114 };
6115
6116 static int regulator_summary_lock_one(struct device *dev, void *data)
6117 {
6118         struct regulator_dev *rdev = dev_to_rdev(dev);
6119         struct summary_lock_data *lock_data = data;
6120         int ret = 0;
6121
6122         if (rdev != *lock_data->old_contended_rdev) {
6123                 ret = regulator_lock_nested(rdev, lock_data->ww_ctx);
6124
6125                 if (ret == -EDEADLK)
6126                         *lock_data->new_contended_rdev = rdev;
6127                 else
6128                         WARN_ON_ONCE(ret);
6129         } else {
6130                 *lock_data->old_contended_rdev = NULL;
6131         }
6132
6133         return ret;
6134 }
6135
6136 static int regulator_summary_unlock_one(struct device *dev, void *data)
6137 {
6138         struct regulator_dev *rdev = dev_to_rdev(dev);
6139         struct summary_lock_data *lock_data = data;
6140
6141         if (lock_data) {
6142                 if (rdev == *lock_data->new_contended_rdev)
6143                         return -EDEADLK;
6144         }
6145
6146         regulator_unlock(rdev);
6147
6148         return 0;
6149 }
6150
6151 static int regulator_summary_lock_all(struct ww_acquire_ctx *ww_ctx,
6152                                       struct regulator_dev **new_contended_rdev,
6153                                       struct regulator_dev **old_contended_rdev)
6154 {
6155         struct summary_lock_data lock_data;
6156         int ret;
6157
6158         lock_data.ww_ctx = ww_ctx;
6159         lock_data.new_contended_rdev = new_contended_rdev;
6160         lock_data.old_contended_rdev = old_contended_rdev;
6161
6162         ret = class_for_each_device(&regulator_class, NULL, &lock_data,
6163                                     regulator_summary_lock_one);
6164         if (ret)
6165                 class_for_each_device(&regulator_class, NULL, &lock_data,
6166                                       regulator_summary_unlock_one);
6167
6168         return ret;
6169 }
6170
6171 static void regulator_summary_lock(struct ww_acquire_ctx *ww_ctx)
6172 {
6173         struct regulator_dev *new_contended_rdev = NULL;
6174         struct regulator_dev *old_contended_rdev = NULL;
6175         int err;
6176
6177         mutex_lock(&regulator_list_mutex);
6178
6179         ww_acquire_init(ww_ctx, &regulator_ww_class);
6180
6181         do {
6182                 if (new_contended_rdev) {
6183                         ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
6184                         old_contended_rdev = new_contended_rdev;
6185                         old_contended_rdev->ref_cnt++;
6186                         old_contended_rdev->mutex_owner = current;
6187                 }
6188
6189                 err = regulator_summary_lock_all(ww_ctx,
6190                                                  &new_contended_rdev,
6191                                                  &old_contended_rdev);
6192
6193                 if (old_contended_rdev)
6194                         regulator_unlock(old_contended_rdev);
6195
6196         } while (err == -EDEADLK);
6197
6198         ww_acquire_done(ww_ctx);
6199 }
6200
6201 static void regulator_summary_unlock(struct ww_acquire_ctx *ww_ctx)
6202 {
6203         class_for_each_device(&regulator_class, NULL, NULL,
6204                               regulator_summary_unlock_one);
6205         ww_acquire_fini(ww_ctx);
6206
6207         mutex_unlock(&regulator_list_mutex);
6208 }
6209
6210 static int regulator_summary_show_roots(struct device *dev, void *data)
6211 {
6212         struct regulator_dev *rdev = dev_to_rdev(dev);
6213         struct seq_file *s = data;
6214
6215         if (!rdev->supply)
6216                 regulator_summary_show_subtree(s, rdev, 0);
6217
6218         return 0;
6219 }
6220
6221 static int regulator_summary_show(struct seq_file *s, void *data)
6222 {
6223         struct ww_acquire_ctx ww_ctx;
6224
6225         seq_puts(s, " regulator                      use open bypass  opmode voltage current     min     max\n");
6226         seq_puts(s, "---------------------------------------------------------------------------------------\n");
6227
6228         regulator_summary_lock(&ww_ctx);
6229
6230         class_for_each_device(&regulator_class, NULL, s,
6231                               regulator_summary_show_roots);
6232
6233         regulator_summary_unlock(&ww_ctx);
6234
6235         return 0;
6236 }
6237 DEFINE_SHOW_ATTRIBUTE(regulator_summary);
6238 #endif /* CONFIG_DEBUG_FS */
6239
6240 static int __init regulator_init(void)
6241 {
6242         int ret;
6243
6244         ret = class_register(&regulator_class);
6245
6246         debugfs_root = debugfs_create_dir("regulator", NULL);
6247         if (IS_ERR(debugfs_root))
6248                 pr_debug("regulator: Failed to create debugfs directory\n");
6249
6250 #ifdef CONFIG_DEBUG_FS
6251         debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
6252                             &supply_map_fops);
6253
6254         debugfs_create_file("regulator_summary", 0444, debugfs_root,
