drivers/acpi/scan.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * scan.c - support for transforming the ACPI namespace into individual objects
   4  */
   5
   6 #define pr_fmt(fmt) "ACPI: " fmt
   7
   8 #include <linux/module.h>
   9 #include <linux/init.h>
  10 #include <linux/slab.h>
  11 #include <linux/kernel.h>
  12 #include <linux/acpi.h>
  13 #include <linux/acpi_iort.h>
  14 #include <linux/acpi_viot.h>
  15 #include <linux/iommu.h>
  16 #include <linux/signal.h>
  17 #include <linux/kthread.h>
  18 #include <linux/dmi.h>
  19 #include <linux/dma-map-ops.h>
  20 #include <linux/platform_data/x86/apple.h>
  21 #include <linux/pgtable.h>
  22 #include <linux/crc32.h>
  23 #include <linux/dma-direct.h>
  24
  25 #include "internal.h"
  26 #include "sleep.h"
  27
  28 #define ACPI_BUS_CLASS                  "system_bus"
  29 #define ACPI_BUS_HID                    "LNXSYBUS"
  30 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  31
  32 #define INVALID_ACPI_HANDLE     ((acpi_handle)ZERO_PAGE(0))
  33
  34 static const char *dummy_hid = "device";
  35
  36 static LIST_HEAD(acpi_dep_list);
  37 static DEFINE_MUTEX(acpi_dep_list_lock);
  38 LIST_HEAD(acpi_bus_id_list);
  39 static DEFINE_MUTEX(acpi_scan_lock);
  40 static LIST_HEAD(acpi_scan_handlers_list);
  41 DEFINE_MUTEX(acpi_device_lock);
  42 LIST_HEAD(acpi_wakeup_device_list);
  43 static DEFINE_MUTEX(acpi_hp_context_lock);
  44
  45 /*
  46  * The UART device described by the SPCR table is the only object which needs
  47  * special-casing. Everything else is covered by ACPI namespace paths in STAO
  48  * table.
  49  */
  50 static u64 spcr_uart_addr;
  51
  52 void acpi_scan_lock_acquire(void)
  53 {
  54         mutex_lock(&acpi_scan_lock);
  55 }
  56 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  57
  58 void acpi_scan_lock_release(void)
  59 {
  60         mutex_unlock(&acpi_scan_lock);
  61 }
  62 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  63
  64 void acpi_lock_hp_context(void)
  65 {
  66         mutex_lock(&acpi_hp_context_lock);
  67 }
  68
  69 void acpi_unlock_hp_context(void)
  70 {
  71         mutex_unlock(&acpi_hp_context_lock);
  72 }
  73
  74 void acpi_initialize_hp_context(struct acpi_device *adev,
  75                                 struct acpi_hotplug_context *hp,
  76                                 int (*notify)(struct acpi_device *, u32),
  77                                 void (*uevent)(struct acpi_device *, u32))
  78 {
  79         acpi_lock_hp_context();
  80         hp->notify = notify;
  81         hp->uevent = uevent;
  82         acpi_set_hp_context(adev, hp);
  83         acpi_unlock_hp_context();
  84 }
  85 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  86
  87 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  88 {
  89         if (!handler)
  90                 return -EINVAL;
  91
  92         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  93         return 0;
  94 }
  95
  96 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
  97                                        const char *hotplug_profile_name)
  98 {
  99         int error;
 100
 101         error = acpi_scan_add_handler(handler);
 102         if (error)
 103                 return error;
 104
 105         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 106         return 0;
 107 }
 108
 109 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 110 {
 111         struct acpi_device_physical_node *pn;
 112         bool offline = true;
 113         char *envp[] = { "EVENT=offline", NULL };
 114
 115         /*
 116          * acpi_container_offline() calls this for all of the container's
 117          * children under the container's physical_node_lock lock.
 118          */
 119         mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
 120
 121         list_for_each_entry(pn, &adev->physical_node_list, node)
 122                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 123                         if (uevent)
 124                                 kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
 125
 126                         offline = false;
 127                         break;
 128                 }
 129
 130         mutex_unlock(&adev->physical_node_lock);
 131         return offline;
 132 }
 133
 134 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 135                                     void **ret_p)
 136 {
 137         struct acpi_device *device = acpi_fetch_acpi_dev(handle);
 138         struct acpi_device_physical_node *pn;
 139         bool second_pass = (bool)data;
 140         acpi_status status = AE_OK;
 141
 142         if (!device)
 143                 return AE_OK;
 144
 145         if (device->handler && !device->handler->hotplug.enabled) {
 146                 *ret_p = &device->dev;
 147                 return AE_SUPPORT;
 148         }
 149
 150         mutex_lock(&device->physical_node_lock);
 151
 152         list_for_each_entry(pn, &device->physical_node_list, node) {
 153                 int ret;
 154
 155                 if (second_pass) {
 156                         /* Skip devices offlined by the first pass. */
 157                         if (pn->put_online)
 158                                 continue;
 159                 } else {
 160                         pn->put_online = false;
 161                 }
 162                 ret = device_offline(pn->dev);
 163                 if (ret >= 0) {
 164                         pn->put_online = !ret;
 165                 } else {
 166                         *ret_p = pn->dev;
 167                         if (second_pass) {
 168                                 status = AE_ERROR;
 169                                 break;
 170                         }
 171                 }
 172         }
 173
 174         mutex_unlock(&device->physical_node_lock);
 175
 176         return status;
 177 }
 178
 179 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 180                                    void **ret_p)
 181 {
 182         struct acpi_device *device = acpi_fetch_acpi_dev(handle);
 183         struct acpi_device_physical_node *pn;
 184
 185         if (!device)
 186                 return AE_OK;
 187
 188         mutex_lock(&device->physical_node_lock);
 189
 190         list_for_each_entry(pn, &device->physical_node_list, node)
 191                 if (pn->put_online) {
 192                         device_online(pn->dev);
 193                         pn->put_online = false;
 194                 }
 195
 196         mutex_unlock(&device->physical_node_lock);
 197
 198         return AE_OK;
 199 }
 200
 201 static int acpi_scan_try_to_offline(struct acpi_device *device)
 202 {
 203         acpi_handle handle = device->handle;
 204         struct device *errdev = NULL;
 205         acpi_status status;
 206
 207         /*
 208          * Carry out two passes here and ignore errors in the first pass,
 209          * because if the devices in question are memory blocks and
 210          * CONFIG_MEMCG is set, one of the blocks may hold data structures
 211          * that the other blocks depend on, but it is not known in advance which
 212          * block holds them.
 213          *
 214          * If the first pass is successful, the second one isn't needed, though.
 215          */
 216         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 217                                      NULL, acpi_bus_offline, (void *)false,
 218                                      (void **)&errdev);
 219         if (status == AE_SUPPORT) {
 220                 dev_warn(errdev, "Offline disabled.\n");
 221                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 222                                     acpi_bus_online, NULL, NULL, NULL);
 223                 return -EPERM;
 224         }
 225         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 226         if (errdev) {
 227                 errdev = NULL;
 228                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 229                                     NULL, acpi_bus_offline, (void *)true,
 230                                     (void **)&errdev);
 231                 if (!errdev)
 232                         acpi_bus_offline(handle, 0, (void *)true,
 233                                          (void **)&errdev);
 234
 235                 if (errdev) {
 236                         dev_warn(errdev, "Offline failed.\n");
 237                         acpi_bus_online(handle, 0, NULL, NULL);
 238                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 239                                             ACPI_UINT32_MAX, acpi_bus_online,
 240                                             NULL, NULL, NULL);
 241                         return -EBUSY;
 242                 }
 243         }
 244         return 0;
 245 }
 246
 247 static int acpi_scan_hot_remove(struct acpi_device *device)
 248 {
 249         acpi_handle handle = device->handle;
 250         unsigned long long sta;
 251         acpi_status status;
 252
 253         if (device->handler && device->handler->hotplug.demand_offline) {
 254                 if (!acpi_scan_is_offline(device, true))
 255                         return -EBUSY;
 256         } else {
 257                 int error = acpi_scan_try_to_offline(device);
 258                 if (error)
 259                         return error;
 260         }
 261
 262         acpi_handle_debug(handle, "Ejecting\n");
 263
 264         acpi_bus_trim(device);
 265
 266         acpi_evaluate_lck(handle, 0);
 267         /*
 268          * TBD: _EJD support.
 269          */
 270         status = acpi_evaluate_ej0(handle);
 271         if (status == AE_NOT_FOUND)
 272                 return -ENODEV;
 273         else if (ACPI_FAILURE(status))
 274                 return -EIO;
 275
 276         /*
 277          * Verify if eject was indeed successful.  If not, log an error
 278          * message.  No need to call _OST since _EJ0 call was made OK.
 279          */
 280         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 281         if (ACPI_FAILURE(status)) {
 282                 acpi_handle_warn(handle,
 283                         "Status check after eject failed (0x%x)\n", status);
 284         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 285                 acpi_handle_warn(handle,
 286                         "Eject incomplete - status 0x%llx\n", sta);
 287         }
 288
 289         return 0;
 290 }
 291
 292 static int acpi_scan_device_not_enumerated(struct acpi_device *adev)
 293 {
 294         if (!acpi_device_enumerated(adev)) {
 295                 dev_warn(&adev->dev, "Still not enumerated\n");
 296                 return -EALREADY;
 297         }
 298         acpi_bus_trim(adev);
 299         return 0;
 300 }
 301
 302 static int acpi_scan_device_check(struct acpi_device *adev)
 303 {
 304         int error;
 305
 306         acpi_bus_get_status(adev);
 307         if (acpi_device_is_present(adev)) {
 308                 /*
 309                  * This function is only called for device objects for which
 310                  * matching scan handlers exist.  The only situation in which
 311                  * the scan handler is not attached to this device object yet
 312                  * is when the device has just appeared (either it wasn't
 313                  * present at all before or it was removed and then added
 314                  * again).
 315                  */
 316                 if (adev->handler) {
 317                         dev_warn(&adev->dev, "Already enumerated\n");
 318                         return -EALREADY;
 319                 }
 320                 error = acpi_bus_scan(adev->handle);
 321                 if (error) {
 322                         dev_warn(&adev->dev, "Namespace scan failure\n");
 323                         return error;
 324                 }
 325                 if (!adev->handler) {
 326                         dev_warn(&adev->dev, "Enumeration failure\n");
 327                         error = -ENODEV;
 328                 }
 329         } else {
 330                 error = acpi_scan_device_not_enumerated(adev);
 331         }
 332         return error;
 333 }
 334
 335 static int acpi_scan_bus_check(struct acpi_device *adev, void *not_used)
 336 {
 337         struct acpi_scan_handler *handler = adev->handler;
 338         int error;
 339
 340         acpi_bus_get_status(adev);
 341         if (!acpi_device_is_present(adev)) {
 342                 acpi_scan_device_not_enumerated(adev);
 343                 return 0;
 344         }
 345         if (handler && handler->hotplug.scan_dependent)
 346                 return handler->hotplug.scan_dependent(adev);
 347
 348         error = acpi_bus_scan(adev->handle);
 349         if (error) {
 350                 dev_warn(&adev->dev, "Namespace scan failure\n");
 351                 return error;
 352         }
 353         return acpi_dev_for_each_child(adev, acpi_scan_bus_check, NULL);
 354 }
 355
 356 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
 357 {
 358         switch (type) {
 359         case ACPI_NOTIFY_BUS_CHECK:
 360                 return acpi_scan_bus_check(adev, NULL);
 361         case ACPI_NOTIFY_DEVICE_CHECK:
 362                 return acpi_scan_device_check(adev);
 363         case ACPI_NOTIFY_EJECT_REQUEST:
 364         case ACPI_OST_EC_OSPM_EJECT:
 365                 if (adev->handler && !adev->handler->hotplug.enabled) {
 366                         dev_info(&adev->dev, "Eject disabled\n");
 367                         return -EPERM;
 368                 }
 369                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
 370                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 371                 return acpi_scan_hot_remove(adev);
 372         }
 373         return -EINVAL;
 374 }
 375
 376 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
 377 {
 378         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 379         int error = -ENODEV;
 380
 381         lock_device_hotplug();
 382         mutex_lock(&acpi_scan_lock);
 383
 384         /*
 385          * The device object's ACPI handle cannot become invalid as long as we
 386          * are holding acpi_scan_lock, but it might have become invalid before
 387          * that lock was acquired.
