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1/*
2 * Routines for driver control interface
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22#include <linux/threads.h>
23#include <linux/interrupt.h>
24#include <linux/slab.h>
25#include <linux/vmalloc.h>
26#include <linux/time.h>
27#include <sound/core.h>
28#include <sound/minors.h>
29#include <sound/info.h>
30#include <sound/control.h>
31
32/* max number of user-defined controls */
33#define MAX_USER_CONTROLS 32
34#define MAX_CONTROL_COUNT 1028
35
36struct snd_kctl_ioctl {
37 struct list_head list; /* list of all ioctls */
38 snd_kctl_ioctl_func_t fioctl;
39};
40
41static DECLARE_RWSEM(snd_ioctl_rwsem);
42static LIST_HEAD(snd_control_ioctls);
43#ifdef CONFIG_COMPAT
44static LIST_HEAD(snd_control_compat_ioctls);
45#endif
46
47static int snd_ctl_open(struct inode *inode, struct file *file)
48{
49 unsigned long flags;
50 struct snd_card *card;
51 struct snd_ctl_file *ctl;
52 int err;
53
54 err = nonseekable_open(inode, file);
55 if (err < 0)
56 return err;
57
58 card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL);
59 if (!card) {
60 err = -ENODEV;
61 goto __error1;
62 }
63 err = snd_card_file_add(card, file);
64 if (err < 0) {
65 err = -ENODEV;
66 goto __error1;
67 }
68 if (!try_module_get(card->module)) {
69 err = -EFAULT;
70 goto __error2;
71 }
72 ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
73 if (ctl == NULL) {
74 err = -ENOMEM;
75 goto __error;
76 }
77 INIT_LIST_HEAD(&ctl->events);
78 init_waitqueue_head(&ctl->change_sleep);
79 spin_lock_init(&ctl->read_lock);
80 ctl->card = card;
81 ctl->prefer_pcm_subdevice = -1;
82 ctl->prefer_rawmidi_subdevice = -1;
83 ctl->pid = get_pid(task_pid(current));
84 file->private_data = ctl;
85 write_lock_irqsave(&card->ctl_files_rwlock, flags);
86 list_add_tail(&ctl->list, &card->ctl_files);
87 write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
88 return 0;
89
90 __error:
91 module_put(card->module);
92 __error2:
93 snd_card_file_remove(card, file);
94 __error1:
95 return err;
96}
97
98static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl)
99{
100 unsigned long flags;
101 struct snd_kctl_event *cread;
102
103 spin_lock_irqsave(&ctl->read_lock, flags);
104 while (!list_empty(&ctl->events)) {
105 cread = snd_kctl_event(ctl->events.next);
106 list_del(&cread->list);
107 kfree(cread);
108 }
109 spin_unlock_irqrestore(&ctl->read_lock, flags);
110}
111
112static int snd_ctl_release(struct inode *inode, struct file *file)
113{
114 unsigned long flags;
115 struct snd_card *card;
116 struct snd_ctl_file *ctl;
117 struct snd_kcontrol *control;
118 unsigned int idx;
119
120 ctl = file->private_data;
121 file->private_data = NULL;
122 card = ctl->card;
123 write_lock_irqsave(&card->ctl_files_rwlock, flags);
124 list_del(&ctl->list);
125 write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
126 down_write(&card->controls_rwsem);
127 list_for_each_entry(control, &card->controls, list)
128 for (idx = 0; idx < control->count; idx++)
129 if (control->vd[idx].owner == ctl)
130 control->vd[idx].owner = NULL;
131 up_write(&card->controls_rwsem);
132 snd_ctl_empty_read_queue(ctl);
133 put_pid(ctl->pid);
134 kfree(ctl);
135 module_put(card->module);
136 snd_card_file_remove(card, file);
137 return 0;
138}
139
140void snd_ctl_notify(struct snd_card *card, unsigned int mask,
141 struct snd_ctl_elem_id *id)
142{
143 unsigned long flags;
144 struct snd_ctl_file *ctl;
145 struct snd_kctl_event *ev;
146
147 if (snd_BUG_ON(!card || !id))
148 return;
149 read_lock(&card->ctl_files_rwlock);
150#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
151 card->mixer_oss_change_count++;
152#endif
153 list_for_each_entry(ctl, &card->ctl_files, list) {
154 if (!ctl->subscribed)
155 continue;
156 spin_lock_irqsave(&ctl->read_lock, flags);
157 list_for_each_entry(ev, &ctl->events, list) {
158 if (ev->id.numid == id->numid) {
159 ev->mask |= mask;
160 goto _found;
161 }
162 }
163 ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
164 if (ev) {
165 ev->id = *id;
166 ev->mask = mask;
167 list_add_tail(&ev->list, &ctl->events);
168 } else {
169 snd_printk(KERN_ERR "No memory available to allocate event\n");
170 }
171 _found:
172 wake_up(&ctl->change_sleep);
173 spin_unlock_irqrestore(&ctl->read_lock, flags);
174 kill_fasync(&ctl->fasync, SIGIO, POLL_IN);
175 }
176 read_unlock(&card->ctl_files_rwlock);
177}
178
179EXPORT_SYMBOL(snd_ctl_notify);
180
181/**
182 * snd_ctl_new - create a control instance from the template
183 * @control: the control template
184 * @access: the default control access
185 *
186 * Allocates a new struct snd_kcontrol instance and copies the given template
187 * to the new instance. It does not copy volatile data (access).
188 *
189 * Returns the pointer of the new instance, or NULL on failure.
190 */
191static struct snd_kcontrol *snd_ctl_new(struct snd_kcontrol *control,
192 unsigned int access)
193{
194 struct snd_kcontrol *kctl;
195 unsigned int idx;
196
197 if (snd_BUG_ON(!control || !control->count))
198 return NULL;
199
200 if (control->count > MAX_CONTROL_COUNT)
201 return NULL;
202
203 kctl = kzalloc(sizeof(*kctl) + sizeof(struct snd_kcontrol_volatile) * control->count, GFP_KERNEL);
204 if (kctl == NULL) {
205 snd_printk(KERN_ERR "Cannot allocate control instance\n");
206 return NULL;
207 }
208 *kctl = *control;
209 for (idx = 0; idx < kctl->count; idx++)
210 kctl->vd[idx].access = access;
211 return kctl;
212}
213
214/**
215 * snd_ctl_new1 - create a control instance from the template
216 * @ncontrol: the initialization record
217 * @private_data: the private data to set
218 *
219 * Allocates a new struct snd_kcontrol instance and initialize from the given
220 * template. When the access field of ncontrol is 0, it's assumed as
221 * READWRITE access. When the count field is 0, it's assumes as one.
222 *
223 * Returns the pointer of the newly generated instance, or NULL on failure.
224 */
225struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
226 void *private_data)
227{
228 struct snd_kcontrol kctl;
229 unsigned int access;
230
231 if (snd_BUG_ON(!ncontrol || !ncontrol->info))
232 return NULL;
233 memset(&kctl, 0, sizeof(kctl));
234 kctl.id.iface = ncontrol->iface;
235 kctl.id.device = ncontrol->device;
236 kctl.id.subdevice = ncontrol->subdevice;
237 if (ncontrol->name) {
238 strlcpy(kctl.id.name, ncontrol->name, sizeof(kctl.id.name));
239 if (strcmp(ncontrol->name, kctl.id.name) != 0)
240 snd_printk(KERN_WARNING
241 "Control name '%s' truncated to '%s'\n",
242 ncontrol->name, kctl.id.name);
243 }
244 kctl.id.index = ncontrol->index;
245 kctl.count = ncontrol->count ? ncontrol->count : 1;
246 access = ncontrol->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
247 (ncontrol->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
248 SNDRV_CTL_ELEM_ACCESS_INACTIVE|
249 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE|
250 SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND|
251 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK));
252 kctl.info = ncontrol->info;
253 kctl.get = ncontrol->get;
254 kctl.put = ncontrol->put;
255 kctl.tlv.p = ncontrol->tlv.p;
256 kctl.private_value = ncontrol->private_value;
257 kctl.private_data = private_data;
258 return snd_ctl_new(&kctl, access);
259}
260
261EXPORT_SYMBOL(snd_ctl_new1);
262
263/**
264 * snd_ctl_free_one - release the control instance
265 * @kcontrol: the control instance
266 *
267 * Releases the control instance created via snd_ctl_new()
268 * or snd_ctl_new1().
269 * Don't call this after the control was added to the card.
270 */
271void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
272{
273 if (kcontrol) {
274 if (kcontrol->private_free)
275 kcontrol->private_free(kcontrol);
276 kfree(kcontrol);
277 }
278}
279
280EXPORT_SYMBOL(snd_ctl_free_one);
281
282static bool snd_ctl_remove_numid_conflict(struct snd_card *card,
283 unsigned int count)
284{
285 struct snd_kcontrol *kctl;
286
287 list_for_each_entry(kctl, &card->controls, list) {
288 if (kctl->id.numid < card->last_numid + 1 + count &&
289 kctl->id.numid + kctl->count > card->last_numid + 1) {
290 card->last_numid = kctl->id.numid + kctl->count - 1;
291 return true;
292 }
293 }
294 return false;
295}
296
297static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
298{
299 unsigned int iter = 100000;
300
301 while (snd_ctl_remove_numid_conflict(card, count)) {
302 if (--iter == 0) {
303 /* this situation is very unlikely */
304 snd_printk(KERN_ERR "unable to allocate new control numid\n");
305 return -ENOMEM;
306 }
307 }
308 return 0;
309}
310
311/**
312 * snd_ctl_add - add the control instance to the card
313 * @card: the card instance
314 * @kcontrol: the control instance to add
315 *
316 * Adds the control instance created via snd_ctl_new() or
317 * snd_ctl_new1() to the given card. Assigns also an unique
318 * numid used for fast search.
319 *
320 * Returns zero if successful, or a negative error code on failure.
321 *
322 * It frees automatically the control which cannot be added.
323 */
324int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
325{
326 struct snd_ctl_elem_id id;
327 unsigned int idx;
328 int err = -EINVAL;
329
330 if (! kcontrol)
331 return err;
332 if (snd_BUG_ON(!card || !kcontrol->info))
333 goto error;
334 id = kcontrol->id;
335 down_write(&card->controls_rwsem);
336 if (snd_ctl_find_id(card, &id)) {
337 up_write(&card->controls_rwsem);
338 snd_printd(KERN_ERR "control %i:%i:%i:%s:%i is already present\n",
339 id.iface,
340 id.device,
341 id.subdevice,
342 id.name,
343 id.index);
344 err = -EBUSY;
345 goto error;
346 }
347 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
348 up_write(&card->controls_rwsem);
349 err = -ENOMEM;
350 goto error;
351 }
352 list_add_tail(&kcontrol->list, &card->controls);
353 card->controls_count += kcontrol->count;
354 kcontrol->id.numid = card->last_numid + 1;
355 card->last_numid += kcontrol->count;
356 up_write(&card->controls_rwsem);
357 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
358 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
359 return 0;
360
361 error:
362 snd_ctl_free_one(kcontrol);
363 return err;
364}
365
366EXPORT_SYMBOL(snd_ctl_add);
367
368/**
369 * snd_ctl_replace - replace the control instance of the card
370 * @card: the card instance
371 * @kcontrol: the control instance to replace
372 * @add_on_replace: add the control if not already added
373 *
374 * Replaces the given control. If the given control does not exist
375 * and the add_on_replace flag is set, the control is added. If the
376 * control exists, it is destroyed first.
377 *
378 * Returns zero if successful, or a negative error code on failure.
379 *
380 * It frees automatically the control which cannot be added or replaced.
381 */
382int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol,
383 bool add_on_replace)
384{
385 struct snd_ctl_elem_id id;
386 unsigned int idx;
387 struct snd_kcontrol *old;
388 int ret;
389
390 if (!kcontrol)
391 return -EINVAL;
392 if (snd_BUG_ON(!card || !kcontrol->info)) {
393 ret = -EINVAL;
394 goto error;
395 }
396 id = kcontrol->id;
397 down_write(&card->controls_rwsem);
398 old = snd_ctl_find_id(card, &id);
399 if (!old) {
400 if (add_on_replace)
401 goto add;
402 up_write(&card->controls_rwsem);
403 ret = -EINVAL;
404 goto error;
405 }
406 ret = snd_ctl_remove(card, old);
407 if (ret < 0) {
408 up_write(&card->controls_rwsem);
409 goto error;
410 }
411add:
412 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
413 up_write(&card->controls_rwsem);
414 ret = -ENOMEM;
415 goto error;
416 }
417 list_add_tail(&kcontrol->list, &card->controls);
418 card->controls_count += kcontrol->count;
419 kcontrol->id.numid = card->last_numid + 1;
420 card->last_numid += kcontrol->count;
421 up_write(&card->controls_rwsem);
422 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
423 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
424 return 0;
425
426error:
427 snd_ctl_free_one(kcontrol);
428 return ret;
429}
430EXPORT_SYMBOL(snd_ctl_replace);
431
432/**
433 * snd_ctl_remove - remove the control from the card and release it
434 * @card: the card instance
435 * @kcontrol: the control instance to remove
436 *
437 * Removes the control from the card and then releases the instance.
438 * You don't need to call snd_ctl_free_one(). You must be in
439 * the write lock - down_write(&card->controls_rwsem).
440 *
441 * Returns 0 if successful, or a negative error code on failure.
442 */
443int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
444{
445 struct snd_ctl_elem_id id;
446 unsigned int idx;
447
448 if (snd_BUG_ON(!card || !kcontrol))
449 return -EINVAL;
450 list_del(&kcontrol->list);
451 card->controls_count -= kcontrol->count;
452 id = kcontrol->id;
453 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
454 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
455 snd_ctl_free_one(kcontrol);
456 return 0;
457}
458
459EXPORT_SYMBOL(snd_ctl_remove);
460
461/**
462 * snd_ctl_remove_id - remove the control of the given id and release it
463 * @card: the card instance
464 * @id: the control id to remove
465 *
466 * Finds the control instance with the given id, removes it from the
467 * card list and releases it.
468 *
469 * Returns 0 if successful, or a negative error code on failure.
470 */
471int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
472{
473 struct snd_kcontrol *kctl;
474 int ret;
475
476 down_write(&card->controls_rwsem);
477 kctl = snd_ctl_find_id(card, id);
478 if (kctl == NULL) {
479 up_write(&card->controls_rwsem);
480 return -ENOENT;
481 }
482 ret = snd_ctl_remove(card, kctl);
483 up_write(&card->controls_rwsem);
484 return ret;
485}
486
487EXPORT_SYMBOL(snd_ctl_remove_id);
488
489/**
490 * snd_ctl_remove_user_ctl - remove and release the unlocked user control
491 * @file: active control handle
492 * @id: the control id to remove
493 *
494 * Finds the control instance with the given id, removes it from the
495 * card list and releases it.
496 *
497 * Returns 0 if successful, or a negative error code on failure.
498 */
499static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
500 struct snd_ctl_elem_id *id)
501{
502 struct snd_card *card = file->card;
503 struct snd_kcontrol *kctl;
504 int idx, ret;
505
506 down_write(&card->controls_rwsem);
507 kctl = snd_ctl_find_id(card, id);
508 if (kctl == NULL) {
509 ret = -ENOENT;
510 goto error;
511 }
512 if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
513 ret = -EINVAL;
514 goto error;
515 }
516 for (idx = 0; idx < kctl->count; idx++)
517 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
518 ret = -EBUSY;
519 goto error;
520 }
521 ret = snd_ctl_remove(card, kctl);
522 if (ret < 0)
523 goto error;
524 card->user_ctl_count--;
525error:
526 up_write(&card->controls_rwsem);
527 return ret;
528}
529
530/**
531 * snd_ctl_activate_id - activate/inactivate the control of the given id
532 * @card: the card instance
533 * @id: the control id to activate/inactivate
534 * @active: non-zero to activate
535 *
536 * Finds the control instance with the given id, and activate or
537 * inactivate the control together with notification, if changed.
