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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 i, 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 for (i = 0; i < SND_CTL_SUBDEV_ITEMS; i++)
83 ctl->preferred_subdevice[i] = -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
144/**
145 * snd_ctl_notify - Send notification to user-space for a control change
146 * @card: the card to send notification
147 * @mask: the event mask, SNDRV_CTL_EVENT_*
148 * @id: the ctl element id to send notification
149 *
150 * This function adds an event record with the given id and mask, appends
151 * to the list and wakes up the user-space for notification. This can be
152 * called in the atomic context.
153 */
154void snd_ctl_notify(struct snd_card *card, unsigned int mask,
155 struct snd_ctl_elem_id *id)
156{
157 unsigned long flags;
158 struct snd_ctl_file *ctl;
159 struct snd_kctl_event *ev;
160
161 if (snd_BUG_ON(!card || !id))
162 return;
163 read_lock(&card->ctl_files_rwlock);
164#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
165 card->mixer_oss_change_count++;
166#endif
167 list_for_each_entry(ctl, &card->ctl_files, list) {
168 if (!ctl->subscribed)
169 continue;
170 spin_lock_irqsave(&ctl->read_lock, flags);
171 list_for_each_entry(ev, &ctl->events, list) {
172 if (ev->id.numid == id->numid) {
173 ev->mask |= mask;
174 goto _found;
175 }
176 }
177 ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
178 if (ev) {
179 ev->id = *id;
180 ev->mask = mask;
181 list_add_tail(&ev->list, &ctl->events);
182 } else {
183 dev_err(card->dev, "No memory available to allocate event\n");
184 }
185 _found:
186 wake_up(&ctl->change_sleep);
187 spin_unlock_irqrestore(&ctl->read_lock, flags);
188 kill_fasync(&ctl->fasync, SIGIO, POLL_IN);
189 }
190 read_unlock(&card->ctl_files_rwlock);
191}
192EXPORT_SYMBOL(snd_ctl_notify);
193
194/**
195 * snd_ctl_new - create a new control instance with some elements
196 * @kctl: the pointer to store new control instance
197 * @count: the number of elements in this control
198 * @access: the default access flags for elements in this control
199 * @file: given when locking these elements
200 *
201 * Allocates a memory object for a new control instance. The instance has
202 * elements as many as the given number (@count). Each element has given
203 * access permissions (@access). Each element is locked when @file is given.
204 *
205 * Return: 0 on success, error code on failure
206 */
207static int snd_ctl_new(struct snd_kcontrol **kctl, unsigned int count,
208 unsigned int access, struct snd_ctl_file *file)
209{
210 unsigned int size;
211 unsigned int idx;
212
213 if (count == 0 || count > MAX_CONTROL_COUNT)
214 return -EINVAL;
215
216 size = sizeof(struct snd_kcontrol);
217 size += sizeof(struct snd_kcontrol_volatile) * count;
218
219 *kctl = kzalloc(size, GFP_KERNEL);
220 if (!*kctl)
221 return -ENOMEM;
222
223 for (idx = 0; idx < count; idx++) {
224 (*kctl)->vd[idx].access = access;
225 (*kctl)->vd[idx].owner = file;
226 }
227 (*kctl)->count = count;
228
229 return 0;
230}
231
232/**
233 * snd_ctl_new1 - create a control instance from the template
234 * @ncontrol: the initialization record
235 * @private_data: the private data to set
236 *
237 * Allocates a new struct snd_kcontrol instance and initialize from the given
238 * template. When the access field of ncontrol is 0, it's assumed as
239 * READWRITE access. When the count field is 0, it's assumes as one.
240 *
241 * Return: The pointer of the newly generated instance, or %NULL on failure.
242 */
243struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
244 void *private_data)
245{
246 struct snd_kcontrol *kctl;
247 unsigned int count;
248 unsigned int access;
249 int err;
250
251 if (snd_BUG_ON(!ncontrol || !ncontrol->info))
252 return NULL;
253
254 count = ncontrol->count;
255 if (count == 0)
256 count = 1;
257
258 access = ncontrol->access;
259 if (access == 0)
260 access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
261 access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE |
262 SNDRV_CTL_ELEM_ACCESS_VOLATILE |
263 SNDRV_CTL_ELEM_ACCESS_INACTIVE |
264 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE |
265 SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND |
266 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK);
267
268 err = snd_ctl_new(&kctl, count, access, NULL);
269 if (err < 0)
270 return NULL;
271
272 /* The 'numid' member is decided when calling snd_ctl_add(). */
273 kctl->id.iface = ncontrol->iface;
274 kctl->id.device = ncontrol->device;
275 kctl->id.subdevice = ncontrol->subdevice;
276 if (ncontrol->name) {
277 strlcpy(kctl->id.name, ncontrol->name, sizeof(kctl->id.name));
278 if (strcmp(ncontrol->name, kctl->id.name) != 0)
279 pr_warn("ALSA: Control name '%s' truncated to '%s'\n",
280 ncontrol->name, kctl->id.name);
281 }
282 kctl->id.index = ncontrol->index;
283
284 kctl->info = ncontrol->info;
285 kctl->get = ncontrol->get;
286 kctl->put = ncontrol->put;
287 kctl->tlv.p = ncontrol->tlv.p;
288
289 kctl->private_value = ncontrol->private_value;
290 kctl->private_data = private_data;
291
292 return kctl;
293}
294EXPORT_SYMBOL(snd_ctl_new1);
295
296/**
297 * snd_ctl_free_one - release the control instance
298 * @kcontrol: the control instance
299 *
300 * Releases the control instance created via snd_ctl_new()
301 * or snd_ctl_new1().
302 * Don't call this after the control was added to the card.
303 */
304void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
305{
306 if (kcontrol) {
307 if (kcontrol->private_free)
308 kcontrol->private_free(kcontrol);
309 kfree(kcontrol);
310 }
311}
312EXPORT_SYMBOL(snd_ctl_free_one);
313
314static bool snd_ctl_remove_numid_conflict(struct snd_card *card,
315 unsigned int count)
316{
317 struct snd_kcontrol *kctl;
318
319 /* Make sure that the ids assigned to the control do not wrap around */
320 if (card->last_numid >= UINT_MAX - count)
321 card->last_numid = 0;
322
323 list_for_each_entry(kctl, &card->controls, list) {
324 if (kctl->id.numid < card->last_numid + 1 + count &&
325 kctl->id.numid + kctl->count > card->last_numid + 1) {
326 card->last_numid = kctl->id.numid + kctl->count - 1;
327 return true;
328 }
329 }
330 return false;
331}
332
333static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
334{
335 unsigned int iter = 100000;
336
337 while (snd_ctl_remove_numid_conflict(card, count)) {
338 if (--iter == 0) {
339 /* this situation is very unlikely */
340 dev_err(card->dev, "unable to allocate new control numid\n");
341 return -ENOMEM;
342 }
343 }
344 return 0;
345}
346
347/**
348 * snd_ctl_add - add the control instance to the card
349 * @card: the card instance
350 * @kcontrol: the control instance to add
351 *
352 * Adds the control instance created via snd_ctl_new() or
353 * snd_ctl_new1() to the given card. Assigns also an unique
354 * numid used for fast search.
