drivers/video/fbdev/core/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 occurred.
  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         if (!info)
  84                 return;
  85         kfree(info->apertures);
  86         kfree(info);
  87 }
  88 EXPORT_SYMBOL(framebuffer_release);
  89
  90 static int activate(struct fb_info *fb_info, struct fb_var_screeninfo *var)
  91 {
  92         int err;
  93
  94         var->activate |= FB_ACTIVATE_FORCE;
  95         console_lock();
  96         fb_info->flags |= FBINFO_MISC_USEREVENT;
  97         err = fb_set_var(fb_info, var);
  98         fb_info->flags &= ~FBINFO_MISC_USEREVENT;
  99         console_unlock();
 100         if (err)
 101                 return err;
 102         return 0;
 103 }
 104
 105 static int mode_string(char *buf, unsigned int offset,
 106                        const struct fb_videomode *mode)
 107 {
 108         char m = 'U';
 109         char v = 'p';
 110
 111         if (mode->flag & FB_MODE_IS_DETAILED)
 112                 m = 'D';
 113         if (mode->flag & FB_MODE_IS_VESA)
 114                 m = 'V';
 115         if (mode->flag & FB_MODE_IS_STANDARD)
 116                 m = 'S';
 117
 118         if (mode->vmode & FB_VMODE_INTERLACED)
 119                 v = 'i';
 120         if (mode->vmode & FB_VMODE_DOUBLE)
 121                 v = 'd';
 122
 123         return snprintf(&buf[offset], PAGE_SIZE - offset, "%c:%dx%d%c-%d\n",
 124                         m, mode->xres, mode->yres, v, mode->refresh);
 125 }
 126
 127 static ssize_t store_mode(struct device *device, struct device_attribute *attr,
 128                           const char *buf, size_t count)
 129 {
 130         struct fb_info *fb_info = dev_get_drvdata(device);
 131         char mstr[100];
 132         struct fb_var_screeninfo var;
 133         struct fb_modelist *modelist;
 134         struct fb_videomode *mode;
 135         struct list_head *pos;
 136         size_t i;
 137         int err;
 138
 139         memset(&var, 0, sizeof(var));
 140
 141         list_for_each(pos, &fb_info->modelist) {
 142                 modelist = list_entry(pos, struct fb_modelist, list);
 143                 mode = &modelist->mode;
 144                 i = mode_string(mstr, 0, mode);
 145                 if (strncmp(mstr, buf, max(count, i)) == 0) {
 146
 147                         var = fb_info->var;
 148                         fb_videomode_to_var(&var, mode);
 149                         if ((err = activate(fb_info, &var)))
 150                                 return err;
 151                         fb_info->mode = mode;
 152                         return count;
 153                 }
 154         }
 155         return -EINVAL;
 156 }
 157
 158 static ssize_t show_mode(struct device *device, struct device_attribute *attr,
 159                          char *buf)
 160 {
 161         struct fb_info *fb_info = dev_get_drvdata(device);
 162
 163         if (!fb_info->mode)
 164                 return 0;
 165
 166         return mode_string(buf, 0, fb_info->mode);
 167 }
 168
 169 static ssize_t store_modes(struct device *device,
 170                            struct device_attribute *attr,
 171                            const char *buf, size_t count)
 172 {
 173         struct fb_info *fb_info = dev_get_drvdata(device);
 174         LIST_HEAD(old_list);
 175         int i = count / sizeof(struct fb_videomode);
 176
 177         if (i * sizeof(struct fb_videomode) != count)
 178                 return -EINVAL;
 179
 180         console_lock();
 181         if (!lock_fb_info(fb_info)) {
 182                 console_unlock();
 183                 return -ENODEV;
 184         }
 185
 186         list_splice(&fb_info->modelist, &old_list);
 187         fb_videomode_to_modelist((const struct fb_videomode *)buf, i,
 188                                  &fb_info->modelist);
 189         if (fb_new_modelist(fb_info)) {
 190                 fb_destroy_modelist(&fb_info->modelist);
 191                 list_splice(&old_list, &fb_info->modelist);
 192         } else
 193                 fb_destroy_modelist(&old_list);
 194
 195         unlock_fb_info(fb_info);
 196         console_unlock();
 197
 198         return 0;
 199 }
 200
 201 static ssize_t show_modes(struct device *device, struct device_attribute *attr,
 202                           char *buf)
 203 {
 204         struct fb_info *fb_info = dev_get_drvdata(device);
 205         unsigned int i;
 206         struct list_head *pos;
 207         struct fb_modelist *modelist;
 208         const struct fb_videomode *mode;
 209
 210         i = 0;
 211         list_for_each(pos, &fb_info->modelist) {
 212                 modelist = list_entry(pos, struct fb_modelist, list);
 213                 mode = &modelist->mode;
 214                 i += mode_string(buf, i, mode);