538 *
539 * Returns 0 if unchanged, 1 if changed, or a negative error code on failure.
540 */
541int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
542 int active)
543{
544 struct snd_kcontrol *kctl;
545 struct snd_kcontrol_volatile *vd;
546 unsigned int index_offset;
547 int ret;
548
549 down_write(&card->controls_rwsem);
550 kctl = snd_ctl_find_id(card, id);
551 if (kctl == NULL) {
552 ret = -ENOENT;
553 goto unlock;
554 }
555 index_offset = snd_ctl_get_ioff(kctl, &kctl->id);
556 vd = &kctl->vd[index_offset];
557 ret = 0;
558 if (active) {
559 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE))
560 goto unlock;
561 vd->access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
562 } else {
563 if (vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE)
564 goto unlock;
565 vd->access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE;
566 }
567 ret = 1;
568 unlock:
569 up_write(&card->controls_rwsem);
570 if (ret > 0)
571 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, id);
572 return ret;
573}
574EXPORT_SYMBOL_GPL(snd_ctl_activate_id);
575
576/**
577 * snd_ctl_rename_id - replace the id of a control on the card
578 * @card: the card instance
579 * @src_id: the old id
580 * @dst_id: the new id
581 *
582 * Finds the control with the old id from the card, and replaces the
583 * id with the new one.
584 *
585 * Returns zero if successful, or a negative error code on failure.
586 */
587int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
588 struct snd_ctl_elem_id *dst_id)
589{
590 struct snd_kcontrol *kctl;
591
592 down_write(&card->controls_rwsem);
593 kctl = snd_ctl_find_id(card, src_id);
594 if (kctl == NULL) {
595 up_write(&card->controls_rwsem);
596 return -ENOENT;
597 }
598 kctl->id = *dst_id;
599 kctl->id.numid = card->last_numid + 1;
600 card->last_numid += kctl->count;
601 up_write(&card->controls_rwsem);
602 return 0;
603}
604
605EXPORT_SYMBOL(snd_ctl_rename_id);
606
607/**
608 * snd_ctl_find_numid - find the control instance with the given number-id
609 * @card: the card instance
610 * @numid: the number-id to search
611 *
612 * Finds the control instance with the given number-id from the card.
613 *
614 * Returns the pointer of the instance if found, or NULL if not.
615 *
616 * The caller must down card->controls_rwsem before calling this function
617 * (if the race condition can happen).
618 */
619struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid)
620{
621 struct snd_kcontrol *kctl;
622
623 if (snd_BUG_ON(!card || !numid))
624 return NULL;
625 list_for_each_entry(kctl, &card->controls, list) {
626 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
627 return kctl;
628 }
629 return NULL;
630}
631
632EXPORT_SYMBOL(snd_ctl_find_numid);
633
634/**
635 * snd_ctl_find_id - find the control instance with the given id
636 * @card: the card instance
637 * @id: the id to search
638 *
639 * Finds the control instance with the given id from the card.
640 *
641 * Returns the pointer of the instance if found, or NULL if not.
642 *
643 * The caller must down card->controls_rwsem before calling this function
644 * (if the race condition can happen).
645 */
646struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
647 struct snd_ctl_elem_id *id)
648{
649 struct snd_kcontrol *kctl;
650
651 if (snd_BUG_ON(!card || !id))
652 return NULL;
653 if (id->numid != 0)
654 return snd_ctl_find_numid(card, id->numid);
655 list_for_each_entry(kctl, &card->controls, list) {
656 if (kctl->id.iface != id->iface)
657 continue;
658 if (kctl->id.device != id->device)
659 continue;
660 if (kctl->id.subdevice != id->subdevice)
661 continue;
662 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
663 continue;
664 if (kctl->id.index > id->index)
665 continue;
666 if (kctl->id.index + kctl->count <= id->index)
667 continue;
668 return kctl;
669 }
670 return NULL;
671}
672
673EXPORT_SYMBOL(snd_ctl_find_id);
674
675static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
676 unsigned int cmd, void __user *arg)
677{
678 struct snd_ctl_card_info *info;
679
680 info = kzalloc(sizeof(*info), GFP_KERNEL);
681 if (! info)
682 return -ENOMEM;
683 down_read(&snd_ioctl_rwsem);
684 info->card = card->number;
685 strlcpy(info->id, card->id, sizeof(info->id));
686 strlcpy(info->driver, card->driver, sizeof(info->driver));
687 strlcpy(info->name, card->shortname, sizeof(info->name));
688 strlcpy(info->longname, card->longname, sizeof(info->longname));
689 strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
690 strlcpy(info->components, card->components, sizeof(info->components));
691 up_read(&snd_ioctl_rwsem);
692 if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
693 kfree(info);
694 return -EFAULT;
695 }
696 kfree(info);
697 return 0;
698}
699
700static int snd_ctl_elem_list(struct snd_card *card,
701 struct snd_ctl_elem_list __user *_list)
702{
703 struct list_head *plist;
704 struct snd_ctl_elem_list list;
705 struct snd_kcontrol *kctl;
706 struct snd_ctl_elem_id *dst, *id;
707 unsigned int offset, space, jidx;
708
709 if (copy_from_user(&list, _list, sizeof(list)))
710 return -EFAULT;
711 offset = list.offset;
712 space = list.space;
713 /* try limit maximum space */
714 if (space > 16384)
715 return -ENOMEM;
716 if (space > 0) {
717 /* allocate temporary buffer for atomic operation */
718 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
719 if (dst == NULL)
720 return -ENOMEM;
721 down_read(&card->controls_rwsem);
722 list.count = card->controls_count;
723 plist = card->controls.next;
724 while (plist != &card->controls) {
725 if (offset == 0)
726 break;
727 kctl = snd_kcontrol(plist);
728 if (offset < kctl->count)
729 break;
730 offset -= kctl->count;
731 plist = plist->next;
732 }
733 list.used = 0;
734 id = dst;
735 while (space > 0 && plist != &card->controls) {
736 kctl = snd_kcontrol(plist);
737 for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
738 snd_ctl_build_ioff(id, kctl, jidx);
739 id++;
740 space--;
741 list.used++;
742 }
743 plist = plist->next;
744 offset = 0;
745 }
746 up_read(&card->controls_rwsem);
747 if (list.used > 0 &&
748 copy_to_user(list.pids, dst,
749 list.used * sizeof(struct snd_ctl_elem_id))) {
750 vfree(dst);
751 return -EFAULT;
752 }
753 vfree(dst);
754 } else {
755 down_read(&card->controls_rwsem);
756 list.count = card->controls_count;
757 up_read(&card->controls_rwsem);
758 }
759 if (copy_to_user(_list, &list, sizeof(list)))
760 return -EFAULT;
761 return 0;
762}
763
764static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
765 struct snd_ctl_elem_info *info)
766{
767 struct snd_card *card = ctl->card;
768 struct snd_kcontrol *kctl;
769 struct snd_kcontrol_volatile *vd;
770 unsigned int index_offset;
771 int result;
772
773 down_read(&card->controls_rwsem);
774 kctl = snd_ctl_find_id(card, &info->id);
775 if (kctl == NULL) {
776 up_read(&card->controls_rwsem);
777 return -ENOENT;
778 }
779#ifdef CONFIG_SND_DEBUG
780 info->access = 0;
781#endif
782 result = kctl->info(kctl, info);
783 if (result >= 0) {
784 snd_BUG_ON(info->access);
785 index_offset = snd_ctl_get_ioff(kctl, &info->id);
786 vd = &kctl->vd[index_offset];
787 snd_ctl_build_ioff(&info->id, kctl, index_offset);
788 info->access = vd->access;
789 if (vd->owner) {
790 info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
791 if (vd->owner == ctl)
792 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
793 info->owner = pid_vnr(vd->owner->pid);
794 } else {
795 info->owner = -1;
796 }
797 }
798 up_read(&card->controls_rwsem);
799 return result;
800}
801
802static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
803 struct snd_ctl_elem_info __user *_info)
804{
805 struct snd_ctl_elem_info info;
806 int result;
807
808 if (copy_from_user(&info, _info, sizeof(info)))
809 return -EFAULT;
810 snd_power_lock(ctl->card);
811 result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
812 if (result >= 0)
813 result = snd_ctl_elem_info(ctl, &info);
814 snd_power_unlock(ctl->card);
815 if (result >= 0)
816 if (copy_to_user(_info, &info, sizeof(info)))
817 return -EFAULT;
818 return result;
819}
820
821static int snd_ctl_elem_read(struct snd_card *card,
822 struct snd_ctl_elem_value *control)
823{
824 struct snd_kcontrol *kctl;
825 struct snd_kcontrol_volatile *vd;
826 unsigned int index_offset;
827 int result;
828
829 down_read(&card->controls_rwsem);
830 kctl = snd_ctl_find_id(card, &control->id);
831 if (kctl == NULL) {
832 result = -ENOENT;
833 } else {
834 index_offset = snd_ctl_get_ioff(kctl, &control->id);
835 vd = &kctl->vd[index_offset];
836 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
837 kctl->get != NULL) {
838 snd_ctl_build_ioff(&control->id, kctl, index_offset);
839 result = kctl->get(kctl, control);
840 } else
841 result = -EPERM;
842 }
843 up_read(&card->controls_rwsem);
844 return result;
845}
846
847static int snd_ctl_elem_read_user(struct snd_card *card,
848 struct snd_ctl_elem_value __user *_control)
849{
850 struct snd_ctl_elem_value *control;
851 int result;
852
853 control = memdup_user(_control, sizeof(*control));
854 if (IS_ERR(control))
855 return PTR_ERR(control);
856
857 snd_power_lock(card);
858 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
859 if (result >= 0)
860 result = snd_ctl_elem_read(card, control);
861 snd_power_unlock(card);
862 if (result >= 0)
863 if (copy_to_user(_control, control, sizeof(*control)))
864 result = -EFAULT;
865 kfree(control);
866 return result;
867}
868
869static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
870 struct snd_ctl_elem_value *control)
871{
872 struct snd_kcontrol *kctl;
873 struct snd_kcontrol_volatile *vd;
874 unsigned int index_offset;
875 int result;
876
877 down_read(&card->controls_rwsem);
878 kctl = snd_ctl_find_id(card, &control->id);
879 if (kctl == NULL) {
880 result = -ENOENT;
881 } else {
882 index_offset = snd_ctl_get_ioff(kctl, &control->id);
883 vd = &kctl->vd[index_offset];
884 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
885 kctl->put == NULL ||
886 (file && vd->owner && vd->owner != file)) {
887 result = -EPERM;
888 } else {
889 snd_ctl_build_ioff(&control->id, kctl, index_offset);
890 result = kctl->put(kctl, control);
891 }
892 if (result > 0) {
893 up_read(&card->controls_rwsem);
894 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
895 &control->id);
896 return 0;
897 }
898 }
899 up_read(&card->controls_rwsem);
900 return result;
901}
902
903static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
904 struct snd_ctl_elem_value __user *_control)
905{
906 struct snd_ctl_elem_value *control;
907 struct snd_card *card;
908 int result;
909
910 control = memdup_user(_control, sizeof(*control));
911 if (IS_ERR(control))
912 return PTR_ERR(control);
913
914 card = file->card;
915 snd_power_lock(card);
916 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
917 if (result >= 0)
918 result = snd_ctl_elem_write(card, file, control);
919 snd_power_unlock(card);
920 if (result >= 0)
921 if (copy_to_user(_control, control, sizeof(*control)))
922 result = -EFAULT;
923 kfree(control);
924 return result;
925}
926
927static int snd_ctl_elem_lock(struct snd_ctl_file *file,
928 struct snd_ctl_elem_id __user *_id)
929{
930 struct snd_card *card = file->card;
931 struct snd_ctl_elem_id id;
932 struct snd_kcontrol *kctl;
933 struct snd_kcontrol_volatile *vd;
934 int result;
935
936 if (copy_from_user(&id, _id, sizeof(id)))
937 return -EFAULT;
938 down_write(&card->controls_rwsem);
939 kctl = snd_ctl_find_id(card, &id);
940 if (kctl == NULL) {
941 result = -ENOENT;
942 } else {
943 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
944 if (vd->owner != NULL)
945 result = -EBUSY;
946 else {
947 vd->owner = file;
948 result = 0;
949 }
950 }
951 up_write(&card->controls_rwsem);
952 return result;
953}
954
955static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
956 struct snd_ctl_elem_id __user *_id)
957{
958 struct snd_card *card = file->card;
959 struct snd_ctl_elem_id id;
960 struct snd_kcontrol *kctl;
961 struct snd_kcontrol_volatile *vd;
962 int result;
963
964 if (copy_from_user(&id, _id, sizeof(id)))
965 return -EFAULT;
966 down_write(&card->controls_rwsem);
967 kctl = snd_ctl_find_id(card, &id);
968 if (kctl == NULL) {
969 result = -ENOENT;
970 } else {
971 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
972 if (vd->owner == NULL)
973 result = -EINVAL;
974 else if (vd->owner != file)
975 result = -EPERM;
976 else {
977 vd->owner = NULL;
978 result = 0;
979 }
980 }
981 up_write(&card->controls_rwsem);
982 return result;
983}
984
985struct user_element {
986 struct snd_ctl_elem_info info;
987 void *elem_data; /* element data */
988 unsigned long elem_data_size; /* size of element data in bytes */
989 void *tlv_data; /* TLV data */
990 unsigned long tlv_data_size; /* TLV data size */
991 void *priv_data; /* private data (like strings for enumerated type) */
992 unsigned long priv_data_size; /* size of private data in bytes */
993};
994
995static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
996 struct snd_ctl_elem_info *uinfo)
997{
998 struct user_element *ue = kcontrol->private_data;
999
1000 *uinfo = ue->info;
1001 return 0;
1002}
1003
1004static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
1005 struct snd_ctl_elem_value *ucontrol)
1006{
1007 struct user_element *ue = kcontrol->private_data;
1008
1009 memcpy(&ucontrol->value, ue->elem_data, ue->elem_data_size);
1010 return 0;
1011}
1012
1013static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
1014 struct snd_ctl_elem_value *ucontrol)
1015{
1016 int change;
1017 struct user_element *ue = kcontrol->private_data;
1018
1019 change = memcmp(&ucontrol->value, ue->elem_data, ue->elem_data_size) != 0;
1020 if (change)
1021 memcpy(ue->elem_data, &ucontrol->value, ue->elem_data_size);
1022 return change;
1023}
1024
1025static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
1026 int op_flag,
1027 unsigned int size,
1028 unsigned int __user *tlv)
1029{
1030 struct user_element *ue = kcontrol->private_data;
1031 int change = 0;
1032 void *new_data;
1033
1034 if (op_flag > 0) {
1035 if (size > 1024 * 128) /* sane value */
1036 return -EINVAL;
1037
1038 new_data = memdup_user(tlv, size);
1039 if (IS_ERR(new_data))
1040 return PTR_ERR(new_data);
1041 change = ue->tlv_data_size != size;
1042 if (!change)
1043 change = memcmp(ue->tlv_data, new_data, size);
1044 kfree(ue->tlv_data);
1045 ue->tlv_data = new_data;
1046 ue->tlv_data_size = size;
1047 } else {
1048 if (! ue->tlv_data_size || ! ue->tlv_data)
1049 return -ENXIO;
1050 if (size < ue->tlv_data_size)
1051 return -ENOSPC;
1052 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
1053 return -EFAULT;
1054 }
1055 return change;
1056}
1057
1058static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
1059{
1060 struct user_element *ue = kcontrol->private_data;
1061 if (ue->tlv_data)
1062 kfree(ue->tlv_data);
1063 kfree(ue);
1064}
1065
1066static int snd_ctl_elem_add(struct snd_ctl_file *file,
1067 struct snd_ctl_elem_info *info, int replace)
1068{
1069 struct snd_card *card = file->card;
1070 struct snd_kcontrol kctl, *_kctl;
1071 unsigned int access;
1072 long private_size;
1073 struct user_element *ue;
1074 int idx, err;
1075
1076 if (card->user_ctl_count >= MAX_USER_CONTROLS)
1077 return -ENOMEM;
1078 if (info->count < 1)
1079 return -EINVAL;
1080 access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
1081 (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
1082 SNDRV_CTL_ELEM_ACCESS_INACTIVE|
1083 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE));
1084 info->id.numid = 0;
1085 memset(&kctl, 0, sizeof(kctl));
