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/module.h>
25 #include <linux/slab.h>
26 #include <linux/vmalloc.h>
27 #include <linux/time.h>
28 #include <sound/core.h>
29 #include <sound/minors.h>
30 #include <sound/info.h>
31 #include <sound/control.h>
33 /* max number of user-defined controls */
34 #define MAX_USER_CONTROLS 32
35 #define MAX_CONTROL_COUNT 1028
37 struct snd_kctl_ioctl
{
38 struct list_head list
; /* list of all ioctls */
39 snd_kctl_ioctl_func_t fioctl
;
42 static DECLARE_RWSEM(snd_ioctl_rwsem
);
43 static LIST_HEAD(snd_control_ioctls
);
45 static LIST_HEAD(snd_control_compat_ioctls
);
48 static int snd_ctl_open(struct inode
*inode
, struct file
*file
)
51 struct snd_card
*card
;
52 struct snd_ctl_file
*ctl
;
55 err
= nonseekable_open(inode
, file
);
59 card
= snd_lookup_minor_data(iminor(inode
), SNDRV_DEVICE_TYPE_CONTROL
);
64 err
= snd_card_file_add(card
, file
);
69 if (!try_module_get(card
->module
)) {
73 ctl
= kzalloc(sizeof(*ctl
), GFP_KERNEL
);
78 INIT_LIST_HEAD(&ctl
->events
);
79 init_waitqueue_head(&ctl
->change_sleep
);
80 spin_lock_init(&ctl
->read_lock
);
82 ctl
->prefer_pcm_subdevice
= -1;
83 ctl
->prefer_rawmidi_subdevice
= -1;
84 ctl
->pid
= get_pid(task_pid(current
));
85 file
->private_data
= ctl
;
86 write_lock_irqsave(&card
->ctl_files_rwlock
, flags
);
87 list_add_tail(&ctl
->list
, &card
->ctl_files
);
88 write_unlock_irqrestore(&card
->ctl_files_rwlock
, flags
);
93 module_put(card
->module
);
95 snd_card_file_remove(card
, file
);
102 static void snd_ctl_empty_read_queue(struct snd_ctl_file
* ctl
)
105 struct snd_kctl_event
*cread
;
107 spin_lock_irqsave(&ctl
->read_lock
, flags
);
108 while (!list_empty(&ctl
->events
)) {
109 cread
= snd_kctl_event(ctl
->events
.next
);
110 list_del(&cread
->list
);
113 spin_unlock_irqrestore(&ctl
->read_lock
, flags
);
116 static int snd_ctl_release(struct inode
*inode
, struct file
*file
)
119 struct snd_card
*card
;
120 struct snd_ctl_file
*ctl
;
121 struct snd_kcontrol
*control
;
124 ctl
= file
->private_data
;
125 file
->private_data
= NULL
;
127 write_lock_irqsave(&card
->ctl_files_rwlock
, flags
);
128 list_del(&ctl
->list
);
129 write_unlock_irqrestore(&card
->ctl_files_rwlock
, flags
);
130 down_write(&card
->controls_rwsem
);
131 list_for_each_entry(control
, &card
->controls
, list
)
132 for (idx
= 0; idx
< control
->count
; idx
++)
133 if (control
->vd
[idx
].owner
== ctl
)
134 control
->vd
[idx
].owner
= NULL
;
135 up_write(&card
->controls_rwsem
);
136 snd_ctl_empty_read_queue(ctl
);
139 module_put(card
->module
);
140 snd_card_file_remove(card
, file
);
144 void snd_ctl_notify(struct snd_card
*card
, unsigned int mask
,
145 struct snd_ctl_elem_id
*id
)
148 struct snd_ctl_file
*ctl
;
149 struct snd_kctl_event
*ev
;
151 if (snd_BUG_ON(!card
|| !id
))
153 read_lock(&card
->ctl_files_rwlock
);
154 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
155 card
->mixer_oss_change_count
++;
157 list_for_each_entry(ctl
, &card
->ctl_files
, list
) {
158 if (!ctl
->subscribed
)
160 spin_lock_irqsave(&ctl
->read_lock
, flags
);
161 list_for_each_entry(ev
, &ctl
->events
, list
) {
162 if (ev
->id
.numid
== id
->numid
) {
167 ev
= kzalloc(sizeof(*ev
), GFP_ATOMIC
);
171 list_add_tail(&ev
->list
, &ctl
->events
);
173 dev_err(card
->dev
, "No memory available to allocate event\n");
176 wake_up(&ctl
->change_sleep
);
177 spin_unlock_irqrestore(&ctl
->read_lock
, flags
);
178 kill_fasync(&ctl
->fasync
, SIGIO
, POLL_IN
);
180 read_unlock(&card
->ctl_files_rwlock
);
183 EXPORT_SYMBOL(snd_ctl_notify
);
186 * snd_ctl_new - create a control instance from the template
187 * @control: the control template
188 * @access: the default control access
190 * Allocates a new struct snd_kcontrol instance and copies the given template
191 * to the new instance. It does not copy volatile data (access).
193 * Return: The pointer of the new instance, or %NULL on failure.
195 static struct snd_kcontrol
*snd_ctl_new(struct snd_kcontrol
*control
,
198 struct snd_kcontrol
*kctl
;
201 if (snd_BUG_ON(!control
|| !control
->count
))
204 if (control
->count
> MAX_CONTROL_COUNT
)
207 kctl
= kzalloc(sizeof(*kctl
) + sizeof(struct snd_kcontrol_volatile
) * control
->count
, GFP_KERNEL
);
209 pr_err("ALSA: Cannot allocate control instance\n");
213 for (idx
= 0; idx
< kctl
->count
; idx
++)
214 kctl
->vd
[idx
].access
= access
;
219 * snd_ctl_new1 - create a control instance from the template
220 * @ncontrol: the initialization record
221 * @private_data: the private data to set
223 * Allocates a new struct snd_kcontrol instance and initialize from the given
224 * template. When the access field of ncontrol is 0, it's assumed as
225 * READWRITE access. When the count field is 0, it's assumes as one.
227 * Return: The pointer of the newly generated instance, or %NULL on failure.
