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 for (i
= 0; i
< SND_CTL_SUBDEV_ITEMS
; i
++)
83 ctl
->preferred_subdevice
[i
] = -1;
84 ctl
->pid
= get_pid(task_pid(current
));
85 file
->private_data
= ctl
;
86 write_lock_irqsave(&card
->ctl_files_rwlock
, flags
);
87 list_add_tail(&ctl
->list
, &card
->ctl_files
);
88 write_unlock_irqrestore(&card
->ctl_files_rwlock
, flags
);
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
);
145 * snd_ctl_notify - Send notification to user-space for a control change
146 * @card: the card to send notification
147 * @mask: the event mask, SNDRV_CTL_EVENT_*
148 * @id: the ctl element id to send notification
150 * This function adds an event record with the given id and mask, appends
151 * to the list and wakes up the user-space for notification. This can be
152 * called in the atomic context.
154 void snd_ctl_notify(struct snd_card
*card
, unsigned int mask
,
155 struct snd_ctl_elem_id
*id
)
158 struct snd_ctl_file
*ctl
;
159 struct snd_kctl_event
*ev
;
161 if (snd_BUG_ON(!card
|| !id
))
163 read_lock(&card
->ctl_files_rwlock
);
164 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
165 card
->mixer_oss_change_count
++;
167 list_for_each_entry(ctl
, &card
->ctl_files
, list
) {
168 if (!ctl
->subscribed
)
170 spin_lock_irqsave(&ctl
->read_lock
, flags
);
171 list_for_each_entry(ev
, &ctl
->events
, list
) {
172 if (ev
->id
.numid
== id
->numid
) {
177 ev
= kzalloc(sizeof(*ev
), GFP_ATOMIC
);
181 list_add_tail(&ev
->list
, &ctl
->events
);
183 dev_err(card
->dev
, "No memory available to allocate event\n");
186 wake_up(&ctl
->change_sleep
);
187 spin_unlock_irqrestore(&ctl
->read_lock
, flags
);
188 kill_fasync(&ctl
->fasync
, SIGIO
, POLL_IN
);
190 read_unlock(&card
->ctl_files_rwlock
);
192 EXPORT_SYMBOL(snd_ctl_notify
);
195 * snd_ctl_new - create a new control instance with some elements
196 * @kctl: the pointer to store new control instance
197 * @count: the number of elements in this control
198 * @access: the default access flags for elements in this control
199 * @file: given when locking these elements
201 * Allocates a memory object for a new control instance. The instance has
202 * elements as many as the given number (@count). Each element has given
203 * access permissions (@access). Each element is locked when @file is given.
205 * Return: 0 on success, error code on failure
207 static int snd_ctl_new(struct snd_kcontrol
**kctl
, unsigned int count
,
208 unsigned int access
, struct snd_ctl_file
*file
)
213 if (count
== 0 || count
> MAX_CONTROL_COUNT
)
216 size
= sizeof(struct snd_kcontrol
);
217 size
+= sizeof(struct snd_kcontrol_volatile
) * count
;
219 *kctl
= kzalloc(size
, GFP_KERNEL
);
221 pr_err("ALSA: Cannot allocate control instance\n");
225 for (idx
= 0; idx
< count
; idx
++) {
226 (*kctl
)->vd
[idx
].access
= access
;
227 (*kctl
)->vd
[idx
].owner
= file
;
229 (*kctl
)->count
= count
;
235 * snd_ctl_new1 - create a control instance from the template
236 * @ncontrol: the initialization record
237 * @private_data: the private data to set
239 * Allocates a new struct snd_kcontrol instance and initialize from the given
240 * template. When the access field of ncontrol is 0, it's assumed as
241 * READWRITE access. When the count field is 0, it's assumes as one.
243 * Return: The pointer of the newly generated instance, or %NULL on failure.
