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 */
framebuffer_alloc(size_t size,struct device * dev)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 */
framebuffer_release(struct fb_info * info)81 void framebuffer_release(struct fb_info *info)
82 {
83 kfree(info->apertures);
84 kfree(info);
85 }
86 EXPORT_SYMBOL(framebuffer_release);
87
activate(struct fb_info * fb_info,struct fb_var_screeninfo * var)88 static int activate(struct fb_info *fb_info, struct fb_var_screeninfo *var)
89 {
90 int err;
91
92 var->activate |= FB_ACTIVATE_FORCE;
93 console_lock();
94 fb_info->flags |= FBINFO_MISC_USEREVENT;
95 err = fb_set_var(fb_info, var);
96 fb_info->flags &= ~FBINFO_MISC_USEREVENT;
97 console_unlock();
98 if (err)
99 return err;
100 return 0;
101 }
102
mode_string(char * buf,unsigned int offset,const struct fb_videomode * mode)103 static int mode_string(char *buf, unsigned int offset,
104 const struct fb_videomode *mode)
105 {
106 char m = 'U';
107 char v = 'p';
108
109 if (mode->flag & FB_MODE_IS_DETAILED)
110 m = 'D';
111 if (mode->flag & FB_MODE_IS_VESA)
112 m = 'V';
113 if (mode->flag & FB_MODE_IS_STANDARD)
114 m = 'S';
115
116 if (mode->vmode & FB_VMODE_INTERLACED)
117 v = 'i';
118 if (mode->vmode & FB_VMODE_DOUBLE)
119 v = 'd';
120
121 return snprintf(&buf[offset], PAGE_SIZE - offset, "%c:%dx%d%c-%d\n",
122 m, mode->xres, mode->yres, v, mode->refresh);
123 }
124
store_mode(struct device * device,struct device_attribute * attr,const char * buf,size_t count)125 static ssize_t store_mode(struct device *device, struct device_attribute *attr,
126 const char *buf, size_t count)
127 {
128 struct fb_info *fb_info = dev_get_drvdata(device);
129 char mstr[100];
130 struct fb_var_screeninfo var;
131 struct fb_modelist *modelist;
132 struct fb_videomode *mode;
133 struct list_head *pos;
134 size_t i;
135 int err;
136
137 memset(&var, 0, sizeof(var));
138
139 list_for_each(pos, &fb_info->modelist) {
140 modelist = list_entry(pos, struct fb_modelist, list);
141 mode = &modelist->mode;
142 i = mode_string(mstr, 0, mode);
143 if (strncmp(mstr, buf, max(count, i)) == 0) {
144
145 var = fb_info->var;
146 fb_videomode_to_var(&var, mode);
147 if ((err = activate(fb_info, &var)))
148 return err;
149 fb_info->mode = mode;
150 return count;
151 }
152 }
153 return -EINVAL;
154 }
155
show_mode(struct device * device,struct device_attribute * attr,char * buf)156 static ssize_t show_mode(struct device *device, struct device_attribute *attr,
157 char *buf)
158 {
159 struct fb_info *fb_info = dev_get_drvdata(device);
160
161 if (!fb_info->mode)
162 return 0;
163
164 return mode_string(buf, 0, fb_info->mode);
165 }
166
store_modes(struct device * device,struct device_attribute * attr,const char * buf,size_t count)167 static ssize_t store_modes(struct device *device,
168 struct device_attribute *attr,
169 const char *buf, size_t count)
170 {
171 struct fb_info *fb_info = dev_get_drvdata(device);
172 LIST_HEAD(old_list);
173 int i = count / sizeof(struct fb_videomode);
174
175 if (i * sizeof(struct fb_videomode) != count)
176 return -EINVAL;
177
178 if (!lock_fb_info(fb_info))
179 return -ENODEV;
180 console_lock();
181 list_splice(&fb_info->modelist, &old_list);
182 fb_videomode_to_modelist((const struct fb_videomode *)buf, i,
