drivers/video/fbdev/core/fbmem.c

   1 /*
   2  *  linux/drivers/video/fbmem.c
   3  *
   4  *  Copyright (C) 1994 Martin Schaller
   5  *
   6  *      2001 - Documented with DocBook
   7  *      - Brad Douglas <brad@neruo.com>
   8  *
   9  * This file is subject to the terms and conditions of the GNU General Public
  10  * License.  See the file COPYING in the main directory of this archive
  11  * for more details.
  12  */
  13
  14 #include <linux/console.h>
  15 #include <linux/export.h>
  16 #include <linux/fb.h>
  17 #include <linux/fbcon.h>
  18
  19 #include <video/nomodeset.h>
  20
  21 #include "fb_internal.h"
  22
  23     /*
  24      *  Frame buffer device initialization and setup routines
  25      */
  26
  27 #define FBPIXMAPSIZE    (1024 * 8)
  28
  29 struct class *fb_class;
  30
  31 DEFINE_MUTEX(registration_lock);
  32 struct fb_info *registered_fb[FB_MAX] __read_mostly;
  33 int num_registered_fb __read_mostly;
  34 #define for_each_registered_fb(i)               \
  35         for (i = 0; i < FB_MAX; i++)            \
  36                 if (!registered_fb[i]) {} else
  37
  38 struct fb_info *get_fb_info(unsigned int idx)
  39 {
  40         struct fb_info *fb_info;
  41
  42         if (idx >= FB_MAX)
  43                 return ERR_PTR(-ENODEV);
  44
  45         mutex_lock(&registration_lock);
  46         fb_info = registered_fb[idx];
  47         if (fb_info)
  48                 refcount_inc(&fb_info->count);
  49         mutex_unlock(&registration_lock);
  50
  51         return fb_info;
  52 }
  53
  54 void put_fb_info(struct fb_info *fb_info)
  55 {
  56         if (!refcount_dec_and_test(&fb_info->count))
  57                 return;
  58         if (fb_info->fbops->fb_destroy)
  59                 fb_info->fbops->fb_destroy(fb_info);
  60 }
  61
  62 /*
  63  * Helpers
  64  */
  65
  66 int fb_get_color_depth(struct fb_var_screeninfo *var,
  67                        struct fb_fix_screeninfo *fix)
  68 {
  69         int depth = 0;
  70
  71         if (fix->visual == FB_VISUAL_MONO01 ||
  72             fix->visual == FB_VISUAL_MONO10)
  73                 depth = 1;
  74         else {
  75                 if (var->green.length == var->blue.length &&
  76                     var->green.length == var->red.length &&
  77                     var->green.offset == var->blue.offset &&
  78                     var->green.offset == var->red.offset)
  79                         depth = var->green.length;
  80                 else
  81                         depth = var->green.length + var->red.length +
  82                                 var->blue.length;
  83         }
  84
  85         return depth;
  86 }
  87 EXPORT_SYMBOL(fb_get_color_depth);
  88
  89 /*
  90  * Data padding functions.