229 struct snd_kcontrol
*snd_ctl_new1(const struct snd_kcontrol_new
*ncontrol
,
232 struct snd_kcontrol kctl
;
235 if (snd_BUG_ON(!ncontrol
|| !ncontrol
->info
))
237 memset(&kctl
, 0, sizeof(kctl
));
238 kctl
.id
.iface
= ncontrol
->iface
;
239 kctl
.id
.device
= ncontrol
->device
;
240 kctl
.id
.subdevice
= ncontrol
->subdevice
;
241 if (ncontrol
->name
) {
242 strlcpy(kctl
.id
.name
, ncontrol
->name
, sizeof(kctl
.id
.name
));
243 if (strcmp(ncontrol
->name
, kctl
.id
.name
) != 0)
244 pr_warn("ALSA: Control name '%s' truncated to '%s'\n",
245 ncontrol
->name
, kctl
.id
.name
);
247 kctl
.id
.index
= ncontrol
->index
;
248 kctl
.count
= ncontrol
->count
? ncontrol
->count
: 1;
249 access
= ncontrol
->access
== 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE
:
250 (ncontrol
->access
& (SNDRV_CTL_ELEM_ACCESS_READWRITE
|
251 SNDRV_CTL_ELEM_ACCESS_VOLATILE
|
252 SNDRV_CTL_ELEM_ACCESS_INACTIVE
|
253 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE
|
254 SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND
|
255 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK
));
256 kctl
.info
= ncontrol
->info
;
257 kctl
.get
= ncontrol
->get
;
258 kctl
.put
= ncontrol
->put
;
259 kctl
.tlv
.p
= ncontrol
->tlv
.p
;
260 kctl
.private_value
= ncontrol
->private_value
;
261 kctl
.private_data
= private_data
;
262 return snd_ctl_new(&kctl
, access
);
265 EXPORT_SYMBOL(snd_ctl_new1
);
268 * snd_ctl_free_one - release the control instance
269 * @kcontrol: the control instance
271 * Releases the control instance created via snd_ctl_new()
273 * Don't call this after the control was added to the card.
275 void snd_ctl_free_one(struct snd_kcontrol
*kcontrol
)
278 if (kcontrol
->private_free
)
279 kcontrol
->private_free(kcontrol
);
284 EXPORT_SYMBOL(snd_ctl_free_one
);
286 static bool snd_ctl_remove_numid_conflict(struct snd_card
*card
,
289 struct snd_kcontrol
*kctl
;
291 list_for_each_entry(kctl
, &card
->controls
, list
) {
292 if (kctl
->id
.numid
< card
->last_numid
+ 1 + count
&&
293 kctl
->id
.numid
+ kctl
->count
> card
->last_numid
+ 1) {
294 card
->last_numid
= kctl
->id
.numid
+ kctl
->count
- 1;
301 static int snd_ctl_find_hole(struct snd_card
*card
, unsigned int count
)
303 unsigned int iter
= 100000;
305 while (snd_ctl_remove_numid_conflict(card
, count
)) {
307 /* this situation is very unlikely */
308 dev_err(card
->dev
, "unable to allocate new control numid\n");
316 * snd_ctl_add - add the control instance to the card
317 * @card: the card instance
318 * @kcontrol: the control instance to add
320 * Adds the control instance created via snd_ctl_new() or
321 * snd_ctl_new1() to the given card. Assigns also an unique
322 * numid used for fast search.
324 * It frees automatically the control which cannot be added.
326 * Return: Zero if successful, or a negative error code on failure.
329 int snd_ctl_add(struct snd_card
*card
, struct snd_kcontrol
*kcontrol
)
331 struct snd_ctl_elem_id id
;
337 if (snd_BUG_ON(!card
|| !kcontrol
->info
))
340 down_write(&card
->controls_rwsem
);
341 if (snd_ctl_find_id(card
, &id
)) {
342 up_write(&card
->controls_rwsem
);
343 dev_err(card
->dev
, "control %i:%i:%i:%s:%i is already present\n",
352 if (snd_ctl_find_hole(card
, kcontrol
->count
) < 0) {
353 up_write(&card
->controls_rwsem
);
357 list_add_tail(&kcontrol
->list
, &card
->controls
);
358 card
->controls_count
+= kcontrol
->count
;
359 kcontrol
->id
.numid
= card
->last_numid
+ 1;
360 card
->last_numid
+= kcontrol
->count
;
361 up_write(&card
->controls_rwsem
);
362 for (idx
= 0; idx
< kcontrol
->count
; idx
++, id
.index
++, id
.numid
++)
363 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_ADD
, &id
);
367 snd_ctl_free_one(kcontrol
);
371 EXPORT_SYMBOL(snd_ctl_add
);
374 * snd_ctl_replace - replace the control instance of the card
375 * @card: the card instance
376 * @kcontrol: the control instance to replace
377 * @add_on_replace: add the control if not already added
379 * Replaces the given control. If the given control does not exist
380 * and the add_on_replace flag is set, the control is added. If the
381 * control exists, it is destroyed first.
383 * It frees automatically the control which cannot be added or replaced.
385 * Return: Zero if successful, or a negative error code on failure.
387 int snd_ctl_replace(struct snd_card
*card
, struct snd_kcontrol
*kcontrol
,
390 struct snd_ctl_elem_id id
;
392 struct snd_kcontrol
*old
;
397 if (snd_BUG_ON(!card
|| !kcontrol
->info
)) {
402 down_write(&card
->controls_rwsem
);
403 old
= snd_ctl_find_id(card
, &id
);
407 up_write(&card
->controls_rwsem
);
411 ret
= snd_ctl_remove(card
, old
);
413 up_write(&card
->controls_rwsem
);
417 if (snd_ctl_find_hole(card
, kcontrol
->count
) < 0) {
418 up_write(&card
->controls_rwsem
);
422 list_add_tail(&kcontrol
->list
, &card
->controls
);
423 card
->controls_count
+= kcontrol
->count
;
424 kcontrol
->id
.numid
= card
->last_numid
+ 1;
425 card
->last_numid
+= kcontrol
->count
;
426 up_write(&card
->controls_rwsem
);
427 for (idx
= 0; idx
< kcontrol
->count
; idx
++, id
.index
++, id
.numid
++)
428 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_ADD
, &id
);
432 snd_ctl_free_one(kcontrol
);
435 EXPORT_SYMBOL(snd_ctl_replace
);
438 * snd_ctl_remove - remove the control from the card and release it
439 * @card: the card instance
440 * @kcontrol: the control instance to remove
442 * Removes the control from the card and then releases the instance.
443 * You don't need to call snd_ctl_free_one(). You must be in
444 * the write lock - down_write(&card->controls_rwsem).
446 * Return: 0 if successful, or a negative error code on failure.
448 int snd_ctl_remove(struct snd_card
*card
, struct snd_kcontrol
*kcontrol
)
450 struct snd_ctl_elem_id id
;
453 if (snd_BUG_ON(!card
|| !kcontrol
))
455 list_del(&kcontrol
->list
);
456 card
->controls_count
-= kcontrol
->count
;
458 for (idx
= 0; idx
< kcontrol
->count
; idx
++, id
.index
++, id
.numid
++)
459 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_REMOVE
, &id
);
460 snd_ctl_free_one(kcontrol
);
464 EXPORT_SYMBOL(snd_ctl_remove
);
467 * snd_ctl_remove_id - remove the control of the given id and release it
468 * @card: the card instance
469 * @id: the control id to remove
471 * Finds the control instance with the given id, removes it from the
472 * card list and releases it.