245 struct snd_kcontrol
*snd_ctl_new1(const struct snd_kcontrol_new
*ncontrol
,
248 struct snd_kcontrol
*kctl
;
253 if (snd_BUG_ON(!ncontrol
|| !ncontrol
->info
))
256 count
= ncontrol
->count
;
260 access
= ncontrol
->access
;
262 access
= SNDRV_CTL_ELEM_ACCESS_READWRITE
;
263 access
&= (SNDRV_CTL_ELEM_ACCESS_READWRITE
|
264 SNDRV_CTL_ELEM_ACCESS_VOLATILE
|
265 SNDRV_CTL_ELEM_ACCESS_INACTIVE
|
266 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE
|
267 SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND
|
268 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK
);
270 err
= snd_ctl_new(&kctl
, count
, access
, NULL
);
274 /* The 'numid' member is decided when calling snd_ctl_add(). */
275 kctl
->id
.iface
= ncontrol
->iface
;
276 kctl
->id
.device
= ncontrol
->device
;
277 kctl
->id
.subdevice
= ncontrol
->subdevice
;
278 if (ncontrol
->name
) {
279 strlcpy(kctl
->id
.name
, ncontrol
->name
, sizeof(kctl
->id
.name
));
280 if (strcmp(ncontrol
->name
, kctl
->id
.name
) != 0)
281 pr_warn("ALSA: Control name '%s' truncated to '%s'\n",
282 ncontrol
->name
, kctl
->id
.name
);
284 kctl
->id
.index
= ncontrol
->index
;
286 kctl
->info
= ncontrol
->info
;
287 kctl
->get
= ncontrol
->get
;
288 kctl
->put
= ncontrol
->put
;
289 kctl
->tlv
.p
= ncontrol
->tlv
.p
;
291 kctl
->private_value
= ncontrol
->private_value
;
292 kctl
->private_data
= private_data
;
296 EXPORT_SYMBOL(snd_ctl_new1
);
299 * snd_ctl_free_one - release the control instance
300 * @kcontrol: the control instance
302 * Releases the control instance created via snd_ctl_new()
304 * Don't call this after the control was added to the card.
306 void snd_ctl_free_one(struct snd_kcontrol
*kcontrol
)
309 if (kcontrol
->private_free
)
310 kcontrol
->private_free(kcontrol
);
314 EXPORT_SYMBOL(snd_ctl_free_one
);
316 static bool snd_ctl_remove_numid_conflict(struct snd_card
*card
,
319 struct snd_kcontrol
*kctl
;
321 /* Make sure that the ids assigned to the control do not wrap around */
322 if (card
->last_numid
>= UINT_MAX
- count
)
323 card
->last_numid
= 0;
325 list_for_each_entry(kctl
, &card
->controls
, list
) {
326 if (kctl
->id
.numid
< card
->last_numid
+ 1 + count
&&
327 kctl
->id
.numid
+ kctl
->count
> card
->last_numid
+ 1) {
328 card
->last_numid
= kctl
->id
.numid
+ kctl
->count
- 1;
335 static int snd_ctl_find_hole(struct snd_card
*card
, unsigned int count
)
337 unsigned int iter
= 100000;
339 while (snd_ctl_remove_numid_conflict(card
, count
)) {
341 /* this situation is very unlikely */
342 dev_err(card
->dev
, "unable to allocate new control numid\n");
350 * snd_ctl_add - add the control instance to the card
351 * @card: the card instance
352 * @kcontrol: the control instance to add
354 * Adds the control instance created via snd_ctl_new() or
355 * snd_ctl_new1() to the given card. Assigns also an unique
356 * numid used for fast search.
358 * It frees automatically the control which cannot be added.
360 * Return: Zero if successful, or a negative error code on failure.