  91  */
  92 void fb_pad_aligned_buffer(u8 *dst, u32 d_pitch, u8 *src, u32 s_pitch, u32 height)
  93 {
  94         __fb_pad_aligned_buffer(dst, d_pitch, src, s_pitch, height);
  95 }
  96 EXPORT_SYMBOL(fb_pad_aligned_buffer);
  97
  98 void fb_pad_unaligned_buffer(u8 *dst, u32 d_pitch, u8 *src, u32 idx, u32 height,
  99                                 u32 shift_high, u32 shift_low, u32 mod)
 100 {
 101         u8 mask = (u8) (0xfff << shift_high), tmp;
 102         int i, j;
 103
 104         for (i = height; i--; ) {
 105                 for (j = 0; j < idx; j++) {
 106                         tmp = dst[j];
 107                         tmp &= mask;
 108                         tmp |= *src >> shift_low;
 109                         dst[j] = tmp;
 110                         tmp = *src << shift_high;
 111                         dst[j+1] = tmp;
 112                         src++;
 113                 }
 114                 tmp = dst[idx];
 115                 tmp &= mask;
 116                 tmp |= *src >> shift_low;
 117                 dst[idx] = tmp;
 118                 if (shift_high < mod) {
 119                         tmp = *src << shift_high;
 120                         dst[idx+1] = tmp;
 121                 }
 122                 src++;
 123                 dst += d_pitch;
 124         }
 125 }
 126 EXPORT_SYMBOL(fb_pad_unaligned_buffer);
 127
 128 /*
 129  * we need to lock this section since fb_cursor
 130  * may use fb_imageblit()
 131  */
 132 char* fb_get_buffer_offset(struct fb_info *info, struct fb_pixmap *buf, u32 size)
 133 {
 134         u32 align = buf->buf_align - 1, offset;
 135         char *addr = buf->addr;
 136
 137         /* If IO mapped, we need to sync before access, no sharing of
 138          * the pixmap is done
 139          */
 140         if (buf->flags & FB_PIXMAP_IO) {
 141                 if (info->fbops->fb_sync && (buf->flags & FB_PIXMAP_SYNC))
 142                         info->fbops->fb_sync(info);
 143                 return addr;
 144         }
 145
 146         /* See if we fit in the remaining pixmap space */
 147         offset = buf->offset + align;
 148         offset &= ~align;
 149         if (offset + size > buf->size) {
 150                 /* We do not fit. In order to be able to re-use the buffer,
 151                  * we must ensure no asynchronous DMA'ing or whatever operation
 152                  * is in progress, we sync for that.
 153                  */
 154                 if (info->fbops->fb_sync && (buf->flags & FB_PIXMAP_SYNC))
 155                         info->fbops->fb_sync(info);
 156                 offset = 0;
 157         }
 158         buf->offset = offset + size;
 159         addr += offset;
 160
 161         return addr;
 162 }
 163 EXPORT_SYMBOL(fb_get_buffer_offset);
 164
 165 int
 166 fb_pan_display(struct fb_info *info, struct fb_var_screeninfo *var)
 167 {
 168         struct fb_fix_screeninfo *fix = &info->fix;
 169         unsigned int yres = info->var.yres;
 170         int err = 0;
 171
 172         if (var->yoffset > 0) {
 173                 if (var->vmode & FB_VMODE_YWRAP) {
 174                         if (!fix->ywrapstep || (var->yoffset % fix->ywrapstep))
 175                                 err = -EINVAL;
 176                         else
 177                                 yres = 0;
 178                 } else if (!fix->ypanstep || (var->yoffset % fix->ypanstep))
 179                         err = -EINVAL;
 180         }
 181
 182         if (var->xoffset > 0 && (!fix->xpanstep ||
 183                                  (var->xoffset % fix->xpanstep)))
 184                 err = -EINVAL;
 185
 186         if (err || !info->fbops->fb_pan_display ||
 187             var->yoffset > info->var.yres_virtual - yres ||
 188             var->xoffset > info->var.xres_virtual - info->var.xres)
 189                 return -EINVAL;
 190
 191         if ((err = info->fbops->fb_pan_display(var, info)))
 192                 return err;
 193         info->var.xoffset = var->xoffset;
 194         info->var.yoffset = var->yoffset;
