drivers/video/fbsysfs.c

   1 /*
   2  * fbsysfs.c - framebuffer device class and attributes
   3  *
   4  * Copyright (c) 2004 James Simmons <jsimmons@infradead.org>
   5  *
   6  *      This program is free software you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  */
  11
  12 /*
  13  * Note:  currently there's only stubs for framebuffer_alloc and
  14  * framebuffer_release here.  The reson for that is that until all drivers
  15  * are converted to use it a sysfsification will open OOPSable races.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/fb.h>
  20 #include <linux/console.h>
  21 #include <linux/module.h>
  22
  23 #define FB_SYSFS_FLAG_ATTR 1
  24
  25 /**
  26  * framebuffer_alloc - creates a new frame buffer info structure
  27  *
  28  * @size: size of driver private data, can be zero
  29  * @dev: pointer to the device for this fb, this can be NULL
  30  *
  31  * Creates a new frame buffer info structure. Also reserves @size bytes
  32  * for driver private data (info->par). info->par (if any) will be
  33  * aligned to sizeof(long).
  34  *
  35  * Returns the new structure, or NULL if an error occured.
  36  *
  37  */
  38 struct fb_info *framebuffer_alloc(size_t size, struct device *dev)
  39 {
  40 #define BYTES_PER_LONG (BITS_PER_LONG/8)
  41 #define PADDING (BYTES_PER_LONG - (sizeof(struct fb_info) % BYTES_PER_LONG))
  42         int fb_info_size = sizeof(struct fb_info);
  43         struct fb_info *info;
  44         char *p;
  45
  46         if (size)
  47                 fb_info_size += PADDING;
  48
  49         p = kzalloc(fb_info_size + size, GFP_KERNEL);
  50
  51         if (!p)
  52                 return NULL;
  53
  54         info = (struct fb_info *) p;
  55
  56         if (size)
  57                 info->par = p + fb_info_size;
  58
  59         info->device = dev;
  60
  61 #ifdef CONFIG_FB_BACKLIGHT
  62         mutex_init(&info->bl_curve_mutex);
  63 #endif
  64
  65         return info;
  66 #undef PADDING
  67 #undef BYTES_PER_LONG
  68 }
  69 EXPORT_SYMBOL(framebuffer_alloc);
  70
  71 /**
  72  * framebuffer_release - marks the structure available for freeing
  73  *
  74  * @info: frame buffer info structure
  75  *
  76  * Drop the reference count of the device embedded in the
  77  * framebuffer info structure.
  78  *
  79  */
  80 void framebuffer_release(struct fb_info *info)
  81 {
  82         kfree(info);
  83 }
  84 EXPORT_SYMBOL(framebuffer_release);
  85
  86 static int activate(struct fb_info *fb_info, struct fb_var_screeninfo *var)
  87 {
  88         int err;
  89
  90         var->activate |= FB_ACTIVATE_FORCE;
  91         acquire_console_sem();
  92         fb_info->flags |= FBINFO_MISC_USEREVENT;
  93         err = fb_set_var(fb_info, var);
  94         fb_info->flags &= ~FBINFO_MISC_USEREVENT;
  95         release_console_sem();
  96         if (err)
  97                 return err;
  98         return 0;
  99 }
 100
 101 static int mode_string(char *buf, unsigned int offset,
 102                        const struct fb_videomode *mode)
 103 {
 104         char m = 'U';
 105         char v = 'p';
 106
 107         if (mode->flag & FB_MODE_IS_DETAILED)
 108                 m = 'D';
 109         if (mode->flag & FB_MODE_IS_VESA)
 110                 m = 'V';
 111         if (mode->flag & FB_MODE_IS_STANDARD)
 112                 m = 'S';
 113
 114         if (mode->vmode & FB_VMODE_INTERLACED)
 115                 v = 'i';
 116         if (mode->vmode & FB_VMODE_DOUBLE)
 117                 v = 'd';
 118
 119         return snprintf(&buf[offset], PAGE_SIZE - offset, "%c:%dx%d%c-%d\n",
 120                         m, mode->xres, mode->yres, v, mode->refresh);
 121 }
 122
 123 static ssize_t store_mode(struct device *device, struct device_attribute *attr,
 124                           const char *buf, size_t count)
 125 {
 126         struct fb_info *fb_info = dev_get_drvdata(device);
 127         char mstr[100];
 128         struct fb_var_screeninfo var;
 129         struct fb_modelist *modelist;
 130         struct fb_videomode *mode;
