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