355 *
356 * It frees automatically the control which cannot be added.
357 *
358 * Return: Zero if successful, or a negative error code on failure.
359 *
360 */
361int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
362{
363 struct snd_ctl_elem_id id;
364 unsigned int idx;
365 unsigned int count;
366 int err = -EINVAL;
367
368 if (! kcontrol)
369 return err;
370 if (snd_BUG_ON(!card || !kcontrol->info))
371 goto error;
372 id = kcontrol->id;
373 if (id.index > UINT_MAX - kcontrol->count)
374 goto error;
375
376 down_write(&card->controls_rwsem);
377 if (snd_ctl_find_id(card, &id)) {
378 up_write(&card->controls_rwsem);
379 dev_err(card->dev, "control %i:%i:%i:%s:%i is already present\n",
380 id.iface,
381 id.device,
382 id.subdevice,
383 id.name,
384 id.index);
385 err = -EBUSY;
386 goto error;
387 }
388 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
389 up_write(&card->controls_rwsem);
390 err = -ENOMEM;
391 goto error;
392 }
393 list_add_tail(&kcontrol->list, &card->controls);
394 card->controls_count += kcontrol->count;
395 kcontrol->id.numid = card->last_numid + 1;
396 card->last_numid += kcontrol->count;
397 id = kcontrol->id;
398 count = kcontrol->count;
399 up_write(&card->controls_rwsem);
400 for (idx = 0; idx < count; idx++, id.index++, id.numid++)
401 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
402 return 0;
403
404 error:
405 snd_ctl_free_one(kcontrol);
406 return err;
407}
408EXPORT_SYMBOL(snd_ctl_add);
409
410/**
411 * snd_ctl_replace - replace the control instance of the card
412 * @card: the card instance
413 * @kcontrol: the control instance to replace
414 * @add_on_replace: add the control if not already added
415 *
416 * Replaces the given control. If the given control does not exist
417 * and the add_on_replace flag is set, the control is added. If the
418 * control exists, it is destroyed first.
419 *
420 * It frees automatically the control which cannot be added or replaced.
421 *
422 * Return: Zero if successful, or a negative error code on failure.
423 */
424int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol,
425 bool add_on_replace)
426{
427 struct snd_ctl_elem_id id;
428 unsigned int count;
429 unsigned int idx;
430 struct snd_kcontrol *old;
431 int ret;
432
433 if (!kcontrol)
434 return -EINVAL;
435 if (snd_BUG_ON(!card || !kcontrol->info)) {
436 ret = -EINVAL;
437 goto error;
438 }
439 id = kcontrol->id;
440 down_write(&card->controls_rwsem);
441 old = snd_ctl_find_id(card, &id);
442 if (!old) {
443 if (add_on_replace)
444 goto add;
445 up_write(&card->controls_rwsem);
446 ret = -EINVAL;
447 goto error;
448 }
449 ret = snd_ctl_remove(card, old);
450 if (ret < 0) {
451 up_write(&card->controls_rwsem);
452 goto error;
453 }
454add:
455 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
456 up_write(&card->controls_rwsem);
457 ret = -ENOMEM;
458 goto error;
459 }
460 list_add_tail(&kcontrol->list, &card->controls);
461 card->controls_count += kcontrol->count;
462 kcontrol->id.numid = card->last_numid + 1;
463 card->last_numid += kcontrol->count;
464 id = kcontrol->id;
465 count = kcontrol->count;
466 up_write(&card->controls_rwsem);
467 for (idx = 0; idx < count; idx++, id.index++, id.numid++)
468 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
469 return 0;
470
471error:
472 snd_ctl_free_one(kcontrol);
473 return ret;
474}
475EXPORT_SYMBOL(snd_ctl_replace);
476
477/**
478 * snd_ctl_remove - remove the control from the card and release it
479 * @card: the card instance
480 * @kcontrol: the control instance to remove
481 *
482 * Removes the control from the card and then releases the instance.
483 * You don't need to call snd_ctl_free_one(). You must be in
484 * the write lock - down_write(&card->controls_rwsem).
485 *
486 * Return: 0 if successful, or a negative error code on failure.
487 */
488int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
489{
490 struct snd_ctl_elem_id id;
491 unsigned int idx;
492
493 if (snd_BUG_ON(!card || !kcontrol))
494 return -EINVAL;
495 list_del(&kcontrol->list);
496 card->controls_count -= kcontrol->count;
497 id = kcontrol->id;
498 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
499 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
500 snd_ctl_free_one(kcontrol);
501 return 0;
502}
503EXPORT_SYMBOL(snd_ctl_remove);
504
505/**
506 * snd_ctl_remove_id - remove the control of the given id and release it
507 * @card: the card instance
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 */
515int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
516{
517 struct snd_kcontrol *kctl;
518 int ret;
519
520 down_write(&card->controls_rwsem);
521 kctl = snd_ctl_find_id(card, id);
522 if (kctl == NULL) {
523 up_write(&card->controls_rwsem);
524 return -ENOENT;
525 }
526 ret = snd_ctl_remove(card, kctl);
527 up_write(&card->controls_rwsem);
528 return ret;
529}
530EXPORT_SYMBOL(snd_ctl_remove_id);
531
532/**
533 * snd_ctl_remove_user_ctl - remove and release the unlocked user control
534 * @file: active control handle
535 * @id: the control id to remove
536 *
537 * Finds the control instance with the given id, removes it from the
538 * card list and releases it.
539 *
540 * Return: 0 if successful, or a negative error code on failure.
541 */
542static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
543 struct snd_ctl_elem_id *id)
544{
545 struct snd_card *card = file->card;
546 struct snd_kcontrol *kctl;
547 int idx, ret;
548
549 down_write(&card->controls_rwsem);
550 kctl = snd_ctl_find_id(card, id);
551 if (kctl == NULL) {
552 ret = -ENOENT;
553 goto error;
554 }
555 if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
556 ret = -EINVAL;
557 goto error;
558 }
559 for (idx = 0; idx < kctl->count; idx++)
560 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
561 ret = -EBUSY;
562 goto error;
563 }
564 ret = snd_ctl_remove(card, kctl);
565 if (ret < 0)
566 goto error;
567 card->user_ctl_count--;
568error:
569 up_write(&card->controls_rwsem);
570 return ret;
571}
572
573/**
574 * snd_ctl_activate_id - activate/inactivate the control of the given id
575 * @card: the card instance
576 * @id: the control id to activate/inactivate
577 * @active: non-zero to activate
578 *
579 * Finds the control instance with the given id, and activate or
580 * inactivate the control together with notification, if changed.
581 * The given ID data is filled with full information.
582 *
583 * Return: 0 if unchanged, 1 if changed, or a negative error code on failure.