 195         if (var->vmode & FB_VMODE_YWRAP)
 196                 info->var.vmode |= FB_VMODE_YWRAP;
 197         else
 198                 info->var.vmode &= ~FB_VMODE_YWRAP;
 199         return 0;
 200 }
 201 EXPORT_SYMBOL(fb_pan_display);
 202
 203 static int fb_check_caps(struct fb_info *info, struct fb_var_screeninfo *var,
 204                          u32 activate)
 205 {
 206         struct fb_blit_caps caps, fbcaps;
 207         int err = 0;
 208
 209         memset(&caps, 0, sizeof(caps));
 210         memset(&fbcaps, 0, sizeof(fbcaps));
 211         caps.flags = (activate & FB_ACTIVATE_ALL) ? 1 : 0;
 212         fbcon_get_requirement(info, &caps);
 213         info->fbops->fb_get_caps(info, &fbcaps, var);
 214
 215         if (!bitmap_subset(caps.x, fbcaps.x, FB_MAX_BLIT_WIDTH) ||
 216             !bitmap_subset(caps.y, fbcaps.y, FB_MAX_BLIT_HEIGHT) ||
 217             (fbcaps.len < caps.len))
 218                 err = -EINVAL;
 219
 220         return err;
 221 }
 222
 223 int
 224 fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
 225 {
 226         int ret = 0;
 227         u32 activate;
 228         struct fb_var_screeninfo old_var;
 229         struct fb_videomode mode;
 230         struct fb_event event;
 231         u32 unused;
 232
 233         if (var->activate & FB_ACTIVATE_INV_MODE) {
 234                 struct fb_videomode mode1, mode2;
 235
 236                 fb_var_to_videomode(&mode1, var);
 237                 fb_var_to_videomode(&mode2, &info->var);
 238                 /* make sure we don't delete the videomode of current var */
 239                 ret = fb_mode_is_equal(&mode1, &mode2);
 240                 if (!ret) {
 241                         ret = fbcon_mode_deleted(info, &mode1);
 242                         if (!ret)
 243                                 fb_delete_videomode(&mode1, &info->modelist);
 244                 }
 245
 246                 return ret ? -EINVAL : 0;
 247         }
 248
 249         if (!(var->activate & FB_ACTIVATE_FORCE) &&
 250             !memcmp(&info->var, var, sizeof(struct fb_var_screeninfo)))
 251                 return 0;
 252
 253         activate = var->activate;
 254
 255         /* When using FOURCC mode, make sure the red, green, blue and
 256          * transp fields are set to 0.
 257          */
 258         if ((info->fix.capabilities & FB_CAP_FOURCC) &&
 259             var->grayscale > 1) {
 260                 if (var->red.offset     || var->green.offset    ||
 261                     var->blue.offset    || var->transp.offset   ||
 262                     var->red.length     || var->green.length    ||
 263                     var->blue.length    || var->transp.length   ||
 264                     var->red.msb_right  || var->green.msb_right ||
 265                     var->blue.msb_right || var->transp.msb_right)
 266                         return -EINVAL;
 267         }
 268
 269         if (!info->fbops->fb_check_var) {
 270                 *var = info->var;
 271                 return 0;
 272         }
 273
 274         /* bitfill_aligned() assumes that it's at least 8x8 */
 275         if (var->xres < 8 || var->yres < 8)
 276                 return -EINVAL;
 277
 278         /* Too huge resolution causes multiplication overflow. */
 279         if (check_mul_overflow(var->xres, var->yres, &unused) ||
 280             check_mul_overflow(var->xres_virtual, var->yres_virtual, &unused))
 281                 return -EINVAL;
 282
 283         ret = info->fbops->fb_check_var(var, info);
 284
 285         if (ret)
 286                 return ret;
 287
 288         /* verify that virtual resolution >= physical resolution */
 289         if (var->xres_virtual < var->xres ||
 290             var->yres_virtual < var->yres) {
 291                 pr_warn("WARNING: fbcon: Driver '%s' missed to adjust virtual screen size (%ux%u vs. %ux%u)\n",
 292                         info->fix.id,
 293                         var->xres_virtual, var->yres_virtual,
 294                         var->xres, var->yres);
 295                 return -EINVAL;