363 int snd_ctl_add(struct snd_card
*card
, struct snd_kcontrol
*kcontrol
)
365 struct snd_ctl_elem_id id
;
372 if (snd_BUG_ON(!card
|| !kcontrol
->info
))
375 if (id
.index
> UINT_MAX
- kcontrol
->count
)
378 down_write(&card
->controls_rwsem
);
379 if (snd_ctl_find_id(card
, &id
)) {
380 up_write(&card
->controls_rwsem
);
381 dev_err(card
->dev
, "control %i:%i:%i:%s:%i is already present\n",
390 if (snd_ctl_find_hole(card
, kcontrol
->count
) < 0) {
391 up_write(&card
->controls_rwsem
);
395 list_add_tail(&kcontrol
->list
, &card
->controls
);
396 card
->controls_count
+= kcontrol
->count
;
397 kcontrol
->id
.numid
= card
->last_numid
+ 1;
398 card
->last_numid
+= kcontrol
->count
;
400 count
= kcontrol
->count
;
401 up_write(&card
->controls_rwsem
);
402 for (idx
= 0; idx
< count
; idx
++, id
.index
++, id
.numid
++)
403 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_ADD
, &id
);
407 snd_ctl_free_one(kcontrol
);
410 EXPORT_SYMBOL(snd_ctl_add
);
413 * snd_ctl_replace - replace the control instance of the card
414 * @card: the card instance
415 * @kcontrol: the control instance to replace
416 * @add_on_replace: add the control if not already added
418 * Replaces the given control. If the given control does not exist
419 * and the add_on_replace flag is set, the control is added. If the
420 * control exists, it is destroyed first.
422 * It frees automatically the control which cannot be added or replaced.
424 * Return: Zero if successful, or a negative error code on failure.
426 int snd_ctl_replace(struct snd_card
*card
, struct snd_kcontrol
*kcontrol
,
429 struct snd_ctl_elem_id id
;
432 struct snd_kcontrol
*old
;
437 if (snd_BUG_ON(!card
|| !kcontrol
->info
)) {
442 down_write(&card
->controls_rwsem
);
443 old
= snd_ctl_find_id(card
, &id
);
447 up_write(&card
->controls_rwsem
);
451 ret
= snd_ctl_remove(card
, old
);
453 up_write(&card
->controls_rwsem
);
457 if (snd_ctl_find_hole(card
, kcontrol
->count
) < 0) {
458 up_write(&card
->controls_rwsem
);
462 list_add_tail(&kcontrol
->list
, &card
->controls
);
463 card
->controls_count
+= kcontrol
->count
;
464 kcontrol
->id
.numid
= card
->last_numid
+ 1;
465 card
->last_numid
+= kcontrol
->count
;
467 count
= kcontrol
->count
;
468 up_write(&card
->controls_rwsem
);
469 for (idx
= 0; idx
< count
; idx
++, id
.index
++, id
.numid
++)
470 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_ADD
, &id
);
474 snd_ctl_free_one(kcontrol
);
477 EXPORT_SYMBOL(snd_ctl_replace
);
480 * snd_ctl_remove - remove the control from the card and release it
481 * @card: the card instance
482 * @kcontrol: the control instance to remove
484 * Removes the control from the card and then releases the instance.
485 * You don't need to call snd_ctl_free_one(). You must be in
486 * the write lock - down_write(&card->controls_rwsem).
488 * Return: 0 if successful, or a negative error code on failure.
490 int snd_ctl_remove(struct snd_card
*card
, struct snd_kcontrol
*kcontrol
)
492 struct snd_ctl_elem_id id
;
495 if (snd_BUG_ON(!card
|| !kcontrol
))
497 list_del(&kcontrol
->list
);
498 card
->controls_count
-= kcontrol
->count
;
500 for (idx
= 0; idx
< kcontrol
->count
; idx
++, id
.index
++, id
.numid
++)
501 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_REMOVE
, &id
);
502 snd_ctl_free_one(kcontrol
);
505 EXPORT_SYMBOL(snd_ctl_remove
);
508 * snd_ctl_remove_id - remove the control of the given id and release it
509 * @card: the card instance
510 * @id: the control id to remove
512 * Finds the control instance with the given id, removes it from the
513 * card list and releases it.
515 * Return: 0 if successful, or a negative error code on failure.