 131         struct list_head *pos;
 132         size_t i;
 133         int err;
 134
 135         memset(&var, 0, sizeof(var));
 136
 137         list_for_each(pos, &fb_info->modelist) {
 138                 modelist = list_entry(pos, struct fb_modelist, list);
 139                 mode = &modelist->mode;
 140                 i = mode_string(mstr, 0, mode);
 141                 if (strncmp(mstr, buf, max(count, i)) == 0) {
 142
 143                         var = fb_info->var;
 144                         fb_videomode_to_var(&var, mode);
 145                         if ((err = activate(fb_info, &var)))
 146                                 return err;
 147                         fb_info->mode = mode;
 148                         return count;
 149                 }
 150         }
 151         return -EINVAL;
 152 }
 153
 154 static ssize_t show_mode(struct device *device, struct device_attribute *attr,
 155                          char *buf)
 156 {
 157         struct fb_info *fb_info = dev_get_drvdata(device);
 158
 159         if (!fb_info->mode)
 160                 return 0;
 161
 162         return mode_string(buf, 0, fb_info->mode);
 163 }
 164
 165 static ssize_t store_modes(struct device *device,
 166                            struct device_attribute *attr,
 167                            const char *buf, size_t count)
 168 {
 169         struct fb_info *fb_info = dev_get_drvdata(device);
 170         LIST_HEAD(old_list);
 171         int i = count / sizeof(struct fb_videomode);
 172
 173         if (i * sizeof(struct fb_videomode) != count)
 174                 return -EINVAL;
 175
 176         acquire_console_sem();
 177         list_splice(&fb_info->modelist, &old_list);
 178         fb_videomode_to_modelist((const struct fb_videomode *)buf, i,
 179                                  &fb_info->modelist);
 180         if (fb_new_modelist(fb_info)) {
 181                 fb_destroy_modelist(&fb_info->modelist);
 182                 list_splice(&old_list, &fb_info->modelist);
 183         } else
 184                 fb_destroy_modelist(&old_list);
 185
 186         release_console_sem();
 187
 188         return 0;
 189 }
 190
 191 static ssize_t show_modes(struct device *device, struct device_attribute *attr,
 192                           char *buf)
 193 {
 194         struct fb_info *fb_info = dev_get_drvdata(device);
 195         unsigned int i;
 196         struct list_head *pos;
 197         struct fb_modelist *modelist;
 198         const struct fb_videomode *mode;
 199
 200         i = 0;
 201         list_for_each(pos, &fb_info->modelist) {
 202                 modelist = list_entry(pos, struct fb_modelist, list);
 203                 mode = &modelist->mode;
 204                 i += mode_string(buf, i, mode);
 205         }
 206         return i;
 207 }
 208
 209 static ssize_t store_bpp(struct device *device, struct device_attribute *attr,
 210                          const char *buf, size_t count)
 211 {
 212         struct fb_info *fb_info = dev_get_drvdata(device);
 213         struct fb_var_screeninfo var;
 214         char ** last = NULL;
 215         int err;
 216
 217         var = fb_info->var;
 218         var.bits_per_pixel = simple_strtoul(buf, last, 0);
 219         if ((err = activate(fb_info, &var)))
 220                 return err;
 221         return count;
 222 }
 223
 224 static ssize_t show_bpp(struct device *device, struct device_attribute *attr,
 225                         char *buf)
 226 {
 227         struct fb_info *fb_info = dev_get_drvdata(device);
 228         return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->var.bits_per_pixel);
 229 }
 230
 231 static ssize_t store_rotate(struct device *device,
 232                             struct device_attribute *attr,
 233                             const char *buf, size_t count)
 234 {
 235         struct fb_info *fb_info = dev_get_drvdata(device);
 236         struct fb_var_screeninfo var;
 237         char **last = NULL;
 238         int err;
 239
 240         var = fb_info->var;
 241         var.rotate = simple_strtoul(buf, last, 0);