183 &fb_info->modelist);
184 if (fb_new_modelist(fb_info)) {
185 fb_destroy_modelist(&fb_info->modelist);
186 list_splice(&old_list, &fb_info->modelist);
187 } else
188 fb_destroy_modelist(&old_list);
189
190 console_unlock();
191 unlock_fb_info(fb_info);
192
193 return 0;
194 }
195
show_modes(struct device * device,struct device_attribute * attr,char * buf)196 static ssize_t show_modes(struct device *device, struct device_attribute *attr,
197 char *buf)
198 {
199 struct fb_info *fb_info = dev_get_drvdata(device);
200 unsigned int i;
201 struct list_head *pos;
202 struct fb_modelist *modelist;
203 const struct fb_videomode *mode;
204
205 i = 0;
206 list_for_each(pos, &fb_info->modelist) {
207 modelist = list_entry(pos, struct fb_modelist, list);
208 mode = &modelist->mode;
209 i += mode_string(buf, i, mode);
210 }
211 return i;
212 }
213
store_bpp(struct device * device,struct device_attribute * attr,const char * buf,size_t count)214 static ssize_t store_bpp(struct device *device, struct device_attribute *attr,
215 const char *buf, size_t count)
216 {
217 struct fb_info *fb_info = dev_get_drvdata(device);
218 struct fb_var_screeninfo var;
219 char ** last = NULL;
220 int err;
221
222 var = fb_info->var;
223 var.bits_per_pixel = simple_strtoul(buf, last, 0);
224 if ((err = activate(fb_info, &var)))
225 return err;
226 return count;
227 }
228
show_bpp(struct device * device,struct device_attribute * attr,char * buf)229 static ssize_t show_bpp(struct device *device, struct device_attribute *attr,
230 char *buf)
231 {
232 struct fb_info *fb_info = dev_get_drvdata(device);
233 return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->var.bits_per_pixel);
234 }
235
store_rotate(struct device * device,struct device_attribute * attr,const char * buf,size_t count)236 static ssize_t store_rotate(struct device *device,
237 struct device_attribute *attr,
238 const char *buf, size_t count)
239 {
240 struct fb_info *fb_info = dev_get_drvdata(device);
241 struct fb_var_screeninfo var;
242 char **last = NULL;
243 int err;
244
245 var = fb_info->var;
246 var.rotate = simple_strtoul(buf, last, 0);
247
248 if ((err = activate(fb_info, &var)))
249 return err;
250
251 return count;
252 }
253
254
show_rotate(struct device * device,struct device_attribute * attr,char * buf)255 static ssize_t show_rotate(struct device *device,
256 struct device_attribute *attr, char *buf)
257 {
258 struct fb_info *fb_info = dev_get_drvdata(device);
259
260 return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->var.rotate);
261 }
262
store_virtual(struct device * device,struct device_attribute * attr,const char * buf,size_t count)263 static ssize_t store_virtual(struct device *device,
264 struct device_attribute *attr,
265 const char *buf, size_t count)
266 {
267 struct fb_info *fb_info = dev_get_drvdata(device);
268 struct fb_var_screeninfo var;
269 char *last = NULL;
270 int err;
271
272 var = fb_info->var;
273 var.xres_virtual = simple_strtoul(buf, &last, 0);
274 last++;
275 if (last - buf >= count)
276 return -EINVAL;
277 var.yres_virtual = simple_strtoul(last, &last, 0);
278
279 if ((err = activate(fb_info, &var)))
280 return err;
281 return count;
282 }
283
show_virtual(struct device * device,struct device_attribute * attr,char * buf)284 static ssize_t show_virtual(struct device *device,
