2 * Routines for driver control interface
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
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.
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.
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
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>
32 /* max number of user-defined controls */
33 #define MAX_USER_CONTROLS 32
34 #define MAX_CONTROL_COUNT 1028
36 struct snd_kctl_ioctl
{
37 struct list_head list
; /* list of all ioctls */
38 snd_kctl_ioctl_func_t fioctl
;
41 static DECLARE_RWSEM(snd_ioctl_rwsem
);
42 static LIST_HEAD(snd_control_ioctls
);
44 static LIST_HEAD(snd_control_compat_ioctls
);
47 static int snd_ctl_open(struct inode
*inode
, struct file
*file
)
50 struct snd_card
*card
;
51 struct snd_ctl_file
*ctl
;
54 err
= nonseekable_open(inode
, file
);
58 card
= snd_lookup_minor_data(iminor(inode
), SNDRV_DEVICE_TYPE_CONTROL
);
63 err
= snd_card_file_add(card
, file
);
68 if (!try_module_get(card
->module
)) {
72 ctl
= kzalloc(sizeof(*ctl
), GFP_KERNEL
);
77 INIT_LIST_HEAD(&ctl
->events
);
78 init_waitqueue_head(&ctl
->change_sleep
);
79 spin_lock_init(&ctl
->read_lock
);
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
);
91 module_put(card
->module
);
93 snd_card_file_remove(card
, file
);
98 static void snd_ctl_empty_read_queue(struct snd_ctl_file
* ctl
)
101 struct snd_kctl_event
*cread
;
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
);
109 spin_unlock_irqrestore(&ctl
->read_lock
, flags
);
112 static int snd_ctl_release(struct inode
*inode
, struct file
*file
)
115 struct snd_card
*card
;
116 struct snd_ctl_file
*ctl
;
117 struct snd_kcontrol
*control
;
120 ctl
= file
->private_data
;
121 file
->private_data
= NULL
;
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
);
135 module_put(card
->module
);
136 snd_card_file_remove(card
, file
);
140 void snd_ctl_notify(struct snd_card
*card
, unsigned int mask
,
141 struct snd_ctl_elem_id
*id
)
144 struct snd_ctl_file
*ctl
;
145 struct snd_kctl_event
*ev
;
147 if (snd_BUG_ON(!card
|| !id
))
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
++;
153 list_for_each_entry(ctl
, &card
->ctl_files
, list
) {
154 if (!ctl
->subscribed
)
156 spin_lock_irqsave(&ctl
->read_lock
, flags
);
157 list_for_each_entry(ev
, &ctl
->events
, list
) {
158 if (ev
->id
.numid
== id
->numid
) {
163 ev
= kzalloc(sizeof(*ev
), GFP_ATOMIC
);
167 list_add_tail(&ev
->list
, &ctl
->events
);
169 snd_printk(KERN_ERR
"No memory available to allocate event\n");
172 wake_up(&ctl
->change_sleep
);
173 spin_unlock_irqrestore(&ctl
->read_lock
, flags
);
174 kill_fasync(&ctl
->fasync
, SIGIO
, POLL_IN
);
176 read_unlock(&card
->ctl_files_rwlock
);
179 EXPORT_SYMBOL(snd_ctl_notify
);
182 * snd_ctl_new - create a control instance from the template
183 * @control: the control template
184 * @access: the default control access
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).
189 * Returns the pointer of the new instance, or NULL on failure.
191 static struct snd_kcontrol
*snd_ctl_new(struct snd_kcontrol
*control
,
194 struct snd_kcontrol
*kctl
;
197 if (snd_BUG_ON(!control
|| !control
->count
))
200 if (control
->count
> MAX_CONTROL_COUNT
)
203 kctl
= kzalloc(sizeof(*kctl
) + sizeof(struct snd_kcontrol_volatile
) * control
->count
, GFP_KERNEL
);
205 snd_printk(KERN_ERR
"Cannot allocate control instance\n");
209 for (idx
= 0; idx
< kctl
->count
; idx
++)
210 kctl
->vd
[idx
].access
= access
;
215 * snd_ctl_new1 - create a control instance from the template
216 * @ncontrol: the initialization record
217 * @private_data: the private data to set
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.