 215         }
 216         return i;
 217 }
 218
 219 static ssize_t store_bpp(struct device *device, struct device_attribute *attr,
 220                          const char *buf, size_t count)
 221 {
 222         struct fb_info *fb_info = dev_get_drvdata(device);
 223         struct fb_var_screeninfo var;
 224         char ** last = NULL;
 225         int err;
 226
 227         var = fb_info->var;
 228         var.bits_per_pixel = simple_strtoul(buf, last, 0);
 229         if ((err = activate(fb_info, &var)))
 230                 return err;
 231         return count;
 232 }
 233
 234 static ssize_t show_bpp(struct device *device, struct device_attribute *attr,
 235                         char *buf)
 236 {
 237         struct fb_info *fb_info = dev_get_drvdata(device);
 238         return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->var.bits_per_pixel);
 239 }
 240
 241 static ssize_t store_rotate(struct device *device,
 242                             struct device_attribute *attr,
 243                             const char *buf, size_t count)
 244 {
 245         struct fb_info *fb_info = dev_get_drvdata(device);
 246         struct fb_var_screeninfo var;
 247         char **last = NULL;
 248         int err;
 249
 250         var = fb_info->var;
 251         var.rotate = simple_strtoul(buf, last, 0);
 252
 253         if ((err = activate(fb_info, &var)))
 254                 return err;
 255
 256         return count;
 257 }
 258
 259
 260 static ssize_t show_rotate(struct device *device,
 261                            struct device_attribute *attr, char *buf)
 262 {
 263         struct fb_info *fb_info = dev_get_drvdata(device);
 264
 265         return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->var.rotate);
 266 }
 267
 268 static ssize_t store_virtual(struct device *device,
 269                              struct device_attribute *attr,
 270                              const char *buf, size_t count)
 271 {
 272         struct fb_info *fb_info = dev_get_drvdata(device);
 273         struct fb_var_screeninfo var;
 274         char *last = NULL;
 275         int err;
 276
 277         var = fb_info->var;
 278         var.xres_virtual = simple_strtoul(buf, &last, 0);
 279         last++;
 280         if (last - buf >= count)
 281                 return -EINVAL;
 282         var.yres_virtual = simple_strtoul(last, &last, 0);
 283
 284         if ((err = activate(fb_info, &var)))
 285                 return err;
 286         return count;
 287 }
 288
 289 static ssize_t show_virtual(struct device *device,
 290                             struct device_attribute *attr, char *buf)
 291 {
 292         struct fb_info *fb_info = dev_get_drvdata(device);
 293         return snprintf(buf, PAGE_SIZE, "%d,%d\n", fb_info->var.xres_virtual,
 294                         fb_info->var.yres_virtual);
 295 }
 296
 297 static ssize_t show_stride(struct device *device,
 298                            struct device_attribute *attr, char *buf)
 299 {
 300         struct fb_info *fb_info = dev_get_drvdata(device);
 301         return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->fix.line_length);
 302 }
 303
 304 static ssize_t store_blank(struct device *device,
 305                            struct device_attribute *attr,
 306                            const char *buf, size_t count)
 307 {
 308         struct fb_info *fb_info = dev_get_drvdata(device);
 309         char *last = NULL;
 310         int err;
 311
 312         console_lock();
 313         fb_info->flags |= FBINFO_MISC_USEREVENT;
 314         err = fb_blank(fb_info, simple_strtoul(buf, &last, 0));
 315         fb_info->flags &= ~FBINFO_MISC_USEREVENT;
 316         console_unlock();
 317         if (err < 0)
 318                 return err;
 319         return count;
 320 }
 321
 322 static ssize_t show_blank(struct device *device,
 323                           struct device_attribute *attr, char *buf)
 324 {
 325 //      struct fb_info *fb_info = dev_get_drvdata(device);
 326         return 0;
 327 }
 328
 329 static ssize_t store_console(struct device *device,
 330                              struct device_attribute *attr,
 331                              const char *buf, size_t count)
 332 {
 333 //      struct fb_info *fb_info = dev_get_drvdata(device);
 334         return 0;
 335 }
 336
 337 static ssize_t show_console(struct device *device,
 338                             struct device_attribute *attr, char *buf)
 339 {
 340 //      struct fb_info *fb_info = dev_get_drvdata(device);
 341         return 0;
 342 }
 343
 344 static ssize_t store_cursor(struct device *device,
 345                             struct device_attribute *attr,
 346                             const char *buf, size_t count)
 347 {
 348 //      struct fb_info *fb_info = dev_get_drvdata(device);