 242
 243         if ((err = activate(fb_info, &var)))
 244                 return err;
 245
 246         return count;
 247 }
 248
 249
 250 static ssize_t show_rotate(struct device *device,
 251                            struct device_attribute *attr, char *buf)
 252 {
 253         struct fb_info *fb_info = dev_get_drvdata(device);
 254
 255         return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->var.rotate);
 256 }
 257
 258 static ssize_t store_virtual(struct device *device,
 259                              struct device_attribute *attr,
 260                              const char *buf, size_t count)
 261 {
 262         struct fb_info *fb_info = dev_get_drvdata(device);
 263         struct fb_var_screeninfo var;
 264         char *last = NULL;
 265         int err;
 266
 267         var = fb_info->var;
 268         var.xres_virtual = simple_strtoul(buf, &last, 0);
 269         last++;
 270         if (last - buf >= count)
 271                 return -EINVAL;
 272         var.yres_virtual = simple_strtoul(last, &last, 0);
 273
 274         if ((err = activate(fb_info, &var)))
 275                 return err;
 276         return count;
 277 }
 278
 279 static ssize_t show_virtual(struct device *device,
 280                             struct device_attribute *attr, char *buf)
 281 {
 282         struct fb_info *fb_info = dev_get_drvdata(device);
 283         return snprintf(buf, PAGE_SIZE, "%d,%d\n", fb_info->var.xres_virtual,
 284                         fb_info->var.yres_virtual);
 285 }
 286
 287 static ssize_t show_stride(struct device *device,
 288                            struct device_attribute *attr, char *buf)
 289 {
 290         struct fb_info *fb_info = dev_get_drvdata(device);
 291         return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->fix.line_length);
 292 }
 293
 294 static ssize_t store_blank(struct device *device,
 295                            struct device_attribute *attr,
 296                            const char *buf, size_t count)
 297 {
 298         struct fb_info *fb_info = dev_get_drvdata(device);
 299         char *last = NULL;
 300         int err;
 301
 302         acquire_console_sem();
 303         fb_info->flags |= FBINFO_MISC_USEREVENT;
 304         err = fb_blank(fb_info, simple_strtoul(buf, &last, 0));
 305         fb_info->flags &= ~FBINFO_MISC_USEREVENT;
 306         release_console_sem();
 307         if (err < 0)
 308                 return err;
 309         return count;
 310 }
 311
 312 static ssize_t show_blank(struct device *device,
 313                           struct device_attribute *attr, char *buf)
 314 {
 315 //      struct fb_info *fb_info = dev_get_drvdata(device);
 316         return 0;
 317 }
 318
 319 static ssize_t store_console(struct device *device,
 320                              struct device_attribute *attr,
 321                              const char *buf, size_t count)
 322 {
 323 //      struct fb_info *fb_info = dev_get_drvdata(device);
 324         return 0;
 325 }
 326
 327 static ssize_t show_console(struct device *device,
 328                             struct device_attribute *attr, char *buf)
 329 {
 330 //      struct fb_info *fb_info = dev_get_drvdata(device);
 331         return 0;
 332 }
 333
 334 static ssize_t store_cursor(struct device *device,
 335                             struct device_attribute *attr,
 336                             const char *buf, size_t count)
 337 {
 338 //      struct fb_info *fb_info = dev_get_drvdata(device);
 339         return 0;
 340 }
 341
 342 static ssize_t show_cursor(struct device *device,
 343                            struct device_attribute *attr, char *buf)
 344 {
 345 //      struct fb_info *fb_info = dev_get_drvdata(device);
 346         return 0;
 347 }
 348
 349 static ssize_t store_pan(struct device *device,
 350                          struct device_attribute *attr,
 351                          const char *buf, size_t count)
 352 {
 353         struct fb_info *fb_info = dev_get_drvdata(device);
 354         struct fb_var_screeninfo var;
 355         char *last = NULL;