517 int snd_ctl_remove_id(struct snd_card
*card
, struct snd_ctl_elem_id
*id
)
519 struct snd_kcontrol
*kctl
;
522 down_write(&card
->controls_rwsem
);
523 kctl
= snd_ctl_find_id(card
, id
);
525 up_write(&card
->controls_rwsem
);
528 ret
= snd_ctl_remove(card
, kctl
);
529 up_write(&card
->controls_rwsem
);
532 EXPORT_SYMBOL(snd_ctl_remove_id
);
535 * snd_ctl_remove_user_ctl - remove and release the unlocked user control
536 * @file: active control handle
537 * @id: the control id to remove
539 * Finds the control instance with the given id, removes it from the
540 * card list and releases it.
542 * Return: 0 if successful, or a negative error code on failure.
544 static int snd_ctl_remove_user_ctl(struct snd_ctl_file
* file
,
545 struct snd_ctl_elem_id
*id
)
547 struct snd_card
*card
= file
->card
;
548 struct snd_kcontrol
*kctl
;
551 down_write(&card
->controls_rwsem
);
552 kctl
= snd_ctl_find_id(card
, id
);
557 if (!(kctl
->vd
[0].access
& SNDRV_CTL_ELEM_ACCESS_USER
)) {
561 for (idx
= 0; idx
< kctl
->count
; idx
++)
562 if (kctl
->vd
[idx
].owner
!= NULL
&& kctl
->vd
[idx
].owner
!= file
) {
566 ret
= snd_ctl_remove(card
, kctl
);
569 card
->user_ctl_count
--;
571 up_write(&card
->controls_rwsem
);
576 * snd_ctl_activate_id - activate/inactivate the control of the given id
577 * @card: the card instance
578 * @id: the control id to activate/inactivate
579 * @active: non-zero to activate
581 * Finds the control instance with the given id, and activate or
582 * inactivate the control together with notification, if changed.
584 * Return: 0 if unchanged, 1 if changed, or a negative error code on failure.
586 int snd_ctl_activate_id(struct snd_card
*card
, struct snd_ctl_elem_id
*id
,
589 struct snd_kcontrol
*kctl
;
590 struct snd_kcontrol_volatile
*vd
;
591 unsigned int index_offset
;
594 down_write(&card
->controls_rwsem
);
595 kctl
= snd_ctl_find_id(card
, id
);
600 index_offset
= snd_ctl_get_ioff(kctl
, id
);
601 vd
= &kctl
->vd
[index_offset
];
604 if (!(vd
->access
& SNDRV_CTL_ELEM_ACCESS_INACTIVE
))
606 vd
->access
&= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE
;
608 if (vd
->access
& SNDRV_CTL_ELEM_ACCESS_INACTIVE
)
610 vd
->access
|= SNDRV_CTL_ELEM_ACCESS_INACTIVE
;
614 up_write(&card
->controls_rwsem
);
616 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_INFO
, id
);
619 EXPORT_SYMBOL_GPL(snd_ctl_activate_id
);
622 * snd_ctl_rename_id - replace the id of a control on the card
623 * @card: the card instance
624 * @src_id: the old id
625 * @dst_id: the new id
627 * Finds the control with the old id from the card, and replaces the
628 * id with the new one.
630 * Return: Zero if successful, or a negative error code on failure.
632 int snd_ctl_rename_id(struct snd_card
*card
, struct snd_ctl_elem_id
*src_id
,
633 struct snd_ctl_elem_id
*dst_id
)
635 struct snd_kcontrol
*kctl
;
637 down_write(&card
->controls_rwsem
);
638 kctl
= snd_ctl_find_id(card
, src_id
);
640 up_write(&card
->controls_rwsem
);
644 kctl
->id
.numid
= card
->last_numid
+ 1;
645 card
->last_numid
+= kctl
->count
;
646 up_write(&card
->controls_rwsem
);
649 EXPORT_SYMBOL(snd_ctl_rename_id
);
652 * snd_ctl_find_numid - find the control instance with the given number-id
653 * @card: the card instance
654 * @numid: the number-id to search
656 * Finds the control instance with the given number-id from the card.
658 * The caller must down card->controls_rwsem before calling this function
659 * (if the race condition can happen).
661 * Return: The pointer of the instance if found, or %NULL if not.