285 struct device_attribute *attr, char *buf)
286 {
287 struct fb_info *fb_info = dev_get_drvdata(device);
288 return snprintf(buf, PAGE_SIZE, "%d,%d\n", fb_info->var.xres_virtual,
289 fb_info->var.yres_virtual);
290 }
291
show_stride(struct device * device,struct device_attribute * attr,char * buf)292 static ssize_t show_stride(struct device *device,
293 struct device_attribute *attr, char *buf)
294 {
295 struct fb_info *fb_info = dev_get_drvdata(device);
296 return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->fix.line_length);
297 }
298
store_blank(struct device * device,struct device_attribute * attr,const char * buf,size_t count)299 static ssize_t store_blank(struct device *device,
300 struct device_attribute *attr,
301 const char *buf, size_t count)
302 {
303 struct fb_info *fb_info = dev_get_drvdata(device);
304 char *last = NULL;
305 int err;
306
307 console_lock();
308 fb_info->flags |= FBINFO_MISC_USEREVENT;
309 err = fb_blank(fb_info, simple_strtoul(buf, &last, 0));
310 fb_info->flags &= ~FBINFO_MISC_USEREVENT;
311 console_unlock();
312 if (err < 0)
313 return err;
314 return count;
315 }
316
show_blank(struct device * device,struct device_attribute * attr,char * buf)317 static ssize_t show_blank(struct device *device,
318 struct device_attribute *attr, char *buf)
319 {
320 // struct fb_info *fb_info = dev_get_drvdata(device);
321 return 0;
322 }
323
store_console(struct device * device,struct device_attribute * attr,const char * buf,size_t count)324 static ssize_t store_console(struct device *device,
325 struct device_attribute *attr,
326 const char *buf, size_t count)
327 {
328 // struct fb_info *fb_info = dev_get_drvdata(device);
329 return 0;
330 }
331
show_console(struct device * device,struct device_attribute * attr,char * buf)332 static ssize_t show_console(struct device *device,
333 struct device_attribute *attr, char *buf)
334 {
335 // struct fb_info *fb_info = dev_get_drvdata(device);
336 return 0;
337 }
338
store_cursor(struct device * device,struct device_attribute * attr,const char * buf,size_t count)339 static ssize_t store_cursor(struct device *device,
340 struct device_attribute *attr,
341 const char *buf, size_t count)
342 {
343 // struct fb_info *fb_info = dev_get_drvdata(device);
344 return 0;
345 }
346
show_cursor(struct device * device,struct device_attribute * attr,char * buf)347 static ssize_t show_cursor(struct device *device,
348 struct device_attribute *attr, char *buf)
349 {
350 // struct fb_info *fb_info = dev_get_drvdata(device);
351 return 0;
352 }
353
store_pan(struct device * device,struct device_attribute * attr,const char * buf,size_t count)354 static ssize_t store_pan(struct device *device,
355 struct device_attribute *attr,
356 const char *buf, size_t count)
357 {
358 struct fb_info *fb_info = dev_get_drvdata(device);
359 struct fb_var_screeninfo var;
360 char *last = NULL;
361 int err;
362
363 var = fb_info->var;
364 var.xoffset = simple_strtoul(buf, &last, 0);
365 last++;
366 if (last - buf >= count)
367 return -EINVAL;
368 var.yoffset = simple_strtoul(last, &last, 0);
369
370 console_lock();
371 err = fb_pan_display(fb_info, &var);
372 console_unlock();
373
374 if (err < 0)
375 return err;