223 * Returns the pointer of the newly generated instance, or NULL on failure.
225 struct snd_kcontrol
*snd_ctl_new1(const struct snd_kcontrol_new
*ncontrol
,
228 struct snd_kcontrol kctl
;
231 if (snd_BUG_ON(!ncontrol
|| !ncontrol
->info
))
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
);
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
);
261 EXPORT_SYMBOL(snd_ctl_new1
);
264 * snd_ctl_free_one - release the control instance
265 * @kcontrol: the control instance
267 * Releases the control instance created via snd_ctl_new()
269 * Don't call this after the control was added to the card.
271 void snd_ctl_free_one(struct snd_kcontrol
*kcontrol
)
274 if (kcontrol
->private_free
)
275 kcontrol
->private_free(kcontrol
);
280 EXPORT_SYMBOL(snd_ctl_free_one
);
282 static bool snd_ctl_remove_numid_conflict(struct snd_card
*card
,
285 struct snd_kcontrol
*kctl
;
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;
297 static int snd_ctl_find_hole(struct snd_card
*card
, unsigned int count
)
299 unsigned int iter
= 100000;
301 while (snd_ctl_remove_numid_conflict(card
, count
)) {
303 /* this situation is very unlikely */
304 snd_printk(KERN_ERR
"unable to allocate new control numid\n");
312 * snd_ctl_add - add the control instance to the card
313 * @card: the card instance
314 * @kcontrol: the control instance to add
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.
320 * Returns zero if successful, or a negative error code on failure.
322 * It frees automatically the control which cannot be added.
324 int snd_ctl_add(struct snd_card
*card
, struct snd_kcontrol
*kcontrol
)
326 struct snd_ctl_elem_id id
;
332 if (snd_BUG_ON(!card
|| !kcontrol
->info
))
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",
347 if (snd_ctl_find_hole(card
, kcontrol
->count
) < 0) {
348 up_write(&card
->controls_rwsem
);
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
);
362 snd_ctl_free_one(kcontrol
);
366 EXPORT_SYMBOL(snd_ctl_add
);
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
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.
378 * Returns zero if successful, or a negative error code on failure.
380 * It frees automatically the control which cannot be added or replaced.
382 int snd_ctl_replace(struct snd_card
*card
, struct snd_kcontrol
*kcontrol
,
385 struct snd_ctl_elem_id id
;
387 struct snd_kcontrol
*old
;
392 if (snd_BUG_ON(!card
|| !kcontrol
->info
)) {
397 down_write(&card
->controls_rwsem
);
398 old
= snd_ctl_find_id(card
, &id
);
402 up_write(&card
->controls_rwsem
);
406 ret
= snd_ctl_remove(card
, old
);
408 up_write(&card
->controls_rwsem
);
412 if (snd_ctl_find_hole(card
, kcontrol
->count
) < 0) {
413 up_write(&card
->controls_rwsem
);
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
);
427 snd_ctl_free_one(kcontrol
);
430 EXPORT_SYMBOL(snd_ctl_replace
);
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
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).
441 * Returns 0 if successful, or a negative error code on failure.
443 int snd_ctl_remove(struct snd_card
*card
, struct snd_kcontrol
*kcontrol
)
445 struct snd_ctl_elem_id id
;
448 if (snd_BUG_ON(!card
|| !kcontrol
))
450 list_del(&kcontrol
->list
);
451 card
->controls_count
-= kcontrol
->count
;
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
);
459 EXPORT_SYMBOL(snd_ctl_remove
);
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
466 * Finds the control instance with the given id, removes it from the
467 * card list and releases it.
469 * Returns 0 if successful, or a negative error code on failure.