584 */
585int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
586 int active)
587{
588 struct snd_kcontrol *kctl;
589 struct snd_kcontrol_volatile *vd;
590 unsigned int index_offset;
591 int ret;
592
593 down_write(&card->controls_rwsem);
594 kctl = snd_ctl_find_id(card, id);
595 if (kctl == NULL) {
596 ret = -ENOENT;
597 goto unlock;
598 }
599 index_offset = snd_ctl_get_ioff(kctl, id);
600 vd = &kctl->vd[index_offset];
601 ret = 0;
602 if (active) {
603 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE))
604 goto unlock;
605 vd->access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
606 } else {
607 if (vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE)
608 goto unlock;
609 vd->access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE;
610 }
611 snd_ctl_build_ioff(id, kctl, index_offset);
612 ret = 1;
613 unlock:
614 up_write(&card->controls_rwsem);
615 if (ret > 0)
616 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, id);
617 return ret;
618}
619EXPORT_SYMBOL_GPL(snd_ctl_activate_id);
620
621/**
622 * snd_ctl_rename_id - replace the id of a control on the card
623 * @card: the card instance
624 * @src_id: the old id
625 * @dst_id: the new id
626 *
627 * Finds the control with the old id from the card, and replaces the
628 * id with the new one.
629 *
630 * Return: Zero if successful, or a negative error code on failure.
631 */
632int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
633 struct snd_ctl_elem_id *dst_id)
634{
635 struct snd_kcontrol *kctl;
636
637 down_write(&card->controls_rwsem);
638 kctl = snd_ctl_find_id(card, src_id);
639 if (kctl == NULL) {
640 up_write(&card->controls_rwsem);
641 return -ENOENT;
642 }
643 kctl->id = *dst_id;
644 kctl->id.numid = card->last_numid + 1;
645 card->last_numid += kctl->count;
646 up_write(&card->controls_rwsem);
647 return 0;
648}
649EXPORT_SYMBOL(snd_ctl_rename_id);
650
651/**
652 * snd_ctl_find_numid - find the control instance with the given number-id
653 * @card: the card instance
654 * @numid: the number-id to search
655 *
656 * Finds the control instance with the given number-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_numid(struct snd_card *card, unsigned int numid)
665{
666 struct snd_kcontrol *kctl;
667
668 if (snd_BUG_ON(!card || !numid))
669 return NULL;
670 list_for_each_entry(kctl, &card->controls, list) {
671 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
672 return kctl;
673 }
674 return NULL;
675}
676EXPORT_SYMBOL(snd_ctl_find_numid);
677
678/**
679 * snd_ctl_find_id - find the control instance with the given id
680 * @card: the card instance
681 * @id: the id to search
682 *
683 * Finds the control instance with the given id from the card.
684 *
685 * The caller must down card->controls_rwsem before calling this function
686 * (if the race condition can happen).
687 *
688 * Return: The pointer of the instance if found, or %NULL if not.
689 *
690 */
691struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
692 struct snd_ctl_elem_id *id)
693{
694 struct snd_kcontrol *kctl;
695
696 if (snd_BUG_ON(!card || !id))
697 return NULL;
698 if (id->numid != 0)
699 return snd_ctl_find_numid(card, id->numid);
700 list_for_each_entry(kctl, &card->controls, list) {
701 if (kctl->id.iface != id->iface)
702 continue;
703 if (kctl->id.device != id->device)
704 continue;
705 if (kctl->id.subdevice != id->subdevice)
706 continue;
707 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
708 continue;
709 if (kctl->id.index > id->index)
710 continue;
711 if (kctl->id.index + kctl->count <= id->index)
712 continue;
713 return kctl;
714 }
715 return NULL;
716}
717EXPORT_SYMBOL(snd_ctl_find_id);
718
719static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
720 unsigned int cmd, void __user *arg)
721{
722 struct snd_ctl_card_info *info;
723
724 info = kzalloc(sizeof(*info), GFP_KERNEL);
725 if (! info)
726 return -ENOMEM;
727 down_read(&snd_ioctl_rwsem);
728 info->card = card->number;
729 strlcpy(info->id, card->id, sizeof(info->id));
730 strlcpy(info->driver, card->driver, sizeof(info->driver));
731 strlcpy(info->name, card->shortname, sizeof(info->name));
732 strlcpy(info->longname, card->longname, sizeof(info->longname));
733 strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
734 strlcpy(info->components, card->components, sizeof(info->components));
735 up_read(&snd_ioctl_rwsem);
736 if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
737 kfree(info);
738 return -EFAULT;
739 }
740 kfree(info);
741 return 0;
742}
743
744static int snd_ctl_elem_list(struct snd_card *card,
745 struct snd_ctl_elem_list __user *_list)
746{
747 struct list_head *plist;
748 struct snd_ctl_elem_list list;
749 struct snd_kcontrol *kctl;
750 struct snd_ctl_elem_id *dst, *id;
751 unsigned int offset, space, jidx;
752
753 if (copy_from_user(&list, _list, sizeof(list)))
754 return -EFAULT;
755 offset = list.offset;
756 space = list.space;
757 /* try limit maximum space */
758 if (space > 16384)
759 return -ENOMEM;
760 if (space > 0) {
761 /* allocate temporary buffer for atomic operation */
762 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
763 if (dst == NULL)
764 return -ENOMEM;
765 down_read(&card->controls_rwsem);
766 list.count = card->controls_count;
767 plist = card->controls.next;
768 while (plist != &card->controls) {
769 if (offset == 0)
770 break;
771 kctl = snd_kcontrol(plist);
772 if (offset < kctl->count)
773 break;
774 offset -= kctl->count;
775 plist = plist->next;
776 }
777 list.used = 0;
778 id = dst;
779 while (space > 0 && plist != &card->controls) {
780 kctl = snd_kcontrol(plist);
781 for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
782 snd_ctl_build_ioff(id, kctl, jidx);
783 id++;
784 space--;
785 list.used++;
786 }
787 plist = plist->next;
788 offset = 0;
789 }
790 up_read(&card->controls_rwsem);
791 if (list.used > 0 &&
792 copy_to_user(list.pids, dst,
793 list.used * sizeof(struct snd_ctl_elem_id))) {
794 vfree(dst);
795 return -EFAULT;
796 }
797 vfree(dst);
798 } else {
799 down_read(&card->controls_rwsem);
800 list.count = card->controls_count;
801 up_read(&card->controls_rwsem);
802 }
803 if (copy_to_user(_list, &list, sizeof(list)))
804 return -EFAULT;
805 return 0;
806}
807
808static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
809 struct snd_ctl_elem_info *info)
810{
811 struct snd_card *card = ctl->card;
812 struct snd_kcontrol *kctl;
813 struct snd_kcontrol_volatile *vd;
814 unsigned int index_offset;
815 int result;
816
817 down_read(&card->controls_rwsem);
818 kctl = snd_ctl_find_id(card, &info->id);
819 if (kctl == NULL) {