376 return count;
377 }
378
show_pan(struct device * device,struct device_attribute * attr,char * buf)379 static ssize_t show_pan(struct device *device,
380 struct device_attribute *attr, char *buf)
381 {
382 struct fb_info *fb_info = dev_get_drvdata(device);
383 return snprintf(buf, PAGE_SIZE, "%d,%d\n", fb_info->var.xoffset,
384 fb_info->var.yoffset);
385 }
386
show_name(struct device * device,struct device_attribute * attr,char * buf)387 static ssize_t show_name(struct device *device,
388 struct device_attribute *attr, char *buf)
389 {
390 struct fb_info *fb_info = dev_get_drvdata(device);
391
392 return snprintf(buf, PAGE_SIZE, "%s\n", fb_info->fix.id);
393 }
394
store_fbstate(struct device * device,struct device_attribute * attr,const char * buf,size_t count)395 static ssize_t store_fbstate(struct device *device,
396 struct device_attribute *attr,
397 const char *buf, size_t count)
398 {
399 struct fb_info *fb_info = dev_get_drvdata(device);
400 u32 state;
401 char *last = NULL;
402
403 state = simple_strtoul(buf, &last, 0);
404
405 if (!lock_fb_info(fb_info))
406 return -ENODEV;
407 console_lock();
408 fb_set_suspend(fb_info, (int)state);
409 console_unlock();
410 unlock_fb_info(fb_info);
411
412 return count;
413 }
414
show_fbstate(struct device * device,struct device_attribute * attr,char * buf)415 static ssize_t show_fbstate(struct device *device,
416 struct device_attribute *attr, char *buf)
417 {
418 struct fb_info *fb_info = dev_get_drvdata(device);
419 return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->state);
420 }
421
422 #ifdef CONFIG_FB_BACKLIGHT
store_bl_curve(struct device * device,struct device_attribute * attr,const char * buf,size_t count)423 static ssize_t store_bl_curve(struct device *device,
424 struct device_attribute *attr,
425 const char *buf, size_t count)
426 {
427 struct fb_info *fb_info = dev_get_drvdata(device);
428 u8 tmp_curve[FB_BACKLIGHT_LEVELS];
429 unsigned int i;
430
431 /* Some drivers don't use framebuffer_alloc(), but those also
432 * don't have backlights.
433 */
434 if (!fb_info || !fb_info->bl_dev)
435 return -ENODEV;
436
437 if (count != (FB_BACKLIGHT_LEVELS / 8 * 24))
438 return -EINVAL;
439
440 for (i = 0; i < (FB_BACKLIGHT_LEVELS / 8); ++i)
441 if (sscanf(&buf[i * 24],
442 "%2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx\n",
443 &tmp_curve[i * 8 + 0],
444 &tmp_curve[i * 8 + 1],
445 &tmp_curve[i * 8 + 2],
446 &tmp_curve[i * 8 + 3],
447 &tmp_curve[i * 8 + 4],
448 &tmp_curve[i * 8 + 5],
449 &tmp_curve[i * 8 + 6],
450 &tmp_curve[i * 8 + 7]) != 8)
451 return -EINVAL;
452
453 /* If there has been an error in the input data, we won't
454 * reach this loop.
455 */
456 mutex_lock(&fb_info->bl_curve_mutex);
457 for (i = 0; i < FB_BACKLIGHT_LEVELS; ++i)
458 fb_info->bl_curve[i] = tmp_curve[i];
459 mutex_unlock(&fb_info->bl_curve_mutex);
460
461 return count;
462 }
463
show_bl_curve(struct device * device,struct device_attribute * attr,char * buf)464 static ssize_t show_bl_curve(struct device *device,
465 struct device_attribute *attr, char *buf)
466 {
467 struct fb_info *fb_info = dev_get_drvdata(device);
468 ssize_t len = 0;
469 unsigned int i;
470
471 /* Some drivers don't use framebuffer_alloc(), but those also
472 * don't have backlights.