471 int snd_ctl_remove_id(struct snd_card
*card
, struct snd_ctl_elem_id
*id
)
473 struct snd_kcontrol
*kctl
;
476 down_write(&card
->controls_rwsem
);
477 kctl
= snd_ctl_find_id(card
, id
);
479 up_write(&card
->controls_rwsem
);
482 ret
= snd_ctl_remove(card
, kctl
);
483 up_write(&card
->controls_rwsem
);
487 EXPORT_SYMBOL(snd_ctl_remove_id
);
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
494 * Finds the control instance with the given id, removes it from the
495 * card list and releases it.
497 * Returns 0 if successful, or a negative error code on failure.
499 static int snd_ctl_remove_user_ctl(struct snd_ctl_file
* file
,
500 struct snd_ctl_elem_id
*id
)
502 struct snd_card
*card
= file
->card
;
503 struct snd_kcontrol
*kctl
;
506 down_write(&card
->controls_rwsem
);
507 kctl
= snd_ctl_find_id(card
, id
);
512 if (!(kctl
->vd
[0].access
& SNDRV_CTL_ELEM_ACCESS_USER
)) {
516 for (idx
= 0; idx
< kctl
->count
; idx
++)
517 if (kctl
->vd
[idx
].owner
!= NULL
&& kctl
->vd
[idx
].owner
!= file
) {
521 ret
= snd_ctl_remove(card
, kctl
);
524 card
->user_ctl_count
--;
526 up_write(&card
->controls_rwsem
);
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
536 * Finds the control instance with the given id, and activate or
537 * inactivate the control together with notification, if changed.
539 * Returns 0 if unchanged, 1 if changed, or a negative error code on failure.
541 int snd_ctl_activate_id(struct snd_card
*card
, struct snd_ctl_elem_id
*id
,
544 struct snd_kcontrol
*kctl
;
545 struct snd_kcontrol_volatile
*vd
;
546 unsigned int index_offset
;
549 down_write(&card
->controls_rwsem
);
550 kctl
= snd_ctl_find_id(card
, id
);
555 index_offset
= snd_ctl_get_ioff(kctl
, &kctl
->id
);
556 vd
= &kctl
->vd
[index_offset
];
559 if (!(vd
->access
& SNDRV_CTL_ELEM_ACCESS_INACTIVE
))
561 vd
->access
&= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE
;
563 if (vd
->access
& SNDRV_CTL_ELEM_ACCESS_INACTIVE
)
565 vd
->access
|= SNDRV_CTL_ELEM_ACCESS_INACTIVE
;
569 up_write(&card
->controls_rwsem
);
571 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_INFO
, id
);
574 EXPORT_SYMBOL_GPL(snd_ctl_activate_id
);
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
582 * Finds the control with the old id from the card, and replaces the
583 * id with the new one.
585 * Returns zero if successful, or a negative error code on failure.
587 int snd_ctl_rename_id(struct snd_card
*card
, struct snd_ctl_elem_id
*src_id
,
588 struct snd_ctl_elem_id
*dst_id
)
590 struct snd_kcontrol
*kctl
;
592 down_write(&card
->controls_rwsem
);
593 kctl
= snd_ctl_find_id(card
, src_id
);
595 up_write(&card
->controls_rwsem
);
599 kctl
->id
.numid
= card
->last_numid
+ 1;
600 card
->last_numid
+= kctl
->count
;
601 up_write(&card
->controls_rwsem
);
605 EXPORT_SYMBOL(snd_ctl_rename_id
);
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
612 * Finds the control instance with the given number-id from the card.
614 * Returns the pointer of the instance if found, or NULL if not.
616 * The caller must down card->controls_rwsem before calling this function
617 * (if the race condition can happen).
619 struct snd_kcontrol
*snd_ctl_find_numid(struct snd_card
*card
, unsigned int numid
)
621 struct snd_kcontrol
*kctl
;
623 if (snd_BUG_ON(!card
|| !numid
))
625 list_for_each_entry(kctl
, &card
->controls
, list
) {
626 if (kctl
->id
.numid
<= numid
&& kctl
->id
.numid
+ kctl
->count
> numid
)
632 EXPORT_SYMBOL(snd_ctl_find_numid
);
635 * snd_ctl_find_id - find the control instance with the given id
636 * @card: the card instance
637 * @id: the id to search
639 * Finds the control instance with the given id from the card.