 296         }
 297
 298         if ((var->activate & FB_ACTIVATE_MASK) != FB_ACTIVATE_NOW)
 299                 return 0;
 300
 301         if (info->fbops->fb_get_caps) {
 302                 ret = fb_check_caps(info, var, activate);
 303
 304                 if (ret)
 305                         return ret;
 306         }
 307
 308         old_var = info->var;
 309         info->var = *var;
 310
 311         if (info->fbops->fb_set_par) {
 312                 ret = info->fbops->fb_set_par(info);
 313
 314                 if (ret) {
 315                         info->var = old_var;
 316                         printk(KERN_WARNING "detected "
 317                                 "fb_set_par error, "
 318                                 "error code: %d\n", ret);
 319                         return ret;
 320                 }
 321         }
 322
 323         fb_pan_display(info, &info->var);
 324         fb_set_cmap(&info->cmap, info);
 325         fb_var_to_videomode(&mode, &info->var);
 326
 327         if (info->modelist.prev && info->modelist.next &&
 328             !list_empty(&info->modelist))
 329                 ret = fb_add_videomode(&mode, &info->modelist);
 330
 331         if (ret)
 332                 return ret;
 333
 334         event.info = info;
 335         event.data = &mode;
 336         fb_notifier_call_chain(FB_EVENT_MODE_CHANGE, &event);
 337
 338         return 0;
 339 }
 340 EXPORT_SYMBOL(fb_set_var);
 341
 342 int
 343 fb_blank(struct fb_info *info, int blank)
 344 {
 345         struct fb_event event;
 346         int ret = -EINVAL;
 347
 348         if (blank > FB_BLANK_POWERDOWN)
 349                 blank = FB_BLANK_POWERDOWN;
 350
 351         event.info = info;
 352         event.data = &blank;
 353
 354         if (info->fbops->fb_blank)
 355                 ret = info->fbops->fb_blank(blank, info);
 356
 357         if (!ret)
 358                 fb_notifier_call_chain(FB_EVENT_BLANK, &event);
 359
 360         return ret;
 361 }
 362 EXPORT_SYMBOL(fb_blank);
 363
 364 static int fb_check_foreignness(struct fb_info *fi)
 365 {
 366         const bool foreign_endian = fi->flags & FBINFO_FOREIGN_ENDIAN;
 367
 368         fi->flags &= ~FBINFO_FOREIGN_ENDIAN;
 369
 370 #ifdef __BIG_ENDIAN
 371         fi->flags |= foreign_endian ? 0 : FBINFO_BE_MATH;
 372 #else
 373         fi->flags |= foreign_endian ? FBINFO_BE_MATH : 0;
 374 #endif /* __BIG_ENDIAN */
 375
 376         if (fi->flags & FBINFO_BE_MATH && !fb_be_math(fi)) {
 377                 pr_err("%s: enable CONFIG_FB_BIG_ENDIAN to "
 378                        "support this framebuffer\n", fi->fix.id);
 379                 return -ENOSYS;
 380         } else if (!(fi->flags & FBINFO_BE_MATH) && fb_be_math(fi)) {
 381                 pr_err("%s: enable CONFIG_FB_LITTLE_ENDIAN to "
 382                        "support this framebuffer\n", fi->fix.id);
 383                 return -ENOSYS;
 384         }
 385
 386         return 0;
 387 }
 388
 389 static int do_register_framebuffer(struct fb_info *fb_info)
 390 {
 391         int i;
 392         struct fb_videomode mode;
 393
 394         if (fb_check_foreignness(fb_info))
 395                 return -ENOSYS;
 396
 397         if (num_registered_fb == FB_MAX)
 398                 return -ENXIO;
 399
 400         num_registered_fb++;
 401         for (i = 0 ; i < FB_MAX; i++)
 402                 if (!registered_fb[i])
 403                         break;
 404         fb_info->node = i;
 405         refcount_set(&fb_info->count, 1);
 406         mutex_init(&fb_info->lock);
 407         mutex_init(&fb_info->mm_lock);
 408
 409         fb_device_create(fb_info);
 410
 411         if (fb_info->pixmap.addr == NULL) {
 412                 fb_info->pixmap.addr = kmalloc(FBPIXMAPSIZE, GFP_KERNEL);
 413                 if (fb_info->pixmap.addr) {
 414                         fb_info->pixmap.size = FBPIXMAPSIZE;
 415                         fb_info->pixmap.buf_align = 1;
 416                         fb_info->pixmap.scan_align = 1;
 417                         fb_info->pixmap.access_align = 32;