820 up_read(&card->controls_rwsem);
821 return -ENOENT;
822 }
823#ifdef CONFIG_SND_DEBUG
824 info->access = 0;
825#endif
826 result = kctl->info(kctl, info);
827 if (result >= 0) {
828 snd_BUG_ON(info->access);
829 index_offset = snd_ctl_get_ioff(kctl, &info->id);
830 vd = &kctl->vd[index_offset];
831 snd_ctl_build_ioff(&info->id, kctl, index_offset);
832 info->access = vd->access;
833 if (vd->owner) {
834 info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
835 if (vd->owner == ctl)
836 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
837 info->owner = pid_vnr(vd->owner->pid);
838 } else {
839 info->owner = -1;
840 }
841 }
842 up_read(&card->controls_rwsem);
843 return result;
844}
845
846static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
847 struct snd_ctl_elem_info __user *_info)
848{
849 struct snd_ctl_elem_info info;
850 int result;
851
852 if (copy_from_user(&info, _info, sizeof(info)))
853 return -EFAULT;
854 snd_power_lock(ctl->card);
855 result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
856 if (result >= 0)
857 result = snd_ctl_elem_info(ctl, &info);
858 snd_power_unlock(ctl->card);
859 if (result >= 0)
860 if (copy_to_user(_info, &info, sizeof(info)))
861 return -EFAULT;
862 return result;
863}
864
865static int snd_ctl_elem_read(struct snd_card *card,
866 struct snd_ctl_elem_value *control)
867{
868 struct snd_kcontrol *kctl;
869 struct snd_kcontrol_volatile *vd;
870 unsigned int index_offset;
871 int result;
872
873 down_read(&card->controls_rwsem);
874 kctl = snd_ctl_find_id(card, &control->id);
875 if (kctl == NULL) {
876 result = -ENOENT;
877 } else {
878 index_offset = snd_ctl_get_ioff(kctl, &control->id);
879 vd = &kctl->vd[index_offset];
880 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
881 kctl->get != NULL) {
882 snd_ctl_build_ioff(&control->id, kctl, index_offset);
883 result = kctl->get(kctl, control);
884 } else
885 result = -EPERM;
886 }
887 up_read(&card->controls_rwsem);
888 return result;
889}
890
891static int snd_ctl_elem_read_user(struct snd_card *card,
892 struct snd_ctl_elem_value __user *_control)
893{
894 struct snd_ctl_elem_value *control;
895 int result;
896
897 control = memdup_user(_control, sizeof(*control));
898 if (IS_ERR(control))
899 return PTR_ERR(control);
900
901 snd_power_lock(card);
902 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
903 if (result >= 0)
904 result = snd_ctl_elem_read(card, control);
905 snd_power_unlock(card);
906 if (result >= 0)
907 if (copy_to_user(_control, control, sizeof(*control)))
908 result = -EFAULT;
909 kfree(control);
910 return result;
911}
912
913static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
914 struct snd_ctl_elem_value *control)
915{
916 struct snd_kcontrol *kctl;
917 struct snd_kcontrol_volatile *vd;
918 unsigned int index_offset;
919 int result;
920
921 down_read(&card->controls_rwsem);
922 kctl = snd_ctl_find_id(card, &control->id);
923 if (kctl == NULL) {
924 result = -ENOENT;
925 } else {
926 index_offset = snd_ctl_get_ioff(kctl, &control->id);
927 vd = &kctl->vd[index_offset];
928 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
929 kctl->put == NULL ||
930 (file && vd->owner && vd->owner != file)) {
931 result = -EPERM;
932 } else {
933 snd_ctl_build_ioff(&control->id, kctl, index_offset);
934 result = kctl->put(kctl, control);
935 }
936 if (result > 0) {
937 struct snd_ctl_elem_id id = control->id;
938 up_read(&card->controls_rwsem);
939 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, &id);
940 return 0;
941 }
942 }
943 up_read(&card->controls_rwsem);
944 return result;
945}
946
947static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
948 struct snd_ctl_elem_value __user *_control)
949{
950 struct snd_ctl_elem_value *control;
951 struct snd_card *card;
952 int result;
953
954 control = memdup_user(_control, sizeof(*control));
955 if (IS_ERR(control))
956 return PTR_ERR(control);
957
958 card = file->card;
959 snd_power_lock(card);
960 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
961 if (result >= 0)
962 result = snd_ctl_elem_write(card, file, control);
963 snd_power_unlock(card);
964 if (result >= 0)
965 if (copy_to_user(_control, control, sizeof(*control)))
966 result = -EFAULT;
967 kfree(control);
968 return result;
969}
970
971static int snd_ctl_elem_lock(struct snd_ctl_file *file,
972 struct snd_ctl_elem_id __user *_id)
973{
974 struct snd_card *card = file->card;
975 struct snd_ctl_elem_id id;
976 struct snd_kcontrol *kctl;
977 struct snd_kcontrol_volatile *vd;
978 int result;
979
980 if (copy_from_user(&id, _id, sizeof(id)))
981 return -EFAULT;
982 down_write(&card->controls_rwsem);
983 kctl = snd_ctl_find_id(card, &id);
984 if (kctl == NULL) {
985 result = -ENOENT;
986 } else {
987 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
988 if (vd->owner != NULL)
989 result = -EBUSY;
990 else {
991 vd->owner = file;
992 result = 0;
993 }
994 }
995 up_write(&card->controls_rwsem);
996 return result;
997}
998
999static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
1000 struct snd_ctl_elem_id __user *_id)
1001{
1002 struct snd_card *card = file->card;
1003 struct snd_ctl_elem_id id;
1004 struct snd_kcontrol *kctl;
1005 struct snd_kcontrol_volatile *vd;
1006 int result;
1007
1008 if (copy_from_user(&id, _id, sizeof(id)))
1009 return -EFAULT;
1010 down_write(&card->controls_rwsem);
1011 kctl = snd_ctl_find_id(card, &id);
1012 if (kctl == NULL) {
1013 result = -ENOENT;
1014 } else {
1015 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
1016 if (vd->owner == NULL)
1017 result = -EINVAL;
1018 else if (vd->owner != file)
1019 result = -EPERM;
1020 else {
1021 vd->owner = NULL;
1022 result = 0;
1023 }
1024 }
1025 up_write(&card->controls_rwsem);
1026 return result;
1027}
1028
1029struct user_element {
1030 struct snd_ctl_elem_info info;
1031 struct snd_card *card;
1032 char *elem_data; /* element data */
1033 unsigned long elem_data_size; /* size of element data in bytes */
1034 void *tlv_data; /* TLV data */
1035 unsigned long tlv_data_size; /* TLV data size */
1036 void *priv_data; /* private data (like strings for enumerated type) */
1037};
1038
1039static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
1040 struct snd_ctl_elem_info *uinfo)
1041{
1042 struct user_element *ue = kcontrol->private_data;
1043 unsigned int offset;
1044
1045 offset = snd_ctl_get_ioff(kcontrol, &uinfo->id);
1046 *uinfo = ue->info;
1047 snd_ctl_build_ioff(&uinfo->id, kcontrol, offset);
1048
1049 return 0;
1050}
1051
1052static int snd_ctl_elem_user_enum_info(struct snd_kcontrol *kcontrol,