1086 down_write(&card->controls_rwsem);
1087 _kctl = snd_ctl_find_id(card, &info->id);
1088 err = 0;
1089 if (_kctl) {
1090 if (replace)
1091 err = snd_ctl_remove(card, _kctl);
1092 else
1093 err = -EBUSY;
1094 } else {
1095 if (replace)
1096 err = -ENOENT;
1097 }
1098 up_write(&card->controls_rwsem);
1099 if (err < 0)
1100 return err;
1101 memcpy(&kctl.id, &info->id, sizeof(info->id));
1102 kctl.count = info->owner ? info->owner : 1;
1103 access |= SNDRV_CTL_ELEM_ACCESS_USER;
1104 kctl.info = snd_ctl_elem_user_info;
1105 if (access & SNDRV_CTL_ELEM_ACCESS_READ)
1106 kctl.get = snd_ctl_elem_user_get;
1107 if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
1108 kctl.put = snd_ctl_elem_user_put;
1109 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
1110 kctl.tlv.c = snd_ctl_elem_user_tlv;
1111 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1112 }
1113 switch (info->type) {
1114 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
1115 case SNDRV_CTL_ELEM_TYPE_INTEGER:
1116 private_size = sizeof(long);
1117 if (info->count > 128)
1118 return -EINVAL;
1119 break;
1120 case SNDRV_CTL_ELEM_TYPE_INTEGER64:
1121 private_size = sizeof(long long);
1122 if (info->count > 64)
1123 return -EINVAL;
1124 break;
1125 case SNDRV_CTL_ELEM_TYPE_BYTES:
1126 private_size = sizeof(unsigned char);
1127 if (info->count > 512)
1128 return -EINVAL;
1129 break;
1130 case SNDRV_CTL_ELEM_TYPE_IEC958:
1131 private_size = sizeof(struct snd_aes_iec958);
1132 if (info->count != 1)
1133 return -EINVAL;
1134 break;
1135 default:
1136 return -EINVAL;
1137 }
1138 private_size *= info->count;
1139 ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);
1140 if (ue == NULL)
1141 return -ENOMEM;
1142 ue->info = *info;
1143 ue->info.access = 0;
1144 ue->elem_data = (char *)ue + sizeof(*ue);
1145 ue->elem_data_size = private_size;
1146 kctl.private_free = snd_ctl_elem_user_free;
1147 _kctl = snd_ctl_new(&kctl, access);
1148 if (_kctl == NULL) {
1149 kfree(ue);
1150 return -ENOMEM;
1151 }
1152 _kctl->private_data = ue;
1153 for (idx = 0; idx < _kctl->count; idx++)
1154 _kctl->vd[idx].owner = file;
1155 err = snd_ctl_add(card, _kctl);
1156 if (err < 0)
1157 return err;
1158
1159 down_write(&card->controls_rwsem);
1160 card->user_ctl_count++;
1161 up_write(&card->controls_rwsem);
1162
1163 return 0;
1164}
1165
1166static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1167 struct snd_ctl_elem_info __user *_info, int replace)
1168{
1169 struct snd_ctl_elem_info info;
1170 if (copy_from_user(&info, _info, sizeof(info)))
1171 return -EFAULT;
1172 return snd_ctl_elem_add(file, &info, replace);
1173}
1174
1175static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1176 struct snd_ctl_elem_id __user *_id)
1177{
1178 struct snd_ctl_elem_id id;
1179
1180 if (copy_from_user(&id, _id, sizeof(id)))
1181 return -EFAULT;
1182 return snd_ctl_remove_user_ctl(file, &id);
1183}
1184
1185static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
1186{
1187 int subscribe;
1188 if (get_user(subscribe, ptr))
1189 return -EFAULT;
1190 if (subscribe < 0) {
1191 subscribe = file->subscribed;
1192 if (put_user(subscribe, ptr))
1193 return -EFAULT;
1194 return 0;
1195 }
1196 if (subscribe) {
1197 file->subscribed = 1;
1198 return 0;
1199 } else if (file->subscribed) {
1200 snd_ctl_empty_read_queue(file);
1201 file->subscribed = 0;
1202 }
1203 return 0;
1204}
1205
1206static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1207 struct snd_ctl_tlv __user *_tlv,
1208 int op_flag)
1209{
1210 struct snd_card *card = file->card;
1211 struct snd_ctl_tlv tlv;
1212 struct snd_kcontrol *kctl;
1213 struct snd_kcontrol_volatile *vd;
1214 unsigned int len;
1215 int err = 0;
1216
1217 if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1218 return -EFAULT;
1219 if (tlv.length < sizeof(unsigned int) * 2)
1220 return -EINVAL;
1221 down_read(&card->controls_rwsem);
1222 kctl = snd_ctl_find_numid(card, tlv.numid);
1223 if (kctl == NULL) {
1224 err = -ENOENT;
1225 goto __kctl_end;
1226 }
1227 if (kctl->tlv.p == NULL) {
1228 err = -ENXIO;
1229 goto __kctl_end;
1230 }
1231 vd = &kctl->vd[tlv.numid - kctl->id.numid];
1232 if ((op_flag == 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1233 (op_flag > 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1234 (op_flag < 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
1235 err = -ENXIO;
1236 goto __kctl_end;
1237 }
1238 if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
1239 if (vd->owner != NULL && vd->owner != file) {
1240 err = -EPERM;
1241 goto __kctl_end;
1242 }
1243 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv);
1244 if (err > 0) {
1245 up_read(&card->controls_rwsem);
1246 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &kctl->id);
1247 return 0;
1248 }
1249 } else {
1250 if (op_flag) {
1251 err = -ENXIO;
1252 goto __kctl_end;
1253 }
1254 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1255 if (tlv.length < len) {
1256 err = -ENOMEM;
1257 goto __kctl_end;
1258 }
1259 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1260 err = -EFAULT;
1261 }
1262 __kctl_end:
1263 up_read(&card->controls_rwsem);
1264 return err;
1265}
1266
1267static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1268{
1269 struct snd_ctl_file *ctl;
1270 struct snd_card *card;
1271 struct snd_kctl_ioctl *p;
1272 void __user *argp = (void __user *)arg;
1273 int __user *ip = argp;
1274 int err;
1275
1276 ctl = file->private_data;
1277 card = ctl->card;
1278 if (snd_BUG_ON(!card))
1279 return -ENXIO;
1280 switch (cmd) {
1281 case SNDRV_CTL_IOCTL_PVERSION:
1282 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1283 case SNDRV_CTL_IOCTL_CARD_INFO:
1284 return snd_ctl_card_info(card, ctl, cmd, argp);
1285 case SNDRV_CTL_IOCTL_ELEM_LIST:
1286 return snd_ctl_elem_list(card, argp);
1287 case SNDRV_CTL_IOCTL_ELEM_INFO:
1288 return snd_ctl_elem_info_user(ctl, argp);
1289 case SNDRV_CTL_IOCTL_ELEM_READ:
1290 return snd_ctl_elem_read_user(card, argp);
1291 case SNDRV_CTL_IOCTL_ELEM_WRITE:
1292 return snd_ctl_elem_write_user(ctl, argp);
1293 case SNDRV_CTL_IOCTL_ELEM_LOCK:
1294 return snd_ctl_elem_lock(ctl, argp);
1295 case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1296 return snd_ctl_elem_unlock(ctl, argp);
1297 case SNDRV_CTL_IOCTL_ELEM_ADD:
1298 return snd_ctl_elem_add_user(ctl, argp, 0);
1299 case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1300 return snd_ctl_elem_add_user(ctl, argp, 1);
1301 case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1302 return snd_ctl_elem_remove(ctl, argp);
1303 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1304 return snd_ctl_subscribe_events(ctl, ip);
1305 case SNDRV_CTL_IOCTL_TLV_READ:
1306 return snd_ctl_tlv_ioctl(ctl, argp, 0);
1307 case SNDRV_CTL_IOCTL_TLV_WRITE:
1308 return snd_ctl_tlv_ioctl(ctl, argp, 1);
1309 case SNDRV_CTL_IOCTL_TLV_COMMAND:
1310 return snd_ctl_tlv_ioctl(ctl, argp, -1);
1311 case SNDRV_CTL_IOCTL_POWER:
1312 return -ENOPROTOOPT;
1313 case SNDRV_CTL_IOCTL_POWER_STATE:
1314#ifdef CONFIG_PM
1315 return put_user(card->power_state, ip) ? -EFAULT : 0;
1316#else
1317 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1318#endif
1319 }
1320 down_read(&snd_ioctl_rwsem);
1321 list_for_each_entry(p, &snd_control_ioctls, list) {
1322 err = p->fioctl(card, ctl, cmd, arg);
1323 if (err != -ENOIOCTLCMD) {
1324 up_read(&snd_ioctl_rwsem);
1325 return err;
1326 }
1327 }
1328 up_read(&snd_ioctl_rwsem);
1329 snd_printdd("unknown ioctl = 0x%x\n", cmd);
1330 return -ENOTTY;
1331}
1332
1333static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1334 size_t count, loff_t * offset)
1335{
1336 struct snd_ctl_file *ctl;
1337 int err = 0;
1338 ssize_t result = 0;
1339
1340 ctl = file->private_data;
1341 if (snd_BUG_ON(!ctl || !ctl->card))
1342 return -ENXIO;
1343 if (!ctl->subscribed)
1344 return -EBADFD;
1345 if (count < sizeof(struct snd_ctl_event))
1346 return -EINVAL;
1347 spin_lock_irq(&ctl->read_lock);
1348 while (count >= sizeof(struct snd_ctl_event)) {
1349 struct snd_ctl_event ev;
1350 struct snd_kctl_event *kev;
1351 while (list_empty(&ctl->events)) {
1352 wait_queue_t wait;
1353 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1354 err = -EAGAIN;
1355 goto __end_lock;
1356 }
1357 init_waitqueue_entry(&wait, current);
1358 add_wait_queue(&ctl->change_sleep, &wait);
1359 set_current_state(TASK_INTERRUPTIBLE);
1360 spin_unlock_irq(&ctl->read_lock);
1361 schedule();
1362 remove_wait_queue(&ctl->change_sleep, &wait);
1363 if (signal_pending(current))
1364 return -ERESTARTSYS;
1365 spin_lock_irq(&ctl->read_lock);
1366 }
1367 kev = snd_kctl_event(ctl->events.next);
1368 ev.type = SNDRV_CTL_EVENT_ELEM;
1369 ev.data.elem.mask = kev->mask;
1370 ev.data.elem.id = kev->id;
1371 list_del(&kev->list);
1372 spin_unlock_irq(&ctl->read_lock);
1373 kfree(kev);
1374 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
1375 err = -EFAULT;
1376 goto __end;
1377 }
1378 spin_lock_irq(&ctl->read_lock);
1379 buffer += sizeof(struct snd_ctl_event);
1380 count -= sizeof(struct snd_ctl_event);
1381 result += sizeof(struct snd_ctl_event);
1382 }
1383 __end_lock:
1384 spin_unlock_irq(&ctl->read_lock);
1385 __end:
1386 return result > 0 ? result : err;
1387}
1388
1389static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1390{
1391 unsigned int mask;
1392 struct snd_ctl_file *ctl;
1393
1394 ctl = file->private_data;
1395 if (!ctl->subscribed)
1396 return 0;
1397 poll_wait(file, &ctl->change_sleep, wait);
1398
1399 mask = 0;
1400 if (!list_empty(&ctl->events))
1401 mask |= POLLIN | POLLRDNORM;
1402
1403 return mask;
1404}
1405
1406/*
1407 * register the device-specific control-ioctls.
1408 * called from each device manager like pcm.c, hwdep.c, etc.
1409 */
1410static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1411{
1412 struct snd_kctl_ioctl *pn;
1413
1414 pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
1415 if (pn == NULL)
1416 return -ENOMEM;
1417 pn->fioctl = fcn;
1418 down_write(&snd_ioctl_rwsem);
1419 list_add_tail(&pn->list, lists);
1420 up_write(&snd_ioctl_rwsem);
1421 return 0;
1422}
1423
1424int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1425{
1426 return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1427}
1428
1429EXPORT_SYMBOL(snd_ctl_register_ioctl);
1430
1431#ifdef CONFIG_COMPAT
1432int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1433{
1434 return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1435}
1436
1437EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
1438#endif
1439
1440/*
1441 * de-register the device-specific control-ioctls.
1442 */
1443static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1444 struct list_head *lists)
1445{
1446 struct snd_kctl_ioctl *p;
1447
1448 if (snd_BUG_ON(!fcn))
1449 return -EINVAL;
1450 down_write(&snd_ioctl_rwsem);
1451 list_for_each_entry(p, lists, list) {
1452 if (p->fioctl == fcn) {
1453 list_del(&p->list);
1454 up_write(&snd_ioctl_rwsem);
1455 kfree(p);
1456 return 0;
1457 }
1458 }
1459 up_write(&snd_ioctl_rwsem);
1460 snd_BUG();
1461 return -EINVAL;
1462}
1463
1464int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1465{
1466 return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1467}
1468
1469EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1470
1471#ifdef CONFIG_COMPAT
1472int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1473{
1474 return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1475}
1476
1477EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
1478#endif
1479
1480static int snd_ctl_fasync(int fd, struct file * file, int on)
1481{
1482 struct snd_ctl_file *ctl;
1483
1484 ctl = file->private_data;
1485 return fasync_helper(fd, file, on, &ctl->fasync);
1486}
1487
1488/*
1489 * ioctl32 compat
1490 */
1491#ifdef CONFIG_COMPAT
1492#include "control_compat.c"
1493#else
1494#define snd_ctl_ioctl_compat NULL
1495#endif
1496
1497/*
1498 * INIT PART
1499 */
1500
1501static const struct file_operations snd_ctl_f_ops =
1502{
1503 .owner = THIS_MODULE,
1504 .read = snd_ctl_read,
1505 .open = snd_ctl_open,
1506 .release = snd_ctl_release,
1507 .llseek = no_llseek,
1508 .poll = snd_ctl_poll,
1509 .unlocked_ioctl = snd_ctl_ioctl,
1510 .compat_ioctl = snd_ctl_ioctl_compat,
1511 .fasync = snd_ctl_fasync,
1512};
1513
1514/*
1515 * registration of the control device
1516 */
1517static int snd_ctl_dev_register(struct snd_device *device)
1518{
1519 struct snd_card *card = device->device_data;
1520 int err, cardnum;
1521 char name[16];
1522
1523 if (snd_BUG_ON(!card))
1524 return -ENXIO;
1525 cardnum = card->number;
1526 if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1527 return -ENXIO;
1528 sprintf(name, "controlC%i", cardnum);
1529 if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1530 &snd_ctl_f_ops, card, name)) < 0)
1531 return err;
1532 return 0;
1533}
1534
1535/*
1536 * disconnection of the control device
1537 */
1538static int snd_ctl_dev_disconnect(struct snd_device *device)
1539{
1540 struct snd_card *card = device->device_data;
1541 struct snd_ctl_file *ctl;
1542 int err, cardnum;
1543
1544 if (snd_BUG_ON(!card))
1545 return -ENXIO;
1546 cardnum = card->number;
1547 if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1548 return -ENXIO;
1549
1550 read_lock(&card->ctl_files_rwlock);
1551 list_for_each_entry(ctl, &card->ctl_files, list) {
1552 wake_up(&ctl->change_sleep);
1553 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1554 }
1555 read_unlock(&card->ctl_files_rwlock);
1556
1557 if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
1558 card, -1)) < 0)
1559 return err;
1560 return 0;
1561}
1562
1563/*
1564 * free all controls
1565 */
1566static int snd_ctl_dev_free(struct snd_device *device)
1567{
1568 struct snd_card *card = device->device_data;
1569 struct snd_kcontrol *control;
1570
1571 down_write(&card->controls_rwsem);
1572 while (!list_empty(&card->controls)) {
1573 control = snd_kcontrol(card->controls.next);
1574 snd_ctl_remove(card, control);
1575 }
1576 up_write(&card->controls_rwsem);
1577 return 0;
1578}
1579
1580/*
1581 * create control core:
1582 * called from init.c
1583 */
1584int snd_ctl_create(struct snd_card *card)
1585{
1586 static struct snd_device_ops ops = {
1587 .dev_free = snd_ctl_dev_free,
1588 .dev_register = snd_ctl_dev_register,
1589 .dev_disconnect = snd_ctl_dev_disconnect,
1590 };
1591
1592 if (snd_BUG_ON(!card))
1593 return -ENXIO;
1594 return snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1595}
1596
1597/*
1598 * Frequently used control callbacks/helpers
1599 */
1600int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1601 struct snd_ctl_elem_info *uinfo)
1602{
1603 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1604 uinfo->count = 1;
1605 uinfo->value.integer.min = 0;
1606 uinfo->value.integer.max = 1;
1607 return 0;
1608}
1609
1610EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1611
1612int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1613 struct snd_ctl_elem_info *uinfo)
1614{
1615 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1616 uinfo->count = 2;
1617 uinfo->value.integer.min = 0;
1618 uinfo->value.integer.max = 1;
1619 return 0;
1620}
1621
1622EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);
1623
1624/**
1625 * snd_ctl_enum_info - fills the info structure for an enumerated control
1626 * @info: the structure to be filled
1627 * @channels: the number of the control's channels; often one
1628 * @items: the number of control values; also the size of @names
1629 * @names: an array containing the names of all control values
1630 *
1631 * Sets all required fields in @info to their appropriate values.