 418                         fb_info->pixmap.flags = FB_PIXMAP_DEFAULT;
 419                 }
 420         }
 421         fb_info->pixmap.offset = 0;
 422
 423         if (bitmap_empty(fb_info->pixmap.blit_x, FB_MAX_BLIT_WIDTH))
 424                 bitmap_fill(fb_info->pixmap.blit_x, FB_MAX_BLIT_WIDTH);
 425
 426         if (bitmap_empty(fb_info->pixmap.blit_y, FB_MAX_BLIT_HEIGHT))
 427                 bitmap_fill(fb_info->pixmap.blit_y, FB_MAX_BLIT_HEIGHT);
 428
 429         if (!fb_info->modelist.prev || !fb_info->modelist.next)
 430                 INIT_LIST_HEAD(&fb_info->modelist);
 431
 432         if (fb_info->skip_vt_switch)
 433                 pm_vt_switch_required(fb_info->device, false);
 434         else
 435                 pm_vt_switch_required(fb_info->device, true);
 436
 437         fb_var_to_videomode(&mode, &fb_info->var);
 438         fb_add_videomode(&mode, &fb_info->modelist);
 439         registered_fb[i] = fb_info;
 440
 441 #ifdef CONFIG_GUMSTIX_AM200EPD
 442         {
 443                 struct fb_event event;
 444                 event.info = fb_info;
 445                 fb_notifier_call_chain(FB_EVENT_FB_REGISTERED, &event);
 446         }
 447 #endif
 448
 449         return fbcon_fb_registered(fb_info);
 450 }
 451
 452 static void unbind_console(struct fb_info *fb_info)
 453 {
 454         int i = fb_info->node;
 455
 456         if (WARN_ON(i < 0 || i >= FB_MAX || registered_fb[i] != fb_info))
 457                 return;
 458
 459         fbcon_fb_unbind(fb_info);
 460 }
 461
 462 static void unlink_framebuffer(struct fb_info *fb_info)
 463 {
 464         int i;
 465
 466         i = fb_info->node;
 467         if (WARN_ON(i < 0 || i >= FB_MAX || registered_fb[i] != fb_info))
 468                 return;
 469
 470         fb_device_destroy(fb_info);
 471         pm_vt_switch_unregister(fb_info->device);
 472         unbind_console(fb_info);
 473 }
 474
 475 static void do_unregister_framebuffer(struct fb_info *fb_info)
 476 {
 477         unlink_framebuffer(fb_info);
 478         if (fb_info->pixmap.addr &&
 479             (fb_info->pixmap.flags & FB_PIXMAP_DEFAULT)) {
 480                 kfree(fb_info->pixmap.addr);
 481                 fb_info->pixmap.addr = NULL;
 482         }
 483
 484         fb_destroy_modelist(&fb_info->modelist);
 485         registered_fb[fb_info->node] = NULL;
 486         num_registered_fb--;
 487 #ifdef CONFIG_GUMSTIX_AM200EPD
 488         {
 489                 struct fb_event event;
 490                 event.info = fb_info;
 491                 fb_notifier_call_chain(FB_EVENT_FB_UNREGISTERED, &event);
 492         }
 493 #endif
 494         fbcon_fb_unregistered(fb_info);
 495
 496         /* this may free fb info */
 497         put_fb_info(fb_info);
 498 }
 499
 500 /**
 501  *      register_framebuffer - registers a frame buffer device
 502  *      @fb_info: frame buffer info structure
 503  *
 504  *      Registers a frame buffer device @fb_info.
 505  *
 506  *      Returns negative errno on error, or zero for success.
 507  *
 508  */
 509 int
 510 register_framebuffer(struct fb_info *fb_info)
 511 {
 512         int ret;
 513
 514         mutex_lock(&registration_lock);
 515         ret = do_register_framebuffer(fb_info);
 516         mutex_unlock(&registration_lock);
 517
 518         return ret;
 519 }
 520 EXPORT_SYMBOL(register_framebuffer);
 521
 522 /**
 523  *      unregister_framebuffer - releases a frame buffer device
 524  *      @fb_info: frame buffer info structure
 525  *
 526  *      Unregisters a frame buffer device @fb_info.
 527  *
 528  *      Returns negative errno on error, or zero for success.
 529  *
 530  *      This function will also notify the framebuffer console
 531  *      to release the driver.
 532  *
 533  *      This is meant to be called within a driver's module_exit()
 534  *      function. If this is called outside module_exit(), ensure
 535  *      that the driver implements fb_open() and fb_release() to
 536  *      check that no processes are using the device.