641 * Returns the pointer of the instance if found, or NULL if not.
643 * The caller must down card->controls_rwsem before calling this function
644 * (if the race condition can happen).
646 struct snd_kcontrol
*snd_ctl_find_id(struct snd_card
*card
,
647 struct snd_ctl_elem_id
*id
)
649 struct snd_kcontrol
*kctl
;
651 if (snd_BUG_ON(!card
|| !id
))
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
)
658 if (kctl
->id
.device
!= id
->device
)
660 if (kctl
->id
.subdevice
!= id
->subdevice
)
662 if (strncmp(kctl
->id
.name
, id
->name
, sizeof(kctl
->id
.name
)))
664 if (kctl
->id
.index
> id
->index
)
666 if (kctl
->id
.index
+ kctl
->count
<= id
->index
)
673 EXPORT_SYMBOL(snd_ctl_find_id
);
675 static int snd_ctl_card_info(struct snd_card
*card
, struct snd_ctl_file
* ctl
,
676 unsigned int cmd
, void __user
*arg
)
678 struct snd_ctl_card_info
*info
;
680 info
= kzalloc(sizeof(*info
), GFP_KERNEL
);
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
))) {
700 static int snd_ctl_elem_list(struct snd_card
*card
,
701 struct snd_ctl_elem_list __user
*_list
)
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
;
709 if (copy_from_user(&list
, _list
, sizeof(list
)))
711 offset
= list
.offset
;
713 /* try limit maximum space */
717 /* allocate temporary buffer for atomic operation */
718 dst
= vmalloc(space
* sizeof(struct snd_ctl_elem_id
));
721 down_read(&card
->controls_rwsem
);
722 list
.count
= card
->controls_count
;
723 plist
= card
->controls
.next
;
724 while (plist
!= &card
->controls
) {
727 kctl
= snd_kcontrol(plist
);
728 if (offset
< kctl
->count
)
730 offset
-= kctl
->count
;
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
);
746 up_read(&card
->controls_rwsem
);
748 copy_to_user(list
.pids
, dst
,
749 list
.used
* sizeof(struct snd_ctl_elem_id
))) {
755 down_read(&card
->controls_rwsem
);
756 list
.count
= card
->controls_count
;
757 up_read(&card
->controls_rwsem
);
759 if (copy_to_user(_list
, &list
, sizeof(list
)))
764 static int snd_ctl_elem_info(struct snd_ctl_file
*ctl
,
765 struct snd_ctl_elem_info
*info
)
767 struct snd_card
*card
= ctl
->card
;
768 struct snd_kcontrol
*kctl
;
769 struct snd_kcontrol_volatile
*vd
;
770 unsigned int index_offset
;
773 down_read(&card
->controls_rwsem
);
774 kctl
= snd_ctl_find_id(card
, &info
->id
);
776 up_read(&card
->controls_rwsem
);
779 #ifdef CONFIG_SND_DEBUG
782 result
= kctl
->info(kctl
, info
);
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
;
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
);
798 up_read(&card
->controls_rwsem
);
802 static int snd_ctl_elem_info_user(struct snd_ctl_file
*ctl
,
803 struct snd_ctl_elem_info __user
*_info
)
805 struct snd_ctl_elem_info info
;
808 if (copy_from_user(&info
, _info
, sizeof(info
)))
810 snd_power_lock(ctl
->card
);
811 result
= snd_power_wait(ctl
->card
, SNDRV_CTL_POWER_D0
);
813 result
= snd_ctl_elem_info(ctl
, &info
);
814 snd_power_unlock(ctl
->card
);
816 if (copy_to_user(_info
, &info
, sizeof(info
)))
821 static int snd_ctl_elem_read(struct snd_card
*card
,
822 struct snd_ctl_elem_value
*control
)
824 struct snd_kcontrol
*kctl
;
825 struct snd_kcontrol_volatile
*vd
;
826 unsigned int index_offset
;
829 down_read(&card
->controls_rwsem
);
830 kctl
= snd_ctl_find_id(card
, &control
->id
);
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