1053 struct snd_ctl_elem_info *uinfo)
1054{
1055 struct user_element *ue = kcontrol->private_data;
1056 const char *names;
1057 unsigned int item;
1058 unsigned int offset;
1059
1060 item = uinfo->value.enumerated.item;
1061
1062 offset = snd_ctl_get_ioff(kcontrol, &uinfo->id);
1063 *uinfo = ue->info;
1064 snd_ctl_build_ioff(&uinfo->id, kcontrol, offset);
1065
1066 item = min(item, uinfo->value.enumerated.items - 1);
1067 uinfo->value.enumerated.item = item;
1068
1069 names = ue->priv_data;
1070 for (; item > 0; --item)
1071 names += strlen(names) + 1;
1072 strcpy(uinfo->value.enumerated.name, names);
1073
1074 return 0;
1075}
1076
1077static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
1078 struct snd_ctl_elem_value *ucontrol)
1079{
1080 struct user_element *ue = kcontrol->private_data;
1081 unsigned int size = ue->elem_data_size;
1082 char *src = ue->elem_data +
1083 snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size;
1084
1085 mutex_lock(&ue->card->user_ctl_lock);
1086 memcpy(&ucontrol->value, src, size);
1087 mutex_unlock(&ue->card->user_ctl_lock);
1088 return 0;
1089}
1090
1091static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
1092 struct snd_ctl_elem_value *ucontrol)
1093{
1094 int change;
1095 struct user_element *ue = kcontrol->private_data;
1096 unsigned int size = ue->elem_data_size;
1097 char *dst = ue->elem_data +
1098 snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size;
1099
1100 mutex_lock(&ue->card->user_ctl_lock);
1101 change = memcmp(&ucontrol->value, dst, size) != 0;
1102 if (change)
1103 memcpy(dst, &ucontrol->value, size);
1104 mutex_unlock(&ue->card->user_ctl_lock);
1105 return change;
1106}
1107
1108static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
1109 int op_flag,
1110 unsigned int size,
1111 unsigned int __user *tlv)
1112{
1113 struct user_element *ue = kcontrol->private_data;
1114 int change = 0;
1115 void *new_data;
1116
1117 if (op_flag == SNDRV_CTL_TLV_OP_WRITE) {
1118 if (size > 1024 * 128) /* sane value */
1119 return -EINVAL;
1120
1121 new_data = memdup_user(tlv, size);
1122 if (IS_ERR(new_data))
1123 return PTR_ERR(new_data);
1124 mutex_lock(&ue->card->user_ctl_lock);
1125 change = ue->tlv_data_size != size;
1126 if (!change)
1127 change = memcmp(ue->tlv_data, new_data, size);
1128 kfree(ue->tlv_data);
1129 ue->tlv_data = new_data;
1130 ue->tlv_data_size = size;
1131 mutex_unlock(&ue->card->user_ctl_lock);
1132 } else {
1133 int ret = 0;
1134
1135 mutex_lock(&ue->card->user_ctl_lock);
1136 if (!ue->tlv_data_size || !ue->tlv_data) {
1137 ret = -ENXIO;
1138 goto err_unlock;
1139 }
1140 if (size < ue->tlv_data_size) {
1141 ret = -ENOSPC;
1142 goto err_unlock;
1143 }
1144 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
1145 ret = -EFAULT;
1146err_unlock:
1147 mutex_unlock(&ue->card->user_ctl_lock);
1148 if (ret)
1149 return ret;
1150 }
1151 return change;
1152}
1153
1154static int snd_ctl_elem_init_enum_names(struct user_element *ue)
1155{
1156 char *names, *p;
1157 size_t buf_len, name_len;
1158 unsigned int i;
1159 const uintptr_t user_ptrval = ue->info.value.enumerated.names_ptr;
1160
1161 if (ue->info.value.enumerated.names_length > 64 * 1024)
1162 return -EINVAL;
1163
1164 names = memdup_user((const void __user *)user_ptrval,
1165 ue->info.value.enumerated.names_length);
1166 if (IS_ERR(names))
1167 return PTR_ERR(names);
1168
1169 /* check that there are enough valid names */
1170 buf_len = ue->info.value.enumerated.names_length;
1171 p = names;
1172 for (i = 0; i < ue->info.value.enumerated.items; ++i) {
1173 name_len = strnlen(p, buf_len);
1174 if (name_len == 0 || name_len >= 64 || name_len == buf_len) {
1175 kfree(names);
1176 return -EINVAL;
1177 }
1178 p += name_len + 1;
1179 buf_len -= name_len + 1;
1180 }
1181
1182 ue->priv_data = names;
1183 ue->info.value.enumerated.names_ptr = 0;
1184
1185 return 0;
1186}
1187
1188static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
1189{
1190 struct user_element *ue = kcontrol->private_data;
1191
1192 kfree(ue->tlv_data);
1193 kfree(ue->priv_data);
1194 kfree(ue);
1195}
1196
1197static int snd_ctl_elem_add(struct snd_ctl_file *file,
1198 struct snd_ctl_elem_info *info, int replace)
1199{
1200 /* The capacity of struct snd_ctl_elem_value.value.*/
1201 static const unsigned int value_sizes[] = {
1202 [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = sizeof(long),
1203 [SNDRV_CTL_ELEM_TYPE_INTEGER] = sizeof(long),
1204 [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = sizeof(unsigned int),
1205 [SNDRV_CTL_ELEM_TYPE_BYTES] = sizeof(unsigned char),
1206 [SNDRV_CTL_ELEM_TYPE_IEC958] = sizeof(struct snd_aes_iec958),
1207 [SNDRV_CTL_ELEM_TYPE_INTEGER64] = sizeof(long long),
1208 };
1209 static const unsigned int max_value_counts[] = {
1210 [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = 128,
1211 [SNDRV_CTL_ELEM_TYPE_INTEGER] = 128,
1212 [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = 128,
1213 [SNDRV_CTL_ELEM_TYPE_BYTES] = 512,
1214 [SNDRV_CTL_ELEM_TYPE_IEC958] = 1,
1215 [SNDRV_CTL_ELEM_TYPE_INTEGER64] = 64,
1216 };
1217 struct snd_card *card = file->card;
1218 struct snd_kcontrol *kctl;
1219 unsigned int count;
1220 unsigned int access;
1221 long private_size;
1222 struct user_element *ue;
1223 unsigned int offset;
1224 int err;
1225
1226 if (!*info->id.name)
1227 return -EINVAL;
1228 if (strnlen(info->id.name, sizeof(info->id.name)) >= sizeof(info->id.name))
1229 return -EINVAL;
1230
1231 /* Delete a control to replace them if needed. */
1232 if (replace) {
1233 info->id.numid = 0;
1234 err = snd_ctl_remove_user_ctl(file, &info->id);
1235 if (err)
1236 return err;
1237 }
1238
1239 /*
1240 * The number of userspace controls are counted control by control,
1241 * not element by element.
1242 */
1243 if (card->user_ctl_count + 1 > MAX_USER_CONTROLS)
1244 return -ENOMEM;
1245
1246 /* Check the number of elements for this userspace control. */
1247 count = info->owner;
1248 if (count == 0)
1249 count = 1;
1250
1251 /* Arrange access permissions if needed. */
1252 access = info->access;
1253 if (access == 0)
1254 access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
1255 access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE |
1256 SNDRV_CTL_ELEM_ACCESS_INACTIVE |
1257 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE);
1258 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE)
1259 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1260 access |= SNDRV_CTL_ELEM_ACCESS_USER;
1261
1262 /*
1263 * Check information and calculate the size of data specific to
1264 * this userspace control.