1632 * If the control's accessibility is not the default (readable and writable),
1633 * the caller has to fill @info->access.
1634 */
1635int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
1636 unsigned int items, const char *const names[])
1637{
1638 info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
1639 info->count = channels;
1640 info->value.enumerated.items = items;
1641 if (info->value.enumerated.item >= items)
1642 info->value.enumerated.item = items - 1;
1643 strlcpy(info->value.enumerated.name,
1644 names[info->value.enumerated.item],
1645 sizeof(info->value.enumerated.name));
1646 return 0;
1647}
1648EXPORT_SYMBOL(snd_ctl_enum_info);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Routines for driver control interface
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 */
6
7#include <linux/threads.h>
8#include <linux/interrupt.h>
9#include <linux/module.h>
10#include <linux/moduleparam.h>
11#include <linux/slab.h>
12#include <linux/vmalloc.h>
13#include <linux/time.h>
14#include <linux/mm.h>
15#include <linux/math64.h>
16#include <linux/sched/signal.h>
17#include <sound/core.h>
18#include <sound/minors.h>
19#include <sound/info.h>
20#include <sound/control.h>
21
22// Max allocation size for user controls.
23static int max_user_ctl_alloc_size = 8 * 1024 * 1024;
24module_param_named(max_user_ctl_alloc_size, max_user_ctl_alloc_size, int, 0444);
25MODULE_PARM_DESC(max_user_ctl_alloc_size, "Max allocation size for user controls");
26
27#define MAX_CONTROL_COUNT 1028
28
29struct snd_kctl_ioctl {
30 struct list_head list; /* list of all ioctls */
31 snd_kctl_ioctl_func_t fioctl;
32};
33
34static DECLARE_RWSEM(snd_ioctl_rwsem);
35static DECLARE_RWSEM(snd_ctl_layer_rwsem);
36static LIST_HEAD(snd_control_ioctls);
37#ifdef CONFIG_COMPAT
38static LIST_HEAD(snd_control_compat_ioctls);
39#endif
40static struct snd_ctl_layer_ops *snd_ctl_layer;
41
42static int snd_ctl_open(struct inode *inode, struct file *file)
43{
44 unsigned long flags;
45 struct snd_card *card;
46 struct snd_ctl_file *ctl;
47 int i, err;
48
49 err = stream_open(inode, file);
50 if (err < 0)
51 return err;
52
53 card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL);
54 if (!card) {
55 err = -ENODEV;
56 goto __error1;
57 }
58 err = snd_card_file_add(card, file);
59 if (err < 0) {
60 err = -ENODEV;
61 goto __error1;
62 }
63 if (!try_module_get(card->module)) {
64 err = -EFAULT;
65 goto __error2;
66 }
67 ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
68 if (ctl == NULL) {
69 err = -ENOMEM;
70 goto __error;
71 }
72 INIT_LIST_HEAD(&ctl->events);
73 init_waitqueue_head(&ctl->change_sleep);
74 spin_lock_init(&ctl->read_lock);
75 ctl->card = card;
76 for (i = 0; i < SND_CTL_SUBDEV_ITEMS; i++)
77 ctl->preferred_subdevice[i] = -1;
78 ctl->pid = get_pid(task_pid(current));
79 file->private_data = ctl;
80 write_lock_irqsave(&card->ctl_files_rwlock, flags);
81 list_add_tail(&ctl->list, &card->ctl_files);
82 write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
83 snd_card_unref(card);
84 return 0;
85
86 __error:
87 module_put(card->module);
88 __error2:
89 snd_card_file_remove(card, file);
90 __error1:
91 if (card)
92 snd_card_unref(card);
93 return err;
94}
95
96static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl)
97{
98 unsigned long flags;
99 struct snd_kctl_event *cread;
100
101 spin_lock_irqsave(&ctl->read_lock, flags);
102 while (!list_empty(&ctl->events)) {
103 cread = snd_kctl_event(ctl->events.next);
104 list_del(&cread->list);
105 kfree(cread);
106 }
107 spin_unlock_irqrestore(&ctl->read_lock, flags);
108}
109
110static int snd_ctl_release(struct inode *inode, struct file *file)
111{
112 unsigned long flags;
113 struct snd_card *card;
114 struct snd_ctl_file *ctl;
115 struct snd_kcontrol *control;
116 unsigned int idx;
117
118 ctl = file->private_data;
119 file->private_data = NULL;
120 card = ctl->card;
121 write_lock_irqsave(&card->ctl_files_rwlock, flags);
122 list_del(&ctl->list);
123 write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
124 down_write(&card->controls_rwsem);
125 list_for_each_entry(control, &card->controls, list)
126 for (idx = 0; idx < control->count; idx++)
127 if (control->vd[idx].owner == ctl)
128 control->vd[idx].owner = NULL;
129 up_write(&card->controls_rwsem);
130 snd_ctl_empty_read_queue(ctl);
131 put_pid(ctl->pid);
132 kfree(ctl);
133 module_put(card->module);
134 snd_card_file_remove(card, file);
135 return 0;
136}
137
138/**
139 * snd_ctl_notify - Send notification to user-space for a control change
140 * @card: the card to send notification
141 * @mask: the event mask, SNDRV_CTL_EVENT_*
142 * @id: the ctl element id to send notification
143 *
144 * This function adds an event record with the given id and mask, appends
145 * to the list and wakes up the user-space for notification. This can be
146 * called in the atomic context.
147 */
148void snd_ctl_notify(struct snd_card *card, unsigned int mask,
149 struct snd_ctl_elem_id *id)
150{
151 unsigned long flags;
152 struct snd_ctl_file *ctl;
153 struct snd_kctl_event *ev;
154
155 if (snd_BUG_ON(!card || !id))
156 return;
157 if (card->shutdown)
158 return;
159 read_lock_irqsave(&card->ctl_files_rwlock, flags);
160#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
161 card->mixer_oss_change_count++;
162#endif
163 list_for_each_entry(ctl, &card->ctl_files, list) {
164 if (!ctl->subscribed)
165 continue;
166 spin_lock(&ctl->read_lock);
167 list_for_each_entry(ev, &ctl->events, list) {
168 if (ev->id.numid == id->numid) {
169 ev->mask |= mask;
170 goto _found;
171 }
172 }
173 ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
174 if (ev) {
175 ev->id = *id;
176 ev->mask = mask;
177 list_add_tail(&ev->list, &ctl->events);
178 } else {
179 dev_err(card->dev, "No memory available to allocate event\n");
180 }
181 _found:
182 wake_up(&ctl->change_sleep);
183 spin_unlock(&ctl->read_lock);
184 kill_fasync(&ctl->fasync, SIGIO, POLL_IN);
185 }
186 read_unlock_irqrestore(&card->ctl_files_rwlock, flags);
187}
188EXPORT_SYMBOL(snd_ctl_notify);
189
190/**
191 * snd_ctl_notify_one - Send notification to user-space for a control change
192 * @card: the card to send notification
193 * @mask: the event mask, SNDRV_CTL_EVENT_*
194 * @kctl: the pointer with the control instance
195 * @ioff: the additional offset to the control index
196 *
197 * This function calls snd_ctl_notify() and does additional jobs
198 * like LED state changes.
199 */
200void snd_ctl_notify_one(struct snd_card *card, unsigned int mask,
201 struct snd_kcontrol *kctl, unsigned int ioff)
202{
203 struct snd_ctl_elem_id id = kctl->id;
204 struct snd_ctl_layer_ops *lops;
205
206 id.index += ioff;
207 id.numid += ioff;
208 snd_ctl_notify(card, mask, &id);
209 down_read(&snd_ctl_layer_rwsem);
210 for (lops = snd_ctl_layer; lops; lops = lops->next)
211 lops->lnotify(card, mask, kctl, ioff);
212 up_read(&snd_ctl_layer_rwsem);
213}
214EXPORT_SYMBOL(snd_ctl_notify_one);
215
216/**
217 * snd_ctl_new - create a new control instance with some elements
218 * @kctl: the pointer to store new control instance
219 * @count: the number of elements in this control
220 * @access: the default access flags for elements in this control
221 * @file: given when locking these elements
222 *
223 * Allocates a memory object for a new control instance. The instance has
224 * elements as many as the given number (@count). Each element has given
225 * access permissions (@access). Each element is locked when @file is given.
226 *
227 * Return: 0 on success, error code on failure
228 */
229static int snd_ctl_new(struct snd_kcontrol **kctl, unsigned int count,
230 unsigned int access, struct snd_ctl_file *file)
231{
232 unsigned int idx;
233
234 if (count == 0 || count > MAX_CONTROL_COUNT)
235 return -EINVAL;
236
237 *kctl = kzalloc(struct_size(*kctl, vd, count), GFP_KERNEL);
238 if (!*kctl)
239 return -ENOMEM;
240
241 for (idx = 0; idx < count; idx++) {
242 (*kctl)->vd[idx].access = access;
243 (*kctl)->vd[idx].owner = file;
244 }
245 (*kctl)->count = count;
246
247 return 0;
248}
249
250/**
251 * snd_ctl_new1 - create a control instance from the template
252 * @ncontrol: the initialization record
253 * @private_data: the private data to set
254 *
255 * Allocates a new struct snd_kcontrol instance and initialize from the given
256 * template. When the access field of ncontrol is 0, it's assumed as
257 * READWRITE access. When the count field is 0, it's assumes as one.
258 *
259 * Return: The pointer of the newly generated instance, or %NULL on failure.
260 */
261struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
262 void *private_data)
263{
264 struct snd_kcontrol *kctl;
265 unsigned int count;
266 unsigned int access;
267 int err;
268
269 if (snd_BUG_ON(!ncontrol || !ncontrol->info))
270 return NULL;
271
272 count = ncontrol->count;
273 if (count == 0)
274 count = 1;
275
276 access = ncontrol->access;
277 if (access == 0)
278 access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
279 access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE |
280 SNDRV_CTL_ELEM_ACCESS_VOLATILE |
281 SNDRV_CTL_ELEM_ACCESS_INACTIVE |
282 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE |
283 SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND |
284 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK |
285 SNDRV_CTL_ELEM_ACCESS_LED_MASK |
286 SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK);
287
288 err = snd_ctl_new(&kctl, count, access, NULL);
289 if (err < 0)
290 return NULL;
291
292 /* The 'numid' member is decided when calling snd_ctl_add(). */
293 kctl->id.iface = ncontrol->iface;
294 kctl->id.device = ncontrol->device;
295 kctl->id.subdevice = ncontrol->subdevice;
296 if (ncontrol->name) {
297 strscpy(kctl->id.name, ncontrol->name, sizeof(kctl->id.name));
298 if (strcmp(ncontrol->name, kctl->id.name) != 0)
299 pr_warn("ALSA: Control name '%s' truncated to '%s'\n",
300 ncontrol->name, kctl->id.name);
301 }
302 kctl->id.index = ncontrol->index;
303
304 kctl->info = ncontrol->info;
305 kctl->get = ncontrol->get;
306 kctl->put = ncontrol->put;
307 kctl->tlv.p = ncontrol->tlv.p;
308
309 kctl->private_value = ncontrol->private_value;
310 kctl->private_data = private_data;
311
312 return kctl;
313}
314EXPORT_SYMBOL(snd_ctl_new1);
315
316/**
317 * snd_ctl_free_one - release the control instance
318 * @kcontrol: the control instance
319 *
320 * Releases the control instance created via snd_ctl_new()
321 * or snd_ctl_new1().
322 * Don't call this after the control was added to the card.
323 */
324void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
325{
326 if (kcontrol) {
327 if (kcontrol->private_free)
328 kcontrol->private_free(kcontrol);
329 kfree(kcontrol);
330 }
331}
332EXPORT_SYMBOL(snd_ctl_free_one);
333
334static bool snd_ctl_remove_numid_conflict(struct snd_card *card,
335 unsigned int count)
336{
337 struct snd_kcontrol *kctl;
338
339 /* Make sure that the ids assigned to the control do not wrap around */
340 if (card->last_numid >= UINT_MAX - count)
341 card->last_numid = 0;
342
343 list_for_each_entry(kctl, &card->controls, list) {
344 if (kctl->id.numid < card->last_numid + 1 + count &&
345 kctl->id.numid + kctl->count > card->last_numid + 1) {
346 card->last_numid = kctl->id.numid + kctl->count - 1;
347 return true;
348 }
349 }
350 return false;
351}
352
353static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
354{
355 unsigned int iter = 100000;
356
357 while (snd_ctl_remove_numid_conflict(card, count)) {
358 if (--iter == 0) {
359 /* this situation is very unlikely */
360 dev_err(card->dev, "unable to allocate new control numid\n");
361 return -ENOMEM;
362 }
363 }
364 return 0;
365}
366
367enum snd_ctl_add_mode {
368 CTL_ADD_EXCLUSIVE, CTL_REPLACE, CTL_ADD_ON_REPLACE,
369};
370
371/* add/replace a new kcontrol object; call with card->controls_rwsem locked */
372static int __snd_ctl_add_replace(struct snd_card *card,
373 struct snd_kcontrol *kcontrol,
374 enum snd_ctl_add_mode mode)
375{
376 struct snd_ctl_elem_id id;
377 unsigned int idx;
378 struct snd_kcontrol *old;
379 int err;
380
381 id = kcontrol->id;
382 if (id.index > UINT_MAX - kcontrol->count)
383 return -EINVAL;
384
385 old = snd_ctl_find_id(card, &id);
386 if (!old) {
387 if (mode == CTL_REPLACE)
388 return -EINVAL;
389 } else {
390 if (mode == CTL_ADD_EXCLUSIVE) {
391 dev_err(card->dev,
392 "control %i:%i:%i:%s:%i is already present\n",
393 id.iface, id.device, id.subdevice, id.name,
394 id.index);
395 return -EBUSY;
396 }
397
398 err = snd_ctl_remove(card, old);
399 if (err < 0)
400 return err;
401 }
402
403 if (snd_ctl_find_hole(card, kcontrol->count) < 0)
404 return -ENOMEM;
405
406 list_add_tail(&kcontrol->list, &card->controls);
407 card->controls_count += kcontrol->count;
408 kcontrol->id.numid = card->last_numid + 1;
409 card->last_numid += kcontrol->count;
410
411 for (idx = 0; idx < kcontrol->count; idx++)
412 snd_ctl_notify_one(card, SNDRV_CTL_EVENT_MASK_ADD, kcontrol, idx);
413
414 return 0;
415}
416
417static int snd_ctl_add_replace(struct snd_card *card,
418 struct snd_kcontrol *kcontrol,
419 enum snd_ctl_add_mode mode)
420{
421 int err = -EINVAL;
422
423 if (! kcontrol)
424 return err;
425 if (snd_BUG_ON(!card || !kcontrol->info))
426 goto error;
427
428 down_write(&card->controls_rwsem);
429 err = __snd_ctl_add_replace(card, kcontrol, mode);
430 up_write(&card->controls_rwsem);
431 if (err < 0)
432 goto error;
433 return 0;
434
435 error:
436 snd_ctl_free_one(kcontrol);
437 return err;
438}
439
440/**
441 * snd_ctl_add - add the control instance to the card
442 * @card: the card instance
443 * @kcontrol: the control instance to add
444 *
445 * Adds the control instance created via snd_ctl_new() or
446 * snd_ctl_new1() to the given card. Assigns also an unique
447 * numid used for fast search.