 388          */
 389         if (adev->handle == INVALID_ACPI_HANDLE)
 390                 goto err_out;
 391
 392         if (adev->flags.is_dock_station) {
 393                 error = dock_notify(adev, src);
 394         } else if (adev->flags.hotplug_notify) {
 395                 error = acpi_generic_hotplug_event(adev, src);
 396         } else {
 397                 int (*notify)(struct acpi_device *, u32);
 398
 399                 acpi_lock_hp_context();
 400                 notify = adev->hp ? adev->hp->notify : NULL;
 401                 acpi_unlock_hp_context();
 402                 /*
 403                  * There may be additional notify handlers for device objects
 404                  * without the .event() callback, so ignore them here.
 405                  */
 406                 if (notify)
 407                         error = notify(adev, src);
 408                 else
 409                         goto out;
 410         }
 411         switch (error) {
 412         case 0:
 413                 ost_code = ACPI_OST_SC_SUCCESS;
 414                 break;
 415         case -EPERM:
 416                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 417                 break;
 418         case -EBUSY:
 419                 ost_code = ACPI_OST_SC_DEVICE_BUSY;
 420                 break;
 421         default:
 422                 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 423                 break;
 424         }
 425
 426  err_out:
 427         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 428
 429  out:
 430         acpi_put_acpi_dev(adev);
 431         mutex_unlock(&acpi_scan_lock);
 432         unlock_device_hotplug();
 433 }
 434
 435 static void acpi_free_power_resources_lists(struct acpi_device *device)
 436 {
 437         int i;
 438
 439         if (device->wakeup.flags.valid)
 440                 acpi_power_resources_list_free(&device->wakeup.resources);
 441
 442         if (!device->power.flags.power_resources)
 443                 return;
 444
 445         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 446                 struct acpi_device_power_state *ps = &device->power.states[i];
 447                 acpi_power_resources_list_free(&ps->resources);
 448         }
 449 }
 450
 451 static void acpi_device_release(struct device *dev)
 452 {
 453         struct acpi_device *acpi_dev = to_acpi_device(dev);
 454
 455         acpi_free_properties(acpi_dev);
 456         acpi_free_pnp_ids(&acpi_dev->pnp);
 457         acpi_free_power_resources_lists(acpi_dev);
 458         kfree(acpi_dev);
 459 }
 460
 461 static void acpi_device_del(struct acpi_device *device)
 462 {
 463         struct acpi_device_bus_id *acpi_device_bus_id;
 464
 465         mutex_lock(&acpi_device_lock);
 466
 467         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
 468                 if (!strcmp(acpi_device_bus_id->bus_id,
 469                             acpi_device_hid(device))) {
 470                         ida_free(&acpi_device_bus_id->instance_ida,
 471                                  device->pnp.instance_no);
 472                         if (ida_is_empty(&acpi_device_bus_id->instance_ida)) {
 473                                 list_del(&acpi_device_bus_id->node);
 474                                 kfree_const(acpi_device_bus_id->bus_id);
 475                                 kfree(acpi_device_bus_id);
 476                         }
 477                         break;
 478                 }
 479
 480         list_del(&device->wakeup_list);
 481
 482         mutex_unlock(&acpi_device_lock);
 483
 484         acpi_power_add_remove_device(device, false);
 485         acpi_device_remove_files(device);
 486         if (device->remove)
 487                 device->remove(device);
 488
 489         device_del(&device->dev);
 490 }
 491
 492 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
 493
 494 static LIST_HEAD(acpi_device_del_list);
 495 static DEFINE_MUTEX(acpi_device_del_lock);
 496
 497 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
 498 {
 499         for (;;) {
 500                 struct acpi_device *adev;
 501
 502                 mutex_lock(&acpi_device_del_lock);
 503
 504                 if (list_empty(&acpi_device_del_list)) {
 505                         mutex_unlock(&acpi_device_del_lock);
 506                         break;
 507                 }
 508                 adev = list_first_entry(&acpi_device_del_list,
 509                                         struct acpi_device, del_list);
 510                 list_del(&adev->del_list);
 511
 512                 mutex_unlock(&acpi_device_del_lock);
 513
 514                 blocking_notifier_call_chain(&acpi_reconfig_chain,
 515                                              ACPI_RECONFIG_DEVICE_REMOVE, adev);
 516
 517                 acpi_device_del(adev);
 518                 /*
 519                  * Drop references to all power resources that might have been
 520                  * used by the device.
 521                  */
 522                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
 523                 acpi_dev_put(adev);
 524         }
 525 }
 526
 527 /**
 528  * acpi_scan_drop_device - Drop an ACPI device object.
 529  * @handle: Handle of an ACPI namespace node, not used.
 530  * @context: Address of the ACPI device object to drop.
 531  *
 532  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
 533  * namespace node the device object pointed to by @context is attached to.
 534  *
 535  * The unregistration is carried out asynchronously to avoid running
 536  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
 537  * ensure the correct ordering (the device objects must be unregistered in the
 538  * same order in which the corresponding namespace nodes are deleted).
 539  */
 540 static void acpi_scan_drop_device(acpi_handle handle, void *context)
 541 {
 542         static DECLARE_WORK(work, acpi_device_del_work_fn);
 543         struct acpi_device *adev = context;
 544
 545         mutex_lock(&acpi_device_del_lock);
 546
 547         /*
 548          * Use the ACPI hotplug workqueue which is ordered, so this work item
 549          * won't run after any hotplug work items submitted subsequently.  That
 550          * prevents attempts to register device objects identical to those being
 551          * deleted from happening concurrently (such attempts result from
 552          * hotplug events handled via the ACPI hotplug workqueue).  It also will
 553          * run after all of the work items submitted previously, which helps
 554          * those work items to ensure that they are not accessing stale device
 555          * objects.
 556          */
 557         if (list_empty(&acpi_device_del_list))
 558                 acpi_queue_hotplug_work(&work);
 559
 560         list_add_tail(&adev->del_list, &acpi_device_del_list);
 561         /* Make acpi_ns_validate_handle() return NULL for this handle. */
 562         adev->handle = INVALID_ACPI_HANDLE;
 563
 564         mutex_unlock(&acpi_device_del_lock);
 565 }
 566
 567 static struct acpi_device *handle_to_device(acpi_handle handle,
 568                                             void (*callback)(void *))
 569 {
 570         struct acpi_device *adev = NULL;
 571         acpi_status status;
 572
 573         status = acpi_get_data_full(handle, acpi_scan_drop_device,
 574                                     (void **)&adev, callback);
 575         if (ACPI_FAILURE(status) || !adev) {
 576                 acpi_handle_debug(handle, "No context!\n");
 577                 return NULL;
 578         }
 579         return adev;
 580 }
 581
 582 /**
 583  * acpi_fetch_acpi_dev - Retrieve ACPI device object.
 584  * @handle: ACPI handle associated with the requested ACPI device object.
 585  *
 586  * Return a pointer to the ACPI device object associated with @handle, if
 587  * present, or NULL otherwise.
 588  */
 589 struct acpi_device *acpi_fetch_acpi_dev(acpi_handle handle)
 590 {
 591         return handle_to_device(handle, NULL);
 592 }
 593 EXPORT_SYMBOL_GPL(acpi_fetch_acpi_dev);
 594
 595 static void get_acpi_device(void *dev)
 596 {
 597         acpi_dev_get(dev);
 598 }
 599
 600 /**
 601  * acpi_get_acpi_dev - Retrieve ACPI device object and reference count it.
 602  * @handle: ACPI handle associated with the requested ACPI device object.
 603  *
 604  * Return a pointer to the ACPI device object associated with @handle and bump
 605  * up that object's reference counter (under the ACPI Namespace lock), if
 606  * present, or return NULL otherwise.
 607  *
 608  * The ACPI device object reference acquired by this function needs to be
 609  * dropped via acpi_dev_put().
 610  */
 611 struct acpi_device *acpi_get_acpi_dev(acpi_handle handle)
 612 {
 613         return handle_to_device(handle, get_acpi_device);
 614 }
 615 EXPORT_SYMBOL_GPL(acpi_get_acpi_dev);
 616
 617 static struct acpi_device_bus_id *acpi_device_bus_id_match(const char *dev_id)
 618 {
 619         struct acpi_device_bus_id *acpi_device_bus_id;
 620
 621         /* Find suitable bus_id and instance number in acpi_bus_id_list. */
 622         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 623                 if (!strcmp(acpi_device_bus_id->bus_id, dev_id))
 624                         return acpi_device_bus_id;
 625         }
 626         return NULL;
 627 }
 628
 629 static int acpi_device_set_name(struct acpi_device *device,
 630                                 struct acpi_device_bus_id *acpi_device_bus_id)
 631 {
 632         struct ida *instance_ida = &acpi_device_bus_id->instance_ida;
 633         int result;
 634
 635         result = ida_alloc(instance_ida, GFP_KERNEL);
 636         if (result < 0)
 637                 return result;
 638
 639         device->pnp.instance_no = result;
 640         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, result);
 641         return 0;
 642 }
 643
 644 int acpi_tie_acpi_dev(struct acpi_device *adev)
 645 {
 646         acpi_handle handle = adev->handle;
 647         acpi_status status;
 648
 649         if (!handle)
 650                 return 0;
 651
 652         status = acpi_attach_data(handle, acpi_scan_drop_device, adev);
 653         if (ACPI_FAILURE(status)) {
 654                 acpi_handle_err(handle, "Unable to attach device data\n");
 655                 return -ENODEV;
 656         }
 657
 658         return 0;
 659 }
 660
 661 static void acpi_store_pld_crc(struct acpi_device *adev)
 662 {
 663         struct acpi_pld_info *pld;
 664         acpi_status status;
 665
 666         status = acpi_get_physical_device_location(adev->handle, &pld);
 667         if (ACPI_FAILURE(status))
 668                 return;
 669
 670         adev->pld_crc = crc32(~0, pld, sizeof(*pld));
 671         ACPI_FREE(pld);
 672 }
 673
 674 int acpi_device_add(struct acpi_device *device)
 675 {
 676         struct acpi_device_bus_id *acpi_device_bus_id;
 677         int result;
 678
 679         /*
 680          * Linkage
 681          * -------
 682          * Link this device to its parent and siblings.
