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