448 *
449 * It frees automatically the control which cannot be added.
450 *
451 * Return: Zero if successful, or a negative error code on failure.
452 *
453 */
454int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
455{
456 return snd_ctl_add_replace(card, kcontrol, CTL_ADD_EXCLUSIVE);
457}
458EXPORT_SYMBOL(snd_ctl_add);
459
460/**
461 * snd_ctl_replace - replace the control instance of the card
462 * @card: the card instance
463 * @kcontrol: the control instance to replace
464 * @add_on_replace: add the control if not already added
465 *
466 * Replaces the given control. If the given control does not exist
467 * and the add_on_replace flag is set, the control is added. If the
468 * control exists, it is destroyed first.
469 *
470 * It frees automatically the control which cannot be added or replaced.
471 *
472 * Return: Zero if successful, or a negative error code on failure.
473 */
474int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol,
475 bool add_on_replace)
476{
477 return snd_ctl_add_replace(card, kcontrol,
478 add_on_replace ? CTL_ADD_ON_REPLACE : CTL_REPLACE);
479}
480EXPORT_SYMBOL(snd_ctl_replace);
481
482/**
483 * snd_ctl_remove - remove the control from the card and release it
484 * @card: the card instance
485 * @kcontrol: the control instance to remove
486 *
487 * Removes the control from the card and then releases the instance.
488 * You don't need to call snd_ctl_free_one(). You must be in
489 * the write lock - down_write(&card->controls_rwsem).
490 *
491 * Return: 0 if successful, or a negative error code on failure.
492 */
493int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
494{
495 unsigned int idx;
496
497 if (snd_BUG_ON(!card || !kcontrol))
498 return -EINVAL;
499 list_del(&kcontrol->list);
500 card->controls_count -= kcontrol->count;
501 for (idx = 0; idx < kcontrol->count; idx++)
502 snd_ctl_notify_one(card, SNDRV_CTL_EVENT_MASK_REMOVE, kcontrol, idx);
503 snd_ctl_free_one(kcontrol);
504 return 0;
505}
506EXPORT_SYMBOL(snd_ctl_remove);
507
508/**
509 * snd_ctl_remove_id - remove the control of the given id and release it
510 * @card: the card instance
511 * @id: the control id to remove
512 *
513 * Finds the control instance with the given id, removes it from the
514 * card list and releases it.
515 *
516 * Return: 0 if successful, or a negative error code on failure.
517 */
518int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
519{
520 struct snd_kcontrol *kctl;
521 int ret;
522
523 down_write(&card->controls_rwsem);
524 kctl = snd_ctl_find_id(card, id);
525 if (kctl == NULL) {
526 up_write(&card->controls_rwsem);
527 return -ENOENT;
528 }
529 ret = snd_ctl_remove(card, kctl);
530 up_write(&card->controls_rwsem);
531 return ret;
532}
533EXPORT_SYMBOL(snd_ctl_remove_id);
534
535/**
536 * snd_ctl_remove_user_ctl - remove and release the unlocked user control
537 * @file: active control handle
538 * @id: the control id to remove
539 *
540 * Finds the control instance with the given id, removes it from the
541 * card list and releases it.
542 *
543 * Return: 0 if successful, or a negative error code on failure.
544 */
545static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
546 struct snd_ctl_elem_id *id)
547{
548 struct snd_card *card = file->card;
549 struct snd_kcontrol *kctl;
550 int idx, ret;
551
552 down_write(&card->controls_rwsem);
553 kctl = snd_ctl_find_id(card, id);
554 if (kctl == NULL) {
555 ret = -ENOENT;
556 goto error;
557 }
558 if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
559 ret = -EINVAL;
560 goto error;
561 }
562 for (idx = 0; idx < kctl->count; idx++)
563 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
564 ret = -EBUSY;
565 goto error;
566 }
567 ret = snd_ctl_remove(card, kctl);
568error:
569 up_write(&card->controls_rwsem);
570 return ret;
571}
572
573/**
574 * snd_ctl_activate_id - activate/inactivate the control of the given id
575 * @card: the card instance
576 * @id: the control id to activate/inactivate
577 * @active: non-zero to activate
578 *
579 * Finds the control instance with the given id, and activate or
580 * inactivate the control together with notification, if changed.
581 * The given ID data is filled with full information.
582 *
583 * Return: 0 if unchanged, 1 if changed, or a negative error code on failure.
584 */
585int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
586 int active)
587{
588 struct snd_kcontrol *kctl;
589 struct snd_kcontrol_volatile *vd;
590 unsigned int index_offset;
591 int ret;
592
593 down_write(&card->controls_rwsem);
594 kctl = snd_ctl_find_id(card, id);
595 if (kctl == NULL) {
596 ret = -ENOENT;
597 goto unlock;
598 }
599 index_offset = snd_ctl_get_ioff(kctl, id);
600 vd = &kctl->vd[index_offset];
601 ret = 0;
602 if (active) {
603 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE))
604 goto unlock;
605 vd->access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
606 } else {
607 if (vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE)
608 goto unlock;
609 vd->access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE;
610 }
611 snd_ctl_build_ioff(id, kctl, index_offset);
612 downgrade_write(&card->controls_rwsem);
613 snd_ctl_notify_one(card, SNDRV_CTL_EVENT_MASK_INFO, kctl, index_offset);
614 up_read(&card->controls_rwsem);
615 return 1;
616
617 unlock:
618 up_write(&card->controls_rwsem);
619 return ret;
620}
621EXPORT_SYMBOL_GPL(snd_ctl_activate_id);
622
623/**
624 * snd_ctl_rename_id - replace the id of a control on the card
625 * @card: the card instance
626 * @src_id: the old id
627 * @dst_id: the new id
628 *
629 * Finds the control with the old id from the card, and replaces the
630 * id with the new one.
631 *
632 * Return: Zero if successful, or a negative error code on failure.
633 */
634int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
635 struct snd_ctl_elem_id *dst_id)
636{
637 struct snd_kcontrol *kctl;
638
639 down_write(&card->controls_rwsem);
640 kctl = snd_ctl_find_id(card, src_id);
641 if (kctl == NULL) {
642 up_write(&card->controls_rwsem);
643 return -ENOENT;
644 }
645 kctl->id = *dst_id;
646 kctl->id.numid = card->last_numid + 1;
647 card->last_numid += kctl->count;
648 up_write(&card->controls_rwsem);
649 return 0;
650}
651EXPORT_SYMBOL(snd_ctl_rename_id);
652
653/**
654 * snd_ctl_find_numid - find the control instance with the given number-id
655 * @card: the card instance
656 * @numid: the number-id to search
657 *
658 * Finds the control instance with the given number-id from the card.
659 *
660 * The caller must down card->controls_rwsem before calling this function
661 * (if the race condition can happen).
662 *
663 * Return: The pointer of the instance if found, or %NULL if not.
664 *
665 */
666struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid)
667{
668 struct snd_kcontrol *kctl;
669
670 if (snd_BUG_ON(!card || !numid))
671 return NULL;
672 list_for_each_entry(kctl, &card->controls, list) {
673 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
674 return kctl;
675 }
676 return NULL;
677}
678EXPORT_SYMBOL(snd_ctl_find_numid);
679
680/**
681 * snd_ctl_find_id - find the control instance with the given id
682 * @card: the card instance
683 * @id: the id to search
684 *
685 * Finds the control instance with the given id from the card.
686 *
687 * The caller must down card->controls_rwsem before calling this function
688 * (if the race condition can happen).
689 *
690 * Return: The pointer of the instance if found, or %NULL if not.
691 *
692 */
693struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
694 struct snd_ctl_elem_id *id)
695{
696 struct snd_kcontrol *kctl;
697
698 if (snd_BUG_ON(!card || !id))
699 return NULL;
700 if (id->numid != 0)
701 return snd_ctl_find_numid(card, id->numid);
702 list_for_each_entry(kctl, &card->controls, list) {
703 if (kctl->id.iface != id->iface)
704 continue;
705 if (kctl->id.device != id->device)
706 continue;
707 if (kctl->id.subdevice != id->subdevice)
708 continue;
709 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
710 continue;
711 if (kctl->id.index > id->index)
712 continue;
713 if (kctl->id.index + kctl->count <= id->index)
714 continue;
715 return kctl;
716 }
717 return NULL;
718}
719EXPORT_SYMBOL(snd_ctl_find_id);
720
721static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
722 unsigned int cmd, void __user *arg)
723{
724 struct snd_ctl_card_info *info;
725
726 info = kzalloc(sizeof(*info), GFP_KERNEL);
727 if (! info)
728 return -ENOMEM;
729 down_read(&snd_ioctl_rwsem);
730 info->card = card->number;
731 strscpy(info->id, card->id, sizeof(info->id));
732 strscpy(info->driver, card->driver, sizeof(info->driver));
733 strscpy(info->name, card->shortname, sizeof(info->name));
734 strscpy(info->longname, card->longname, sizeof(info->longname));
735 strscpy(info->mixername, card->mixername, sizeof(info->mixername));
736 strscpy(info->components, card->components, sizeof(info->components));
737 up_read(&snd_ioctl_rwsem);
738 if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
739 kfree(info);
740 return -EFAULT;
741 }
742 kfree(info);
743 return 0;
744}
745
746static int snd_ctl_elem_list(struct snd_card *card,
747 struct snd_ctl_elem_list *list)
748{
749 struct snd_kcontrol *kctl;
750 struct snd_ctl_elem_id id;
751 unsigned int offset, space, jidx;
752 int err = 0;
753
754 offset = list->offset;
755 space = list->space;
756
757 down_read(&card->controls_rwsem);
758 list->count = card->controls_count;
759 list->used = 0;
760 if (space > 0) {
761 list_for_each_entry(kctl, &card->controls, list) {
762 if (offset >= kctl->count) {
763 offset -= kctl->count;
764 continue;
765 }
766 for (jidx = offset; jidx < kctl->count; jidx++) {
767 snd_ctl_build_ioff(&id, kctl, jidx);
768 if (copy_to_user(list->pids + list->used, &id,
769 sizeof(id))) {
770 err = -EFAULT;
771 goto out;
772 }
773 list->used++;
774 if (!--space)
775 goto out;
776 }
777 offset = 0;
778 }
779 }
780 out:
781 up_read(&card->controls_rwsem);
782 return err;
783}
784
785static int snd_ctl_elem_list_user(struct snd_card *card,
786 struct snd_ctl_elem_list __user *_list)
787{
788 struct snd_ctl_elem_list list;
789 int err;
790
791 if (copy_from_user(&list, _list, sizeof(list)))
792 return -EFAULT;
793 err = snd_ctl_elem_list(card, &list);
794 if (err)
795 return err;
796 if (copy_to_user(_list, &list, sizeof(list)))
797 return -EFAULT;
798
799 return 0;
800}
801
802/* Check whether the given kctl info is valid */
803static int snd_ctl_check_elem_info(struct snd_card *card,
804 const struct snd_ctl_elem_info *info)
805{
806 static const unsigned int max_value_counts[] = {
807 [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = 128,
808 [SNDRV_CTL_ELEM_TYPE_INTEGER] = 128,
809 [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = 128,
810 [SNDRV_CTL_ELEM_TYPE_BYTES] = 512,
811 [SNDRV_CTL_ELEM_TYPE_IEC958] = 1,
812 [SNDRV_CTL_ELEM_TYPE_INTEGER64] = 64,
813 };
814
815 if (info->type < SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
816 info->type > SNDRV_CTL_ELEM_TYPE_INTEGER64) {
817 if (card)
818 dev_err(card->dev,
819 "control %i:%i:%i:%s:%i: invalid type %d\n",
820 info->id.iface, info->id.device,
821 info->id.subdevice, info->id.name,
822 info->id.index, info->type);
823 return -EINVAL;
824 }
825 if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED &&
826 info->value.enumerated.items == 0) {
827 if (card)
828 dev_err(card->dev,
829 "control %i:%i:%i:%s:%i: zero enum items\n",
830 info->id.iface, info->id.device,
831 info->id.subdevice, info->id.name,
832 info->id.index);
833 return -EINVAL;
834 }
835 if (info->count > max_value_counts[info->type]) {
836 if (card)
837 dev_err(card->dev,
838 "control %i:%i:%i:%s:%i: invalid count %d\n",
839 info->id.iface, info->id.device,
840 info->id.subdevice, info->id.name,
841 info->id.index, info->count);
842 return -EINVAL;
843 }
844
845 return 0;
846}
847
848/* The capacity of struct snd_ctl_elem_value.value.*/
849static const unsigned int value_sizes[] = {
850 [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = sizeof(long),
851 [SNDRV_CTL_ELEM_TYPE_INTEGER] = sizeof(long),
852 [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = sizeof(unsigned int),
853 [SNDRV_CTL_ELEM_TYPE_BYTES] = sizeof(unsigned char),
854 [SNDRV_CTL_ELEM_TYPE_IEC958] = sizeof(struct snd_aes_iec958),
855 [SNDRV_CTL_ELEM_TYPE_INTEGER64] = sizeof(long long),
856};
857
858#ifdef CONFIG_SND_CTL_VALIDATION
859/* fill the remaining snd_ctl_elem_value data with the given pattern */
860static void fill_remaining_elem_value(struct snd_ctl_elem_value *control,
861 struct snd_ctl_elem_info *info,
862 u32 pattern)
863{
864 size_t offset = value_sizes[info->type] * info->count;
865
866 offset = DIV_ROUND_UP(offset, sizeof(u32));
867 memset32((u32 *)control->value.bytes.data + offset, pattern,
868 sizeof(control->value) / sizeof(u32) - offset);
869}
870
871/* check whether the given integer ctl value is valid */
872static int sanity_check_int_value(struct snd_card *card,
873 const struct snd_ctl_elem_value *control,
874 const struct snd_ctl_elem_info *info,
875 int i)
876{
877 long long lval, lmin, lmax, lstep;
878 u64 rem;
879
880 switch (info->type) {
881 default:
882 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
883 lval = control->value.integer.value[i];
884 lmin = 0;
885 lmax = 1;
886 lstep = 0;
887 break;
888 case SNDRV_CTL_ELEM_TYPE_INTEGER:
889 lval = control->value.integer.value[i];
890 lmin = info->value.integer.min;
891 lmax = info->value.integer.max;
892 lstep = info->value.integer.step;
893 break;
894 case SNDRV_CTL_ELEM_TYPE_INTEGER64:
895 lval = control->value.integer64.value[i];
896 lmin = info->value.integer64.min;
897 lmax = info->value.integer64.max;
898 lstep = info->value.integer64.step;
899 break;
900 case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