664 struct snd_kcontrol
*snd_ctl_find_numid(struct snd_card
*card
, unsigned int numid
)
666 struct snd_kcontrol
*kctl
;
668 if (snd_BUG_ON(!card
|| !numid
))
670 list_for_each_entry(kctl
, &card
->controls
, list
) {
671 if (kctl
->id
.numid
<= numid
&& kctl
->id
.numid
+ kctl
->count
> numid
)
676 EXPORT_SYMBOL(snd_ctl_find_numid
);
679 * snd_ctl_find_id - find the control instance with the given id
680 * @card: the card instance
681 * @id: the id to search
683 * Finds the control instance with the given id from the card.
685 * The caller must down card->controls_rwsem before calling this function
686 * (if the race condition can happen).
688 * Return: The pointer of the instance if found, or %NULL if not.
691 struct snd_kcontrol
*snd_ctl_find_id(struct snd_card
*card
,
692 struct snd_ctl_elem_id
*id
)
694 struct snd_kcontrol
*kctl
;
696 if (snd_BUG_ON(!card
|| !id
))
699 return snd_ctl_find_numid(card
, id
->numid
);
700 list_for_each_entry(kctl
, &card
->controls
, list
) {
701 if (kctl
->id
.iface
!= id
->iface
)
703 if (kctl
->id
.device
!= id
->device
)
705 if (kctl
->id
.subdevice
!= id
->subdevice
)
707 if (strncmp(kctl
->id
.name
, id
->name
, sizeof(kctl
->id
.name
)))
709 if (kctl
->id
.index
> id
->index
)
711 if (kctl
->id
.index
+ kctl
->count
<= id
->index
)
717 EXPORT_SYMBOL(snd_ctl_find_id
);
719 static int snd_ctl_card_info(struct snd_card
*card
, struct snd_ctl_file
* ctl
,
720 unsigned int cmd
, void __user
*arg
)
722 struct snd_ctl_card_info
*info
;
724 info
= kzalloc(sizeof(*info
), GFP_KERNEL
);
727 down_read(&snd_ioctl_rwsem
);
728 info
->card
= card
->number
;
729 strlcpy(info
->id
, card
->id
, sizeof(info
->id
));
730 strlcpy(info
->driver
, card
->driver
, sizeof(info
->driver
));
731 strlcpy(info
->name
, card
->shortname
, sizeof(info
->name
));
732 strlcpy(info
->longname
, card
->longname
, sizeof(info
->longname
));
733 strlcpy(info
->mixername
, card
->mixername
, sizeof(info
->mixername
));
734 strlcpy(info
->components
, card
->components
, sizeof(info
->components
));
735 up_read(&snd_ioctl_rwsem
);
736 if (copy_to_user(arg
, info
, sizeof(struct snd_ctl_card_info
))) {
744 static int snd_ctl_elem_list(struct snd_card
*card
,
745 struct snd_ctl_elem_list __user
*_list
)
747 struct list_head
*plist
;
748 struct snd_ctl_elem_list list
;
749 struct snd_kcontrol
*kctl
;
750 struct snd_ctl_elem_id
*dst
, *id
;
751 unsigned int offset
, space
, jidx
;
753 if (copy_from_user(&list
, _list
, sizeof(list
)))
755 offset
= list
.offset
;
757 /* try limit maximum space */
761 /* allocate temporary buffer for atomic operation */
762 dst
= vmalloc(space
* sizeof(struct snd_ctl_elem_id
));
765 down_read(&card
->controls_rwsem
);
766 list
.count
= card
->controls_count
;
767 plist
= card
->controls
.next
;
768 while (plist
!= &card
->controls
) {
771 kctl
= snd_kcontrol(plist
);
772 if (offset
< kctl
->count
)
774 offset
-= kctl
->count
;
779 while (space
> 0 && plist
!= &card
->controls
) {
780 kctl
= snd_kcontrol(plist
);
781 for (jidx
= offset
; space
> 0 && jidx
< kctl
->count