1265 */
1266 if (info->type < SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
1267 info->type > SNDRV_CTL_ELEM_TYPE_INTEGER64)
1268 return -EINVAL;
1269 if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED &&
1270 info->value.enumerated.items == 0)
1271 return -EINVAL;
1272 if (info->count < 1 ||
1273 info->count > max_value_counts[info->type])
1274 return -EINVAL;
1275 private_size = value_sizes[info->type] * info->count;
1276
1277 /*
1278 * Keep memory object for this userspace control. After passing this
1279 * code block, the instance should be freed by snd_ctl_free_one().
1280 *
1281 * Note that these elements in this control are locked.
1282 */
1283 err = snd_ctl_new(&kctl, count, access, file);
1284 if (err < 0)
1285 return err;
1286 memcpy(&kctl->id, &info->id, sizeof(kctl->id));
1287 kctl->private_data = kzalloc(sizeof(struct user_element) + private_size * count,
1288 GFP_KERNEL);
1289 if (kctl->private_data == NULL) {
1290 kfree(kctl);
1291 return -ENOMEM;
1292 }
1293 kctl->private_free = snd_ctl_elem_user_free;
1294
1295 /* Set private data for this userspace control. */
1296 ue = (struct user_element *)kctl->private_data;
1297 ue->card = card;
1298 ue->info = *info;
1299 ue->info.access = 0;
1300 ue->elem_data = (char *)ue + sizeof(*ue);
1301 ue->elem_data_size = private_size;
1302 if (ue->info.type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) {
1303 err = snd_ctl_elem_init_enum_names(ue);
1304 if (err < 0) {
1305 snd_ctl_free_one(kctl);
1306 return err;
1307 }
1308 }
1309
1310 /* Set callback functions. */
1311 if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED)
1312 kctl->info = snd_ctl_elem_user_enum_info;
1313 else
1314 kctl->info = snd_ctl_elem_user_info;
1315 if (access & SNDRV_CTL_ELEM_ACCESS_READ)
1316 kctl->get = snd_ctl_elem_user_get;
1317 if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
1318 kctl->put = snd_ctl_elem_user_put;
1319 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE)
1320 kctl->tlv.c = snd_ctl_elem_user_tlv;
1321
1322 /* This function manage to free the instance on failure. */
1323 err = snd_ctl_add(card, kctl);
1324 if (err < 0)
1325 return err;
1326 offset = snd_ctl_get_ioff(kctl, &info->id);
1327 snd_ctl_build_ioff(&info->id, kctl, offset);
1328 /*
1329 * Here we cannot fill any field for the number of elements added by
1330 * this operation because there're no specific fields. The usage of
1331 * 'owner' field for this purpose may cause any bugs to userspace
1332 * applications because the field originally means PID of a process
1333 * which locks the element.
1334 */
1335
1336 down_write(&card->controls_rwsem);
1337 card->user_ctl_count++;
1338 up_write(&card->controls_rwsem);
1339
1340 return 0;
1341}
1342
1343static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1344 struct snd_ctl_elem_info __user *_info, int replace)
1345{
1346 struct snd_ctl_elem_info info;
1347 int err;
1348
1349 if (copy_from_user(&info, _info, sizeof(info)))
1350 return -EFAULT;
1351 err = snd_ctl_elem_add(file, &info, replace);
1352 if (err < 0)
1353 return err;
1354 if (copy_to_user(_info, &info, sizeof(info))) {
1355 snd_ctl_remove_user_ctl(file, &info.id);
1356 return -EFAULT;
1357 }
1358
1359 return 0;
1360}
1361
1362static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1363 struct snd_ctl_elem_id __user *_id)
1364{
1365 struct snd_ctl_elem_id id;
1366
1367 if (copy_from_user(&id, _id, sizeof(id)))
1368 return -EFAULT;
1369 return snd_ctl_remove_user_ctl(file, &id);
1370}
1371
1372static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
1373{
1374 int subscribe;
1375 if (get_user(subscribe, ptr))
1376 return -EFAULT;
1377 if (subscribe < 0) {
1378 subscribe = file->subscribed;
1379 if (put_user(subscribe, ptr))
1380 return -EFAULT;
1381 return 0;
1382 }
1383 if (subscribe) {
1384 file->subscribed = 1;
1385 return 0;
1386 } else if (file->subscribed) {
1387 snd_ctl_empty_read_queue(file);
1388 file->subscribed = 0;
1389 }
1390 return 0;
1391}
1392
1393static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1394 struct snd_ctl_tlv __user *_tlv,
1395 int op_flag)
1396{
1397 struct snd_card *card = file->card;
1398 struct snd_ctl_tlv tlv;
1399 struct snd_kcontrol *kctl;
1400 struct snd_kcontrol_volatile *vd;
1401 unsigned int len;
1402 int err = 0;
1403
1404 if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1405 return -EFAULT;
1406 if (tlv.length < sizeof(unsigned int) * 2)
1407 return -EINVAL;
1408 if (!tlv.numid)
1409 return -EINVAL;
1410 down_read(&card->controls_rwsem);
1411 kctl = snd_ctl_find_numid(card, tlv.numid);
1412 if (kctl == NULL) {
1413 err = -ENOENT;
1414 goto __kctl_end;
1415 }
1416 if (kctl->tlv.p == NULL) {
1417 err = -ENXIO;
1418 goto __kctl_end;
1419 }
1420 vd = &kctl->vd[tlv.numid - kctl->id.numid];
1421 if ((op_flag == SNDRV_CTL_TLV_OP_READ &&
1422 (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1423 (op_flag == SNDRV_CTL_TLV_OP_WRITE &&
1424 (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1425 (op_flag == SNDRV_CTL_TLV_OP_CMD &&
1426 (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
1427 err = -ENXIO;
1428 goto __kctl_end;
1429 }
1430 if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
1431 if (vd->owner != NULL && vd->owner != file) {
1432 err = -EPERM;
1433 goto __kctl_end;
1434 }
1435 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv);
1436 if (err > 0) {
1437 struct snd_ctl_elem_id id = kctl->id;
1438 up_read(&card->controls_rwsem);
1439 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &id);
1440 return 0;
1441 }
1442 } else {
1443 if (op_flag != SNDRV_CTL_TLV_OP_READ) {
1444 err = -ENXIO;
1445 goto __kctl_end;
1446 }
1447 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1448 if (tlv.length < len) {
1449 err = -ENOMEM;
1450 goto __kctl_end;
1451 }
1452 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1453 err = -EFAULT;
1454 }
1455 __kctl_end:
1456 up_read(&card->controls_rwsem);