) &&
838 snd_ctl_build_ioff(&control
->id
, kctl
, index_offset
);
839 result
= kctl
->get(kctl
, control
);
843 up_read(&card
->controls_rwsem
);
847 static int snd_ctl_elem_read_user(struct snd_card
*card
,
848 struct snd_ctl_elem_value __user
*_control
)
850 struct snd_ctl_elem_value
*control
;
853 control
= memdup_user(_control
, sizeof(*control
));
855 return PTR_ERR(control
);
857 snd_power_lock(card
);
858 result
= snd_power_wait(card
, SNDRV_CTL_POWER_D0
);
860 result
= snd_ctl_elem_read(card
, control
);
861 snd_power_unlock(card
);
863 if (copy_to_user(_control
, control
, sizeof(*control
)))
869 static int snd_ctl_elem_write(struct snd_card
*card
, struct snd_ctl_file
*file
,
870 struct snd_ctl_elem_value
*control
)
872 struct snd_kcontrol
*kctl
;
873 struct snd_kcontrol_volatile
*vd
;
874 unsigned int index_offset
;
877 down_read(&card
->controls_rwsem
);
878 kctl
= snd_ctl_find_id(card
, &control
->id
);
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
) ||
886 (file
&& vd
->owner
&& vd
->owner
!= file
)) {
889 snd_ctl_build_ioff(&control
->id
, kctl
, index_offset
);
890 result
= kctl
->put(kctl
, control
);
893 up_read(&card
->controls_rwsem
);
894 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_VALUE
,
899 up_read(&card
->controls_rwsem
);
903 static int snd_ctl_elem_write_user(struct snd_ctl_file
*file
,
904 struct snd_ctl_elem_value __user
*_control
)
906 struct snd_ctl_elem_value
*control
;
907 struct snd_card
*card
;
910 control
= memdup_user(_control
, sizeof(*control
));
912 return PTR_ERR(control
);
915 snd_power_lock(card
);
916 result
= snd_power_wait(card
, SNDRV_CTL_POWER_D0
);
918 result
= snd_ctl_elem_write(card
, file
, control
);
919 snd_power_unlock(card
);
921 if (copy_to_user(_control
, control
, sizeof(*control
)))
927 static int snd_ctl_elem_lock(struct snd_ctl_file
*file
,
928 struct snd_ctl_elem_id __user
*_id
)
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
;
936 if (copy_from_user(&id
, _id
, sizeof(id
)))
938 down_write(&card
->controls_rwsem
);
939 kctl
= snd_ctl_find_id(card
, &id
);
943 vd
= &kctl
->vd
[snd_ctl_get_ioff(kctl
, &id
)];
944 if (vd
->owner
!= NULL
)
951 up_write(&card
->controls_rwsem
);
955 static int snd_ctl_elem_unlock(struct snd_ctl_file
*file
,
956 struct snd_ctl_elem_id __user
*_id
)
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
;
964 if (copy_from_user(&id
, _id
, sizeof(id
)))
966 down_write(&card
->controls_rwsem
);
967 kctl
= snd_ctl_find_id(card
, &id
);
971 vd
= &kctl
->vd
[snd_ctl_get_ioff(kctl
, &id
)];
972 if (vd
->owner
== NULL
)
974 else if (vd
->owner
!= file
)
981 up_write(&card
->controls_rwsem
);
985 struct 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 */
995 static int snd_ctl_elem_user_info(struct snd_kcontrol
*kcontrol
,
996 struct snd_ctl_elem_info
*uinfo
)
998 struct user_element
*ue
= kcontrol
->private_data
;
1004 static int snd_ctl_elem_user_get(struct snd_kcontrol
*kcontrol
,
1005 struct snd_ctl_elem_value
*ucontrol
)
1007 struct user_element
*ue
= kcontrol
->private_data
;
1009 memcpy(&ucontrol
->value
, ue
->elem_data
, ue
->elem_data_size
);
1013 static int snd_ctl_elem_user_put(struct snd_kcontrol
*kcontrol
,
1014 struct snd_ctl_elem_value
*ucontrol
)
1017 struct user_element
*ue
= kcontrol
->private_data
;
1019 change