; jidx
++) {
782 snd_ctl_build_ioff(id
, kctl
, jidx
);
790 up_read(&card
->controls_rwsem
);
792 copy_to_user(list
.pids
, dst
,
793 list
.used
* sizeof(struct snd_ctl_elem_id
))) {
799 down_read(&card
->controls_rwsem
);
800 list
.count
= card
->controls_count
;
801 up_read(&card
->controls_rwsem
);
803 if (copy_to_user(_list
, &list
, sizeof(list
)))
808 static int snd_ctl_elem_info(struct snd_ctl_file
*ctl
,
809 struct snd_ctl_elem_info
*info
)
811 struct snd_card
*card
= ctl
->card
;
812 struct snd_kcontrol
*kctl
;
813 struct snd_kcontrol_volatile
*vd
;
814 unsigned int index_offset
;
817 down_read(&card
->controls_rwsem
);
818 kctl
= snd_ctl_find_id(card
, &info
->id
);
820 up_read(&card
->controls_rwsem
);
823 #ifdef CONFIG_SND_DEBUG
826 result
= kctl
->info(kctl
, info
);
828 snd_BUG_ON(info
->access
);
829 index_offset
= snd_ctl_get_ioff(kctl
, &info
->id
);
830 vd
= &kctl
->vd
[index_offset
];
831 snd_ctl_build_ioff(&info
->id
, kctl
, index_offset
);
832 info
->access
= vd
->access
;
834 info
->access
|= SNDRV_CTL_ELEM_ACCESS_LOCK
;
835 if (vd
->owner
== ctl
)
836 info
->access
|= SNDRV_CTL_ELEM_ACCESS_OWNER
;
837 info
->owner
= pid_vnr(vd
->owner
->pid
);
842 up_read(&card
->controls_rwsem
);
846 static int snd_ctl_elem_info_user(struct snd_ctl_file
*ctl
,
847 struct snd_ctl_elem_info __user
*_info
)
849 struct snd_ctl_elem_info info
;
852 if (copy_from_user(&info
, _info
, sizeof(info
)))
854 snd_power_lock(ctl
->card
);
855 result
= snd_power_wait(ctl
->card
, SNDRV_CTL_POWER_D0
);
857 result
= snd_ctl_elem_info(ctl
, &info
);
858 snd_power_unlock(ctl
->card
);
860 if (copy_to_user(_info
, &info
, sizeof(info
)))
865 static int snd_ctl_elem_read(struct snd_card
*card
,
866 struct snd_ctl_elem_value
*control
)
868 struct snd_kcontrol
*kctl
;
869 struct snd_kcontrol_volatile
*vd
;
870 unsigned int index_offset
;
873 down_read(&card
->controls_rwsem
);
874 kctl
= snd_ctl_find_id(card
, &control
->id
);
878 index_offset
= snd_ctl_get_ioff(kctl
, &control
->id
);
879 vd
= &kctl
->vd
[index_offset
];
880 if ((vd
->access
& SNDRV_CTL_ELEM_ACCESS_READ
) &&
882 snd_ctl_build_ioff(&control
->id
, kctl
, index_offset
);
883 result
= kctl
->get(kctl
, control
);
887 up_read(&card
->controls_rwsem
);
891 static int snd_ctl_elem_read_user(struct snd_card
*card
,
892 struct snd_ctl_elem_value __user
*_control
)
894 struct snd_ctl_elem_value
*control
;
897 control
= memdup_user(_control
, sizeof(*control
));
899 return PTR_ERR(control
);
901 snd_power_lock(card
);
902 result
= snd_power_wait(card
, SNDRV_CTL_POWER_D0
);
904 result
= snd_ctl_elem_read(card
, control
);
905 snd_power_unlock(card
);
907 if (copy_to_user(_control
, control
, sizeof(*control
)))
913 static int snd_ctl_elem_write(struct snd_card
*card
, struct snd_ctl_file
*file
,
914 struct snd_ctl_elem_value
*control
)
916 struct snd_kcontrol
*kctl
;
917 struct snd_kcontrol_volatile
*vd
;
918 unsigned int index_offset
;
921 down_read(&card
->controls_rwsem
);
922 kctl
= snd_ctl_find_id(card
, &control
->id
);
926 index_offset
= snd_ctl_get_ioff(kctl