474 * Return: 0 if successful, or a negative error code on failure.
476 int snd_ctl_remove_id(struct snd_card
*card
, struct snd_ctl_elem_id
*id
)
478 struct snd_kcontrol
*kctl
;
481 down_write(&card
->controls_rwsem
);
482 kctl
= snd_ctl_find_id(card
, id
);
484 up_write(&card
->controls_rwsem
);
487 ret
= snd_ctl_remove(card
, kctl
);
488 up_write(&card
->controls_rwsem
);
492 EXPORT_SYMBOL(snd_ctl_remove_id
);
495 * snd_ctl_remove_user_ctl - remove and release the unlocked user control
496 * @file: active control handle
497 * @id: the control id to remove
499 * Finds the control instance with the given id, removes it from the
500 * card list and releases it.
502 * Return: 0 if successful, or a negative error code on failure.
504 static int snd_ctl_remove_user_ctl(struct snd_ctl_file
* file
,
505 struct snd_ctl_elem_id
*id
)
507 struct snd_card
*card
= file
->card
;
508 struct snd_kcontrol
*kctl
;
511 down_write(&card
->controls_rwsem
);
512 kctl
= snd_ctl_find_id(card
, id
);
517 if (!(kctl
->vd
[0].access
& SNDRV_CTL_ELEM_ACCESS_USER
)) {
521 for (idx
= 0; idx
< kctl
->count
; idx
++)
522 if (kctl
->vd
[idx
].owner
!= NULL
&& kctl
->vd
[idx
].owner
!= file
) {
526 ret
= snd_ctl_remove(card
, kctl
);
529 card
->user_ctl_count
--;
531 up_write(&card
->controls_rwsem
);
536 * snd_ctl_activate_id - activate/inactivate the control of the given id
537 * @card: the card instance
538 * @id: the control id to activate/inactivate
539 * @active: non-zero to activate
541 * Finds the control instance with the given id, and activate or
542 * inactivate the control together with notification, if changed.
544 * Return: 0 if unchanged, 1 if changed, or a negative error code on failure.
546 int snd_ctl_activate_id(struct snd_card
*card
, struct snd_ctl_elem_id
*id
,
549 struct snd_kcontrol
*kctl
;
550 struct snd_kcontrol_volatile
*vd
;
551 unsigned int index_offset
;
554 down_write(&card
->controls_rwsem
);
555 kctl
= snd_ctl_find_id(card
, id
);
560 index_offset
= snd_ctl_get_ioff(kctl
, &kctl
->id
);
561 vd
= &kctl
->vd
[index_offset
];
564 if (!(vd
->access
& SNDRV_CTL_ELEM_ACCESS_INACTIVE
))
566 vd
->access
&= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE
;
568 if (vd
->access
& SNDRV_CTL_ELEM_ACCESS_INACTIVE
)
570 vd
->access
|= SNDRV_CTL_ELEM_ACCESS_INACTIVE
;
574 up_write(&card
->controls_rwsem
);
576 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_INFO
, id
);
579 EXPORT_SYMBOL_GPL(snd_ctl_activate_id
);
582 * snd_ctl_rename_id - replace the id of a control on the card
583 * @card: the card instance
584 * @src_id: the old id
585 * @dst_id: the new id
587 * Finds the control with the old id from the card, and replaces the
588 * id with the new one.
590 * Return: Zero if successful, or a negative error code on failure.
592 int snd_ctl_rename_id(struct snd_card
*card
, struct snd_ctl_elem_id
*src_id
,
593 struct snd_ctl_elem_id
*dst_id
)
595 struct snd_kcontrol
*kctl
;
597 down_write(&card
->controls_rwsem
);
598 kctl
= snd_ctl_find_id(card
, src_id
);
600 up_write(&card
->controls_rwsem
);
604 kctl
->id
.numid
= card
->last_numid
+ 1;
605 card
->last_numid
+= kctl
->count
;
606 up_write(&card
->controls_rwsem
);
610 EXPORT_SYMBOL(snd_ctl_rename_id
);
613 * snd_ctl_find_numid - find the control instance with the given number-id
614 * @card: the card instance
615 * @numid: the number-id to search
617 * Finds the control instance with the given number-id from the card.
619 * The caller must down card->controls_rwsem before calling this function
620 * (if the race condition can happen).
622 * Return: The pointer of the instance if found, or %NULL if not.
625 struct snd_kcontrol
*snd_ctl_find_numid(struct snd_card
*card
, unsigned int numid
)
627 struct snd_kcontrol
*kctl
;
629 if (snd_BUG_ON(!card
|| !numid
))
631 list_for_each_entry(kctl
, &card
->controls
, list
) {
632 if (kctl
->id
.numid
<= numid
&& kctl
->id
.numid
+ kctl
->count
> numid
)
638 EXPORT_SYMBOL(snd_ctl_find_numid
);
641 * snd_ctl_find_id - find the control instance with the given id
642 * @card: the card instance
643 * @id: the id to search
645 * Finds the control instance with the given id from the card.
647 * The caller must down card->controls_rwsem before calling this function
648 * (if the race condition can happen).
650 * Return: The pointer of the instance if found, or %NULL if not.