 537  */
 538 void
 539 unregister_framebuffer(struct fb_info *fb_info)
 540 {
 541         mutex_lock(&registration_lock);
 542         do_unregister_framebuffer(fb_info);
 543         mutex_unlock(&registration_lock);
 544 }
 545 EXPORT_SYMBOL(unregister_framebuffer);
 546
 547 /**
 548  *      fb_set_suspend - low level driver signals suspend
 549  *      @info: framebuffer affected
 550  *      @state: 0 = resuming, !=0 = suspending
 551  *
 552  *      This is meant to be used by low level drivers to
 553  *      signal suspend/resume to the core & clients.
 554  *      It must be called with the console semaphore held
 555  */
 556 void fb_set_suspend(struct fb_info *info, int state)
 557 {
 558         WARN_CONSOLE_UNLOCKED();
 559
 560         if (state) {
 561                 fbcon_suspended(info);
 562                 info->state = FBINFO_STATE_SUSPENDED;
 563         } else {
 564                 info->state = FBINFO_STATE_RUNNING;
 565                 fbcon_resumed(info);
 566         }
 567 }
 568 EXPORT_SYMBOL(fb_set_suspend);
 569
 570 static int __init fbmem_init(void)
 571 {
 572         int ret;
 573
 574         fb_class = class_create("graphics");
 575         if (IS_ERR(fb_class)) {
 576                 ret = PTR_ERR(fb_class);
 577                 pr_err("Unable to create fb class; errno = %d\n", ret);
 578                 goto err_fb_class;
 579         }
 580
 581         ret = fb_init_procfs();
 582         if (ret)
 583                 goto err_class_destroy;
 584
 585         ret = fb_register_chrdev();
 586         if (ret)
 587                 goto err_fb_cleanup_procfs;
 588
 589         fb_console_init();
 590
 591         return 0;
 592
 593 err_fb_cleanup_procfs:
 594         fb_cleanup_procfs();
 595 err_class_destroy:
 596         class_destroy(fb_class);
 597 err_fb_class:
 598         fb_class = NULL;
 599         return ret;
 600 }
 601
 602 #ifdef MODULE
 603 static void __exit fbmem_exit(void)
 604 {
 605         fb_console_exit();
 606         fb_unregister_chrdev();
 607         fb_cleanup_procfs();
 608         class_destroy(fb_class);
 609 }
 610
 611 module_init(fbmem_init);
 612 module_exit(fbmem_exit);
 613 MODULE_LICENSE("GPL");
 614 MODULE_DESCRIPTION("Framebuffer base");
 615 #else
 616 subsys_initcall(fbmem_init);
 617 #endif
 618
 619 int fb_new_modelist(struct fb_info *info)
 620 {
 621         struct fb_var_screeninfo var = info->var;
 622         struct list_head *pos, *n;
 623         struct fb_modelist *modelist;
 624         struct fb_videomode *m, mode;
 625         int err;
 626
 627         list_for_each_safe(pos, n, &info->modelist) {
 628                 modelist = list_entry(pos, struct fb_modelist, list);
 629                 m = &modelist->mode;
 630                 fb_videomode_to_var(&var, m);
 631                 var.activate = FB_ACTIVATE_TEST;
 632                 err = fb_set_var(info, &var);
 633                 fb_var_to_videomode(&mode, &var);
 634                 if (err || !fb_mode_is_equal(m, &mode)) {
 635                         list_del(pos);
 636                         kfree(pos);
 637                 }
 638         }
 639
 640         if (list_empty(&info->modelist))
 641                 return 1;
 642
 643         fbcon_new_modelist(info);
 644
 645         return 0;
 646 }
 647
 648 bool fb_modesetting_disabled(const char *drvname)
 649 {
 650         bool fwonly = video_firmware_drivers_only();
 651
 652         if (fwonly)
 653                 pr_warn("Driver %s not loading because of nomodeset parameter\n",
 654                         drvname);
 655
 656         return fwonly;
 657 }
 658 EXPORT_SYMBOL(fb_modesetting_disabled);
 659
 660 MODULE_LICENSE("GPL");