= memcmp(&ucontrol
->value
, ue
->elem_data
, ue
->elem_data_size
) != 0;
1021 memcpy(ue
->elem_data
, &ucontrol
->value
, ue
->elem_data_size
);
1025 static int snd_ctl_elem_user_tlv(struct snd_kcontrol
*kcontrol
,
1028 unsigned int __user
*tlv
)
1030 struct user_element
*ue
= kcontrol
->private_data
;
1035 if (size
> 1024 * 128) /* sane value */
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
;
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
;
1048 if (! ue
->tlv_data_size
|| ! ue
->tlv_data
)
1050 if (size
< ue
->tlv_data_size
)
1052 if (copy_to_user(tlv
, ue
->tlv_data
, ue
->tlv_data_size
))
1058 static void snd_ctl_elem_user_free(struct snd_kcontrol
*kcontrol
)
1060 struct user_element
*ue
= kcontrol
->private_data
;
1062 kfree(ue
->tlv_data
);
1066 static int snd_ctl_elem_add(struct snd_ctl_file
*file
,
1067 struct snd_ctl_elem_info
*info
, int replace
)
1069 struct snd_card
*card
= file
->card
;
1070 struct snd_kcontrol kctl
, *_kctl
;
1071 unsigned int access
;
1073 struct user_element
*ue
;
1076 if (card
->user_ctl_count
>= MAX_USER_CONTROLS
)
1078 if (info
->count
< 1)
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
));
1085 memset(&kctl
, 0, sizeof(kctl
));
1086 down_write(&card
->controls_rwsem
);
1087 _kctl
= snd_ctl_find_id(card
, &info
->id
);
1091 err
= snd_ctl_remove(card
, _kctl
);
1098 up_write(&card
->controls_rwsem
);
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
;
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)
1120 case SNDRV_CTL_ELEM_TYPE_INTEGER64
:
1121 private_size
= sizeof(long long);
1122 if (info
->count
> 64)
1125 case SNDRV_CTL_ELEM_TYPE_BYTES
:
1126 private_size
= sizeof(unsigned char);
1127 if (info
->count
> 512)
1130 case SNDRV_CTL_ELEM_TYPE_IEC958
:
1131 private_size
= sizeof(struct snd_aes_iec958
);
1132 if (info
->count
!= 1)
1138 private_size
*= info
->count
;
1139 ue
= kzalloc(sizeof(struct user_element
) + private_size
, GFP_KERNEL
);
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
) {
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
);
1159 down_write(&card
->controls_rwsem
);
1160 card
->user_ctl_count
++;
1161 up_write(&card
->controls_rwsem
);
1166 static int snd_ctl_elem_add_user(struct snd_ctl_file
*file
,
1167 struct snd_ctl_elem_info __user
*_info
, int replace
)
1169 struct snd_ctl_elem_info info
;
1170 if (copy_from_user(&info
, _info
, sizeof(info
)))
1172 return snd_ctl_elem_add(file
, &info
, replace
);
1175 static int snd_ctl_elem_remove(struct snd_ctl_file
*file
,
1176 struct snd_ctl_elem_id __user
*_id
)
1178 struct snd_ctl_elem_id id
;
1180 if (copy_from_user(&id
, _id
, sizeof(id
)))
1182 return snd_ctl_remove_user_ctl(file
, &id
);
1185 static int snd_ctl_subscribe_events(struct snd_ctl_file
*file
, int __user
*ptr
)
1188 if (get_user(subscribe
, ptr
))
1190 if (subscribe
< 0) {
1191 subscribe
= file
->subscribed
;
1192 if (put_user(subscribe
, ptr
))
1197 file
->subscribed
= 1;
1199 } else if (file
->subscribed
) {
1200 snd_ctl_empty_read_queue(file
);
1201 file
->subscribed
= 0;
1206 static int snd_ctl_tlv_ioctl(struct snd_ctl_file
*file
,
1207 struct snd_ctl_tlv __user
*_tlv
,
1210 struct snd_card
*card
= file
->card
;
1211 struct snd_ctl_tlv tlv
;
1212 struct snd_kcontrol
*kctl
;
1213 struct snd_kcontrol_volatile
*vd
;
1217 if (copy_from_user(&tlv
, _tlv
, sizeof(tlv