653 struct snd_kcontrol
*snd_ctl_find_id(struct snd_card
*card
,
654 struct snd_ctl_elem_id
*id
)
656 struct snd_kcontrol
*kctl
;
658 if (snd_BUG_ON(!card
|| !id
))
661 return snd_ctl_find_numid(card
, id
->numid
);
662 list_for_each_entry(kctl
, &card
->controls
, list
) {
663 if (kctl
->id
.iface
!= id
->iface
)
665 if (kctl
->id
.device
!= id
->device
)
667 if (kctl
->id
.subdevice
!= id
->subdevice
)
669 if (strncmp(kctl
->id
.name
, id
->name
, sizeof(kctl
->id
.name
)))
671 if (kctl
->id
.index
> id
->index
)
673 if (kctl
->id
.index
+ kctl
->count
<= id
->index
)
680 EXPORT_SYMBOL(snd_ctl_find_id
);
682 static int snd_ctl_card_info(struct snd_card
*card
, struct snd_ctl_file
* ctl
,
683 unsigned int cmd
, void __user
*arg
)
685 struct snd_ctl_card_info
*info
;
687 info
= kzalloc(sizeof(*info
), GFP_KERNEL
);
690 down_read(&snd_ioctl_rwsem
);
691 info
->card
= card
->number
;
692 strlcpy(info
->id
, card
->id
, sizeof(info
->id
));
693 strlcpy(info
->driver
, card
->driver
, sizeof(info
->driver
));
694 strlcpy(info
->name
, card
->shortname
, sizeof(info
->name
));
695 strlcpy(info
->longname
, card
->longname
, sizeof(info
->longname
));
696 strlcpy(info
->mixername
, card
->mixername
, sizeof(info
->mixername
));
697 strlcpy(info
->components
, card
->components
, sizeof(info
->components
));
698 up_read(&snd_ioctl_rwsem
);
699 if (copy_to_user(arg
, info
, sizeof(struct snd_ctl_card_info
))) {
707 static int snd_ctl_elem_list(struct snd_card
*card
,
708 struct snd_ctl_elem_list __user
*_list
)
710 struct list_head
*plist
;
711 struct snd_ctl_elem_list list
;
712 struct snd_kcontrol
*kctl
;
713 struct snd_ctl_elem_id
*dst
, *id
;
714 unsigned int offset
, space
, jidx
;
716 if (copy_from_user(&list
, _list
, sizeof(list
)))
718 offset
= list
.offset
;
720 /* try limit maximum space */
724 /* allocate temporary buffer for atomic operation */
725 dst
= vmalloc(space
* sizeof(struct snd_ctl_elem_id
));
728 down_read(&card
->controls_rwsem
);
729 list
.count
= card
->controls_count
;
730 plist
= card
->controls
.next
;
731 while (plist
!= &card
->controls
) {
734 kctl
= snd_kcontrol(plist
);
735 if (offset
< kctl
->count
)
737 offset
-= kctl
->count
;
742 while (space
> 0 && plist
!= &card
->controls
) {
743 kctl
= snd_kcontrol(plist
);
744 for (jidx
= offset
; space
> 0 && jidx
< kctl
->count
; jidx
++) {
745 snd_ctl_build_ioff(id
, kctl
, jidx
);
753 up_read(&card
->controls_rwsem
);
755 copy_to_user(list
.pids
, dst
,
756 list
.used
* sizeof(struct snd_ctl_elem_id
))) {
762 down_read(&card
->controls_rwsem
);
763 list
.count
= card
->controls_count
;
764 up_read(&card
->controls_rwsem
);
766 if (copy_to_user(_list
, &list
, sizeof(list
)))
771 static int snd_ctl_elem_info(struct snd_ctl_file
*ctl
,
772 struct snd_ctl_elem_info
*info
)
774 struct snd_card
*card
= ctl
->card
;
775 struct snd_kcontrol
*kctl
;
776 struct snd_kcontrol_volatile
*vd
;
777 unsigned int index_offset
;
780 down_read(&card
->controls_rwsem
);
781 kctl
= snd_ctl_find_id(card
, &info
->id
);
783 up_read(&card
->controls_rwsem
);
786 #ifdef CONFIG_SND_DEBUG
789 result
= kctl
->info(kctl
, info
);
791 snd_BUG_ON(info
->access
);
792 index_offset
= snd_ctl_get_ioff(kctl
, &info
->id
);
793 vd
= &kctl
->vd
[index_offset
];
794 snd_ctl_build_ioff(&info
->id
, kctl
, index_offset
);
795 info
->access
= vd
->access
;
797 info
->access
|= SNDRV_CTL_ELEM_ACCESS_LOCK
;
798 if (vd
->owner
== ctl
)
799 info
->access
|= SNDRV_CTL_ELEM_ACCESS_OWNER
;
800 info
->owner
= pid_vnr(vd
->owner
->pid
);
805 up_read(&card
->controls_rwsem
);
809 static int snd_ctl_elem_info_user(struct snd_ctl_file
*ctl
,
810 struct snd_ctl_elem_info __user
*_info
)
812 struct snd_ctl_elem_info info
;
815 if (copy_from_user(&info
, _info
, sizeof(info
)))
817 snd_power_lock(ctl
->card
);
818 result
= snd_power_wait(ctl
->card
, SNDRV_CTL_POWER_D0
);
820 result
= snd_ctl_elem_info(ctl
, &info
);
821 snd_power_unlock(ctl
->card
);
823 if (copy_to_user(_info
, &info
, sizeof(info
)))
828 static int snd_ctl_elem_read(struct snd_card
*card
,
829 struct snd_ctl_elem_value
*control
)
831 struct snd_kcontrol
*kctl
;
832 struct snd_kcontrol_volatile
*vd
;
833 unsigned int index_offset
;
836 down_read(&card
->controls_rwsem
);
837 kctl
= snd_ctl_find_id(card
, &control
->id
);
841 index_offset
= snd_ctl_get_ioff(kctl
, &control
->id
);
842 vd
= &kctl
->vd
[index_offset
];
843 if ((vd
->access
& SNDRV_CTL_ELEM_ACCESS_READ
) &&
845 snd_ctl_build_ioff(&control
->id
, kctl
, index_offset
);
846 result
= kctl
->get(kctl
, control
);
850 up_read(&card
->controls_rwsem
);
854 static int snd_ctl_elem_read_user(struct snd_card
*card
,
855 struct snd_ctl_elem_value __user
*_control
)
857 struct snd_ctl_elem_value
*control
;
860 control
= memdup_user(_control
, sizeof(*control
));
862 return PTR_ERR(control
);
864 snd_power_lock(card
);
865 result
= snd_power_wait(card
, SNDRV_CTL_POWER_D0
);
867 result
= snd_ctl_elem_read(card
, control
);
868 snd_power_unlock(card
);
870 if (copy_to_user(_control
, control