 349         return 0;
 350 }
 351
 352 static ssize_t show_cursor(struct device *device,
 353                            struct device_attribute *attr, char *buf)
 354 {
 355 //      struct fb_info *fb_info = dev_get_drvdata(device);
 356         return 0;
 357 }
 358
 359 static ssize_t store_pan(struct device *device,
 360                          struct device_attribute *attr,
 361                          const char *buf, size_t count)
 362 {
 363         struct fb_info *fb_info = dev_get_drvdata(device);
 364         struct fb_var_screeninfo var;
 365         char *last = NULL;
 366         int err;
 367
 368         var = fb_info->var;
 369         var.xoffset = simple_strtoul(buf, &last, 0);
 370         last++;
 371         if (last - buf >= count)
 372                 return -EINVAL;
 373         var.yoffset = simple_strtoul(last, &last, 0);
 374
 375         console_lock();
 376         err = fb_pan_display(fb_info, &var);
 377         console_unlock();
 378
 379         if (err < 0)
 380                 return err;
 381         return count;
 382 }
 383
 384 static ssize_t show_pan(struct device *device,
 385                         struct device_attribute *attr, char *buf)
 386 {
 387         struct fb_info *fb_info = dev_get_drvdata(device);
 388         return snprintf(buf, PAGE_SIZE, "%d,%d\n", fb_info->var.xoffset,
 389                         fb_info->var.yoffset);
 390 }
 391
 392 static ssize_t show_name(struct device *device,
 393                          struct device_attribute *attr, char *buf)
 394 {
 395         struct fb_info *fb_info = dev_get_drvdata(device);
 396
 397         return snprintf(buf, PAGE_SIZE, "%s\n", fb_info->fix.id);
 398 }
 399
 400 static ssize_t store_fbstate(struct device *device,
 401                              struct device_attribute *attr,
 402                              const char *buf, size_t count)
 403 {
 404         struct fb_info *fb_info = dev_get_drvdata(device);
 405         u32 state;
 406         char *last = NULL;
 407
 408         state = simple_strtoul(buf, &last, 0);
 409
 410         console_lock();
 411         if (!lock_fb_info(fb_info)) {
 412                 console_unlock();
 413                 return -ENODEV;
 414         }
 415
 416         fb_set_suspend(fb_info, (int)state);
 417
 418         unlock_fb_info(fb_info);
 419         console_unlock();
 420
 421         return count;
 422 }
 423
 424 static ssize_t show_fbstate(struct device *device,
 425                             struct device_attribute *attr, char *buf)
 426 {
 427         struct fb_info *fb_info = dev_get_drvdata(device);
 428         return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->state);
 429 }
 430
 431 #ifdef CONFIG_FB_BACKLIGHT
 432 static ssize_t store_bl_curve(struct device *device,
 433                               struct device_attribute *attr,
 434                               const char *buf, size_t count)
 435 {
 436         struct fb_info *fb_info = dev_get_drvdata(device);
 437         u8 tmp_curve[FB_BACKLIGHT_LEVELS];
 438         unsigned int i;
 439
 440         /* Some drivers don't use framebuffer_alloc(), but those also
 441          * don't have backlights.
 442          */
 443         if (!fb_info || !fb_info->bl_dev)
 444                 return -ENODEV;
 445
 446         if (count != (FB_BACKLIGHT_LEVELS / 8 * 24))
 447                 return -EINVAL;
 448
 449         for (i = 0; i < (FB_BACKLIGHT_LEVELS / 8); ++i)
 450                 if (sscanf(&buf[i * 24],
 451                         "%2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx\n",
 452                         &tmp_curve[i * 8 + 0],
 453                         &tmp_curve[i * 8 + 1],
 454                         &tmp_curve[i * 8 + 2],
 455                         &tmp_curve[i * 8 + 3],
 456                         &tmp_curve[i * 8 + 4],
 457                         &tmp_curve[i * 8 + 5],
 458                         &tmp_curve[i * 8 + 6],
 459                         &tmp_curve[i * 8 + 7]) != 8)
 460                         return -EINVAL;
 461
 462         /* If there has been an error in the input data, we won't
 463          * reach this loop.
 464          */
 465         mutex_lock(&fb_info->bl_curve_mutex);
 466         for (i = 0; i < FB_BACKLIGHT_LEVELS; ++i)
 467                 fb_info->bl_curve[i] = tmp_curve[i];
 468         mutex_unlock(&fb_info->bl_curve_mutex);
 469
 470         return count;
 471 }
 472
 473 static ssize_t show_bl_curve(struct device *device,
 474                              struct device_attribute *attr, char *buf)
 475 {
 476         struct fb_info *fb_info = dev_get_drvdata(device);
 477         ssize_t len = 0;
 478         unsigned int i;
 479
 480         /* Some drivers don't use framebuffer_alloc(), but those also
 481          * don't have backlights.