1457 return err;
1458}
1459
1460static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1461{
1462 struct snd_ctl_file *ctl;
1463 struct snd_card *card;
1464 struct snd_kctl_ioctl *p;
1465 void __user *argp = (void __user *)arg;
1466 int __user *ip = argp;
1467 int err;
1468
1469 ctl = file->private_data;
1470 card = ctl->card;
1471 if (snd_BUG_ON(!card))
1472 return -ENXIO;
1473 switch (cmd) {
1474 case SNDRV_CTL_IOCTL_PVERSION:
1475 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1476 case SNDRV_CTL_IOCTL_CARD_INFO:
1477 return snd_ctl_card_info(card, ctl, cmd, argp);
1478 case SNDRV_CTL_IOCTL_ELEM_LIST:
1479 return snd_ctl_elem_list(card, argp);
1480 case SNDRV_CTL_IOCTL_ELEM_INFO:
1481 return snd_ctl_elem_info_user(ctl, argp);
1482 case SNDRV_CTL_IOCTL_ELEM_READ:
1483 return snd_ctl_elem_read_user(card, argp);
1484 case SNDRV_CTL_IOCTL_ELEM_WRITE:
1485 return snd_ctl_elem_write_user(ctl, argp);
1486 case SNDRV_CTL_IOCTL_ELEM_LOCK:
1487 return snd_ctl_elem_lock(ctl, argp);
1488 case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1489 return snd_ctl_elem_unlock(ctl, argp);
1490 case SNDRV_CTL_IOCTL_ELEM_ADD:
1491 return snd_ctl_elem_add_user(ctl, argp, 0);
1492 case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1493 return snd_ctl_elem_add_user(ctl, argp, 1);
1494 case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1495 return snd_ctl_elem_remove(ctl, argp);
1496 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1497 return snd_ctl_subscribe_events(ctl, ip);
1498 case SNDRV_CTL_IOCTL_TLV_READ:
1499 return snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_READ);
1500 case SNDRV_CTL_IOCTL_TLV_WRITE:
1501 return snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_WRITE);
1502 case SNDRV_CTL_IOCTL_TLV_COMMAND:
1503 return snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_CMD);
1504 case SNDRV_CTL_IOCTL_POWER:
1505 return -ENOPROTOOPT;
1506 case SNDRV_CTL_IOCTL_POWER_STATE:
1507#ifdef CONFIG_PM
1508 return put_user(card->power_state, ip) ? -EFAULT : 0;
1509#else
1510 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1511#endif
1512 }
1513 down_read(&snd_ioctl_rwsem);
1514 list_for_each_entry(p, &snd_control_ioctls, list) {
1515 err = p->fioctl(card, ctl, cmd, arg);
1516 if (err != -ENOIOCTLCMD) {
1517 up_read(&snd_ioctl_rwsem);
1518 return err;
1519 }
1520 }
1521 up_read(&snd_ioctl_rwsem);
1522 dev_dbg(card->dev, "unknown ioctl = 0x%x\n", cmd);
1523 return -ENOTTY;
1524}
1525
1526static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1527 size_t count, loff_t * offset)
1528{
1529 struct snd_ctl_file *ctl;
1530 int err = 0;
1531 ssize_t result = 0;
1532
1533 ctl = file->private_data;
1534 if (snd_BUG_ON(!ctl || !ctl->card))
1535 return -ENXIO;
1536 if (!ctl->subscribed)
1537 return -EBADFD;
1538 if (count < sizeof(struct snd_ctl_event))
1539 return -EINVAL;
1540 spin_lock_irq(&ctl->read_lock);
1541 while (count >= sizeof(struct snd_ctl_event)) {
1542 struct snd_ctl_event ev;
1543 struct snd_kctl_event *kev;
1544 while (list_empty(&ctl->events)) {
1545 wait_queue_t wait;
1546 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1547 err = -EAGAIN;
1548 goto __end_lock;
1549 }
1550 init_waitqueue_entry(&wait, current);
1551 add_wait_queue(&ctl->change_sleep, &wait);
1552 set_current_state(TASK_INTERRUPTIBLE);
1553 spin_unlock_irq(&ctl->read_lock);
1554 schedule();
1555 remove_wait_queue(&ctl->change_sleep, &wait);
1556 if (ctl->card->shutdown)
1557 return -ENODEV;
1558 if (signal_pending(current))
1559 return -ERESTARTSYS;
1560 spin_lock_irq(&ctl->read_lock);
1561 }
1562 kev = snd_kctl_event(ctl->events.next);
1563 ev.type = SNDRV_CTL_EVENT_ELEM;
1564 ev.data.elem.mask = kev->mask;
1565 ev.data.elem.id = kev->id;
1566 list_del(&kev->list);
1567 spin_unlock_irq(&ctl->read_lock);
1568 kfree(kev);
1569 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
1570 err = -EFAULT;
1571 goto __end;
1572 }
1573 spin_lock_irq(&ctl->read_lock);
1574 buffer += sizeof(struct snd_ctl_event);
1575 count -= sizeof(struct snd_ctl_event);
1576 result += sizeof(struct snd_ctl_event);
1577 }
1578 __end_lock:
1579 spin_unlock_irq(&ctl->read_lock);
1580 __end:
1581 return result > 0 ? result : err;
1582}
1583
1584static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1585{
1586 unsigned int mask;
1587 struct snd_ctl_file *ctl;
1588
1589 ctl = file->private_data;
1590 if (!ctl->subscribed)
1591 return 0;
1592 poll_wait(file, &ctl->change_sleep, wait);
1593
1594 mask = 0;
1595 if (!list_empty(&ctl->events))
1596 mask |= POLLIN | POLLRDNORM;
1597
1598 return mask;
1599}
1600
1601/*
1602 * register the device-specific control-ioctls.
1603 * called from each device manager like pcm.c, hwdep.c, etc.
1604 */
1605static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1606{
1607 struct snd_kctl_ioctl *pn;
1608
1609 pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
1610 if (pn == NULL)
1611 return -ENOMEM;
1612 pn->fioctl = fcn;
1613 down_write(&snd_ioctl_rwsem);
1614 list_add_tail(&pn->list, lists);
1615 up_write(&snd_ioctl_rwsem);
1616 return 0;
1617}
1618
1619/**
1620 * snd_ctl_register_ioctl - register the device-specific control-ioctls
1621 * @fcn: ioctl callback function
1622 *
1623 * called from each device manager like pcm.c, hwdep.c, etc.
1624 */
1625int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1626{
1627 return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1628}
1629EXPORT_SYMBOL(snd_ctl_register_ioctl);
1630
1631#ifdef CONFIG_COMPAT
1632/**
1633 * snd_ctl_register_ioctl_compat - register the device-specific 32bit compat
1634 * control-ioctls
1635 * @fcn: ioctl callback function
1636 */
1637int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1638{
1639 return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1640}
1641EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
1642#endif
1643
1644/*
1645 * de-register the device-specific control-ioctls.