, sizeof(*control
)))
876 static int snd_ctl_elem_write(struct snd_card
*card
, struct snd_ctl_file
*file
,
877 struct snd_ctl_elem_value
*control
)
879 struct snd_kcontrol
*kctl
;
880 struct snd_kcontrol_volatile
*vd
;
881 unsigned int index_offset
;
884 down_read(&card
->controls_rwsem
);
885 kctl
= snd_ctl_find_id(card
, &control
->id
);
889 index_offset
= snd_ctl_get_ioff(kctl
, &control
->id
);
890 vd
= &kctl
->vd
[index_offset
];
891 if (!(vd
->access
& SNDRV_CTL_ELEM_ACCESS_WRITE
) ||
893 (file
&& vd
->owner
&& vd
->owner
!= file
)) {
896 snd_ctl_build_ioff(&control
->id
, kctl
, index_offset
);
897 result
= kctl
->put(kctl
, control
);
900 up_read(&card
->controls_rwsem
);
901 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_VALUE
,
906 up_read(&card
->controls_rwsem
);
910 static int snd_ctl_elem_write_user(struct snd_ctl_file
*file
,
911 struct snd_ctl_elem_value __user
*_control
)
913 struct snd_ctl_elem_value
*control
;
914 struct snd_card
*card
;
917 control
= memdup_user(_control
, sizeof(*control
));
919 return PTR_ERR(control
);
922 snd_power_lock(card
);
923 result
= snd_power_wait(card
, SNDRV_CTL_POWER_D0
);
925 result
= snd_ctl_elem_write(card
, file
, control
);
926 snd_power_unlock(card
);
928 if (copy_to_user(_control
, control
, sizeof(*control
)))
934 static int snd_ctl_elem_lock(struct snd_ctl_file
*file
,
935 struct snd_ctl_elem_id __user
*_id
)
937 struct snd_card
*card
= file
->card
;
938 struct snd_ctl_elem_id id
;
939 struct snd_kcontrol
*kctl
;
940 struct snd_kcontrol_volatile
*vd
;
943 if (copy_from_user(&id
, _id
, sizeof(id
)))
945 down_write(&card
->controls_rwsem
);
946 kctl
= snd_ctl_find_id(card
, &id
);
950 vd
= &kctl
->vd
[snd_ctl_get_ioff(kctl
, &id
)];
951 if (vd
->owner
!= NULL
)
958 up_write(&card
->controls_rwsem
);
962 static int snd_ctl_elem_unlock(struct snd_ctl_file
*file
,
963 struct snd_ctl_elem_id __user
*_id
)
965 struct snd_card
*card
= file
->card
;
966 struct snd_ctl_elem_id id
;
967 struct snd_kcontrol
*kctl
;
968 struct snd_kcontrol_volatile
*vd
;
971 if (copy_from_user(&id
, _id
, sizeof(id
)))
973 down_write(&card
->controls_rwsem
);
974 kctl
= snd_ctl_find_id(card
, &id
);
978 vd
= &kctl
->vd
[snd_ctl_get_ioff(kctl
, &id
)];
979 if (vd
->owner
== NULL
)
981 else if (vd
->owner
!= file
)
988 up_write(&card
->controls_rwsem
);
992 struct user_element
{
993 struct snd_ctl_elem_info info
;
994 struct snd_card
*card
;
995 void *elem_data
; /* element data */
996 unsigned long elem_data_size
; /* size of element data in bytes */
997 void *tlv_data
; /* TLV data */
998 unsigned long tlv_data_size
; /* TLV data size */
999 void *priv_data
; /* private data (like strings for enumerated type) */
1002 static int snd_ctl_elem_user_info(struct snd_kcontrol
*kcontrol
,
1003 struct snd_ctl_elem_info
*uinfo
)
1005 struct user_element
*ue
= kcontrol
->private_data
;
1011 static int snd_ctl_elem_user_enum_info(struct snd_kcontrol
*kcontrol
,
1012 struct snd_ctl_elem_info
*uinfo
)
1014 struct user_element
*ue
= kcontrol
->private_data
;
1018 item
= uinfo
->value
.enumerated
.item
;
1022 item
= min(item
, uinfo
->value
.enumerated
.items
- 1);
1023 uinfo
->value
.enumerated
.item
= item
;
1025 names
= ue
->priv_data
;
1026 for (; item
> 0; --item
)
1027 names
+= strlen(names
) + 1;
1028 strcpy(uinfo
->value
.enumerated
.name
, names
);
1033 static int snd_ctl_elem_user_get(struct snd_kcontrol
*kcontrol
,
1034 struct snd_ctl_elem_value
*ucontrol
)
1036 struct user_element
*ue
= kcontrol
->private_data
;
1038 mutex_lock(&ue
->card
->user_ctl_lock
);
1039 memcpy(&ucontrol
->value
, ue
->elem_data
, ue
->elem_data_size
);
1040 mutex_unlock(&ue
->card
->user_ctl_lock
);
1044 static int snd_ctl_elem_user_put(struct snd_kcontrol
*kcontrol
,
1045 struct snd_ctl_elem_value
*ucontrol
)
1048 struct user_element
*ue
= kcontrol
->private_data
;
1050 mutex_lock(&ue
->card
->user_ctl_lock
);
1051 change
= memcmp(&ucontrol
->value
, ue
->elem_data
, ue
->elem_data_size
) != 0;
1053 memcpy(ue
->elem_data
, &ucontrol
->value
, ue
->elem_data_size
);
1054 mutex_unlock(&ue
->card
->user_ctl_lock
);
1058 static int snd_ctl_elem_user_tlv(struct snd_kcontrol
*kcontrol
,
1061 unsigned int __user
*tlv
)
1063 struct user_element
*ue
= kcontrol
->private_data
;
1068 if (size
> 1024 * 128) /* sane value */
1071 new_data
= memdup_user(tlv
, size
);
1072 if (IS_ERR(new_data
))
1073 return PTR_ERR(new_data
);
1074 mutex_lock(&ue
->card
->user_ctl_lock
);
1075 change
= ue
->tlv_data_size
!= size
;
1077 change
= memcmp(ue
->tlv_data
, new_data
, size
);
1078 kfree(ue
->tlv_data
);
1079 ue
->tlv_data
= new_data
;
1080 ue
->tlv_data_size
= size
;
1081 mutex_unlock(&ue
->card
->user_ctl_lock
);
1085 mutex_lock(&ue
->card
->user_ctl_lock
);
1086 if (!ue
->tlv_data_size
|| !ue
->tlv_data
) {
1090 if (size
< ue
->tlv_data_size
) {
1094 if (copy_to_user(tlv
, ue
->tlv_data
, ue
->tlv_data_size
))
1097 mutex_unlock(&ue
->card
->user_ctl_lock
);
1104 static int snd_ctl_elem_init_enum_names(struct user_element
*ue
)
1107 size_t buf_len