 683          */
 684         INIT_LIST_HEAD(&device->wakeup_list);
 685         INIT_LIST_HEAD(&device->physical_node_list);
 686         INIT_LIST_HEAD(&device->del_list);
 687         mutex_init(&device->physical_node_lock);
 688
 689         mutex_lock(&acpi_device_lock);
 690
 691         acpi_device_bus_id = acpi_device_bus_id_match(acpi_device_hid(device));
 692         if (acpi_device_bus_id) {
 693                 result = acpi_device_set_name(device, acpi_device_bus_id);
 694                 if (result)
 695                         goto err_unlock;
 696         } else {
 697                 acpi_device_bus_id = kzalloc(sizeof(*acpi_device_bus_id),
 698                                              GFP_KERNEL);
 699                 if (!acpi_device_bus_id) {
 700                         result = -ENOMEM;
 701                         goto err_unlock;
 702                 }
 703                 acpi_device_bus_id->bus_id =
 704                         kstrdup_const(acpi_device_hid(device), GFP_KERNEL);
 705                 if (!acpi_device_bus_id->bus_id) {
 706                         kfree(acpi_device_bus_id);
 707                         result = -ENOMEM;
 708                         goto err_unlock;
 709                 }
 710
 711                 ida_init(&acpi_device_bus_id->instance_ida);
 712
 713                 result = acpi_device_set_name(device, acpi_device_bus_id);
 714                 if (result) {
 715                         kfree_const(acpi_device_bus_id->bus_id);
 716                         kfree(acpi_device_bus_id);
 717                         goto err_unlock;
 718                 }
 719
 720                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 721         }
 722
 723         if (device->wakeup.flags.valid)
 724                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 725
 726         acpi_store_pld_crc(device);
 727
 728         mutex_unlock(&acpi_device_lock);
 729
 730         result = device_add(&device->dev);
 731         if (result) {
 732                 dev_err(&device->dev, "Error registering device\n");
 733                 goto err;
 734         }
 735
 736         result = acpi_device_setup_files(device);
 737         if (result)
 738                 pr_err("Error creating sysfs interface for device %s\n",
 739                        dev_name(&device->dev));
 740
 741         return 0;
 742
 743 err:
 744         mutex_lock(&acpi_device_lock);
 745
 746         list_del(&device->wakeup_list);
 747
 748 err_unlock:
 749         mutex_unlock(&acpi_device_lock);
 750
 751         acpi_detach_data(device->handle, acpi_scan_drop_device);
 752
 753         return result;
 754 }
 755
 756 /* --------------------------------------------------------------------------
 757                                  Device Enumeration
 758    -------------------------------------------------------------------------- */
 759 static bool acpi_info_matches_ids(struct acpi_device_info *info,
 760                                   const char * const ids[])
 761 {
 762         struct acpi_pnp_device_id_list *cid_list = NULL;
 763         int i, index;
 764
 765         if (!(info->valid & ACPI_VALID_HID))
 766                 return false;
 767
 768         index = match_string(ids, -1, info->hardware_id.string);
 769         if (index >= 0)
 770                 return true;
 771
 772         if (info->valid & ACPI_VALID_CID)
 773                 cid_list = &info->compatible_id_list;
 774
 775         if (!cid_list)
 776                 return false;
 777
 778         for (i = 0; i < cid_list->count; i++) {
 779                 index = match_string(ids, -1, cid_list->ids[i].string);
 780                 if (index >= 0)
 781                         return true;
 782         }
 783
 784         return false;
 785 }
 786
 787 /* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */
 788 static const char * const acpi_ignore_dep_ids[] = {
 789         "PNP0D80", /* Windows-compatible System Power Management Controller */
 790         "INT33BD", /* Intel Baytrail Mailbox Device */
 791         "LATT2021", /* Lattice FW Update Client Driver */
 792         NULL
 793 };
 794
 795 /* List of HIDs for which we honor deps of matching ACPI devs, when checking _DEP lists. */
 796 static const char * const acpi_honor_dep_ids[] = {
 797         "INT3472", /* Camera sensor PMIC / clk and regulator info */
 798         "INTC1059", /* IVSC (TGL) driver must be loaded to allow i2c access to camera sensors */
 799         "INTC1095", /* IVSC (ADL) driver must be loaded to allow i2c access to camera sensors */
 800         "INTC100A", /* IVSC (RPL) driver must be loaded to allow i2c access to camera sensors */
 801         NULL
 802 };
 803
 804 static struct acpi_device *acpi_find_parent_acpi_dev(acpi_handle handle)
 805 {
 806         struct acpi_device *adev;
 807
 808         /*
 809          * Fixed hardware devices do not appear in the namespace and do not
 810          * have handles, but we fabricate acpi_devices for them, so we have
 811          * to deal with them specially.
 812          */
 813         if (!handle)
 814                 return acpi_root;
 815
 816         do {
 817                 acpi_status status;
 818
 819                 status = acpi_get_parent(handle, &handle);
 820                 if (ACPI_FAILURE(status)) {
 821                         if (status != AE_NULL_ENTRY)
 822                                 return acpi_root;
 823
 824                         return NULL;
 825                 }
 826                 adev = acpi_fetch_acpi_dev(handle);
 827         } while (!adev);
 828         return adev;
 829 }
 830
 831 acpi_status
 832 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 833 {
 834         acpi_status status;
 835         acpi_handle tmp;
 836         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 837         union acpi_object *obj;
 838
 839         status = acpi_get_handle(handle, "_EJD", &tmp);
 840         if (ACPI_FAILURE(status))
 841                 return status;
 842
 843         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 844         if (ACPI_SUCCESS(status)) {
 845                 obj = buffer.pointer;
 846                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 847                                          ejd);
 848                 kfree(buffer.pointer);
 849         }
 850         return status;
 851 }
 852 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 853
 854 static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev)
 855 {
 856         acpi_handle handle = dev->handle;
 857         struct acpi_device_wakeup *wakeup = &dev->wakeup;
 858         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 859         union acpi_object *package = NULL;
 860         union acpi_object *element = NULL;
 861         acpi_status status;
 862         int err = -ENODATA;
 863
 864         INIT_LIST_HEAD(&wakeup->resources);
 865
 866         /* _PRW */
 867         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 868         if (ACPI_FAILURE(status)) {
 869                 acpi_handle_info(handle, "_PRW evaluation failed: %s\n",
 870                                  acpi_format_exception(status));
 871                 return err;
 872         }
 873
 874         package = (union acpi_object *)buffer.pointer;
 875
 876         if (!package || package->package.count < 2)
 877                 goto out;
 878
 879         element = &(package->package.elements[0]);
 880         if (!element)
 881                 goto out;
 882
 883         if (element->type == ACPI_TYPE_PACKAGE) {
 884                 if ((element->package.count < 2) ||
 885                     (element->package.elements[0].type !=
 886                      ACPI_TYPE_LOCAL_REFERENCE)
 887                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 888                         goto out;
 889
 890                 wakeup->gpe_device =
 891                     element->package.elements[0].reference.handle;
 892                 wakeup->gpe_number =
 893                     (u32) element->package.elements[1].integer.value;
 894         } else if (element->type == ACPI_TYPE_INTEGER) {
 895                 wakeup->gpe_device = NULL;
 896                 wakeup->gpe_number = element->integer.value;
 897         } else {
 898                 goto out;
 899         }
 900
 901         element = &(package->package.elements[1]);
 902         if (element->type != ACPI_TYPE_INTEGER)
 903                 goto out;
 904
 905         wakeup->sleep_state = element->integer.value;
 906
 907         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
 908         if (err)
 909                 goto out;
 910
 911         if (!list_empty(&wakeup->resources)) {
 912                 int sleep_state;
 913
 914                 err = acpi_power_wakeup_list_init(&wakeup->resources,
 915                                                   &sleep_state);
 916                 if (err) {
 917                         acpi_handle_warn(handle, "Retrieving current states "
 918                                          "of wakeup power resources failed\n");
 919                         acpi_power_resources_list_free(&wakeup->resources);
 920                         goto out;
 921                 }
 922                 if (sleep_state < wakeup->sleep_state) {
 923                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
 924                                          "(S%d) by S%d from power resources\n",
 925                                          (int)wakeup->sleep_state, sleep_state);
 926                         wakeup->sleep_state = sleep_state;
 927                 }
 928         }
 929
 930  out:
 931         kfree(buffer.pointer);
 932         return err;
 933 }
 934
 935 /* Do not use a button for S5 wakeup */
 936 #define ACPI_AVOID_WAKE_FROM_S5         BIT(0)
 937
 938 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
 939 {
 940         static const struct acpi_device_id button_device_ids[] = {
 941                 {"PNP0C0C", 0},                         /* Power button */
 942                 {"PNP0C0D", ACPI_AVOID_WAKE_FROM_S5},   /* Lid */
 943                 {"PNP0C0E", ACPI_AVOID_WAKE_FROM_S5},   /* Sleep button */
 944                 {"", 0},
 945         };
 946         struct acpi_device_wakeup *wakeup = &device->wakeup;
 947         const struct acpi_device_id *match;
 948         acpi_status status;
 949
 950         wakeup->flags.notifier_present = 0;
 951
 952         /* Power button, Lid switch always enable wakeup */
 953         match = acpi_match_acpi_device(button_device_ids, device);
 954         if (match) {
 955                 if ((match->driver_data & ACPI_AVOID_WAKE_FROM_S5) &&
 956                     wakeup->sleep_state == ACPI_STATE_S5)
 957                         wakeup->sleep_state = ACPI_STATE_S4;
 958                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
 959                 device_set_wakeup_capable(&device->dev, true);
 960                 return true;
 961         }
 962
 963         status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
 964                                          wakeup->gpe_number);
 965         return ACPI_SUCCESS(status);
 966 }
 967
 968 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 969 {
 970         int err;
 971
 972         /* Presence of _PRW indicates wake capable */
 973         if (!acpi_has_method(device->handle, "_PRW"))
 974                 return;
 975
 976         err = acpi_bus_extract_wakeup_device_power_package(device);
 977         if (err) {
 978                 dev_err(&device->dev, "Unable to extract wakeup power resources");
 979                 return;
 980         }
 981
 982         device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
 983         device->wakeup.prepare_count = 0;
 984         /*
 985          * Call _PSW/_DSW object to disable its ability to wake the sleeping
 986          * system for the ACPI device with the _PRW object.
 987          * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
 988          * So it is necessary to call _DSW object first. Only when it is not
 989          * present will the _PSW object used.