1646 */
1647static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1648 struct list_head *lists)
1649{
1650 struct snd_kctl_ioctl *p;
1651
1652 if (snd_BUG_ON(!fcn))
1653 return -EINVAL;
1654 down_write(&snd_ioctl_rwsem);
1655 list_for_each_entry(p, lists, list) {
1656 if (p->fioctl == fcn) {
1657 list_del(&p->list);
1658 up_write(&snd_ioctl_rwsem);
1659 kfree(p);
1660 return 0;
1661 }
1662 }
1663 up_write(&snd_ioctl_rwsem);
1664 snd_BUG();
1665 return -EINVAL;
1666}
1667
1668/**
1669 * snd_ctl_unregister_ioctl - de-register the device-specific control-ioctls
1670 * @fcn: ioctl callback function to unregister
1671 */
1672int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1673{
1674 return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1675}
1676EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1677
1678#ifdef CONFIG_COMPAT
1679/**
1680 * snd_ctl_unregister_ioctl - de-register the device-specific compat 32bit
1681 * control-ioctls
1682 * @fcn: ioctl callback function to unregister
1683 */
1684int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1685{
1686 return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1687}
1688EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
1689#endif
1690
1691static int snd_ctl_fasync(int fd, struct file * file, int on)
1692{
1693 struct snd_ctl_file *ctl;
1694
1695 ctl = file->private_data;
1696 return fasync_helper(fd, file, on, &ctl->fasync);
1697}
1698
1699/* return the preferred subdevice number if already assigned;
1700 * otherwise return -1
1701 */
1702int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type)
1703{
1704 struct snd_ctl_file *kctl;
1705 int subdevice = -1;
1706
1707 read_lock(&card->ctl_files_rwlock);
1708 list_for_each_entry(kctl, &card->ctl_files, list) {
1709 if (kctl->pid == task_pid(current)) {
1710 subdevice = kctl->preferred_subdevice[type];
1711 if (subdevice != -1)
1712 break;
1713 }
1714 }
1715 read_unlock(&card->ctl_files_rwlock);
1716 return subdevice;
1717}
1718EXPORT_SYMBOL_GPL(snd_ctl_get_preferred_subdevice);
1719
1720/*
1721 * ioctl32 compat
1722 */
1723#ifdef CONFIG_COMPAT
1724#include "control_compat.c"
1725#else
1726#define snd_ctl_ioctl_compat NULL
1727#endif
1728
1729/*
1730 * INIT PART
1731 */
1732
1733static const struct file_operations snd_ctl_f_ops =
1734{
1735 .owner = THIS_MODULE,
1736 .read = snd_ctl_read,
1737 .open = snd_ctl_open,
1738 .release = snd_ctl_release,
1739 .llseek = no_llseek,
1740 .poll = snd_ctl_poll,
1741 .unlocked_ioctl = snd_ctl_ioctl,
1742 .compat_ioctl = snd_ctl_ioctl_compat,
1743 .fasync = snd_ctl_fasync,
1744};
1745
1746/*
1747 * registration of the control device
1748 */
1749static int snd_ctl_dev_register(struct snd_device *device)
1750{
1751 struct snd_card *card = device->device_data;
1752
1753 return snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1754 &snd_ctl_f_ops, card, &card->ctl_dev);
1755}
1756
1757/*
1758 * disconnection of the control device
1759 */
1760static int snd_ctl_dev_disconnect(struct snd_device *device)
1761{
1762 struct snd_card *card = device->device_data;
1763 struct snd_ctl_file *ctl;
1764
1765 read_lock(&card->ctl_files_rwlock);
1766 list_for_each_entry(ctl, &card->ctl_files, list) {
1767 wake_up(&ctl->change_sleep);
1768 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1769 }
1770 read_unlock(&card->ctl_files_rwlock);
1771
1772 return snd_unregister_device(&card->ctl_dev);
1773}
1774
1775/*
1776 * free all controls
1777 */
1778static int snd_ctl_dev_free(struct snd_device *device)
1779{
1780 struct snd_card *card = device->device_data;
1781 struct snd_kcontrol *control;
1782
1783 down_write(&card->controls_rwsem);
1784 while (!list_empty(&card->controls)) {
1785 control = snd_kcontrol(card->controls.next);
1786 snd_ctl_remove(card, control);
1787 }
1788 up_write(&card->controls_rwsem);
1789 put_device(&card->ctl_dev);
1790 return 0;
1791}
1792
1793/*
1794 * create control core:
1795 * called from init.c
1796 */
1797int snd_ctl_create(struct snd_card *card)
1798{
1799 static struct snd_device_ops ops = {
1800 .dev_free = snd_ctl_dev_free,
1801 .dev_register = snd_ctl_dev_register,
1802 .dev_disconnect = snd_ctl_dev_disconnect,
1803 };
1804 int err;
1805
1806 if (snd_BUG_ON(!card))
1807 return -ENXIO;
1808 if (snd_BUG_ON(card->number < 0 || card->number >= SNDRV_CARDS))
1809 return -ENXIO;
1810
1811 snd_device_initialize(&card->ctl_dev, card);
1812 dev_set_name(&card->ctl_dev, "controlC%d", card->number);
1813
1814 err = snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1815 if (err < 0)
1816 put_device(&card->ctl_dev);
1817 return err;
1818}
1819
1820/*
1821 * Frequently used control callbacks/helpers
1822 */
1823
1824/**
1825 * snd_ctl_boolean_mono_info - Helper function for a standard boolean info
1826 * callback with a mono channel
1827 * @kcontrol: the kcontrol instance
1828 * @uinfo: info to store
1829 *
1830 * This is a function that can be used as info callback for a standard
1831 * boolean control with a single mono channel.
1832 */
1833int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1834 struct snd_ctl_elem_info *uinfo)
1835{
1836 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1837 uinfo->count = 1;
1838 uinfo->value.integer.min = 0;
1839 uinfo->value.integer.max = 1;
1840 return 0;
1841}
1842EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1843
1844/**
1845 * snd_ctl_boolean_stereo_info - Helper function for a standard boolean info
1846 * callback with stereo two channels
1847 * @kcontrol: the kcontrol instance
1848 * @uinfo: info to store
1849 *
1850 * This is a function that can be used as info callback for a standard
1851 * boolean control with stereo two channels.
1852 */
1853int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1854 struct snd_ctl_elem_info *uinfo)
1855{
1856 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1857 uinfo->count = 2;
1858 uinfo->value.integer.min = 0;
1859 uinfo->value.integer.max = 1;
1860 return 0;
1861}
1862EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);
1863
1864/**
1865 * snd_ctl_enum_info - fills the info structure for an enumerated control
1866 * @info: the structure to be filled
1867 * @channels: the number of the control's channels; often one
1868 * @items: the number of control values; also the size of @names
1869 * @names: an array containing the names of all control values
1870 *
1871 * Sets all required fields in @info to their appropriate values.
1872 * If the control's accessibility is not the default (readable and writable),
1873 * the caller has to fill @info->access.
1874 *
1875 * Return: Zero.
1876 */
1877int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
1878 unsigned int items, const char *const names[])
1879{
1880 info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
1881 info->count = channels;
1882 info->value.enumerated.items = items;
1883 if (!items)
1884 return 0;
1885 if (info->value.enumerated.item >= items)
1886 info->value.enumerated.item = items - 1;
1887 WARN(strlen(names[info->value.enumerated.item]) >= sizeof(info->value.enumerated.name),
1888 "ALSA: too long item name '%s'\n",
1889 names[info->value.enumerated.item]);
1890 strlcpy(info->value.enumerated.name,
1891 names[info->value.enumerated.item],
1892 sizeof(info->value.enumerated.name));
1893 return 0;
1894}
1895EXPORT_SYMBOL(snd_ctl_enum_info);
1/*
2 * Routines for driver control interface
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22#include <linux/threads.h>
23#include <linux/interrupt.h>
24#include <linux/module.h>
25#include <linux/slab.h>
26#include <linux/vmalloc.h>
27#include <linux/time.h>
28#include <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);