, name_len
;
1109 const uintptr_t user_ptrval
= ue
->info
.value
.enumerated
.names_ptr
;
1111 if (ue
->info
.value
.enumerated
.names_length
> 64 * 1024)
1114 names
= memdup_user((const void __user
*)user_ptrval
,
1115 ue
->info
.value
.enumerated
.names_length
);
1117 return PTR_ERR(names
);
1119 /* check that there are enough valid names */
1120 buf_len
= ue
->info
.value
.enumerated
.names_length
;
1122 for (i
= 0; i
< ue
->info
.value
.enumerated
.items
; ++i
) {
1123 name_len
= strnlen(p
, buf_len
);
1124 if (name_len
== 0 || name_len
>= 64 || name_len
== buf_len
) {
1129 buf_len
-= name_len
+ 1;
1132 ue
->priv_data
= names
;
1133 ue
->info
.value
.enumerated
.names_ptr
= 0;
1138 static void snd_ctl_elem_user_free(struct snd_kcontrol
*kcontrol
)
1140 struct user_element
*ue
= kcontrol
->private_data
;
1142 kfree(ue
->tlv_data
);
1143 kfree(ue
->priv_data
);
1147 static int snd_ctl_elem_add(struct snd_ctl_file
*file
,
1148 struct snd_ctl_elem_info
*info
, int replace
)
1150 struct snd_card
*card
= file
->card
;
1151 struct snd_kcontrol kctl
, *_kctl
;
1152 unsigned int access
;
1154 struct user_element
*ue
;
1157 if (!replace
&& card
->user_ctl_count
>= MAX_USER_CONTROLS
)
1159 if (info
->count
< 1)
1161 access
= info
->access
== 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE
:
1162 (info
->access
& (SNDRV_CTL_ELEM_ACCESS_READWRITE
|
1163 SNDRV_CTL_ELEM_ACCESS_INACTIVE
|
1164 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE
));
1166 memset(&kctl
, 0, sizeof(kctl
));
1167 down_write(&card
->controls_rwsem
);
1168 _kctl
= snd_ctl_find_id(card
, &info
->id
);
1172 err
= snd_ctl_remove(card
, _kctl
);
1179 up_write(&card
->controls_rwsem
);
1182 memcpy(&kctl
.id
, &info
->id
, sizeof(info
->id
));
1183 kctl
.count
= info
->owner
? info
->owner
: 1;
1184 access
|= SNDRV_CTL_ELEM_ACCESS_USER
;
1185 if (info
->type
== SNDRV_CTL_ELEM_TYPE_ENUMERATED
)
1186 kctl
.info
= snd_ctl_elem_user_enum_info
;
1188 kctl
.info
= snd_ctl_elem_user_info
;
1189 if (access
& SNDRV_CTL_ELEM_ACCESS_READ
)
1190 kctl
.get
= snd_ctl_elem_user_get
;
1191 if (access
& SNDRV_CTL_ELEM_ACCESS_WRITE
)
1192 kctl
.put
= snd_ctl_elem_user_put
;
1193 if (access
& SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE
) {
1194 kctl
.tlv
.c
= snd_ctl_elem_user_tlv
;
1195 access
|= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK
;
1197 switch (info
->type
) {
1198 case SNDRV_CTL_ELEM_TYPE_BOOLEAN
:
1199 case SNDRV_CTL_ELEM_TYPE_INTEGER
:
1200 private_size
= sizeof(long);
1201 if (info
->count
> 128)
1204 case SNDRV_CTL_ELEM_TYPE_INTEGER64
:
1205 private_size
= sizeof(long long);
1206 if (info
->count
> 64)
1209 case SNDRV_CTL_ELEM_TYPE_ENUMERATED
:
1210 private_size
= sizeof(unsigned int);
1211 if (info
->count
> 128 || info
->value
.enumerated
.items
== 0)
1214 case SNDRV_CTL_ELEM_TYPE_BYTES
:
1215 private_size
= sizeof(unsigned char);
1216 if (info
->count
> 512)
1219 case SNDRV_CTL_ELEM_TYPE_IEC958
:
1220 private_size
= sizeof(struct snd_aes_iec958
);
1221 if (info
->count
!= 1)
1227 private_size
*= info
->count
;
1228 ue
= kzalloc(sizeof(struct user_element
) + private_size
, GFP_KERNEL
);
1233 ue
->info
.access
= 0;
1234 ue
->elem_data
= (char *)ue
+ sizeof(*ue
);
1235 ue
->elem_data_size
= private_size
;
1236 if (ue
->info
.type
== SNDRV_CTL_ELEM_TYPE_ENUMERATED
) {
1237 err
= snd_ctl_elem_init_enum_names(ue
);
1243 kctl
.private_free
= snd_ctl_elem_user_free
;
1244 _kctl
= snd_ctl_new(&kctl
, access
);
1245 if (_kctl
== NULL
) {
1246 kfree(ue
->priv_data
);
1250 _kctl
->private_data
= ue
;
1251 for (idx
= 0; idx
< _kctl
->count
; idx
++)
1252 _kctl
->vd
[idx
].owner
= file
;
1253 err
= snd_ctl_add(card
, _kctl
);
1257 down_write(&card
->controls_rwsem
);
1258 card
->user_ctl_count
++;
1259 up_write(&card
->controls_rwsem
);
1264 static int snd_ctl_elem_add_user(struct snd_ctl_file
*file
,
1265 struct snd_ctl_elem_info __user
*_info
, int replace
)
1267 struct snd_ctl_elem_info info
;
1268 if (copy_from_user(&info
, _info
, sizeof(info
)))
1270 return snd_ctl_elem_add(file
, &info
, replace
);
1273 static int snd_ctl_elem_remove(struct snd_ctl_file
*file
,
1274 struct snd_ctl_elem_id __user
*_id
)
1276 struct snd_ctl_elem_id id
;
1278 if (copy_from_user(&id
, _id
, sizeof(id
)))
1280 return snd_ctl_remove_user_ctl(file
, &id
);
1283 static int snd_ctl_subscribe_events(struct snd_ctl_file
*file
, int __user
*ptr
)
1286 if (get_user(subscribe
, ptr
))
1288 if (subscribe
< 0) {
1289 subscribe
= file
->subscribed
;
1290 if (put_user(subscribe
, ptr
))
1295 file
->subscribed
= 1;
1297 } else if (file
->subscribed
) {
1298 snd_ctl_empty_read_queue(file
);
1299 file
->subscribed
= 0;
1304 static int snd_ctl_tlv_ioctl(struct snd_ctl_file
*file
,
1305 struct snd_ctl_tlv __user
*_tlv
,
1308 struct snd_card
*card
= file
->card
;
1309 struct snd_ctl_tlv tlv
;
1310 struct snd_kcontrol
*kctl
;
1311 struct snd_kcontrol_volatile
*vd
;
1315 if (copy_from_user(&tlv
, _tlv
, sizeof(tlv
)))
1317 if (tlv
.length
< sizeof(unsigned int) * 2)
1319 down_read(&card
