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 += scnprintf(&buf[len], PAGE_SIZE - len, "%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 579