)))
1219 if (tlv
.length
< sizeof(unsigned int) * 2)
1221 down_read(&card
->controls_rwsem
);
1222 kctl
= snd_ctl_find_numid(card
, tlv
.numid
);
1227 if (kctl
->tlv
.p
== NULL
) {
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)) {
1238 if (vd
->access
& SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK
) {
1239 if (vd
->owner
!= NULL
&& vd
->owner
!= file
) {
1243 err
= kctl
->tlv
.c(kctl
, op_flag
, tlv
.length
, _tlv
->tlv
);
1245 up_read(&card
->controls_rwsem
);
1246 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_TLV
, &kctl
->id
);
1254 len
= kctl
->tlv
.p
[1] + 2 * sizeof(unsigned int);
1255 if (tlv
.length
< len
) {
1259 if (copy_to_user(_tlv
->tlv
, kctl
->tlv
.p
, len
))
1263 up_read(&card
->controls_rwsem
);
1267 static long snd_ctl_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
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
;
1276 ctl
= file
->private_data
;
1278 if (snd_BUG_ON(!card
))
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
:
1315 return put_user(card
->power_state
, ip
) ? -EFAULT
: 0;
1317 return put_user(SNDRV_CTL_POWER_D0
, ip
) ? -EFAULT
: 0;
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
);
1328 up_read(&snd_ioctl_rwsem
);
1329 snd_printdd("unknown ioctl = 0x%x\n", cmd
);
1333 static ssize_t
snd_ctl_read(struct file
*file
, char __user
*buffer
,
1334 size_t count
, loff_t
* offset
)
1336 struct snd_ctl_file
*ctl
;
1340 ctl
= file
->private_data
;
1341 if (snd_BUG_ON(!ctl
|| !ctl
->card
))
1343 if (!ctl
->subscribed
)
1345 if (count
< sizeof(struct snd_ctl_event
))
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
)) {
1353 if ((file
->f_flags
& O_NONBLOCK
) != 0 || result
> 0) {
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
);
1362 remove_wait_queue(&ctl
->change_sleep
, &wait
);
1363 if (signal_pending(current
))
1364 return -ERESTARTSYS
;
1365 spin_lock_irq(&ctl
->read_lock
);
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
);
1374 if (copy_to_user(buffer
, &ev
, sizeof(struct snd_ctl_event
))) {
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
);
1384 spin_unlock_irq(&ctl
->read_lock
);
1386 return result
> 0 ? result
: err
;
1389 static unsigned int snd_ctl_poll(struct file
*file
, poll_table
* wait
)
1392 struct snd_ctl_file
*ctl
;
1394 ctl
= file
->private_data
;
1395 if (!ctl
->subscribed
)
1397 poll_wait(file
, &ctl
->change_sleep
, wait
);
1400 if (!list_empty(&ctl
->events
))
1401 mask
|= POLLIN
| POLLRDNORM
;
1407 * register the device-specific control-ioctls.
1408 * called from each device manager like pcm.c, hwdep.c, etc.
1410 static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn
, struct list_head
*lists
)
1412 struct snd_kctl_ioctl
*pn
;
1414 pn
= kzalloc(sizeof(struct snd_kctl_ioctl
), GFP_KERNEL
);
1418 down_write(&snd_ioctl_rwsem
);
1419 list_add_tail(&pn
->list
, lists
);
1420 up_write(&snd_ioctl_rwsem
);
1424 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn
)
1426 return _snd_ctl_register_ioctl(fcn
, &snd_control_ioctls
);
1429 EXPORT_SYMBOL(snd_ctl_register_ioctl
);
1431 #ifdef CONFIG_COMPAT
1432 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn
)
1434 return _snd_ctl_register_ioctl(fcn
, &snd_control_compat_ioctls
);
1437 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat
);
1441 * de-register the device-specific control-ioctls.