->controls_rwsem
);
1320 kctl
= snd_ctl_find_numid(card
, tlv
.numid
);
1325 if (kctl
->tlv
.p
== NULL
) {
1329 vd
= &kctl
->vd
[tlv
.numid
- kctl
->id
.numid
];
1330 if ((op_flag
== 0 && (vd
->access
& SNDRV_CTL_ELEM_ACCESS_TLV_READ
) == 0) ||
1331 (op_flag
> 0 && (vd
->access
& SNDRV_CTL_ELEM_ACCESS_TLV_WRITE
) == 0) ||
1332 (op_flag
< 0 && (vd
->access
& SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND
) == 0)) {
1336 if (vd
->access
& SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK
) {
1337 if (vd
->owner
!= NULL
&& vd
->owner
!= file
) {
1341 err
= kctl
->tlv
.c(kctl
, op_flag
, tlv
.length
, _tlv
->tlv
);
1343 up_read(&card
->controls_rwsem
);
1344 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_TLV
, &kctl
->id
);
1352 len
= kctl
->tlv
.p
[1] + 2 * sizeof(unsigned int);
1353 if (tlv
.length
< len
) {
1357 if (copy_to_user(_tlv
->tlv
, kctl
->tlv
.p
, len
))
1361 up_read(&card
->controls_rwsem
);
1365 static long snd_ctl_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1367 struct snd_ctl_file
*ctl
;
1368 struct snd_card
*card
;
1369 struct snd_kctl_ioctl
*p
;
1370 void __user
*argp
= (void __user
*)arg
;
1371 int __user
*ip
= argp
;
1374 ctl
= file
->private_data
;
1376 if (snd_BUG_ON(!card
))
1379 case SNDRV_CTL_IOCTL_PVERSION
:
1380 return put_user(SNDRV_CTL_VERSION
, ip
) ? -EFAULT
: 0;
1381 case SNDRV_CTL_IOCTL_CARD_INFO
:
1382 return snd_ctl_card_info(card
, ctl
, cmd
, argp
);
1383 case SNDRV_CTL_IOCTL_ELEM_LIST
:
1384 return snd_ctl_elem_list(card
, argp
);
1385 case SNDRV_CTL_IOCTL_ELEM_INFO
:
1386 return snd_ctl_elem_info_user(ctl
, argp
);
1387 case SNDRV_CTL_IOCTL_ELEM_READ
:
1388 return snd_ctl_elem_read_user(card
, argp
);
1389 case SNDRV_CTL_IOCTL_ELEM_WRITE
:
1390 return snd_ctl_elem_write_user(ctl
, argp
);
1391 case SNDRV_CTL_IOCTL_ELEM_LOCK
:
1392 return snd_ctl_elem_lock(ctl
, argp
);
1393 case SNDRV_CTL_IOCTL_ELEM_UNLOCK
:
1394 return snd_ctl_elem_unlock(ctl
, argp
);
1395 case SNDRV_CTL_IOCTL_ELEM_ADD
:
1396 return snd_ctl_elem_add_user(ctl
, argp
, 0);
1397 case SNDRV_CTL_IOCTL_ELEM_REPLACE
:
1398 return snd_ctl_elem_add_user(ctl
, argp
, 1);
1399 case SNDRV_CTL_IOCTL_ELEM_REMOVE
:
1400 return snd_ctl_elem_remove(ctl
, argp
);
1401 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS
:
1402 return snd_ctl_subscribe_events(ctl
, ip
);
1403 case SNDRV_CTL_IOCTL_TLV_READ
:
1404 return snd_ctl_tlv_ioctl(ctl
, argp
, 0);
1405 case SNDRV_CTL_IOCTL_TLV_WRITE
:
1406 return snd_ctl_tlv_ioctl(ctl
, argp
, 1);
1407 case SNDRV_CTL_IOCTL_TLV_COMMAND
:
1408 return snd_ctl_tlv_ioctl(ctl
, argp
, -1);
1409 case SNDRV_CTL_IOCTL_POWER
:
1410 return -ENOPROTOOPT
;
1411 case SNDRV_CTL_IOCTL_POWER_STATE
:
1413 return put_user(card
->power_state
, ip
) ? -EFAULT
: 0;
1415 return put_user(SNDRV_CTL_POWER_D0
, ip
) ? -EFAULT
: 0;
1418 down_read(&snd_ioctl_rwsem
);
1419 list_for_each_entry(p
, &snd_control_ioctls
, list
) {
1420 err
= p
->fioctl(card
, ctl
, cmd
, arg
);
1421 if (err
!= -ENOIOCTLCMD
) {
1422 up_read(&snd_ioctl_rwsem
);
1426 up_read(&snd_ioctl_rwsem
);
1427 dev_dbg(card
->dev
, "unknown ioctl = 0x%x\n", cmd
);
1431 static ssize_t
snd_ctl_read(struct file
*file
, char __user
*buffer
,
1432 size_t count
, loff_t
* offset
)
1434 struct snd_ctl_file
*ctl
;
1438 ctl
= file
->private_data
;
1439 if (snd_BUG_ON(!ctl
|| !ctl
->card
))
1441 if (!ctl
->subscribed
)
1443 if (count
< sizeof(struct snd_ctl_event
))
1445 spin_lock_irq(&ctl
->read_lock
);
1446 while (count
>= sizeof(struct snd_ctl_event
)) {
1447 struct snd_ctl_event ev
;
1448 struct snd_kctl_event
*kev
;
1449 while (list_empty(&ctl
->events
)) {
1451 if ((file
->f_flags
& O_NONBLOCK
) != 0 || result
> 0) {
1455 init_waitqueue_entry(&wait
, current
);
1456 add_wait_queue(&ctl
->change_sleep
, &wait
);
1457 set_current_state(TASK_INTERRUPTIBLE
);
1458 spin_unlock_irq(&ctl
->read_lock
);
1460 remove_wait_queue(&ctl
->change_sleep
, &wait
);
1461 if (ctl
->card
->shutdown
)
1463 if (signal_pending(current
))
1464 return -ERESTARTSYS
;
1465 spin_lock_irq(&ctl
->read_lock
);
1467 kev
= snd_kctl_event(ctl
->events
.next
);
1468 ev
.type
= SNDRV_CTL_EVENT_ELEM
;
1469 ev
.data
.elem
.mask
= kev
->mask
;
1470 ev
.data
.elem
.id
= kev
->id
;
1471 list_del(&kev
->list
);
1472 spin_unlock_irq(&ctl
->read_lock
);
1474 if (copy_to_user(buffer
, &ev
, sizeof(struct snd_ctl_event
))) {
1478 spin_lock_irq(&ctl
->read_lock
);
1479 buffer
+= sizeof(struct snd_ctl_event
);
1480 count
-= sizeof(struct snd_ctl_event
);
1481 result
+= sizeof(struct snd_ctl_event
);
1484 spin_unlock_irq(&ctl
->read_lock
);
1486 return result
> 0 ? result
: err
;
1489 static unsigned int snd_ctl_poll(struct file
*file
, poll_table
* wait
)
1492 struct snd_ctl_file
*ctl
;
1494 ctl
= file
->private_data
;
1495 if (!ctl
->subscribed
)
1497 poll_wait(file
, &ctl
->change_sleep
, wait
);
1500 if (!list_empty(&ctl
->events
))
1501 mask
|= POLLIN
| POLLRDNORM
;
1507 * register the device-specific control-ioctls.
1508 * called from each device manager like pcm.c, hwdep.c, etc.