6255                             NULL, &regulator_summary_fops);
6256 #endif
6257         regulator_dummy_init();
6258
6259         regulator_coupler_register(&generic_regulator_coupler);
6260
6261         return ret;
6262 }
6263
6264 /* init early to allow our consumers to complete system booting */
6265 core_initcall(regulator_init);
6266
6267 static int regulator_late_cleanup(struct device *dev, void *data)
6268 {
6269         struct regulator_dev *rdev = dev_to_rdev(dev);
6270         struct regulation_constraints *c = rdev->constraints;
6271         int ret;
6272
6273         if (c && c->always_on)
6274                 return 0;
6275
6276         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS))
6277                 return 0;
6278
6279         regulator_lock(rdev);
6280
6281         if (rdev->use_count)
6282                 goto unlock;
6283
6284         /* If reading the status failed, assume that it's off. */
6285         if (_regulator_is_enabled(rdev) <= 0)
6286                 goto unlock;
6287
6288         if (have_full_constraints()) {
6289                 /* We log since this may kill the system if it goes
6290                  * wrong.
6291                  */
6292                 rdev_info(rdev, "disabling\n");
6293                 ret = _regulator_do_disable(rdev);
6294                 if (ret != 0)
6295                         rdev_err(rdev, "couldn't disable: %pe\n", ERR_PTR(ret));
6296         } else {
6297                 /* The intention is that in future we will
6298                  * assume that full constraints are provided
6299                  * so warn even if we aren't going to do
6300                  * anything here.
6301                  */
6302                 rdev_warn(rdev, "incomplete constraints, leaving on\n");
6303         }
6304
6305 unlock:
6306         regulator_unlock(rdev);
6307
6308         return 0;
6309 }
6310
6311 static bool regulator_ignore_unused;
6312 static int __init regulator_ignore_unused_setup(char *__unused)
6313 {
6314         regulator_ignore_unused = true;
6315         return 1;
6316 }
6317 __setup("regulator_ignore_unused", regulator_ignore_unused_setup);
6318
6319 static void regulator_init_complete_work_function(struct work_struct *work)
6320 {
6321         /*
6322          * Regulators may had failed to resolve their input supplies
6323          * when were registered, either because the input supply was
6324          * not registered yet or because its parent device was not
6325          * bound yet. So attempt to resolve the input supplies for
6326          * pending regulators before trying to disable unused ones.
6327          */
6328         class_for_each_device(&regulator_class, NULL, NULL,
6329                               regulator_register_resolve_supply);
6330
6331         /*
6332          * For debugging purposes, it may be useful to prevent unused
6333          * regulators from being disabled.
6334          */
6335         if (regulator_ignore_unused) {
6336                 pr_warn("regulator: Not disabling unused regulators\n");
6337                 return;
6338         }
6339
6340         /* If we have a full configuration then disable any regulators
6341          * we have permission to change the status for and which are
6342          * not in use or always_on.  This is effectively the default
6343          * for DT and ACPI as they have full constraints.
6344          */
6345         class_for_each_device(&regulator_class, NULL, NULL,
6346                               regulator_late_cleanup);
6347 }
6348
6349 static DECLARE_DELAYED_WORK(regulator_init_complete_work,
6350                             regulator_init_complete_work_function);
6351
6352 static int __init regulator_init_complete(void)
6353 {
6354         /*
6355          * Since DT doesn't provide an idiomatic mechanism for
6356          * enabling full constraints and since it's much more natural
6357          * with DT to provide them just assume that a DT enabled
6358          * system has full constraints.
6359          */
6360         if (of_have_populated_dt())
6361                 has_full_constraints = true;
6362
6363         /*
6364          * We punt completion for an arbitrary amount of time since
6365          * systems like distros will load many drivers from userspace
6366          * so consumers might not always be ready yet, this is
6367          * particularly an issue with laptops where this might bounce
6368          * the display off then on.  Ideally we'd get a notification
6369          * from userspace when this happens but we don't so just wait
6370          * a bit and hope we waited long enough.  It'd be better if
6371          * we'd only do this on systems that need it, and a kernel
6372          * command line option might be useful.
6373          */
6374         schedule_delayed_work(&regulator_init_complete_work,
6375                               msecs_to_jiffies(30000));
6376
6377         return 0;
6378 }
6379 late_initcall_sync(regulator_init_complete);