 356         int err;
 357
 358         var = fb_info->var;
 359         var.xoffset = simple_strtoul(buf, &last, 0);
 360         last++;
 361         if (last - buf >= count)
 362                 return -EINVAL;
 363         var.yoffset = simple_strtoul(last, &last, 0);
 364
 365         acquire_console_sem();
 366         err = fb_pan_display(fb_info, &var);
 367         release_console_sem();
 368
 369         if (err < 0)
 370                 return err;
 371         return count;
 372 }
 373
 374 static ssize_t show_pan(struct device *device,
 375                         struct device_attribute *attr, char *buf)
 376 {
 377         struct fb_info *fb_info = dev_get_drvdata(device);
 378         return snprintf(buf, PAGE_SIZE, "%d,%d\n", fb_info->var.xoffset,
 379                         fb_info->var.yoffset);
 380 }
 381
 382 static ssize_t show_name(struct device *device,
 383                          struct device_attribute *attr, char *buf)
 384 {
 385         struct fb_info *fb_info = dev_get_drvdata(device);
 386
 387         return snprintf(buf, PAGE_SIZE, "%s\n", fb_info->fix.id);
 388 }
 389
 390 static ssize_t store_fbstate(struct device *device,
 391                              struct device_attribute *attr,
 392                              const char *buf, size_t count)
 393 {
 394         struct fb_info *fb_info = dev_get_drvdata(device);
 395         u32 state;
 396         char *last = NULL;
 397
 398         state = simple_strtoul(buf, &last, 0);
 399
 400         acquire_console_sem();
 401         fb_set_suspend(fb_info, (int)state);
 402         release_console_sem();
 403
 404         return count;
 405 }
 406
 407 static ssize_t show_fbstate(struct device *device,
 408                             struct device_attribute *attr, char *buf)
 409 {
 410         struct fb_info *fb_info = dev_get_drvdata(device);
 411         return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->state);
 412 }
 413
 414 #ifdef CONFIG_FB_BACKLIGHT
 415 static ssize_t store_bl_curve(struct device *device,
 416                               struct device_attribute *attr,
 417                               const char *buf, size_t count)
 418 {
 419         struct fb_info *fb_info = dev_get_drvdata(device);
 420         u8 tmp_curve[FB_BACKLIGHT_LEVELS];
 421         unsigned int i;
 422
 423         /* Some drivers don't use framebuffer_alloc(), but those also
 424          * don't have backlights.
 425          */
 426         if (!fb_info || !fb_info->bl_dev)
 427                 return -ENODEV;
 428
 429         if (count != (FB_BACKLIGHT_LEVELS / 8 * 24))
 430                 return -EINVAL;
 431
 432         for (i = 0; i < (FB_BACKLIGHT_LEVELS / 8); ++i)
 433                 if (sscanf(&buf[i * 24],
 434                         "%2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx\n",
 435                         &tmp_curve[i * 8 + 0],
 436                         &tmp_curve[i * 8 + 1],
 437                         &tmp_curve[i * 8 + 2],
 438                         &tmp_curve[i * 8 + 3],
 439                         &tmp_curve[i * 8 + 4],
 440                         &tmp_curve[i * 8 + 5],
 441                         &tmp_curve[i * 8 + 6],
 442                         &tmp_curve[i * 8 + 7]) != 8)
 443                         return -EINVAL;
 444
 445         /* If there has been an error in the input data, we won't
 446          * reach this loop.
 447          */
 448         mutex_lock(&fb_info->bl_curve_mutex);
 449         for (i = 0; i < FB_BACKLIGHT_LEVELS; ++i)
 450                 fb_info->bl_curve[i] = tmp_curve[i];
 451         mutex_unlock(&fb_info->bl_curve_mutex);
 452
 453         return count;
 454 }
 455
 456 static ssize_t show_bl_curve(struct device *device,
 457                              struct device_attribute *attr, char *buf)
 458 {
 459         struct fb_info *fb_info = dev_get_drvdata(device);
 460         ssize_t len = 0;
 461         unsigned int i;
 462
 463         /* Some drivers don't use framebuffer_alloc(), but those also
 464          * don't have backlights.