1510 static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn
, struct list_head
*lists
)
1512 struct snd_kctl_ioctl
*pn
;
1514 pn
= kzalloc(sizeof(struct snd_kctl_ioctl
), GFP_KERNEL
);
1518 down_write(&snd_ioctl_rwsem
);
1519 list_add_tail(&pn
->list
, lists
);
1520 up_write(&snd_ioctl_rwsem
);
1524 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn
)
1526 return _snd_ctl_register_ioctl(fcn
, &snd_control_ioctls
);
1529 EXPORT_SYMBOL(snd_ctl_register_ioctl
);
1531 #ifdef CONFIG_COMPAT
1532 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn
)
1534 return _snd_ctl_register_ioctl(fcn
, &snd_control_compat_ioctls
);
1537 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat
);
1541 * de-register the device-specific control-ioctls.
1543 static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn
,
1544 struct list_head
*lists
)
1546 struct snd_kctl_ioctl
*p
;
1548 if (snd_BUG_ON(!fcn
))
1550 down_write(&snd_ioctl_rwsem
);
1551 list_for_each_entry(p
, lists
, list
) {
1552 if (p
->fioctl
== fcn
) {
1554 up_write(&snd_ioctl_rwsem
);
1559 up_write(&snd_ioctl_rwsem
);
1564 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn
)
1566 return _snd_ctl_unregister_ioctl(fcn
, &snd_control_ioctls
);
1569 EXPORT_SYMBOL(snd_ctl_unregister_ioctl
);
1571 #ifdef CONFIG_COMPAT
1572 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn
)
1574 return _snd_ctl_unregister_ioctl(fcn
, &snd_control_compat_ioctls
);
1577 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat
);
1580 static int snd_ctl_fasync(int fd
, struct file
* file
, int on
)
1582 struct snd_ctl_file
*ctl
;
1584 ctl
= file
->private_data
;
1585 return fasync_helper(fd
, file
, on
, &ctl
->fasync
);
1591 #ifdef CONFIG_COMPAT
1592 #include "control_compat.c"
1594 #define snd_ctl_ioctl_compat NULL
1601 static const struct file_operations snd_ctl_f_ops
=
1603 .owner
= THIS_MODULE
,
1604 .read
= snd_ctl_read
,
1605 .open
= snd_ctl_open
,
1606 .release
= snd_ctl_release
,
1607 .llseek
= no_llseek
,
1608 .poll
= snd_ctl_poll
,
1609 .unlocked_ioctl
= snd_ctl_ioctl
,
1610 .compat_ioctl
= snd_ctl_ioctl_compat
,
1611 .fasync
= snd_ctl_fasync
,
1615 * registration of the control device
1617 static int snd_ctl_dev_register(struct snd_device
*device
)
1619 struct snd_card
*card
= device
->device_data
;
1623 if (snd_BUG_ON(!card
))
1625 cardnum
= card
->number
;
1626 if (snd_BUG_ON(cardnum
< 0 || cardnum
>= SNDRV_CARDS
))
1628 sprintf(name
, "controlC%i", cardnum
);
1629 if ((err
= snd_register_device(SNDRV_DEVICE_TYPE_CONTROL
, card
, -1,
1630 &snd_ctl_f_ops
, card
, name
)) < 0)
1636 * disconnection of the control device
1638 static int snd_ctl_dev_disconnect(struct snd_device
*device
)
1640 struct snd_card
*card
= device
->device_data
;
1641 struct snd_ctl_file
*ctl
;
1644 if (snd_BUG_ON(!card
))
1646 cardnum
= card
->number
;
1647 if (snd_BUG_ON(cardnum
< 0 || cardnum
>= SNDRV_CARDS
))
1650 read_lock(&card
->ctl_files_rwlock
);
1651 list_for_each_entry(ctl
, &card
->ctl_files
, list
) {
1652 wake_up(&ctl
->change_sleep
);
1653 kill_fasync(&ctl
->fasync
, SIGIO
, POLL_ERR
);
1655 read_unlock(&card
->ctl_files_rwlock
);
1657 if ((err
= snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL
,
1666 static int snd_ctl_dev_free(struct snd_device
*device
)
1668 struct snd_card
*card
= device
->device_data
;
1669 struct snd_kcontrol
*control
;
1671 down_write(&card
->controls_rwsem
);
1672 while (!list_empty(&card
->controls
)) {
1673 control
= snd_kcontrol(card
->controls
.next
);
1674 snd_ctl_remove(card
, control
);
1676 up_write(&card
->controls_rwsem
);
1681 * create control core:
1682 * called from init.c
1684 int snd_ctl_create(struct snd_card
*card
)
1686 static struct snd_device_ops ops
= {
1687 .dev_free
= snd_ctl_dev_free
,
1688 .dev_register
= snd_ctl_dev_register
,
1689 .dev_disconnect
= snd_ctl_dev_disconnect
,
1692 if (snd_BUG_ON(!card
))
1694 return snd_device_new(card
, SNDRV_DEV_CONTROL
, card
, &ops
);
1698 * Frequently used control callbacks/helpers
1700 int snd_ctl_boolean_mono_info(struct snd_kcontrol
*kcontrol
,
1701 struct snd_ctl_elem_info
*uinfo
)
1703 uinfo
->type
= SNDRV_CTL_ELEM_TYPE_BOOLEAN
;
1705 uinfo
->value
.integer
.min
= 0;
1706 uinfo
->value
.integer
.max
= 1;
1710 EXPORT_SYMBOL(snd_ctl_boolean_mono_info
);
1712 int snd_ctl_boolean_stereo_info(struct snd_kcontrol
*kcontrol
,
1713 struct snd_ctl_elem_info
*uinfo
)
1715 uinfo
->type
= SNDRV_CTL_ELEM_TYPE_BOOLEAN
;
1717 uinfo
->value
.integer
.min
= 0;
1718 uinfo
->value
.integer
.max
= 1;
1722 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info
);
1725 * snd_ctl_enum_info - fills the info structure for an enumerated control
1726 * @info: the structure to be filled
1727 * @channels: the number of the control's channels; often one
1728 * @items: the number of control values; also the size of @names
1729 * @names: an array containing the names of all control values
1731 * Sets all required fields in @info to their appropriate values.
1732 * If the control's accessibility is not the default (readable and writable),
1733 * the caller has to fill @info->access.
1737 int snd_ctl_enum_info(struct snd_ctl_elem_info
*info
, unsigned int channels
,
1738 unsigned int items
, const char *const names
[])
1740 info
->type
= SNDRV_CTL_ELEM_TYPE_ENUMERATED
;
1741 info
->count
= channels
;
1742 info
->value
.enumerated
.items
= items
;
1743 if (info
->value
.enumerated
.item
>= items
)
1744 info
->value
.enumerated
.item
= items
- 1;
1745 strlcpy(info
->value
.enumerated
.name
,
1746 names
[info
->value
.enumerated
.item
],
1747 sizeof(info
->value
.enumerated
.name
));
1750 EXPORT_SYMBOL(snd_ctl_enum_info
);