473 */
474 if (!fb_info || !fb_info->bl_dev)
475 return -ENODEV;
476
477 mutex_lock(&fb_info->bl_curve_mutex);
478 for (i = 0; i < FB_BACKLIGHT_LEVELS; i += 8)
479 len += snprintf(&buf[len], PAGE_SIZE,
480 "%02x %02x %02x %02x %02x %02x %02x %02x\n",
481 fb_info->bl_curve[i + 0],
482 fb_info->bl_curve[i + 1],
483 fb_info->bl_curve[i + 2],
484 fb_info->bl_curve[i + 3],
485 fb_info->bl_curve[i + 4],
486 fb_info->bl_curve[i + 5],
487 fb_info->bl_curve[i + 6],
488 fb_info->bl_curve[i + 7]);
489 mutex_unlock(&fb_info->bl_curve_mutex);
490
491 return len;
492 }
493 #endif
494
495 /* When cmap is added back in it should be a binary attribute
496 * not a text one. Consideration should also be given to converting
497 * fbdev to use configfs instead of sysfs */
498 static struct device_attribute device_attrs[] = {
499 __ATTR(bits_per_pixel, S_IRUGO|S_IWUSR, show_bpp, store_bpp),
500 __ATTR(blank, S_IRUGO|S_IWUSR, show_blank, store_blank),
501 __ATTR(console, S_IRUGO|S_IWUSR, show_console, store_console),
502 __ATTR(cursor, S_IRUGO|S_IWUSR, show_cursor, store_cursor),
503 __ATTR(mode, S_IRUGO|S_IWUSR, show_mode, store_mode),
504 __ATTR(modes, S_IRUGO|S_IWUSR, show_modes, store_modes),
505 __ATTR(pan, S_IRUGO|S_IWUSR, show_pan, store_pan),
506 __ATTR(virtual_size, S_IRUGO|S_IWUSR, show_virtual, store_virtual),
507 __ATTR(name, S_IRUGO, show_name, NULL),
508 __ATTR(stride, S_IRUGO, show_stride, NULL),
509 __ATTR(rotate, S_IRUGO|S_IWUSR, show_rotate, store_rotate),
510 __ATTR(state, S_IRUGO|S_IWUSR, show_fbstate, store_fbstate),
511 #ifdef CONFIG_FB_BACKLIGHT
512 __ATTR(bl_curve, S_IRUGO|S_IWUSR, show_bl_curve, store_bl_curve),
513 #endif
514 };
515
fb_init_device(struct fb_info * fb_info)516 int fb_init_device(struct fb_info *fb_info)
517 {
518 int i, error = 0;
519
520 dev_set_drvdata(fb_info->dev, fb_info);
521
522 fb_info->class_flag |= FB_SYSFS_FLAG_ATTR;
523
524 for (i = 0; i < ARRAY_SIZE(device_attrs); i++) {
525 error = device_create_file(fb_info->dev, &device_attrs[i]);
526
527 if (error)
528 break;
529 }
530
531 if (error) {
532 while (--i >= 0)
533 device_remove_file(fb_info->dev, &device_attrs[i]);
534 fb_info->class_flag &= ~FB_SYSFS_FLAG_ATTR;
535 }
536
537 return 0;
538 }
539
fb_cleanup_device(struct fb_info * fb_info)540 void fb_cleanup_device(struct fb_info *fb_info)
541 {
542 unsigned int i;
543
544 if (fb_info->class_flag & FB_SYSFS_FLAG_ATTR) {
545 for (i = 0; i < ARRAY_SIZE(device_attrs); i++)
546 device_remove_file(fb_info->dev, &device_attrs[i]);
547
548 fb_info->class_flag &= ~FB_SYSFS_FLAG_ATTR;
549 }
550 }
551
552 #ifdef CONFIG_FB_BACKLIGHT
553 /* This function generates a linear backlight curve
554 *
555 * 0: off
556 * 1-7: min
557 * 8-127: linear from min to max
558 */
fb_bl_default_curve(struct fb_info * fb_info,u8 off,u8 min,u8 max)559 void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max)
560 {
561 unsigned int i, flat, count, range = (max - min);
562
563 mutex_lock(&fb_info->bl_curve_mutex);
564
565 fb_info->bl_curve[0] = off;
566
567 for (flat = 1; flat < (FB_BACKLIGHT_LEVELS / 16); ++flat)
568 fb_info->bl_curve[flat] = min;
569
570 count = FB_BACKLIGHT_LEVELS * 15 / 16;
571 for (i = 0; i < count; ++i)
572 fb_info->bl_curve[flat + i] = min + (range * (i + 1) / count);
573
574 mutex_unlock(&fb_info->bl_curve_mutex);
575 }
576 EXPORT_SYMBOL_GPL(fb_bl_default_curve);
577 #endif
578