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