 990          */
 991         err = acpi_device_sleep_wake(device, 0, 0, 0);
 992         if (err)
 993                 pr_debug("error in _DSW or _PSW evaluation\n");
 994 }
 995
 996 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
 997 {
 998         struct acpi_device_power_state *ps = &device->power.states[state];
 999         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1000         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1001         acpi_status status;
1002
1003         INIT_LIST_HEAD(&ps->resources);
1004
1005         /* Evaluate "_PRx" to get referenced power resources */
1006         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1007         if (ACPI_SUCCESS(status)) {
1008                 union acpi_object *package = buffer.pointer;
1009
1010                 if (buffer.length && package
1011                     && package->type == ACPI_TYPE_PACKAGE
1012                     && package->package.count)
1013                         acpi_extract_power_resources(package, 0, &ps->resources);
1014
1015                 ACPI_FREE(buffer.pointer);
1016         }
1017
1018         /* Evaluate "_PSx" to see if we can do explicit sets */
1019         pathname[2] = 'S';
1020         if (acpi_has_method(device->handle, pathname))
1021                 ps->flags.explicit_set = 1;
1022
1023         /* State is valid if there are means to put the device into it. */
1024         if (!list_empty(&ps->resources) || ps->flags.explicit_set)
1025                 ps->flags.valid = 1;
1026
1027         ps->power = -1;         /* Unknown - driver assigned */
1028         ps->latency = -1;       /* Unknown - driver assigned */
1029 }
1030
1031 static void acpi_bus_get_power_flags(struct acpi_device *device)
1032 {
1033         unsigned long long dsc = ACPI_STATE_D0;
1034         u32 i;
1035
1036         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1037         if (!acpi_has_method(device->handle, "_PS0") &&
1038             !acpi_has_method(device->handle, "_PR0"))
1039                 return;
1040
1041         device->flags.power_manageable = 1;
1042
1043         /*
1044          * Power Management Flags
1045          */
1046         if (acpi_has_method(device->handle, "_PSC"))
1047                 device->power.flags.explicit_get = 1;
1048
1049         if (acpi_has_method(device->handle, "_IRC"))
1050                 device->power.flags.inrush_current = 1;
1051
1052         if (acpi_has_method(device->handle, "_DSW"))
1053                 device->power.flags.dsw_present = 1;
1054
1055         acpi_evaluate_integer(device->handle, "_DSC", NULL, &dsc);
1056         device->power.state_for_enumeration = dsc;
1057
1058         /*
1059          * Enumerate supported power management states
1060          */
1061         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1062                 acpi_bus_init_power_state(device, i);
1063
1064         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1065
1066         /* Set the defaults for D0 and D3hot (always supported). */
1067         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1068         device->power.states[ACPI_STATE_D0].power = 100;
1069         device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
1070
1071         /*
1072          * Use power resources only if the D0 list of them is populated, because
1073          * some platforms may provide _PR3 only to indicate D3cold support and
1074          * in those cases the power resources list returned by it may be bogus.
1075          */
1076         if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) {
1077                 device->power.flags.power_resources = 1;
1078                 /*
1079                  * D3cold is supported if the D3hot list of power resources is
1080                  * not empty.
1081                  */
1082                 if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
1083                         device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1084         }
1085
1086         if (acpi_bus_init_power(device))
1087                 device->flags.power_manageable = 0;
1088 }
1089
1090 static void acpi_bus_get_flags(struct acpi_device *device)
1091 {
1092         /* Presence of _STA indicates 'dynamic_status' */
1093         if (acpi_has_method(device->handle, "_STA"))
1094                 device->flags.dynamic_status = 1;
1095
1096         /* Presence of _RMV indicates 'removable' */
1097         if (acpi_has_method(device->handle, "_RMV"))
1098                 device->flags.removable = 1;
1099
1100         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1101         if (acpi_has_method(device->handle, "_EJD") ||
1102             acpi_has_method(device->handle, "_EJ0"))
1103                 device->flags.ejectable = 1;
1104 }
1105
1106 static void acpi_device_get_busid(struct acpi_device *device)
1107 {
1108         char bus_id[5] = { '?', 0 };
1109         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1110         int i = 0;
1111
1112         /*
1113          * Bus ID
1114          * ------
1115          * The device's Bus ID is simply the object name.
1116          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1117          */
1118         if (!acpi_dev_parent(device)) {
1119                 strcpy(device->pnp.bus_id, "ACPI");
1120                 return;
1121         }
1122
1123         switch (device->device_type) {
1124         case ACPI_BUS_TYPE_POWER_BUTTON:
1125                 strcpy(device->pnp.bus_id, "PWRF");
1126                 break;
1127         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1128                 strcpy(device->pnp.bus_id, "SLPF");
1129                 break;
1130         case ACPI_BUS_TYPE_ECDT_EC:
1131                 strcpy(device->pnp.bus_id, "ECDT");
1132                 break;
1133         default:
1134                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1135                 /* Clean up trailing underscores (if any) */
1136                 for (i = 3; i > 1; i--) {
1137                         if (bus_id[i] == '_')
1138                                 bus_id[i] = '\0';
1139                         else
1140                                 break;
1141                 }
1142                 strcpy(device->pnp.bus_id, bus_id);
1143                 break;
1144         }
1145 }
1146
1147 /*
1148  * acpi_ata_match - see if an acpi object is an ATA device
1149  *
1150  * If an acpi object has one of the ACPI ATA methods defined,
1151  * then we can safely call it an ATA device.
1152  */
1153 bool acpi_ata_match(acpi_handle handle)
1154 {
1155         return acpi_has_method(handle, "_GTF") ||
1156                acpi_has_method(handle, "_GTM") ||
1157                acpi_has_method(handle, "_STM") ||
1158                acpi_has_method(handle, "_SDD");
1159 }
1160
1161 /*
1162  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1163  *
1164  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1165  * then we can safely call it an ejectable drive bay
1166  */
1167 bool acpi_bay_match(acpi_handle handle)
1168 {
1169         acpi_handle phandle;
1170
1171         if (!acpi_has_method(handle, "_EJ0"))
1172                 return false;
1173         if (acpi_ata_match(handle))
1174                 return true;
1175         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1176                 return false;
1177
1178         return acpi_ata_match(phandle);
1179 }
1180
1181 bool acpi_device_is_battery(struct acpi_device *adev)
1182 {
1183         struct acpi_hardware_id *hwid;
1184
1185         list_for_each_entry(hwid, &adev->pnp.ids, list)
1186                 if (!strcmp("PNP0C0A", hwid->id))
1187                         return true;
1188
1189         return false;
1190 }
1191
1192 static bool is_ejectable_bay(struct acpi_device *adev)
1193 {
1194         acpi_handle handle = adev->handle;
1195
1196         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1197                 return true;
1198
1199         return acpi_bay_match(handle);
1200 }
1201
1202 /*
1203  * acpi_dock_match - see if an acpi object has a _DCK method
1204  */
1205 bool acpi_dock_match(acpi_handle handle)
1206 {
1207         return acpi_has_method(handle, "_DCK");
1208 }
1209
1210 static acpi_status
1211 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1212                           void **return_value)
1213 {
1214         long *cap = context;
1215
1216         if (acpi_has_method(handle, "_BCM") &&
1217             acpi_has_method(handle, "_BCL")) {
1218                 acpi_handle_debug(handle, "Found generic backlight support\n");
1219                 *cap |= ACPI_VIDEO_BACKLIGHT;
1220                 /* We have backlight support, no need to scan further */
1221                 return AE_CTRL_TERMINATE;
1222         }
1223         return 0;
1224 }
1225
1226 /* Returns true if the ACPI object is a video device which can be
1227  * handled by video.ko.
1228  * The device will get a Linux specific CID added in scan.c to
1229  * identify the device as an ACPI graphics device
1230  * Be aware that the graphics device may not be physically present
1231  * Use acpi_video_get_capabilities() to detect general ACPI video
1232  * capabilities of present cards
1233  */
1234 long acpi_is_video_device(acpi_handle handle)
1235 {
1236         long video_caps = 0;
1237
1238         /* Is this device able to support video switching ? */
1239         if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1240                 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1241
1242         /* Is this device able to retrieve a video ROM ? */
1243         if (acpi_has_method(handle, "_ROM"))
1244                 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1245
1246         /* Is this device able to configure which video head to be POSTed ? */
1247         if (acpi_has_method(handle, "_VPO") &&
1248             acpi_has_method(handle, "_GPD") &&
1249             acpi_has_method(handle, "_SPD"))
1250                 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1251
1252         /* Only check for backlight functionality if one of the above hit. */
1253         if (video_caps)
1254                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1255                                     ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1256                                     &video_caps, NULL);
1257
1258         return video_caps;
1259 }
1260 EXPORT_SYMBOL(acpi_is_video_device);
1261
1262 const char *acpi_device_hid(struct acpi_device *device)
1263 {
1264         struct acpi_hardware_id *hid;
1265
1266         if (list_empty(&device->pnp.ids))
1267                 return dummy_hid;
1268
1269         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1270         return hid->id;
1271 }
1272 EXPORT_SYMBOL(acpi_device_hid);
1273
1274 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1275 {
1276         struct acpi_hardware_id *id;
1277
1278         id = kmalloc(sizeof(*id), GFP_KERNEL);
1279         if (!id)
1280                 return;
1281
1282         id->id = kstrdup_const(dev_id, GFP_KERNEL);
1283         if (!id->id) {
1284                 kfree(id);
1285                 return;
1286         }
1287
1288         list_add_tail(&id->list, &pnp->ids);
1289         pnp->type.hardware_id = 1;
1290 }
1291
1292 /*
1293  * Old IBM workstations have a DSDT bug wherein the SMBus object
1294  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1295  * prefix.  Work around this.
1296  */
1297 static bool acpi_ibm_smbus_match(acpi_handle handle)
1298 {
1299         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1300         struct acpi_buffer path = { sizeof(node_name), node_name };
1301
1302         if (!dmi_name_in_vendors("IBM"))
1303                 return false;
1304
1305         /* Look for SMBS object */
1306         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1307             strcmp("SMBS", path.pointer))
1308                 return false;
1309
1310         /* Does it have the necessary (but misnamed) methods? */
1311         if (acpi_has_method(handle, "SBI") &&
1312             acpi_has_method(handle, "SBR") &&
1313             acpi_has_method(handle, "SBW"))
1314                 return true;
1315
1316         return false;
1317 }
1318
1319 static bool acpi_object_is_system_bus(acpi_handle handle)
1320 {
1321         acpi_handle tmp;
1322
1323         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1324             tmp == handle)
1325                 return true;
1326         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1327             tmp == handle)
1328                 return true;
1329
1330         return false;
1331 }
1332
1333 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1334                              int device_type)
1335 {
1336         struct acpi_device_info *info = NULL;
1337         struct acpi_pnp_device_id_list *cid_list;
1338         int i;
1339
1340         switch (device_type) {
1341         case ACPI_BUS_TYPE_DEVICE:
1342                 if (handle == ACPI_ROOT_OBJECT) {
1343                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1344                         break;
1345                 }
1346
1347                 acpi_get_object_info(handle, &info);
1348                 if (!info) {
1349                         pr_err("%s: Error reading device info\n", __func__);
1350                         return;
1351                 }
1352
1353                 if (info->valid & ACPI_VALID_HID) {
1354                         acpi_add_id(pnp, info->hardware_id.string);
1355                         pnp->type.platform_id = 1;
1356                 }
1357                 if (info->valid & ACPI_VALID_CID) {
1358                         cid_list = &info->compatible_id_list;
1359                         for (i = 0; i < cid_list->count; i++)
1360                                 acpi_add_id(pnp, cid_list->ids[i].string);
1361                 }
1362                 if (info->valid & ACPI_VALID_ADR) {
1363                         pnp->bus_address = info->address;
1364                         pnp->type.bus_address = 1;
1365                 }
1366                 if (info->valid & ACPI_VALID_UID)
1367                         pnp->unique_id = kstrdup(info->unique_id.string,
1368                                                         GFP_KERNEL);
1369                 if (info->valid & ACPI_VALID_CLS)
1370                         acpi_add_id(pnp, info->class_code.string);
1371
1372                 kfree(info);
1373
1374                 /*
1375                  * Some devices don't reliably have _HIDs & _CIDs, so add
1376                  * synthetic HIDs to make sure drivers can find them.