 482          */
 483         if (!fb_info || !fb_info->bl_dev)
 484                 return -ENODEV;
 485
 486         mutex_lock(&fb_info->bl_curve_mutex);
 487         for (i = 0; i < FB_BACKLIGHT_LEVELS; i += 8)
 488                 len += snprintf(&buf[len], PAGE_SIZE, "%8ph\n",
 489                                 fb_info->bl_curve + i);
 490         mutex_unlock(&fb_info->bl_curve_mutex);
 491
 492         return len;
 493 }
 494 #endif
 495
 496 /* When cmap is added back in it should be a binary attribute
 497  * not a text one. Consideration should also be given to converting
 498  * fbdev to use configfs instead of sysfs */
 499 static struct device_attribute device_attrs[] = {
 500         __ATTR(bits_per_pixel, S_IRUGO|S_IWUSR, show_bpp, store_bpp),
 501         __ATTR(blank, S_IRUGO|S_IWUSR, show_blank, store_blank),
 502         __ATTR(console, S_IRUGO|S_IWUSR, show_console, store_console),
 503         __ATTR(cursor, S_IRUGO|S_IWUSR, show_cursor, store_cursor),
 504         __ATTR(mode, S_IRUGO|S_IWUSR, show_mode, store_mode),
 505         __ATTR(modes, S_IRUGO|S_IWUSR, show_modes, store_modes),
 506         __ATTR(pan, S_IRUGO|S_IWUSR, show_pan, store_pan),
 507         __ATTR(virtual_size, S_IRUGO|S_IWUSR, show_virtual, store_virtual),
 508         __ATTR(name, S_IRUGO, show_name, NULL),
 509         __ATTR(stride, S_IRUGO, show_stride, NULL),
 510         __ATTR(rotate, S_IRUGO|S_IWUSR, show_rotate, store_rotate),
 511         __ATTR(state, S_IRUGO|S_IWUSR, show_fbstate, store_fbstate),
 512 #ifdef CONFIG_FB_BACKLIGHT
 513         __ATTR(bl_curve, S_IRUGO|S_IWUSR, show_bl_curve, store_bl_curve),
 514 #endif
 515 };
 516
 517 int fb_init_device(struct fb_info *fb_info)
 518 {
 519         int i, error = 0;
 520
 521         dev_set_drvdata(fb_info->dev, fb_info);
 522
 523         fb_info->class_flag |= FB_SYSFS_FLAG_ATTR;
 524
 525         for (i = 0; i < ARRAY_SIZE(device_attrs); i++) {
 526                 error = device_create_file(fb_info->dev, &device_attrs[i]);
 527
 528                 if (error)
 529                         break;
 530         }
 531
 532         if (error) {
 533                 while (--i >= 0)
 534                         device_remove_file(fb_info->dev, &device_attrs[i]);
 535                 fb_info->class_flag &= ~FB_SYSFS_FLAG_ATTR;
 536         }
 537
 538         return 0;
 539 }
 540
 541 void fb_cleanup_device(struct fb_info *fb_info)
 542 {
 543         unsigned int i;
 544
 545         if (fb_info->class_flag & FB_SYSFS_FLAG_ATTR) {
 546                 for (i = 0; i < ARRAY_SIZE(device_attrs); i++)
 547                         device_remove_file(fb_info->dev, &device_attrs[i]);
 548
 549                 fb_info->class_flag &= ~FB_SYSFS_FLAG_ATTR;
 550         }
 551 }
 552
 553 #ifdef CONFIG_FB_BACKLIGHT
 554 /* This function generates a linear backlight curve
 555  *
 556  *     0: off
 557  *   1-7: min
 558  * 8-127: linear from min to max
 559  */
 560 void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max)
 561 {
 562         unsigned int i, flat, count, range = (max - min);
 563
 564         mutex_lock(&fb_info->bl_curve_mutex);
 565
 566         fb_info->bl_curve[0] = off;
 567
 568         for (flat = 1; flat < (FB_BACKLIGHT_LEVELS / 16); ++flat)
 569                 fb_info->bl_curve[flat] = min;
 570
 571         count = FB_BACKLIGHT_LEVELS * 15 / 16;
 572         for (i = 0; i < count; ++i)
 573                 fb_info->bl_curve[flat + i] = min + (range * (i + 1) / count);
 574
 575         mutex_unlock(&fb_info->bl_curve_mutex);
 576 }
 577 EXPORT_SYMBOL_GPL(fb_bl_default_curve);
 578 #endif