 465          */
 466         if (!fb_info || !fb_info->bl_dev)
 467                 return -ENODEV;
 468
 469         mutex_lock(&fb_info->bl_curve_mutex);
 470         for (i = 0; i < FB_BACKLIGHT_LEVELS; i += 8)
 471                 len += snprintf(&buf[len], PAGE_SIZE,
 472                                 "%02x %02x %02x %02x %02x %02x %02x %02x\n",
 473                                 fb_info->bl_curve[i + 0],
 474                                 fb_info->bl_curve[i + 1],
 475                                 fb_info->bl_curve[i + 2],
 476                                 fb_info->bl_curve[i + 3],
 477                                 fb_info->bl_curve[i + 4],
 478                                 fb_info->bl_curve[i + 5],
 479                                 fb_info->bl_curve[i + 6],
 480                                 fb_info->bl_curve[i + 7]);
 481         mutex_unlock(&fb_info->bl_curve_mutex);
 482
 483         return len;
 484 }
 485 #endif
 486
 487 /* When cmap is added back in it should be a binary attribute
 488  * not a text one. Consideration should also be given to converting
 489  * fbdev to use configfs instead of sysfs */
 490 static struct device_attribute device_attrs[] = {
 491         __ATTR(bits_per_pixel, S_IRUGO|S_IWUSR, show_bpp, store_bpp),
 492         __ATTR(blank, S_IRUGO|S_IWUSR, show_blank, store_blank),
 493         __ATTR(console, S_IRUGO|S_IWUSR, show_console, store_console),
 494         __ATTR(cursor, S_IRUGO|S_IWUSR, show_cursor, store_cursor),
 495         __ATTR(mode, S_IRUGO|S_IWUSR, show_mode, store_mode),
 496         __ATTR(modes, S_IRUGO|S_IWUSR, show_modes, store_modes),
 497         __ATTR(pan, S_IRUGO|S_IWUSR, show_pan, store_pan),
 498         __ATTR(virtual_size, S_IRUGO|S_IWUSR, show_virtual, store_virtual),
 499         __ATTR(name, S_IRUGO, show_name, NULL),
 500         __ATTR(stride, S_IRUGO, show_stride, NULL),
 501         __ATTR(rotate, S_IRUGO|S_IWUSR, show_rotate, store_rotate),
 502         __ATTR(state, S_IRUGO|S_IWUSR, show_fbstate, store_fbstate),
 503 #ifdef CONFIG_FB_BACKLIGHT
 504         __ATTR(bl_curve, S_IRUGO|S_IWUSR, show_bl_curve, store_bl_curve),
 505 #endif
 506 };
 507
 508 int fb_init_device(struct fb_info *fb_info)
 509 {
 510         int i, error = 0;
 511
 512         dev_set_drvdata(fb_info->dev, fb_info);
 513
 514         fb_info->class_flag |= FB_SYSFS_FLAG_ATTR;
 515
 516         for (i = 0; i < ARRAY_SIZE(device_attrs); i++) {
 517                 error = device_create_file(fb_info->dev, &device_attrs[i]);
 518
 519                 if (error)
 520                         break;
 521         }
 522
 523         if (error) {
 524                 while (--i >= 0)
 525                         device_remove_file(fb_info->dev, &device_attrs[i]);
 526                 fb_info->class_flag &= ~FB_SYSFS_FLAG_ATTR;
 527         }
 528
 529         return 0;
 530 }
 531
 532 void fb_cleanup_device(struct fb_info *fb_info)
 533 {
 534         unsigned int i;
 535
 536         if (fb_info->class_flag & FB_SYSFS_FLAG_ATTR) {
 537                 for (i = 0; i < ARRAY_SIZE(device_attrs); i++)
 538                         device_remove_file(fb_info->dev, &device_attrs[i]);
 539
 540                 fb_info->class_flag &= ~FB_SYSFS_FLAG_ATTR;
 541         }
 542 }
 543
 544 #ifdef CONFIG_FB_BACKLIGHT
 545 /* This function generates a linear backlight curve
 546  *
 547  *     0: off
 548  *   1-7: min
 549  * 8-127: linear from min to max
 550  */
 551 void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max)
 552 {
 553         unsigned int i, flat, count, range = (max - min);
 554
 555         mutex_lock(&fb_info->bl_curve_mutex);
 556
 557         fb_info->bl_curve[0] = off;
 558
 559         for (flat = 1; flat < (FB_BACKLIGHT_LEVELS / 16); ++flat)
 560                 fb_info->bl_curve[flat] = min;
 561
 562         count = FB_BACKLIGHT_LEVELS * 15 / 16;
 563         for (i = 0; i < count; ++i)
 564                 fb_info->bl_curve[flat + i] = min + (range * (i + 1) / count);
 565
 566         mutex_unlock(&fb_info->bl_curve_mutex);
 567 }
 568 EXPORT_SYMBOL_GPL(fb_bl_default_curve);
 569 #endif