1377                  */
1378                 if (acpi_is_video_device(handle)) {
1379                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1380                         pnp->type.backlight = 1;
1381                         break;
1382                 }
1383                 if (acpi_bay_match(handle))
1384                         acpi_add_id(pnp, ACPI_BAY_HID);
1385                 else if (acpi_dock_match(handle))
1386                         acpi_add_id(pnp, ACPI_DOCK_HID);
1387                 else if (acpi_ibm_smbus_match(handle))
1388                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1389                 else if (list_empty(&pnp->ids) &&
1390                          acpi_object_is_system_bus(handle)) {
1391                         /* \_SB, \_TZ, LNXSYBUS */
1392                         acpi_add_id(pnp, ACPI_BUS_HID);
1393                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1394                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1395                 }
1396
1397                 break;
1398         case ACPI_BUS_TYPE_POWER:
1399                 acpi_add_id(pnp, ACPI_POWER_HID);
1400                 break;
1401         case ACPI_BUS_TYPE_PROCESSOR:
1402                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1403                 break;
1404         case ACPI_BUS_TYPE_THERMAL:
1405                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1406                 break;
1407         case ACPI_BUS_TYPE_POWER_BUTTON:
1408                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1409                 break;
1410         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1411                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1412                 break;
1413         case ACPI_BUS_TYPE_ECDT_EC:
1414                 acpi_add_id(pnp, ACPI_ECDT_HID);
1415                 break;
1416         }
1417 }
1418
1419 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1420 {
1421         struct acpi_hardware_id *id, *tmp;
1422
1423         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1424                 kfree_const(id->id);
1425                 kfree(id);
1426         }
1427         kfree(pnp->unique_id);
1428 }
1429
1430 /**
1431  * acpi_dma_supported - Check DMA support for the specified device.
1432  * @adev: The pointer to acpi device
1433  *
1434  * Return false if DMA is not supported. Otherwise, return true
1435  */
1436 bool acpi_dma_supported(const struct acpi_device *adev)
1437 {
1438         if (!adev)
1439                 return false;
1440
1441         if (adev->flags.cca_seen)
1442                 return true;
1443
1444         /*
1445         * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1446         * DMA on "Intel platforms".  Presumably that includes all x86 and
1447         * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1448         */
1449         if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1450                 return true;
1451
1452         return false;
1453 }
1454
1455 /**
1456  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1457  * @adev: The pointer to acpi device
1458  *
1459  * Return enum dev_dma_attr.
1460  */
1461 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1462 {
1463         if (!acpi_dma_supported(adev))
1464                 return DEV_DMA_NOT_SUPPORTED;
1465
1466         if (adev->flags.coherent_dma)
1467                 return DEV_DMA_COHERENT;
1468         else
1469                 return DEV_DMA_NON_COHERENT;
1470 }
1471
1472 /**
1473  * acpi_dma_get_range() - Get device DMA parameters.
1474  *
1475  * @dev: device to configure
1476  * @map: pointer to DMA ranges result
1477  *
1478  * Evaluate DMA regions and return pointer to DMA regions on
1479  * parsing success; it does not update the passed in values on failure.
1480  *
1481  * Return 0 on success, < 0 on failure.
1482  */
1483 int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map)
1484 {
1485         struct acpi_device *adev;
1486         LIST_HEAD(list);
1487         struct resource_entry *rentry;
1488         int ret;
1489         struct device *dma_dev = dev;
1490         struct bus_dma_region *r;
1491
1492         /*
1493          * Walk the device tree chasing an ACPI companion with a _DMA
1494          * object while we go. Stop if we find a device with an ACPI
1495          * companion containing a _DMA method.
1496          */
1497         do {
1498                 adev = ACPI_COMPANION(dma_dev);
1499                 if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1500                         break;
1501
1502                 dma_dev = dma_dev->parent;
1503         } while (dma_dev);
1504
1505         if (!dma_dev)
1506                 return -ENODEV;
1507
1508         if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1509                 acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1510                 return -EINVAL;
1511         }
1512
1513         ret = acpi_dev_get_dma_resources(adev, &list);
1514         if (ret > 0) {
1515                 r = kcalloc(ret + 1, sizeof(*r), GFP_KERNEL);
1516                 if (!r) {
1517                         ret = -ENOMEM;
1518                         goto out;
1519                 }
1520
1521                 *map = r;
1522
1523                 list_for_each_entry(rentry, &list, node) {
1524                         if (rentry->res->start >= rentry->res->end) {
1525                                 kfree(*map);
1526                                 *map = NULL;
1527                                 ret = -EINVAL;
1528                                 dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1529                                 goto out;
1530                         }
1531
1532                         r->cpu_start = rentry->res->start;
1533                         r->dma_start = rentry->res->start - rentry->offset;
1534                         r->size = resource_size(rentry->res);
1535                         r++;
1536                 }
1537         }
1538  out:
1539         acpi_dev_free_resource_list(&list);
1540
1541         return ret >= 0 ? 0 : ret;
1542 }
1543
1544 #ifdef CONFIG_IOMMU_API
1545 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1546                            struct fwnode_handle *fwnode,
1547                            const struct iommu_ops *ops)
1548 {
1549         int ret = iommu_fwspec_init(dev, fwnode, ops);
1550
1551         if (!ret)
1552                 ret = iommu_fwspec_add_ids(dev, &id, 1);
1553
1554         return ret;
1555 }
1556
1557 static inline const struct iommu_ops *acpi_iommu_fwspec_ops(struct device *dev)
1558 {
1559         struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
1560
1561         return fwspec ? fwspec->ops : NULL;
1562 }
1563
1564 static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
1565 {
1566         int err;
1567         const struct iommu_ops *ops;
1568
1569         /* Serialise to make dev->iommu stable under our potential fwspec */
1570         mutex_lock(&iommu_probe_device_lock);
1571         /*
1572          * If we already translated the fwspec there is nothing left to do,
1573          * return the iommu_ops.
1574          */
1575         ops = acpi_iommu_fwspec_ops(dev);
1576         if (ops) {
1577                 mutex_unlock(&iommu_probe_device_lock);
1578                 return 0;
1579         }
1580
1581         err = iort_iommu_configure_id(dev, id_in);
1582         if (err && err != -EPROBE_DEFER)
1583                 err = viot_iommu_configure(dev);
1584         mutex_unlock(&iommu_probe_device_lock);
1585
1586         /*
1587          * If we have reason to believe the IOMMU driver missed the initial
1588          * iommu_probe_device() call for dev, replay it to get things in order.
1589          */
1590         if (!err && dev->bus)
1591                 err = iommu_probe_device(dev);
1592
1593         /* Ignore all other errors apart from EPROBE_DEFER */
1594         if (err == -EPROBE_DEFER) {
1595                 return err;
1596         } else if (err) {
1597                 dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
1598                 return -ENODEV;
1599         }
1600         if (!acpi_iommu_fwspec_ops(dev))
1601                 return -ENODEV;
1602         return 0;
1603 }
1604
1605 #else /* !CONFIG_IOMMU_API */
1606
1607 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1608                            struct fwnode_handle *fwnode,
1609                            const struct iommu_ops *ops)
1610 {
1611         return -ENODEV;
1612 }
1613
1614 static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
1615 {
1616         return -ENODEV;
1617 }
1618
1619 #endif /* !CONFIG_IOMMU_API */
1620
1621 /**
1622  * acpi_dma_configure_id - Set-up DMA configuration for the device.
1623  * @dev: The pointer to the device
1624  * @attr: device dma attributes
1625  * @input_id: input device id const value pointer
1626  */
1627 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
1628                           const u32 *input_id)
1629 {
1630         int ret;
1631
1632         if (attr == DEV_DMA_NOT_SUPPORTED) {
1633                 set_dma_ops(dev, &dma_dummy_ops);
1634                 return 0;
1635         }
1636
1637         acpi_arch_dma_setup(dev);
1638
1639         ret = acpi_iommu_configure_id(dev, input_id);
1640         if (ret == -EPROBE_DEFER)
1641                 return -EPROBE_DEFER;
1642
1643         /*
1644          * Historically this routine doesn't fail driver probing due to errors
1645          * in acpi_iommu_configure_id()
1646          */
1647
1648         arch_setup_dma_ops(dev, 0, U64_MAX, attr == DEV_DMA_COHERENT);
1649
1650         return 0;
1651 }
1652 EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
1653
1654 static void acpi_init_coherency(struct acpi_device *adev)
1655 {
1656         unsigned long long cca = 0;
1657         acpi_status status;
1658         struct acpi_device *parent = acpi_dev_parent(adev);
1659
1660         if (parent && parent->flags.cca_seen) {
1661                 /*
1662                  * From ACPI spec, OSPM will ignore _CCA if an ancestor
1663                  * already saw one.
1664                  */
1665                 adev->flags.cca_seen = 1;
1666                 cca = parent->flags.coherent_dma;
1667         } else {
1668                 status = acpi_evaluate_integer(adev->handle, "_CCA",
1669                                                NULL, &cca);
1670                 if (ACPI_SUCCESS(status))
1671                         adev->flags.cca_seen = 1;
1672                 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1673                         /*
1674                          * If architecture does not specify that _CCA is
1675                          * required for DMA-able devices (e.g. x86),
1676                          * we default to _CCA=1.
1677                          */
1678                         cca = 1;
1679                 else
1680                         acpi_handle_debug(adev->handle,
1681                                           "ACPI device is missing _CCA.\n");
1682         }
1683
1684         adev->flags.coherent_dma = cca;
1685 }
1686
1687 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1688 {
1689         bool *is_serial_bus_slave_p = data;
1690
1691         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1692                 return 1;
1693
1694         *is_serial_bus_slave_p = true;
1695
1696          /* no need to do more checking */
1697         return -1;
1698 }
1699
1700 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1701 {
1702         struct acpi_device *parent = acpi_dev_parent(device);
1703         static const struct acpi_device_id indirect_io_hosts[] = {
1704                 {"HISI0191", 0},
1705                 {}
1706         };
1707
1708         return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1709 }
1710
1711 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1712 {
1713         struct list_head resource_list;
1714         bool is_serial_bus_slave = false;
1715         static const struct acpi_device_id ignore_serial_bus_ids[] = {
1716         /*
1717          * These devices have multiple SerialBus resources and a client
1718          * device must be instantiated for each of them, each with
1719          * its own device id.
1720          * Normally we only instantiate one client device for the first
1721          * resource, using the ACPI HID as id. These special cases are handled
1722          * by the drivers/platform/x86/serial-multi-instantiate.c driver, which
1723          * knows which client device id to use for each resource.
1724          */
1725                 {"BSG1160", },
1726                 {"BSG2150", },
1727                 {"CSC3551", },
1728                 {"CSC3554", },
1729                 {"CSC3556", },
1730                 {"CSC3557", },
1731                 {"INT33FE", },
1732                 {"INT3515", },
1733                 /* Non-conforming _HID for Cirrus Logic already released */
1734                 {"CLSA0100", },
1735                 {"CLSA0101", },
1736         /*
1737          * Some ACPI devs contain SerialBus resources even though they are not
1738          * attached to a serial bus at all.
1739          */
1740                 {ACPI_VIDEO_HID, },
1741                 {"MSHW0028", },
1742         /*
1743          * HIDs of device with an UartSerialBusV2 resource for which userspace
1744          * expects a regular tty cdev to be created (instead of the in kernel
1745          * serdev) and which have a kernel driver which expects a platform_dev
1746          * such as the rfkill-gpio driver.
