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