901 lval = control->value.enumerated.item[i];
902 lmin = 0;
903 lmax = info->value.enumerated.items - 1;
904 lstep = 0;
905 break;
906 }
907
908 if (lval < lmin || lval > lmax) {
909 dev_err(card->dev,
910 "control %i:%i:%i:%s:%i: value out of range %lld (%lld/%lld) at count %i\n",
911 control->id.iface, control->id.device,
912 control->id.subdevice, control->id.name,
913 control->id.index, lval, lmin, lmax, i);
914 return -EINVAL;
915 }
916 if (lstep) {
917 div64_u64_rem(lval, lstep, &rem);
918 if (rem) {
919 dev_err(card->dev,
920 "control %i:%i:%i:%s:%i: unaligned value %lld (step %lld) at count %i\n",
921 control->id.iface, control->id.device,
922 control->id.subdevice, control->id.name,
923 control->id.index, lval, lstep, i);
924 return -EINVAL;
925 }
926 }
927
928 return 0;
929}
930
931/* perform sanity checks to the given snd_ctl_elem_value object */
932static int sanity_check_elem_value(struct snd_card *card,
933 const struct snd_ctl_elem_value *control,
934 const struct snd_ctl_elem_info *info,
935 u32 pattern)
936{
937 size_t offset;
938 int i, ret = 0;
939 u32 *p;
940
941 switch (info->type) {
942 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
943 case SNDRV_CTL_ELEM_TYPE_INTEGER:
944 case SNDRV_CTL_ELEM_TYPE_INTEGER64:
945 case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
946 for (i = 0; i < info->count; i++) {
947 ret = sanity_check_int_value(card, control, info, i);
948 if (ret < 0)
949 return ret;
950 }
951 break;
952 default:
953 break;
954 }
955
956 /* check whether the remaining area kept untouched */
957 offset = value_sizes[info->type] * info->count;
958 offset = DIV_ROUND_UP(offset, sizeof(u32));
959 p = (u32 *)control->value.bytes.data + offset;
960 for (; offset < sizeof(control->value) / sizeof(u32); offset++, p++) {
961 if (*p != pattern) {
962 ret = -EINVAL;
963 break;
964 }
965 *p = 0; /* clear the checked area */
966 }
967
968 return ret;
969}
970#else
971static inline void fill_remaining_elem_value(struct snd_ctl_elem_value *control,
972 struct snd_ctl_elem_info *info,
973 u32 pattern)
974{
975}
976
977static inline int sanity_check_elem_value(struct snd_card *card,
978 struct snd_ctl_elem_value *control,
979 struct snd_ctl_elem_info *info,
980 u32 pattern)
981{
982 return 0;
983}
984#endif
985
986static int __snd_ctl_elem_info(struct snd_card *card,
987 struct snd_kcontrol *kctl,
988 struct snd_ctl_elem_info *info,
989 struct snd_ctl_file *ctl)
990{
991 struct snd_kcontrol_volatile *vd;
992 unsigned int index_offset;
993 int result;
994
995#ifdef CONFIG_SND_DEBUG
996 info->access = 0;
997#endif
998 result = snd_power_ref_and_wait(card);
999 if (!result)
1000 result = kctl->info(kctl, info);
1001 snd_power_unref(card);
1002 if (result >= 0) {
1003 snd_BUG_ON(info->access);
1004 index_offset = snd_ctl_get_ioff(kctl, &info->id);
1005 vd = &kctl->vd[index_offset];
1006 snd_ctl_build_ioff(&info->id, kctl, index_offset);
1007 info->access = vd->access;
1008 if (vd->owner) {
1009 info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
1010 if (vd->owner == ctl)
1011 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
1012 info->owner = pid_vnr(vd->owner->pid);
1013 } else {
1014 info->owner = -1;
1015 }
1016 if (!snd_ctl_skip_validation(info) &&
1017 snd_ctl_check_elem_info(card, info) < 0)
1018 result = -EINVAL;
1019 }
1020 return result;
1021}
1022
1023static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
1024 struct snd_ctl_elem_info *info)
1025{
1026 struct snd_card *card = ctl->card;
1027 struct snd_kcontrol *kctl;
1028 int result;
1029
1030 down_read(&card->controls_rwsem);
1031 kctl = snd_ctl_find_id(card, &info->id);
1032 if (kctl == NULL)
1033 result = -ENOENT;
1034 else
1035 result = __snd_ctl_elem_info(card, kctl, info, ctl);
1036 up_read(&card->controls_rwsem);
1037 return result;
1038}
1039
1040static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
1041 struct snd_ctl_elem_info __user *_info)
1042{
1043 struct snd_ctl_elem_info info;
1044 int result;
1045
1046 if (copy_from_user(&info, _info, sizeof(info)))
1047 return -EFAULT;
1048 result = snd_ctl_elem_info(ctl, &info);
1049 if (result < 0)
1050 return result;
1051 /* drop internal access flags */
1052 info.access &= ~(SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK|
1053 SNDRV_CTL_ELEM_ACCESS_LED_MASK);
1054 if (copy_to_user(_info, &info, sizeof(info)))
1055 return -EFAULT;
1056 return result;
1057}
1058
1059static int snd_ctl_elem_read(struct snd_card *card,
1060 struct snd_ctl_elem_value *control)
1061{
1062 struct snd_kcontrol *kctl;
1063 struct snd_kcontrol_volatile *vd;
1064 unsigned int index_offset;
1065 struct snd_ctl_elem_info info;
1066 const u32 pattern = 0xdeadbeef;
1067 int ret;
1068
1069 kctl = snd_ctl_find_id(card, &control->id);
1070 if (kctl == NULL)
1071 return -ENOENT;
1072
1073 index_offset = snd_ctl_get_ioff(kctl, &control->id);
1074 vd = &kctl->vd[index_offset];
1075 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_READ) || kctl->get == NULL)
1076 return -EPERM;
1077
1078 snd_ctl_build_ioff(&control->id, kctl, index_offset);
1079
1080#ifdef CONFIG_SND_CTL_VALIDATION
1081 /* info is needed only for validation */
1082 memset(&info, 0, sizeof(info));
1083 info.id = control->id;
1084 ret = __snd_ctl_elem_info(card, kctl, &info, NULL);
1085 if (ret < 0)
1086 return ret;
1087#endif
1088
1089 if (!snd_ctl_skip_validation(&info))
1090 fill_remaining_elem_value(control, &info, pattern);
1091 ret = snd_power_ref_and_wait(card);
1092 if (!ret)
1093 ret = kctl->get(kctl, control);
1094 snd_power_unref(card);
1095 if (ret < 0)
1096 return ret;
1097 if (!snd_ctl_skip_validation(&info) &&
1098 sanity_check_elem_value(card, control, &info, pattern) < 0) {
1099 dev_err(card->dev,
1100 "control %i:%i:%i:%s:%i: access overflow\n",
1101 control->id.iface, control->id.device,
1102 control->id.subdevice, control->id.name,
1103 control->id.index);
1104 return -EINVAL;
1105 }
1106 return ret;
1107}
1108
1109static int snd_ctl_elem_read_user(struct snd_card *card,
1110 struct snd_ctl_elem_value __user *_control)
1111{
1112 struct snd_ctl_elem_value *control;
1113 int result;
1114
1115 control = memdup_user(_control, sizeof(*control));
1116 if (IS_ERR(control))
1117 return PTR_ERR(control);
1118
1119 down_read(&card->controls_rwsem);
1120 result = snd_ctl_elem_read(card, control);
1121 up_read(&card->controls_rwsem);
1122 if (result < 0)
1123 goto error;
1124
1125 if (copy_to_user(_control, control, sizeof(*control)))
1126 result = -EFAULT;
1127 error:
1128 kfree(control);
1129 return result;
1130}
1131
1132static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
1133 struct snd_ctl_elem_value *control)
1134{
1135 struct snd_kcontrol *kctl;
1136 struct snd_kcontrol_volatile *vd;
1137 unsigned int index_offset;
1138 int result;
1139
1140 down_write(&card->controls_rwsem);
1141 kctl = snd_ctl_find_id(card, &control->id);
1142 if (kctl == NULL) {
1143 up_write(&card->controls_rwsem);
1144 return -ENOENT;
1145 }
1146
1147 index_offset = snd_ctl_get_ioff(kctl, &control->id);
1148 vd = &kctl->vd[index_offset];
1149 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) || kctl->put == NULL ||
1150 (file && vd->owner && vd->owner != file)) {
1151 up_write(&card->controls_rwsem);
1152 return -EPERM;
1153 }
1154
1155 snd_ctl_build_ioff(&control->id, kctl, index_offset);
1156 result = snd_power_ref_and_wait(card);
1157 if (!result)
1158 result = kctl->put(kctl, control);
1159 snd_power_unref(card);
1160 if (result < 0) {
1161 up_write(&card->controls_rwsem);
1162 return result;
1163 }
1164
1165 if (result > 0) {
1166 downgrade_write(&card->controls_rwsem);
1167 snd_ctl_notify_one(card, SNDRV_CTL_EVENT_MASK_VALUE, kctl, index_offset);
1168 up_read(&card->controls_rwsem);
1169 } else {
1170 up_write(&card->controls_rwsem);
1171 }
1172
1173 return 0;
1174}
1175
1176static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
1177 struct snd_ctl_elem_value __user *_control)
1178{
1179 struct snd_ctl_elem_value *control;
1180 struct snd_card *card;
1181 int result;
1182
1183 control = memdup_user(_control, sizeof(*control));
1184 if (IS_ERR(control))
1185 return PTR_ERR(control);
1186
1187 card = file->card;
1188 result = snd_ctl_elem_write(card, file, control);
1189 if (result < 0)
1190 goto error;
1191
1192 if (copy_to_user(_control, control, sizeof(*control)))
1193 result = -EFAULT;
1194 error:
1195 kfree(control);
1196 return result;
1197}
1198
1199static int snd_ctl_elem_lock(struct snd_ctl_file *file,
1200 struct snd_ctl_elem_id __user *_id)
1201{
1202 struct snd_card *card = file->card;
1203 struct snd_ctl_elem_id id;
1204 struct snd_kcontrol *kctl;
1205 struct snd_kcontrol_volatile *vd;
1206 int result;
1207
1208 if (copy_from_user(&id, _id, sizeof(id)))
1209 return -EFAULT;
1210 down_write(&card->controls_rwsem);
1211 kctl = snd_ctl_find_id(card, &id);
1212 if (kctl == NULL) {
1213 result = -ENOENT;
1214 } else {
1215 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
1216 if (vd->owner != NULL)
1217 result = -EBUSY;
1218 else {
1219 vd->owner = file;
1220 result = 0;
1221 }
1222 }
1223 up_write(&card->controls_rwsem);
1224 return result;
1225}
1226
1227static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
1228 struct snd_ctl_elem_id __user *_id)
1229{
1230 struct snd_card *card = file->card;
1231 struct snd_ctl_elem_id id;
1232 struct snd_kcontrol *kctl;
1233 struct snd_kcontrol_volatile *vd;
1234 int result;
1235
1236 if (copy_from_user(&id, _id, sizeof(id)))
1237 return -EFAULT;
1238 down_write(&card->controls_rwsem);
1239 kctl = snd_ctl_find_id(card, &id);
1240 if (kctl == NULL) {
1241 result = -ENOENT;
1242 } else {
1243 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
1244 if (vd->owner == NULL)
1245 result = -EINVAL;
1246 else if (vd->owner != file)
1247 result = -EPERM;
1248 else {
1249 vd->owner = NULL;
1250 result = 0;
1251 }
1252 }
1253 up_write(&card->controls_rwsem);
1254 return result;
1255}
1256
1257struct user_element {
1258 struct snd_ctl_elem_info info;
1259 struct snd_card *card;
1260 char *elem_data; /* element data */
1261 unsigned long elem_data_size; /* size of element data in bytes */
1262 void *tlv_data; /* TLV data */
1263 unsigned long tlv_data_size; /* TLV data size */
1264 void *priv_data; /* private data (like strings for enumerated type) */
1265};
1266
1267// check whether the addition (in bytes) of user ctl element may overflow the limit.
1268static bool check_user_elem_overflow(struct snd_card *card, ssize_t add)
1269{
1270 return (ssize_t)card->user_ctl_alloc_size + add > max_user_ctl_alloc_size;
1271}
1272
1273static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
1274 struct snd_ctl_elem_info *uinfo)
1275{
1276 struct user_element *ue = kcontrol->private_data;
1277 unsigned int offset;
1278
1279 offset = snd_ctl_get_ioff(kcontrol, &uinfo->id);
1280 *uinfo = ue->info;
1281 snd_ctl_build_ioff(&uinfo->id, kcontrol, offset);
1282
1283 return 0;
1284}
1285
1286static int snd_ctl_elem_user_enum_info(struct snd_kcontrol *kcontrol,
1287 struct snd_ctl_elem_info *uinfo)
1288{
1289 struct user_element *ue = kcontrol->private_data;
1290 const char *names;
1291 unsigned int item;
1292 unsigned int offset;
1293
1294 item = uinfo->value.enumerated.item;
1295
1296 offset = snd_ctl_get_ioff(kcontrol, &uinfo->id);
1297 *uinfo = ue->info;
1298 snd_ctl_build_ioff(&uinfo->id, kcontrol, offset);
1299
1300 item = min(item, uinfo->value.enumerated.items - 1);
1301 uinfo->value.enumerated.item = item;
1302
1303 names = ue->priv_data;
1304 for (; item > 0; --item)
1305 names += strlen(names) + 1;
1306 strcpy(uinfo->value.enumerated.name, names);
1307
1308 return 0;
1309}
1310
1311static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
1312 struct snd_ctl_elem_value *ucontrol)
1313{
1314 struct user_element *ue = kcontrol->private_data;
1315 unsigned int size = ue->elem_data_size;
1316 char *src = ue->elem_data +
1317 snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size;
1318
1319 memcpy(&ucontrol->value, src, size);
1320 return 0;
1321}
1322
1323static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
1324 struct snd_ctl_elem_value *ucontrol)
1325{
1326 int change;
1327 struct user_element *ue = kcontrol->private_data;
1328 unsigned int size = ue->elem_data_size;
1329 char *dst = ue->elem_data +
1330 snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size;
1331
1332 change = memcmp(&ucontrol->value, dst, size) != 0;
1333 if (change)
1334 memcpy(dst, &ucontrol->value, size);
1335 return change;
1336}
1337
1338/* called in controls_rwsem write lock */
1339static int replace_user_tlv(struct snd_kcontrol *kctl, unsigned int __user *buf,
1340 unsigned int size)
1341{
1342 struct user_element *ue = kctl->private_data;
1343 unsigned int *container;
1344 unsigned int mask = 0;
1345 int i;
1346 int change;
1347
1348 if (size > 1024 * 128) /* sane value */
1349 return -EINVAL;
1350
1351 // does the TLV size change cause overflow?
1352 if (check_user_elem_overflow(ue->card, (ssize_t)(size - ue->tlv_data_size)))
1353 return -ENOMEM;
1354
1355 container = vmemdup_user(buf, size);
1356 if (IS_ERR(container))
1357 return PTR_ERR(container);
1358
1359 change = ue->tlv_data_size != size;
1360 if (!change)
1361 change = memcmp(ue->tlv_data, container, size) != 0;
1362 if (!change) {
1363 kvfree(container);
1364 return 0;
1365 }
1366
1367 if (ue->tlv_data == NULL) {
1368 /* Now TLV data is available. */
1369 for (i = 0; i < kctl->count; ++i)
1370 kctl->vd[i].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
1371 mask = SNDRV_CTL_EVENT_MASK_INFO;
1372 } else {
1373 ue->card->user_ctl_alloc_size -= ue->tlv_data_size;
1374 ue->tlv_data_size = 0;
1375 kvfree(ue->tlv_data);
1376 }
1377
1378 ue->tlv_data = container;
1379 ue->tlv_data_size = size;
1380 // decremented at private_free.