1747          */
1748                 {"BCM4752", },
1749                 {"LNV4752", },
1750                 {}
1751         };
1752
1753         if (acpi_is_indirect_io_slave(device))
1754                 return true;
1755
1756         /* Macs use device properties in lieu of _CRS resources */
1757         if (x86_apple_machine &&
1758             (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1759              fwnode_property_present(&device->fwnode, "i2cAddress") ||
1760              fwnode_property_present(&device->fwnode, "baud")))
1761                 return true;
1762
1763         if (!acpi_match_device_ids(device, ignore_serial_bus_ids))
1764                 return false;
1765
1766         INIT_LIST_HEAD(&resource_list);
1767         acpi_dev_get_resources(device, &resource_list,
1768                                acpi_check_serial_bus_slave,
1769                                &is_serial_bus_slave);
1770         acpi_dev_free_resource_list(&resource_list);
1771
1772         return is_serial_bus_slave;
1773 }
1774
1775 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1776                              int type, void (*release)(struct device *))
1777 {
1778         struct acpi_device *parent = acpi_find_parent_acpi_dev(handle);
1779
1780         INIT_LIST_HEAD(&device->pnp.ids);
1781         device->device_type = type;
1782         device->handle = handle;
1783         device->dev.parent = parent ? &parent->dev : NULL;
1784         device->dev.release = release;
1785         device->dev.bus = &acpi_bus_type;
1786         fwnode_init(&device->fwnode, &acpi_device_fwnode_ops);
1787         acpi_set_device_status(device, ACPI_STA_DEFAULT);
1788         acpi_device_get_busid(device);
1789         acpi_set_pnp_ids(handle, &device->pnp, type);
1790         acpi_init_properties(device);
1791         acpi_bus_get_flags(device);
1792         device->flags.match_driver = false;
1793         device->flags.initialized = true;
1794         device->flags.enumeration_by_parent =
1795                 acpi_device_enumeration_by_parent(device);
1796         acpi_device_clear_enumerated(device);
1797         device_initialize(&device->dev);
1798         dev_set_uevent_suppress(&device->dev, true);
1799         acpi_init_coherency(device);
1800 }
1801
1802 static void acpi_scan_dep_init(struct acpi_device *adev)
1803 {
1804         struct acpi_dep_data *dep;
1805
1806         list_for_each_entry(dep, &acpi_dep_list, node) {
1807                 if (dep->consumer == adev->handle) {
1808                         if (dep->honor_dep)
1809                                 adev->flags.honor_deps = 1;
1810
1811                         adev->dep_unmet++;
1812                 }
1813         }
1814 }
1815
1816 void acpi_device_add_finalize(struct acpi_device *device)
1817 {
1818         dev_set_uevent_suppress(&device->dev, false);
1819         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1820 }
1821
1822 static void acpi_scan_init_status(struct acpi_device *adev)
1823 {
1824         if (acpi_bus_get_status(adev))
1825                 acpi_set_device_status(adev, 0);
1826 }
1827
1828 static int acpi_add_single_object(struct acpi_device **child,
1829                                   acpi_handle handle, int type, bool dep_init)
1830 {
1831         struct acpi_device *device;
1832         bool release_dep_lock = false;
1833         int result;
1834
1835         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1836         if (!device)
1837                 return -ENOMEM;
1838
1839         acpi_init_device_object(device, handle, type, acpi_device_release);
1840         /*
1841          * Getting the status is delayed till here so that we can call
1842          * acpi_bus_get_status() and use its quirk handling.  Note that
1843          * this must be done before the get power-/wakeup_dev-flags calls.
1844          */
1845         if (type == ACPI_BUS_TYPE_DEVICE || type == ACPI_BUS_TYPE_PROCESSOR) {
1846                 if (dep_init) {
1847                         mutex_lock(&acpi_dep_list_lock);
1848                         /*
1849                          * Hold the lock until the acpi_tie_acpi_dev() call
1850                          * below to prevent concurrent acpi_scan_clear_dep()
1851                          * from deleting a dependency list entry without
1852                          * updating dep_unmet for the device.
1853                          */
1854                         release_dep_lock = true;
1855                         acpi_scan_dep_init(device);
1856                 }
1857                 acpi_scan_init_status(device);
1858         }
1859
1860         acpi_bus_get_power_flags(device);
1861         acpi_bus_get_wakeup_device_flags(device);
1862
1863         result = acpi_tie_acpi_dev(device);
1864
1865         if (release_dep_lock)
1866                 mutex_unlock(&acpi_dep_list_lock);
1867
1868         if (!result)
1869                 result = acpi_device_add(device);
1870
1871         if (result) {
1872                 acpi_device_release(&device->dev);
1873                 return result;
1874         }
1875
1876         acpi_power_add_remove_device(device, true);
1877         acpi_device_add_finalize(device);
1878
1879         acpi_handle_debug(handle, "Added as %s, parent %s\n",
1880                           dev_name(&device->dev), device->dev.parent ?
1881                                 dev_name(device->dev.parent) : "(null)");
1882
1883         *child = device;
1884         return 0;
1885 }
1886
1887 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1888                                             void *context)
1889 {
1890         struct resource *res = context;
1891
1892         if (acpi_dev_resource_memory(ares, res))
1893                 return AE_CTRL_TERMINATE;
1894
1895         return AE_OK;
1896 }
1897
1898 static bool acpi_device_should_be_hidden(acpi_handle handle)
1899 {
1900         acpi_status status;
1901         struct resource res;
1902
1903         /* Check if it should ignore the UART device */
1904         if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1905                 return false;
1906
1907         /*
1908          * The UART device described in SPCR table is assumed to have only one
1909          * memory resource present. So we only look for the first one here.
1910          */
1911         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1912                                      acpi_get_resource_memory, &res);
1913         if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1914                 return false;
1915
1916         acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1917                          &res.start);
1918
1919         return true;
1920 }
1921
1922 bool acpi_device_is_present(const struct acpi_device *adev)
1923 {
1924         return adev->status.present || adev->status.functional;
1925 }
1926
1927 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1928                                        const char *idstr,
1929                                        const struct acpi_device_id **matchid)
1930 {
1931         const struct acpi_device_id *devid;
1932
1933         if (handler->match)
1934                 return handler->match(idstr, matchid);
1935
1936         for (devid = handler->ids; devid->id[0]; devid++)
1937                 if (!strcmp((char *)devid->id, idstr)) {
1938                         if (matchid)
1939                                 *matchid = devid;
1940
1941                         return true;
1942                 }
1943
1944         return false;
1945 }
1946
1947 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1948                                         const struct acpi_device_id **matchid)
1949 {
1950         struct acpi_scan_handler *handler;
1951
1952         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1953                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1954                         return handler;
1955
1956         return NULL;
1957 }
1958
1959 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1960 {
1961         if (!!hotplug->enabled == !!val)
1962                 return;
1963
1964         mutex_lock(&acpi_scan_lock);
1965
1966         hotplug->enabled = val;
1967
1968         mutex_unlock(&acpi_scan_lock);
1969 }
1970
1971 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1972 {
1973         struct acpi_hardware_id *hwid;
1974
1975         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1976                 acpi_dock_add(adev);
1977                 return;
1978         }
1979         list_for_each_entry(hwid, &adev->pnp.ids, list) {
1980                 struct acpi_scan_handler *handler;
1981
1982                 handler = acpi_scan_match_handler(hwid->id, NULL);
1983                 if (handler) {
1984                         adev->flags.hotplug_notify = true;
1985                         break;
1986                 }
1987         }
1988 }
1989
1990 static u32 acpi_scan_check_dep(acpi_handle handle)
1991 {
1992         struct acpi_handle_list dep_devices;
1993         u32 count;
1994         int i;
1995
1996         /*
1997          * Check for _HID here to avoid deferring the enumeration of:
1998          * 1. PCI devices.
1999          * 2. ACPI nodes describing USB ports.
2000          * Still, checking for _HID catches more then just these cases ...
2001          */
2002         if (!acpi_has_method(handle, "_DEP") || !acpi_has_method(handle, "_HID"))
2003                 return 0;
2004
2005         if (!acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices)) {
2006                 acpi_handle_debug(handle, "Failed to evaluate _DEP.\n");
2007                 return 0;
2008         }
2009
2010         for (count = 0, i = 0; i < dep_devices.count; i++) {
2011                 struct acpi_device_info *info;
2012                 struct acpi_dep_data *dep;
2013                 bool skip, honor_dep;
2014                 acpi_status status;
2015
2016                 status = acpi_get_object_info(dep_devices.handles[i], &info);
2017                 if (ACPI_FAILURE(status)) {
2018                         acpi_handle_debug(handle, "Error reading _DEP device info\n");
2019                         continue;
2020                 }
2021
2022                 skip = acpi_info_matches_ids(info, acpi_ignore_dep_ids);
2023                 honor_dep = acpi_info_matches_ids(info, acpi_honor_dep_ids);
2024                 kfree(info);
2025
2026                 if (skip)
2027                         continue;
2028
2029                 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
2030                 if (!dep)
2031                         continue;
2032
2033                 count++;
2034
2035                 dep->supplier = dep_devices.handles[i];
2036                 dep->consumer = handle;
2037                 dep->honor_dep = honor_dep;
2038
2039                 mutex_lock(&acpi_dep_list_lock);
2040                 list_add_tail(&dep->node , &acpi_dep_list);
2041                 mutex_unlock(&acpi_dep_list_lock);
2042         }
2043
2044         acpi_handle_list_free(&dep_devices);
2045         return count;
2046 }
2047
2048 static acpi_status acpi_scan_check_crs_csi2_cb(acpi_handle handle, u32 a, void *b, void **c)
2049 {
2050         acpi_mipi_check_crs_csi2(handle);
2051         return AE_OK;
2052 }
2053
2054 static acpi_status acpi_bus_check_add(acpi_handle handle, bool first_pass,
2055                                       struct acpi_device **adev_p)
2056 {
2057         struct acpi_device *device = acpi_fetch_acpi_dev(handle);
2058         acpi_object_type acpi_type;
2059         int type;
2060
2061         if (device)
2062                 goto out;
2063
2064         if (ACPI_FAILURE(acpi_get_type(handle, &acpi_type)))
2065                 return AE_OK;
2066
2067         switch (acpi_type) {
2068         case ACPI_TYPE_DEVICE:
2069                 if (acpi_device_should_be_hidden(handle))
2070                         return AE_OK;
2071
2072                 if (first_pass) {
2073                         acpi_mipi_check_crs_csi2(handle);
2074
2075                         /* Bail out if there are dependencies. */
2076                         if (acpi_scan_check_dep(handle) > 0) {
2077                                 /*
2078                                  * The entire CSI-2 connection graph needs to be
2079                                  * extracted before any drivers or scan handlers
2080                                  * are bound to struct device objects, so scan
2081                                  * _CRS CSI-2 resource descriptors for all
2082                                  * devices below the current handle.