1443 static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn
,
1444 struct list_head
*lists
)
1446 struct snd_kctl_ioctl
*p
;
1448 if (snd_BUG_ON(!fcn
))
1450 down_write(&snd_ioctl_rwsem
);
1451 list_for_each_entry(p
, lists
, list
) {
1452 if (p
->fioctl
== fcn
) {
1454 up_write(&snd_ioctl_rwsem
);
1459 up_write(&snd_ioctl_rwsem
);
1464 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn
)
1466 return _snd_ctl_unregister_ioctl(fcn
, &snd_control_ioctls
);
1469 EXPORT_SYMBOL(snd_ctl_unregister_ioctl
);
1471 #ifdef CONFIG_COMPAT
1472 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn
)
1474 return _snd_ctl_unregister_ioctl(fcn
, &snd_control_compat_ioctls
);
1477 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat
);
1480 static int snd_ctl_fasync(int fd
, struct file
* file
, int on
)
1482 struct snd_ctl_file
*ctl
;
1484 ctl
= file
->private_data
;
1485 return fasync_helper(fd
, file
, on
, &ctl
->fasync
);
1491 #ifdef CONFIG_COMPAT
1492 #include "control_compat.c"
1494 #define snd_ctl_ioctl_compat NULL
1501 static const struct file_operations snd_ctl_f_ops
=
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
,
1515 * registration of the control device
1517 static int snd_ctl_dev_register(struct snd_device
*device
)
1519 struct snd_card
*card
= device
->device_data
;
1523 if (snd_BUG_ON(!card
))
1525 cardnum
= card
->number
;
1526 if (snd_BUG_ON(cardnum
< 0 || cardnum
>= SNDRV_CARDS
))
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)
1536 * disconnection of the control device
1538 static int snd_ctl_dev_disconnect(struct snd_device
*device
)
1540 struct snd_card
*card
= device
->device_data
;
1541 struct snd_ctl_file
*ctl
;
1544 if (snd_BUG_ON(!card
))
1546 cardnum
= card
->number
;
1547 if (snd_BUG_ON(cardnum
< 0 || cardnum
>= SNDRV_CARDS
))
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
);
1555 read_unlock(&card
->ctl_files_rwlock
);
1557 if ((err
= snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL
,
1566 static int snd_ctl_dev_free(struct snd_device
*device
)
1568 struct snd_card
*card
= device
->device_data
;
1569 struct snd_kcontrol
*control
;
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
);
1576 up_write(&card
->controls_rwsem
);
1581 * create control core:
1582 * called from init.c
1584 int snd_ctl_create(struct snd_card
*card
)
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
,
1592 if (snd_BUG_ON(!card
))
1594 return snd_device_new(card
, SNDRV_DEV_CONTROL
, card
, &ops
);
1598 * Frequently used control callbacks/helpers
1600 int snd_ctl_boolean_mono_info(struct snd_kcontrol
*kcontrol
,
1601 struct snd_ctl_elem_info
*uinfo
)
1603 uinfo
->type
= SNDRV_CTL_ELEM_TYPE_BOOLEAN
;
1605 uinfo
->value
.integer
.min
= 0;
1606 uinfo
->value
.integer
.max
= 1;
1610 EXPORT_SYMBOL(snd_ctl_boolean_mono_info
);
1612 int snd_ctl_boolean_stereo_info(struct snd_kcontrol
*kcontrol
,
1613 struct snd_ctl_elem_info
*uinfo
)
1615 uinfo
->type
= SNDRV_CTL_ELEM_TYPE_BOOLEAN
;
1617 uinfo
->value
.integer
.min
= 0;
1618 uinfo
->value
.integer
.max
= 1;
1622 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info
);
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
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.
1635 int snd_ctl_enum_info(struct snd_ctl_elem_info
*info
, unsigned int channels
,
1636 unsigned int items
, const char *const names
[])
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
));
1648 EXPORT_SYMBOL(snd_ctl_enum_info
);