1381 ue->card->user_ctl_alloc_size += size;
1382
1383 mask |= SNDRV_CTL_EVENT_MASK_TLV;
1384 for (i = 0; i < kctl->count; ++i)
1385 snd_ctl_notify_one(ue->card, mask, kctl, i);
1386
1387 return change;
1388}
1389
1390static int read_user_tlv(struct snd_kcontrol *kctl, unsigned int __user *buf,
1391 unsigned int size)
1392{
1393 struct user_element *ue = kctl->private_data;
1394
1395 if (ue->tlv_data_size == 0 || ue->tlv_data == NULL)
1396 return -ENXIO;
1397
1398 if (size < ue->tlv_data_size)
1399 return -ENOSPC;
1400
1401 if (copy_to_user(buf, ue->tlv_data, ue->tlv_data_size))
1402 return -EFAULT;
1403
1404 return 0;
1405}
1406
1407static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kctl, int op_flag,
1408 unsigned int size, unsigned int __user *buf)
1409{
1410 if (op_flag == SNDRV_CTL_TLV_OP_WRITE)
1411 return replace_user_tlv(kctl, buf, size);
1412 else
1413 return read_user_tlv(kctl, buf, size);
1414}
1415
1416/* called in controls_rwsem write lock */
1417static int snd_ctl_elem_init_enum_names(struct user_element *ue)
1418{
1419 char *names, *p;
1420 size_t buf_len, name_len;
1421 unsigned int i;
1422 const uintptr_t user_ptrval = ue->info.value.enumerated.names_ptr;
1423
1424 buf_len = ue->info.value.enumerated.names_length;
1425 if (buf_len > 64 * 1024)
1426 return -EINVAL;
1427
1428 if (check_user_elem_overflow(ue->card, buf_len))
1429 return -ENOMEM;
1430 names = vmemdup_user((const void __user *)user_ptrval, buf_len);
1431 if (IS_ERR(names))
1432 return PTR_ERR(names);
1433
1434 /* check that there are enough valid names */
1435 p = names;
1436 for (i = 0; i < ue->info.value.enumerated.items; ++i) {
1437 name_len = strnlen(p, buf_len);
1438 if (name_len == 0 || name_len >= 64 || name_len == buf_len) {
1439 kvfree(names);
1440 return -EINVAL;
1441 }
1442 p += name_len + 1;
1443 buf_len -= name_len + 1;
1444 }
1445
1446 ue->priv_data = names;
1447 ue->info.value.enumerated.names_ptr = 0;
1448 // increment the allocation size; decremented again at private_free.
1449 ue->card->user_ctl_alloc_size += ue->info.value.enumerated.names_length;
1450
1451 return 0;
1452}
1453
1454static size_t compute_user_elem_size(size_t size, unsigned int count)
1455{
1456 return sizeof(struct user_element) + size * count;
1457}
1458
1459static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
1460{
1461 struct user_element *ue = kcontrol->private_data;
1462
1463 // decrement the allocation size.
1464 ue->card->user_ctl_alloc_size -= compute_user_elem_size(ue->elem_data_size, kcontrol->count);
1465 ue->card->user_ctl_alloc_size -= ue->tlv_data_size;
1466 if (ue->priv_data)
1467 ue->card->user_ctl_alloc_size -= ue->info.value.enumerated.names_length;
1468
1469 kvfree(ue->tlv_data);
1470 kvfree(ue->priv_data);
1471 kfree(ue);
1472}
1473
1474static int snd_ctl_elem_add(struct snd_ctl_file *file,
1475 struct snd_ctl_elem_info *info, int replace)
1476{
1477 struct snd_card *card = file->card;
1478 struct snd_kcontrol *kctl;
1479 unsigned int count;
1480 unsigned int access;
1481 long private_size;
1482 size_t alloc_size;
1483 struct user_element *ue;
1484 unsigned int offset;
1485 int err;
1486
1487 if (!*info->id.name)
1488 return -EINVAL;
1489 if (strnlen(info->id.name, sizeof(info->id.name)) >= sizeof(info->id.name))
1490 return -EINVAL;
1491
1492 /* Delete a control to replace them if needed. */
1493 if (replace) {
1494 info->id.numid = 0;
1495 err = snd_ctl_remove_user_ctl(file, &info->id);
1496 if (err)
1497 return err;
1498 }
1499
1500 /* Check the number of elements for this userspace control. */
1501 count = info->owner;
1502 if (count == 0)
1503 count = 1;
1504
1505 /* Arrange access permissions if needed. */
1506 access = info->access;
1507 if (access == 0)
1508 access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
1509 access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE |
1510 SNDRV_CTL_ELEM_ACCESS_INACTIVE |
1511 SNDRV_CTL_ELEM_ACCESS_TLV_WRITE);
1512
1513 /* In initial state, nothing is available as TLV container. */
1514 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE)
1515 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1516 access |= SNDRV_CTL_ELEM_ACCESS_USER;
1517
1518 /*
1519 * Check information and calculate the size of data specific to
1520 * this userspace control.
1521 */
1522 /* pass NULL to card for suppressing error messages */
1523 err = snd_ctl_check_elem_info(NULL, info);
1524 if (err < 0)
1525 return err;
1526 /* user-space control doesn't allow zero-size data */
1527 if (info->count < 1)
1528 return -EINVAL;
1529 private_size = value_sizes[info->type] * info->count;
1530 alloc_size = compute_user_elem_size(private_size, count);
1531
1532 down_write(&card->controls_rwsem);
1533 if (check_user_elem_overflow(card, alloc_size)) {
1534 err = -ENOMEM;
1535 goto unlock;
1536 }
1537
1538 /*
1539 * Keep memory object for this userspace control. After passing this
1540 * code block, the instance should be freed by snd_ctl_free_one().
1541 *
1542 * Note that these elements in this control are locked.
1543 */
1544 err = snd_ctl_new(&kctl, count, access, file);
1545 if (err < 0)
1546 goto unlock;
1547 memcpy(&kctl->id, &info->id, sizeof(kctl->id));
1548 ue = kzalloc(alloc_size, GFP_KERNEL);
1549 if (!ue) {
1550 kfree(kctl);
1551 err = -ENOMEM;
1552 goto unlock;
1553 }
1554 kctl->private_data = ue;
1555 kctl->private_free = snd_ctl_elem_user_free;
1556
1557 // increment the allocated size; decremented again at private_free.
1558 card->user_ctl_alloc_size += alloc_size;
1559
1560 /* Set private data for this userspace control. */
1561 ue->card = card;
1562 ue->info = *info;
1563 ue->info.access = 0;
1564 ue->elem_data = (char *)ue + sizeof(*ue);
1565 ue->elem_data_size = private_size;
1566 if (ue->info.type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) {
1567 err = snd_ctl_elem_init_enum_names(ue);
1568 if (err < 0) {
1569 snd_ctl_free_one(kctl);
1570 goto unlock;
1571 }
1572 }
1573
1574 /* Set callback functions. */
1575 if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED)
1576 kctl->info = snd_ctl_elem_user_enum_info;
1577 else
1578 kctl->info = snd_ctl_elem_user_info;
1579 if (access & SNDRV_CTL_ELEM_ACCESS_READ)
1580 kctl->get = snd_ctl_elem_user_get;
1581 if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
1582 kctl->put = snd_ctl_elem_user_put;
1583 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE)
1584 kctl->tlv.c = snd_ctl_elem_user_tlv;
1585
1586 /* This function manage to free the instance on failure. */
1587 err = __snd_ctl_add_replace(card, kctl, CTL_ADD_EXCLUSIVE);
1588 if (err < 0) {
1589 snd_ctl_free_one(kctl);
1590 goto unlock;
1591 }
1592 offset = snd_ctl_get_ioff(kctl, &info->id);
1593 snd_ctl_build_ioff(&info->id, kctl, offset);
1594 /*
1595 * Here we cannot fill any field for the number of elements added by
1596 * this operation because there're no specific fields. The usage of
1597 * 'owner' field for this purpose may cause any bugs to userspace
1598 * applications because the field originally means PID of a process
1599 * which locks the element.
1600 */
1601 unlock:
1602 up_write(&card->controls_rwsem);
1603 return err;
1604}
1605
1606static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1607 struct snd_ctl_elem_info __user *_info, int replace)
1608{
1609 struct snd_ctl_elem_info info;
1610 int err;
1611
1612 if (copy_from_user(&info, _info, sizeof(info)))
1613 return -EFAULT;
1614 err = snd_ctl_elem_add(file, &info, replace);
1615 if (err < 0)
1616 return err;
1617 if (copy_to_user(_info, &info, sizeof(info))) {
1618 snd_ctl_remove_user_ctl(file, &info.id);
1619 return -EFAULT;
1620 }
1621
1622 return 0;
1623}
1624
1625static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1626 struct snd_ctl_elem_id __user *_id)
1627{
1628 struct snd_ctl_elem_id id;
1629
1630 if (copy_from_user(&id, _id, sizeof(id)))
1631 return -EFAULT;
1632 return snd_ctl_remove_user_ctl(file, &id);
1633}
1634
1635static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
1636{
1637 int subscribe;
1638 if (get_user(subscribe, ptr))
1639 return -EFAULT;
1640 if (subscribe < 0) {
1641 subscribe = file->subscribed;
1642 if (put_user(subscribe, ptr))
1643 return -EFAULT;
1644 return 0;
1645 }
1646 if (subscribe) {
1647 file->subscribed = 1;
1648 return 0;
1649 } else if (file->subscribed) {
1650 snd_ctl_empty_read_queue(file);
1651 file->subscribed = 0;
1652 }
1653 return 0;
1654}
1655
1656static int call_tlv_handler(struct snd_ctl_file *file, int op_flag,
1657 struct snd_kcontrol *kctl,
1658 struct snd_ctl_elem_id *id,
1659 unsigned int __user *buf, unsigned int size)
1660{
1661 static const struct {
1662 int op;
1663 int perm;
1664 } pairs[] = {
1665 {SNDRV_CTL_TLV_OP_READ, SNDRV_CTL_ELEM_ACCESS_TLV_READ},
1666 {SNDRV_CTL_TLV_OP_WRITE, SNDRV_CTL_ELEM_ACCESS_TLV_WRITE},
1667 {SNDRV_CTL_TLV_OP_CMD, SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND},
1668 };
1669 struct snd_kcontrol_volatile *vd = &kctl->vd[snd_ctl_get_ioff(kctl, id)];
1670 int i, ret;
1671
1672 /* Check support of the request for this element. */
1673 for (i = 0; i < ARRAY_SIZE(pairs); ++i) {
1674 if (op_flag == pairs[i].op && (vd->access & pairs[i].perm))
1675 break;
1676 }
1677 if (i == ARRAY_SIZE(pairs))
1678 return -ENXIO;
1679
1680 if (kctl->tlv.c == NULL)
1681 return -ENXIO;
1682
1683 /* Write and command operations are not allowed for locked element. */
1684 if (op_flag != SNDRV_CTL_TLV_OP_READ &&
1685 vd->owner != NULL && vd->owner != file)
1686 return -EPERM;
1687
1688 ret = snd_power_ref_and_wait(file->card);
1689 if (!ret)
1690 ret = kctl->tlv.c(kctl, op_flag, size, buf);
1691 snd_power_unref(file->card);
1692 return ret;
1693}
1694
1695static int read_tlv_buf(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id,
1696 unsigned int __user *buf, unsigned int size)
1697{
1698 struct snd_kcontrol_volatile *vd = &kctl->vd[snd_ctl_get_ioff(kctl, id)];
1699 unsigned int len;
1700
1701 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ))
1702 return -ENXIO;
1703
1704 if (kctl->tlv.p == NULL)
1705 return -ENXIO;
1706
1707 len = sizeof(unsigned int) * 2 + kctl->tlv.p[1];
1708 if (size < len)
1709 return -ENOMEM;
1710
1711 if (copy_to_user(buf, kctl->tlv.p, len))
1712 return -EFAULT;
1713
1714 return 0;
1715}
1716
1717static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1718 struct snd_ctl_tlv __user *buf,
1719 int op_flag)
1720{
1721 struct snd_ctl_tlv header;
1722 unsigned int __user *container;
1723 unsigned int container_size;
1724 struct snd_kcontrol *kctl;
1725 struct snd_ctl_elem_id id;
1726 struct snd_kcontrol_volatile *vd;
1727
1728 if (copy_from_user(&header, buf, sizeof(header)))
1729 return -EFAULT;
1730
1731 /* In design of control core, numerical ID starts at 1. */
1732 if (header.numid == 0)
1733 return -EINVAL;
1734
1735 /* At least, container should include type and length fields. */
1736 if (header.length < sizeof(unsigned int) * 2)
1737 return -EINVAL;
1738 container_size = header.length;
1739 container = buf->tlv;
1740
1741 kctl = snd_ctl_find_numid(file->card, header.numid);
1742 if (kctl == NULL)
1743 return -ENOENT;
1744
1745 /* Calculate index of the element in this set. */
1746 id = kctl->id;
1747 snd_ctl_build_ioff(&id, kctl, header.numid - id.numid);
1748 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
1749
1750 if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
1751 return call_tlv_handler(file, op_flag, kctl, &id, container,
1752 container_size);
1753 } else {
1754 if (op_flag == SNDRV_CTL_TLV_OP_READ) {
1755 return read_tlv_buf(kctl, &id, container,
1756 container_size);
1757 }
1758 }
1759
1760 /* Not supported. */
1761 return -ENXIO;
1762}
1763
1764static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1765{
1766 struct snd_ctl_file *ctl;
1767 struct snd_card *card;
1768 struct snd_kctl_ioctl *p;
1769 void __user *argp = (void __user *)arg;
1770 int __user *ip = argp;
1771 int err;
1772
1773 ctl = file->private_data;
1774 card = ctl->card;
1775 if (snd_BUG_ON(!card))
1776 return -ENXIO;
1777 switch (cmd) {
1778 case SNDRV_CTL_IOCTL_PVERSION:
1779 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1780 case SNDRV_CTL_IOCTL_CARD_INFO:
1781 return snd_ctl_card_info(card, ctl, cmd, argp);
1782 case SNDRV_CTL_IOCTL_ELEM_LIST:
1783 return snd_ctl_elem_list_user(card, argp);
1784 case SNDRV_CTL_IOCTL_ELEM_INFO:
1785 return snd_ctl_elem_info_user(ctl, argp);
1786 case SNDRV_CTL_IOCTL_ELEM_READ:
1787 return snd_ctl_elem_read_user(card, argp);
1788 case SNDRV_CTL_IOCTL_ELEM_WRITE:
1789 return snd_ctl_elem_write_user(ctl, argp);
1790 case SNDRV_CTL_IOCTL_ELEM_LOCK:
1791 return snd_ctl_elem_lock(ctl, argp);
1792 case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1793 return snd_ctl_elem_unlock(ctl, argp);
1794 case SNDRV_CTL_IOCTL_ELEM_ADD:
1795 return snd_ctl_elem_add_user(ctl, argp, 0);
1796 case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1797 return snd_ctl_elem_add_user(ctl, argp, 1);
1798 case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1799 return snd_ctl_elem_remove(ctl, argp);
1800 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1801 return snd_ctl_subscribe_events(ctl, ip);
1802 case SNDRV_CTL_IOCTL_TLV_READ:
1803 down_read(&ctl->card->controls_rwsem);
1804 err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_READ);
1805 up_read(&ctl->card->controls_rwsem);
1806 return err;
1807 case SNDRV_CTL_IOCTL_TLV_WRITE:
1808 down_write(&ctl->card->controls_rwsem);
1809 err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_WRITE);
1810 up_write(&ctl->card->controls_rwsem);
1811 return err;
1812 case SNDRV_CTL_IOCTL_TLV_COMMAND:
1813 down_write(&ctl->card->controls_rwsem);
1814 err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_CMD);
1815 up_write(&ctl->card->controls_rwsem);
1816 return err;
1817 case SNDRV_CTL_IOCTL_POWER:
1818 return -ENOPROTOOPT;
1819 case SNDRV_CTL_IOCTL_POWER_STATE:
1820 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1821 }
1822 down_read(&snd_ioctl_rwsem);
1823 list_for_each_entry(p, &snd_control_ioctls, list) {
1824 err = p->fioctl(card, ctl, cmd, arg);
1825 if (err != -ENOIOCTLCMD) {
1826 up_read(&snd_ioctl_rwsem);
1827 return err;
1828 }
1829 }
1830 up_read(&snd_ioctl_rwsem);
1831 dev_dbg(card->dev, "unknown ioctl = 0x%x\n", cmd);
1832 return -ENOTTY;
1833}
1834
1835static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1836 size_t count, loff_t * offset)
1837{
1838 struct snd_ctl_file *ctl;
1839 int err = 0;
1840 ssize_t result = 0;
1841
1842 ctl = file->private_data;
1843 if (snd_BUG_ON(!ctl || !ctl->card))
1844 return -ENXIO;
1845 if (!ctl->subscribed)
1846 return -EBADFD;
1847 if (count < sizeof(struct snd_ctl_event))
1848 return -EINVAL;
1849 spin_lock_irq(&ctl->read_lock);
1850 while (count >= sizeof(struct snd_ctl_event)) {
1851 struct snd_ctl_event ev;
1852 struct snd_kctl_event *kev;
1853 while (list_empty(&ctl->events)) {
1854 wait_queue_entry_t wait;
1855 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1856 err = -EAGAIN;
1857 goto __end_lock;
1858 }
1859 init_waitqueue_entry(&wait, current);
1860 add_wait_queue(&ctl->change_sleep, &wait);
1861 set_current_state(TASK_INTERRUPTIBLE);
1862 spin_unlock_irq(&ctl->read_lock);
1863 schedule();
1864 remove_wait_queue(&ctl->change_sleep, &wait);
1865 if (ctl->card->shutdown)
1866 return -ENODEV;
1867 if (signal_pending(current))
1868 return -ERESTARTSYS;
1869 spin_lock_irq(&ctl->read_lock);
1870 }
1871 kev = snd_kctl_event(ctl->events.next);
1872 ev.type = SNDRV_CTL_EVENT_ELEM;
1873 ev.data.elem.mask = kev->mask;
1874 ev.data.elem.id = kev->id;
1875 list_del(&kev->list);
1876 spin_unlock_irq(&ctl->read_lock);
1877 kfree(kev);
1878 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
1879 err = -EFAULT;
1880 goto __end;
1881 }
1882 spin_lock_irq(&ctl->read_lock);
1883 buffer += sizeof(struct snd_ctl_event);
1884 count -= sizeof(struct snd_ctl_event);
1885 result += sizeof(struct snd_ctl_event);
1886 }
1887 __end_lock:
1888 spin_unlock_irq(&ctl->read_lock);
1889 __end:
1890 return result > 0 ? result : err;
1891}
1892
1893static __poll_t snd_ctl_poll(struct file *file, poll_table * wait)
1894{
1895 __poll_t mask;
1896 struct snd_ctl_file *ctl;
1897
1898 ctl = file->private_data;
1899 if (!ctl->subscribed)
1900 return 0;
1901 poll_wait(file, &ctl->change_sleep, wait);
1902
1903 mask = 0;
1904 if (!list_empty(&ctl->events))
1905 mask |= EPOLLIN | EPOLLRDNORM;
1906
1907 return mask;
1908}
1909
1910/*
1911 * register the device-specific control-ioctls.