2083                                  */
2084                                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
2085                                                     ACPI_UINT32_MAX,
2086                                                     acpi_scan_check_crs_csi2_cb,
2087                                                     NULL, NULL, NULL);
2088                                 return AE_CTRL_DEPTH;
2089                         }
2090                 }
2091
2092                 fallthrough;
2093         case ACPI_TYPE_ANY:     /* for ACPI_ROOT_OBJECT */
2094                 type = ACPI_BUS_TYPE_DEVICE;
2095                 break;
2096
2097         case ACPI_TYPE_PROCESSOR:
2098                 type = ACPI_BUS_TYPE_PROCESSOR;
2099                 break;
2100
2101         case ACPI_TYPE_THERMAL:
2102                 type = ACPI_BUS_TYPE_THERMAL;
2103                 break;
2104
2105         case ACPI_TYPE_POWER:
2106                 acpi_add_power_resource(handle);
2107                 fallthrough;
2108         default:
2109                 return AE_OK;
2110         }
2111
2112         /*
2113          * If first_pass is true at this point, the device has no dependencies,
2114          * or the creation of the device object would have been postponed above.
2115          */
2116         acpi_add_single_object(&device, handle, type, !first_pass);
2117         if (!device)
2118                 return AE_CTRL_DEPTH;
2119
2120         acpi_scan_init_hotplug(device);
2121
2122 out:
2123         if (!*adev_p)
2124                 *adev_p = device;
2125
2126         return AE_OK;
2127 }
2128
2129 static acpi_status acpi_bus_check_add_1(acpi_handle handle, u32 lvl_not_used,
2130                                         void *not_used, void **ret_p)
2131 {
2132         return acpi_bus_check_add(handle, true, (struct acpi_device **)ret_p);
2133 }
2134
2135 static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used,
2136                                         void *not_used, void **ret_p)
2137 {
2138         return acpi_bus_check_add(handle, false, (struct acpi_device **)ret_p);
2139 }
2140
2141 static void acpi_default_enumeration(struct acpi_device *device)
2142 {
2143         /*
2144          * Do not enumerate devices with enumeration_by_parent flag set as
2145          * they will be enumerated by their respective parents.
2146          */
2147         if (!device->flags.enumeration_by_parent) {
2148                 acpi_create_platform_device(device, NULL);
2149                 acpi_device_set_enumerated(device);
2150         } else {
2151                 blocking_notifier_call_chain(&acpi_reconfig_chain,
2152                                              ACPI_RECONFIG_DEVICE_ADD, device);
2153         }
2154 }
2155
2156 static const struct acpi_device_id generic_device_ids[] = {
2157         {ACPI_DT_NAMESPACE_HID, },
2158         {"", },
2159 };
2160
2161 static int acpi_generic_device_attach(struct acpi_device *adev,
2162                                       const struct acpi_device_id *not_used)
2163 {
2164         /*
2165          * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
2166          * below can be unconditional.
2167          */
2168         if (adev->data.of_compatible)
2169                 acpi_default_enumeration(adev);
2170
2171         return 1;
2172 }
2173
2174 static struct acpi_scan_handler generic_device_handler = {
2175         .ids = generic_device_ids,
2176         .attach = acpi_generic_device_attach,
2177 };
2178
2179 static int acpi_scan_attach_handler(struct acpi_device *device)
2180 {
2181         struct acpi_hardware_id *hwid;
2182         int ret = 0;
2183
2184         list_for_each_entry(hwid, &device->pnp.ids, list) {
2185                 const struct acpi_device_id *devid;
2186                 struct acpi_scan_handler *handler;
2187
2188                 handler = acpi_scan_match_handler(hwid->id, &devid);
2189                 if (handler) {
2190                         if (!handler->attach) {
2191                                 device->pnp.type.platform_id = 0;
2192                                 continue;
2193                         }
2194                         device->handler = handler;
2195                         ret = handler->attach(device, devid);
2196                         if (ret > 0)
2197                                 break;
2198
2199                         device->handler = NULL;
2200                         if (ret < 0)
2201                                 break;
2202                 }
2203         }
2204
2205         return ret;
2206 }
2207
2208 static int acpi_bus_attach(struct acpi_device *device, void *first_pass)
2209 {
2210         bool skip = !first_pass && device->flags.visited;
2211         acpi_handle ejd;
2212         int ret;
2213
2214         if (skip)
2215                 goto ok;
2216
2217         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2218                 register_dock_dependent_device(device, ejd);
2219
2220         acpi_bus_get_status(device);
2221         /* Skip devices that are not ready for enumeration (e.g. not present) */
2222         if (!acpi_dev_ready_for_enumeration(device)) {
2223                 device->flags.initialized = false;
2224                 acpi_device_clear_enumerated(device);
2225                 device->flags.power_manageable = 0;
2226                 return 0;
2227         }
2228         if (device->handler)
2229                 goto ok;
2230
2231         if (!device->flags.initialized) {
2232                 device->flags.power_manageable =
2233                         device->power.states[ACPI_STATE_D0].flags.valid;
2234                 if (acpi_bus_init_power(device))
2235                         device->flags.power_manageable = 0;
2236
2237                 device->flags.initialized = true;
2238         } else if (device->flags.visited) {
2239                 goto ok;
2240         }
2241
2242         ret = acpi_scan_attach_handler(device);
2243         if (ret < 0)
2244                 return 0;
2245
2246         device->flags.match_driver = true;
2247         if (ret > 0 && !device->flags.enumeration_by_parent) {
2248                 acpi_device_set_enumerated(device);
2249                 goto ok;
2250         }
2251
2252         ret = device_attach(&device->dev);
2253         if (ret < 0)
2254                 return 0;
2255
2256         if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2257                 acpi_default_enumeration(device);
2258         else
2259                 acpi_device_set_enumerated(device);
2260
2261 ok:
2262         acpi_dev_for_each_child(device, acpi_bus_attach, first_pass);
2263
2264         if (!skip && device->handler && device->handler->hotplug.notify_online)
2265                 device->handler->hotplug.notify_online(device);
2266
2267         return 0;
2268 }
2269
2270 static int acpi_dev_get_next_consumer_dev_cb(struct acpi_dep_data *dep, void *data)
2271 {
2272         struct acpi_device **adev_p = data;
2273         struct acpi_device *adev = *adev_p;
2274
2275         /*
2276          * If we're passed a 'previous' consumer device then we need to skip
2277          * any consumers until we meet the previous one, and then NULL @data
2278          * so the next one can be returned.
2279          */
2280         if (adev) {
2281                 if (dep->consumer == adev->handle)
2282                         *adev_p = NULL;
2283
2284                 return 0;
2285         }
2286
2287         adev = acpi_get_acpi_dev(dep->consumer);
2288         if (adev) {
2289                 *(struct acpi_device **)data = adev;
2290                 return 1;
2291         }
2292         /* Continue parsing if the device object is not present. */
2293         return 0;
2294 }
2295
2296 struct acpi_scan_clear_dep_work {
2297         struct work_struct work;
2298         struct acpi_device *adev;
2299 };
2300
2301 static void acpi_scan_clear_dep_fn(struct work_struct *work)
2302 {
2303         struct acpi_scan_clear_dep_work *cdw;
2304
2305         cdw = container_of(work, struct acpi_scan_clear_dep_work, work);
2306
2307         acpi_scan_lock_acquire();
2308         acpi_bus_attach(cdw->adev, (void *)true);
2309         acpi_scan_lock_release();
2310
2311         acpi_dev_put(cdw->adev);
2312         kfree(cdw);
2313 }
2314
2315 static bool acpi_scan_clear_dep_queue(struct acpi_device *adev)
2316 {
2317         struct acpi_scan_clear_dep_work *cdw;
2318
2319         if (adev->dep_unmet)
2320                 return false;
2321
2322         cdw = kmalloc(sizeof(*cdw), GFP_KERNEL);
2323         if (!cdw)
2324                 return false;
2325
2326         cdw->adev = adev;
2327         INIT_WORK(&cdw->work, acpi_scan_clear_dep_fn);
2328         /*
2329          * Since the work function may block on the lock until the entire
2330          * initial enumeration of devices is complete, put it into the unbound
2331          * workqueue.
2332          */
2333         queue_work(system_unbound_wq, &cdw->work);
2334
2335         return true;
2336 }
2337
2338 static void acpi_scan_delete_dep_data(struct acpi_dep_data *dep)
2339 {
2340         list_del(&dep->node);
2341         kfree(dep);
2342 }
2343
2344 static int acpi_scan_clear_dep(struct acpi_dep_data *dep, void *data)
2345 {
2346         struct acpi_device *adev = acpi_get_acpi_dev(dep->consumer);
2347
2348         if (adev) {
2349                 adev->dep_unmet--;
2350                 if (!acpi_scan_clear_dep_queue(adev))
2351                         acpi_dev_put(adev);
2352         }
2353
2354         if (dep->free_when_met)
2355                 acpi_scan_delete_dep_data(dep);
2356         else
2357                 dep->met = true;
2358
2359         return 0;
2360 }
2361
2362 /**
2363  * acpi_walk_dep_device_list - Apply a callback to every entry in acpi_dep_list
2364  * @handle:     The ACPI handle of the supplier device
2365  * @callback:   Pointer to the callback function to apply
2366  * @data:       Pointer to some data to pass to the callback
2367  *
2368  * The return value of the callback determines this function's behaviour. If 0
2369  * is returned we continue to iterate over acpi_dep_list. If a positive value
2370  * is returned then the loop is broken but this function returns 0. If a
2371  * negative value is returned by the callback then the loop is broken and that
2372  * value is returned as the final error.
2373  */
2374 static int acpi_walk_dep_device_list(acpi_handle handle,
2375                                 int (*callback)(struct acpi_dep_data *, void *),
2376                                 void *data)
2377 {
2378         struct acpi_dep_data *dep, *tmp;
2379         int ret = 0;
2380
2381         mutex_lock(&acpi_dep_list_lock);
2382         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2383                 if (dep->supplier == handle) {
2384                         ret = callback(dep, data);
2385                         if (ret)
2386                                 break;
2387                 }
2388         }
2389         mutex_unlock(&acpi_dep_list_lock);
2390
2391         return ret > 0 ? 0 : ret;
2392 }
2393
2394 /**
2395  * acpi_dev_clear_dependencies - Inform consumers that the device is now active
2396  * @supplier: Pointer to the supplier &struct acpi_device
2397  *
2398  * Clear dependencies on the given device.
2399  */
2400 void acpi_dev_clear_dependencies(struct acpi_device *supplier)
2401 {
2402         acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
2403 }
2404 EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies);
2405
2406 /**
2407  * acpi_dev_ready_for_enumeration - Check if the ACPI device is ready for enumeration
2408  * @device: Pointer to the &struct acpi_device to check
2409  *
2410  * Check if the device is present and has no unmet dependencies.
2411  *
2412  * Return true if the device is ready for enumeratino. Otherwise, return false.
2413  */
2414 bool acpi_dev_ready_for_enumeration(const struct acpi_device *device)
2415 {
2416         if (device->flags.honor_deps && device->dep_unmet)
2417                 return false;
2418
2419         return acpi_device_is_present(device);
2420 }
2421 EXPORT_SYMBOL_GPL(acpi_dev_ready_for_enumeration);
2422
2423 /**
2424  * acpi_dev_get_next_consumer_dev - Return the next adev dependent on @supplier
2425  * @supplier: Pointer to the dependee device
2426  * @start: Pointer to the current dependent device
2427  *
2428  * Returns the next &struct acpi_device which declares itself dependent on
2429  * @supplier via the _DEP buffer, parsed from the acpi_dep_list.
2430  *
2431  * If the returned adev is not passed as @start to this function, the caller is
2432  * responsible for putting the reference to adev when it is no longer needed.
2433  */
2434 struct acpi_device *acpi_dev_get_next_consumer_dev(struct acpi_device *supplier,
2435                                                    struct acpi_device *start)
2436 {
2437         struct acpi_device *adev = start;
2438
2439         acpi_walk_dep_device_list(supplier->handle,
2440                                   acpi_dev_get_next_consumer_dev_cb, &adev);
2441
2442         acpi_dev_put(start);
2443
2444         if (adev == start)
2445                 return NULL;
2446
2447         return adev;
2448 }
2449 EXPORT_SYMBOL_GPL(acpi_dev_get_next_consumer_dev);
2450
2451 static void acpi_scan_postponed_branch(acpi_handle handle)
2452 {
2453         struct acpi_device *adev = NULL;
2454
2455         if (ACPI_FAILURE(acpi_bus_check_add(handle, false, &adev)))
2456                 return;
2457
2458         acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2459                             acpi_bus_check_add_2, NULL, NULL, (void **)&adev);
2460
2461         /*
2462          * Populate the ACPI _CRS CSI-2 software nodes for the ACPI devices that
2463          * have been added above.
2464          */
2465         acpi_mipi_init_crs_csi2_swnodes();
2466
2467         acpi_bus_attach(adev, NULL);
2468 }
2469
2470 static void acpi_scan_postponed(void)
2471 {
2472         struct acpi_dep_data *dep, *tmp;
2473
2474         mutex_lock(&acpi_dep_list_lock);
2475
2476         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2477                 acpi_handle handle = dep->consumer;
2478
2479                 /*
2480                  * In case there are multiple acpi_dep_list entries with the
2481                  * same consumer, skip the current entry if the consumer device
2482                  * object corresponding to it is present already.
2483                  */
2484                 if (!acpi_fetch_acpi_dev(handle)) {
2485                         /*
2486                          * Even though the lock is released here, tmp is
2487                          * guaranteed to be valid, because none of the list
2488                          * entries following dep is marked as "free when met"
2489                          * and so they cannot be deleted.
2490                          */
2491                         mutex_unlock(&acpi_dep_list_lock);
2492
2493                         acpi_scan_postponed_branch(handle);
2494
2495                         mutex_lock(&acpi_dep_list_lock);
2496                 }
2497
2498                 if (dep->met)
2499                         acpi_scan_delete_dep_data(dep);
2500                 else
2501                         dep->free_when_met = true;
2502         }
2503
2504         mutex_unlock(&acpi_dep_list_lock);
2505 }
2506
2507 /**
2508  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2509  * @handle: Root of the namespace scope to scan.
2510  *
2511  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2512  * found devices.
2513  *
2514  * If no devices were found, -ENODEV is returned, but it does not mean that
2515  * there has been a real error.  There just have been no suitable ACPI objects
2516  * in the table trunk from which the kernel could create a device and add an
2517  * appropriate driver.
2518  *
2519  * Must be called under acpi_scan_lock.
2520  */
2521 int acpi_bus_scan(acpi_handle handle)
2522 {
2523         struct acpi_device *device = NULL;
2524
2525         /* Pass 1: Avoid enumerating devices with missing dependencies. */
2526
2527         if (ACPI_SUCCESS(acpi_bus_check_add(handle, true, &device)))
2528                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2529                                     acpi_bus_check_add_1, NULL, NULL,
2530                                     (void **)&device);
2531
2532         if (!device)
2533                 return -ENODEV;
2534
2535         /*
2536          * Set up ACPI _CRS CSI-2 software nodes using information extracted
2537          * from the _CRS CSI-2 resource descriptors during the ACPI namespace
2538          * walk above and MIPI DisCo for Imaging device properties.
2539          */
2540         acpi_mipi_scan_crs_csi2();
2541         acpi_mipi_init_crs_csi2_swnodes();
2542
2543         acpi_bus_attach(device, (void *)true);
2544
2545         /* Pass 2: Enumerate all of the remaining devices. */
2546
2547         acpi_scan_postponed();
2548
2549         acpi_mipi_crs_csi2_cleanup();
2550
2551         return 0;
2552 }
2553 EXPORT_SYMBOL(acpi_bus_scan);
2554
2555 static int acpi_bus_trim_one(struct acpi_device *adev, void *not_used)
2556 {
2557         struct acpi_scan_handler *handler = adev->handler;
2558
2559         acpi_dev_for_each_child_reverse(adev, acpi_bus_trim_one, NULL);
2560
2561         adev->flags.match_driver = false;
2562         if (handler) {
2563                 if (handler->detach)
2564                         handler->detach(adev);
2565
2566                 adev->handler = NULL;
2567         } else {
2568                 device_release_driver(&adev->dev);
2569         }
2570         /*
2571          * Most likely, the device is going away, so put it into D3cold before
2572          * that.
2573          */
2574         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2575         adev->flags.initialized = false;
2576         acpi_device_clear_enumerated(adev);
2577
2578         return 0;
2579 }
2580
2581 /**
2582  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2583  * @adev: Root of the ACPI namespace scope to walk.
2584  *
2585  * Must be called under acpi_scan_lock.
2586  */
2587 void acpi_bus_trim(struct acpi_device *adev)
2588 {
2589         acpi_bus_trim_one(adev, NULL);
2590 }
2591 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2592
2593 int acpi_bus_register_early_device(int type)
2594 {
2595         struct acpi_device *device = NULL;
2596         int result;
2597
2598         result = acpi_add_single_object(&device, NULL, type, false);
2599         if (result)
2600                 return result;
2601
2602         device->flags.match_driver = true;
2603         return device_attach(&device->dev);
2604 }
2605 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2606
2607 static void acpi_bus_scan_fixed(void)
2608 {
2609         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2610                 struct acpi_device *adev = NULL;
2611
2612                 acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_POWER_BUTTON,
2613                                        false);
2614                 if (adev) {
2615                         adev->flags.match_driver = true;
2616                         if (device_attach(&adev->dev) >= 0)
2617                                 device_init_wakeup(&adev->dev, true);
2618                         else
2619                                 dev_dbg(&adev->dev, "No driver\n");
2620                 }
2621         }
2622
2623         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2624                 struct acpi_device *adev = NULL;
2625
2626                 acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_SLEEP_BUTTON,
2627                                        false);
2628                 if (adev) {
2629                         adev->flags.match_driver = true;
2630                         if (device_attach(&adev->dev) < 0)
2631                                 dev_dbg(&adev->dev, "No driver\n");
2632                 }
2633         }
2634 }
2635
2636 static void __init acpi_get_spcr_uart_addr(void)
2637 {
2638         acpi_status status;
2639         struct acpi_table_spcr *spcr_ptr;
2640
2641         status = acpi_get_table(ACPI_SIG_SPCR, 0,
2642                                 (struct acpi_table_header **)&spcr_ptr);
2643         if (ACPI_FAILURE(status)) {
2644                 pr_warn("STAO table present, but SPCR is missing\n");
2645                 return;
2646         }
2647
2648         spcr_uart_addr = spcr_ptr->serial_port.address;
2649         acpi_put_table((struct acpi_table_header *)spcr_ptr);
2650 }
2651
2652 static bool acpi_scan_initialized;
2653
2654 void __init acpi_scan_init(void)
2655 {
2656         acpi_status status;
2657         struct acpi_table_stao *stao_ptr;
2658
2659         acpi_pci_root_init();
2660         acpi_pci_link_init();
2661         acpi_processor_init();
2662         acpi_platform_init();
2663         acpi_lpss_init();
2664         acpi_apd_init();
2665         acpi_cmos_rtc_init();
2666         acpi_container_init();
2667         acpi_memory_hotplug_init();
2668         acpi_watchdog_init();
2669         acpi_pnp_init();
2670         acpi_int340x_thermal_init();
2671         acpi_init_lpit();
2672
2673         acpi_scan_add_handler(&generic_device_handler);
2674
2675         /*
2676          * If there is STAO table, check whether it needs to ignore the UART
2677          * device in SPCR table.
2678          */
2679         status = acpi_get_table(ACPI_SIG_STAO, 0,
2680                                 (struct acpi_table_header **)&stao_ptr);
2681         if (ACPI_SUCCESS(status)) {
2682                 if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2683                         pr_info("STAO Name List not yet supported.\n");
2684
2685                 if (stao_ptr->ignore_uart)
2686                         acpi_get_spcr_uart_addr();
2687
2688                 acpi_put_table((struct acpi_table_header *)stao_ptr);
2689         }
2690
2691         acpi_gpe_apply_masked_gpes();
2692         acpi_update_all_gpes();
2693
2694         /*
2695          * Although we call __add_memory() that is documented to require the
2696          * device_hotplug_lock, it is not necessary here because this is an
2697          * early code when userspace or any other code path cannot trigger
2698          * hotplug/hotunplug operations.
2699          */
2700         mutex_lock(&acpi_scan_lock);
2701         /*
2702          * Enumerate devices in the ACPI namespace.
2703          */
2704         if (acpi_bus_scan(ACPI_ROOT_OBJECT))
2705                 goto unlock;
2706
2707         acpi_root = acpi_fetch_acpi_dev(ACPI_ROOT_OBJECT);
2708         if (!acpi_root)
2709                 goto unlock;
2710
2711         /* Fixed feature devices do not exist on HW-reduced platform */
2712         if (!acpi_gbl_reduced_hardware)
2713                 acpi_bus_scan_fixed();
2714
2715         acpi_turn_off_unused_power_resources();
2716
2717         acpi_scan_initialized = true;
2718
2719 unlock:
2720         mutex_unlock(&acpi_scan_lock);
2721 }
2722
2723 static struct acpi_probe_entry *ape;
2724 static int acpi_probe_count;
2725 static DEFINE_MUTEX(acpi_probe_mutex);
2726
2727 static int __init acpi_match_madt(union acpi_subtable_headers *header,
2728                                   const unsigned long end)
2729 {
2730         if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2731                 if (!ape->probe_subtbl(header, end))
2732                         acpi_probe_count++;
2733
2734         return 0;
2735 }
2736
2737 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2738 {
2739         int count = 0;
2740
2741         if (acpi_disabled)
2742                 return 0;
2743
2744         mutex_lock(&acpi_probe_mutex);
2745         for (ape = ap_head; nr; ape++, nr--) {
2746                 if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2747                         acpi_probe_count = 0;
2748                         acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2749                         count += acpi_probe_count;
2750                 } else {
2751                         int res;
2752                         res = acpi_table_parse(ape->id, ape->probe_table);
2753                         if (!res)
2754                                 count++;
2755                 }
2756         }
2757         mutex_unlock(&acpi_probe_mutex);
2758
2759         return count;
2760 }
2761
2762 static void acpi_table_events_fn(struct work_struct *work)
2763 {
2764         acpi_scan_lock_acquire();
2765         acpi_bus_scan(ACPI_ROOT_OBJECT);
2766         acpi_scan_lock_release();
2767
2768         kfree(work);
2769 }
2770
2771 void acpi_scan_table_notify(void)
2772 {
2773         struct work_struct *work;
2774
2775         if (!acpi_scan_initialized)
2776                 return;
2777
2778         work = kmalloc(sizeof(*work), GFP_KERNEL);
2779         if (!work)
2780                 return;
2781
2782         INIT_WORK(work, acpi_table_events_fn);
2783         schedule_work(work);
2784 }
2785
2786 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2787 {
2788         return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2789 }
2790 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2791
2792 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2793 {
2794         return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2795 }
2796 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);