1912 * called from each device manager like pcm.c, hwdep.c, etc.
1913 */
1914static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1915{
1916 struct snd_kctl_ioctl *pn;
1917
1918 pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
1919 if (pn == NULL)
1920 return -ENOMEM;
1921 pn->fioctl = fcn;
1922 down_write(&snd_ioctl_rwsem);
1923 list_add_tail(&pn->list, lists);
1924 up_write(&snd_ioctl_rwsem);
1925 return 0;
1926}
1927
1928/**
1929 * snd_ctl_register_ioctl - register the device-specific control-ioctls
1930 * @fcn: ioctl callback function
1931 *
1932 * called from each device manager like pcm.c, hwdep.c, etc.
1933 */
1934int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1935{
1936 return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1937}
1938EXPORT_SYMBOL(snd_ctl_register_ioctl);
1939
1940#ifdef CONFIG_COMPAT
1941/**
1942 * snd_ctl_register_ioctl_compat - register the device-specific 32bit compat
1943 * control-ioctls
1944 * @fcn: ioctl callback function
1945 */
1946int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1947{
1948 return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1949}
1950EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
1951#endif
1952
1953/*
1954 * de-register the device-specific control-ioctls.
1955 */
1956static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1957 struct list_head *lists)
1958{
1959 struct snd_kctl_ioctl *p;
1960
1961 if (snd_BUG_ON(!fcn))
1962 return -EINVAL;
1963 down_write(&snd_ioctl_rwsem);
1964 list_for_each_entry(p, lists, list) {
1965 if (p->fioctl == fcn) {
1966 list_del(&p->list);
1967 up_write(&snd_ioctl_rwsem);
1968 kfree(p);
1969 return 0;
1970 }
1971 }
1972 up_write(&snd_ioctl_rwsem);
1973 snd_BUG();
1974 return -EINVAL;
1975}
1976
1977/**
1978 * snd_ctl_unregister_ioctl - de-register the device-specific control-ioctls
1979 * @fcn: ioctl callback function to unregister
1980 */
1981int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1982{
1983 return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1984}
1985EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1986
1987#ifdef CONFIG_COMPAT
1988/**
1989 * snd_ctl_unregister_ioctl_compat - de-register the device-specific compat
1990 * 32bit control-ioctls
1991 * @fcn: ioctl callback function to unregister
1992 */
1993int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1994{
1995 return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1996}
1997EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
1998#endif
1999
2000static int snd_ctl_fasync(int fd, struct file * file, int on)
2001{
2002 struct snd_ctl_file *ctl;
2003
2004 ctl = file->private_data;
2005 return fasync_helper(fd, file, on, &ctl->fasync);
2006}
2007
2008/* return the preferred subdevice number if already assigned;
2009 * otherwise return -1
2010 */
2011int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type)
2012{
2013 struct snd_ctl_file *kctl;
2014 int subdevice = -1;
2015 unsigned long flags;
2016
2017 read_lock_irqsave(&card->ctl_files_rwlock, flags);
2018 list_for_each_entry(kctl, &card->ctl_files, list) {
2019 if (kctl->pid == task_pid(current)) {
2020 subdevice = kctl->preferred_subdevice[type];
2021 if (subdevice != -1)
2022 break;
2023 }
2024 }
2025 read_unlock_irqrestore(&card->ctl_files_rwlock, flags);
2026 return subdevice;
2027}
2028EXPORT_SYMBOL_GPL(snd_ctl_get_preferred_subdevice);
2029
2030/*
2031 * ioctl32 compat
2032 */
2033#ifdef CONFIG_COMPAT
2034#include "control_compat.c"
2035#else
2036#define snd_ctl_ioctl_compat NULL
2037#endif
2038
2039/*
2040 * control layers (audio LED etc.)
2041 */
2042
2043/**
2044 * snd_ctl_request_layer - request to use the layer
2045 * @module_name: Name of the kernel module (NULL == build-in)
2046 *
2047 * Return an error code when the module cannot be loaded.
2048 */
2049int snd_ctl_request_layer(const char *module_name)
2050{
2051 struct snd_ctl_layer_ops *lops;
2052
2053 if (module_name == NULL)
2054 return 0;
2055 down_read(&snd_ctl_layer_rwsem);
2056 for (lops = snd_ctl_layer; lops; lops = lops->next)
2057 if (strcmp(lops->module_name, module_name) == 0)
2058 break;
2059 up_read(&snd_ctl_layer_rwsem);
2060 if (lops)
2061 return 0;
2062 return request_module(module_name);
2063}
2064EXPORT_SYMBOL_GPL(snd_ctl_request_layer);
2065
2066/**
2067 * snd_ctl_register_layer - register new control layer
2068 * @lops: operation structure
2069 *
2070 * The new layer can track all control elements and do additional
2071 * operations on top (like audio LED handling).
2072 */
2073void snd_ctl_register_layer(struct snd_ctl_layer_ops *lops)
2074{
2075 struct snd_card *card;
2076 int card_number;
2077
2078 down_write(&snd_ctl_layer_rwsem);
2079 lops->next = snd_ctl_layer;
2080 snd_ctl_layer = lops;
2081 up_write(&snd_ctl_layer_rwsem);
2082 for (card_number = 0; card_number < SNDRV_CARDS; card_number++) {
2083 card = snd_card_ref(card_number);
2084 if (card) {
2085 down_read(&card->controls_rwsem);
2086 lops->lregister(card);
2087 up_read(&card->controls_rwsem);
2088 snd_card_unref(card);
2089 }
2090 }
2091}
2092EXPORT_SYMBOL_GPL(snd_ctl_register_layer);
2093
2094/**
2095 * snd_ctl_disconnect_layer - disconnect control layer
2096 * @lops: operation structure
2097 *
2098 * It is expected that the information about tracked cards
2099 * is freed before this call (the disconnect callback is
2100 * not called here).
2101 */
2102void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops)
2103{
2104 struct snd_ctl_layer_ops *lops2, *prev_lops2;
2105
2106 down_write(&snd_ctl_layer_rwsem);
2107 for (lops2 = snd_ctl_layer, prev_lops2 = NULL; lops2; lops2 = lops2->next) {
2108 if (lops2 == lops) {
2109 if (!prev_lops2)
2110 snd_ctl_layer = lops->next;
2111 else
2112 prev_lops2->next = lops->next;
2113 break;
2114 }
2115 prev_lops2 = lops2;
2116 }
2117 up_write(&snd_ctl_layer_rwsem);
2118}
2119EXPORT_SYMBOL_GPL(snd_ctl_disconnect_layer);
2120
2121/*
2122 * INIT PART
2123 */
2124
2125static const struct file_operations snd_ctl_f_ops =
2126{
2127 .owner = THIS_MODULE,
2128 .read = snd_ctl_read,
2129 .open = snd_ctl_open,
2130 .release = snd_ctl_release,
2131 .llseek = no_llseek,
2132 .poll = snd_ctl_poll,
2133 .unlocked_ioctl = snd_ctl_ioctl,
2134 .compat_ioctl = snd_ctl_ioctl_compat,
2135 .fasync = snd_ctl_fasync,
2136};
2137
2138/*
2139 * registration of the control device
2140 */
2141static int snd_ctl_dev_register(struct snd_device *device)
2142{
2143 struct snd_card *card = device->device_data;
2144 struct snd_ctl_layer_ops *lops;
2145 int err;
2146
2147 err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
2148 &snd_ctl_f_ops, card, &card->ctl_dev);
2149 if (err < 0)
2150 return err;
2151 down_read(&card->controls_rwsem);
2152 down_read(&snd_ctl_layer_rwsem);
2153 for (lops = snd_ctl_layer; lops; lops = lops->next)
2154 lops->lregister(card);
2155 up_read(&snd_ctl_layer_rwsem);
2156 up_read(&card->controls_rwsem);
2157 return 0;
2158}
2159
2160/*
2161 * disconnection of the control device
2162 */
2163static int snd_ctl_dev_disconnect(struct snd_device *device)
2164{
2165 struct snd_card *card = device->device_data;
2166 struct snd_ctl_file *ctl;
2167 struct snd_ctl_layer_ops *lops;
2168 unsigned long flags;
2169
2170 read_lock_irqsave(&card->ctl_files_rwlock, flags);
2171 list_for_each_entry(ctl, &card->ctl_files, list) {
2172 wake_up(&ctl->change_sleep);
2173 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
2174 }
2175 read_unlock_irqrestore(&card->ctl_files_rwlock, flags);
2176
2177 down_read(&card->controls_rwsem);
2178 down_read(&snd_ctl_layer_rwsem);
2179 for (lops = snd_ctl_layer; lops; lops = lops->next)
2180 lops->ldisconnect(card);
2181 up_read(&snd_ctl_layer_rwsem);
2182 up_read(&card->controls_rwsem);
2183
2184 return snd_unregister_device(&card->ctl_dev);
2185}
2186
2187/*
2188 * free all controls
2189 */
2190static int snd_ctl_dev_free(struct snd_device *device)
2191{
2192 struct snd_card *card = device->device_data;
2193 struct snd_kcontrol *control;
2194
2195 down_write(&card->controls_rwsem);
2196 while (!list_empty(&card->controls)) {
2197 control = snd_kcontrol(card->controls.next);
2198 snd_ctl_remove(card, control);
2199 }
2200 up_write(&card->controls_rwsem);
2201 put_device(&card->ctl_dev);
2202 return 0;
2203}
2204
2205/*
2206 * create control core:
2207 * called from init.c
2208 */
2209int snd_ctl_create(struct snd_card *card)
2210{
2211 static const struct snd_device_ops ops = {
2212 .dev_free = snd_ctl_dev_free,
2213 .dev_register = snd_ctl_dev_register,
2214 .dev_disconnect = snd_ctl_dev_disconnect,
2215 };
2216 int err;
2217
2218 if (snd_BUG_ON(!card))
2219 return -ENXIO;
2220 if (snd_BUG_ON(card->number < 0 || card->number >= SNDRV_CARDS))
2221 return -ENXIO;
2222
2223 snd_device_initialize(&card->ctl_dev, card);
2224 dev_set_name(&card->ctl_dev, "controlC%d", card->number);
2225
2226 err = snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
2227 if (err < 0)
2228 put_device(&card->ctl_dev);
2229 return err;
2230}
2231
2232/*
2233 * Frequently used control callbacks/helpers
2234 */
2235
2236/**
2237 * snd_ctl_boolean_mono_info - Helper function for a standard boolean info
2238 * callback with a mono channel
2239 * @kcontrol: the kcontrol instance
2240 * @uinfo: info to store
2241 *
2242 * This is a function that can be used as info callback for a standard
2243 * boolean control with a single mono channel.
2244 */
2245int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
2246 struct snd_ctl_elem_info *uinfo)
2247{
2248 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
2249 uinfo->count = 1;
2250 uinfo->value.integer.min = 0;
2251 uinfo->value.integer.max = 1;
2252 return 0;
2253}
2254EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
2255
2256/**
2257 * snd_ctl_boolean_stereo_info - Helper function for a standard boolean info
2258 * callback with stereo two channels
2259 * @kcontrol: the kcontrol instance
2260 * @uinfo: info to store
2261 *
2262 * This is a function that can be used as info callback for a standard
2263 * boolean control with stereo two channels.
2264 */
2265int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
2266 struct snd_ctl_elem_info *uinfo)
2267{
2268 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
2269 uinfo->count = 2;
2270 uinfo->value.integer.min = 0;
2271 uinfo->value.integer.max = 1;
2272 return 0;
2273}
2274EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);
2275
2276/**
2277 * snd_ctl_enum_info - fills the info structure for an enumerated control
2278 * @info: the structure to be filled
2279 * @channels: the number of the control's channels; often one
2280 * @items: the number of control values; also the size of @names
2281 * @names: an array containing the names of all control values
2282 *
2283 * Sets all required fields in @info to their appropriate values.
2284 * If the control's accessibility is not the default (readable and writable),
2285 * the caller has to fill @info->access.
2286 *
2287 * Return: Zero.
2288 */
2289int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
2290 unsigned int items, const char *const names[])
2291{
2292 info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
2293 info->count = channels;
2294 info->value.enumerated.items = items;
2295 if (!items)
2296 return 0;
2297 if (info->value.enumerated.item >= items)
2298 info->value.enumerated.item = items - 1;
2299 WARN(strlen(names[info->value.enumerated.item]) >= sizeof(info->value.enumerated.name),
2300 "ALSA: too long item name '%s'\n",
2301 names[info->value.enumerated.item]);
2302 strscpy(info->value.enumerated.name,
2303 names[info->value.enumerated.item],
2304 sizeof(info->value.enumerated.name));
2305 return 0;
2306}
2307EXPORT_SYMBOL(snd_ctl_enum_info);