, &control
->id
);
927 vd
= &kctl
->vd
[index_offset
];
928 if (!(vd
->access
& SNDRV_CTL_ELEM_ACCESS_WRITE
) ||
930 (file
&& vd
->owner
&& vd
->owner
!= file
)) {
933 snd_ctl_build_ioff(&control
->id
, kctl
, index_offset
);
934 result
= kctl
->put(kctl
, control
);
937 struct snd_ctl_elem_id id
= control
->id
;
938 up_read(&card
->controls_rwsem
);
939 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_VALUE
, &id
);
943 up_read(&card
->controls_rwsem
);
947 static int snd_ctl_elem_write_user(struct snd_ctl_file
*file
,
948 struct snd_ctl_elem_value __user
*_control
)
950 struct snd_ctl_elem_value
*control
;
951 struct snd_card
*card
;
954 control
= memdup_user(_control
, sizeof(*control
));
956 return PTR_ERR(control
);
959 snd_power_lock(card
);
960 result
= snd_power_wait(card
, SNDRV_CTL_POWER_D0
);
962 result
= snd_ctl_elem_write(card
, file
, control
);
963 snd_power_unlock(card
);
965 if (copy_to_user(_control
, control
, sizeof(*control
)))
971 static int snd_ctl_elem_lock(struct snd_ctl_file
*file
,
972 struct snd_ctl_elem_id __user
*_id
)
974 struct snd_card
*card
= file
->card
;
975 struct snd_ctl_elem_id id
;
976 struct snd_kcontrol
*kctl
;
977 struct snd_kcontrol_volatile
*vd
;
980 if (copy_from_user(&id
, _id
, sizeof(id
)))
982 down_write(&card
->controls_rwsem
);
983 kctl
= snd_ctl_find_id(card
, &id
);
987 vd
= &kctl
->vd
[snd_ctl_get_ioff(kctl
, &id
)];
988 if (vd
->owner
!= NULL
)
995 up_write(&card
->controls_rwsem
);
999 static int snd_ctl_elem_unlock(struct snd_ctl_file
*file
,
1000 struct snd_ctl_elem_id __user
*_id
)
1002 struct snd_card
*card
= file
->card
;
1003 struct snd_ctl_elem_id id
;
1004 struct snd_kcontrol
*kctl
;
1005 struct snd_kcontrol_volatile
*vd
;
1008 if (copy_from_user(&id
, _id
, sizeof(id
)))
1010 down_write(&card
->controls_rwsem
);
1011 kctl
= snd_ctl_find_id(card
, &id
);
1015 vd
= &kctl
->vd
[snd_ctl_get_ioff(kctl
, &id
)];
1016 if (vd
->owner
== NULL
)
1018 else if (vd
->owner
!= file
)
1025 up_write(&card
->controls_rwsem
);
1029 struct user_element
{
1030 struct snd_ctl_elem_info info
;
1031 struct snd_card
*card
;
1032 void *elem_data
; /* element data */
1033 unsigned long elem_data_size
; /* size of element data in bytes */
1034 void *tlv_data
; /* TLV data */
1035 unsigned long tlv_data_size
; /* TLV data size */
1036 void *priv_data
; /* private data (like strings for enumerated type) */
1039 static int snd_ctl_elem_user_info(struct snd_kcontrol
*kcontrol
,
1040 struct snd_ctl_elem_info
*uinfo
)
1042 struct user_element
*ue
= kcontrol
->private_data
;
1048 static int snd_ctl_elem_user_enum_info(struct snd_kcontrol
*kcontrol
,
1049 struct snd_ctl_elem_info
*uinfo
)
1051 struct user_element
*ue
= kcontrol
->private_data
;
1055 item
= uinfo
->value
.enumerated
.item
;
1059 item
= min(item
, uinfo
->value
.enumerated
.items
- 1);
1060 uinfo
->value
.enumerated
.item
= item
;
1062 names
= ue
->priv_data
;
1063 for (; item
> 0; --item
)
1064 names
+= strlen(names
) + 1;
1065 strcpy(uinfo
->value
.enumerated
.name
, names
);
1070 static int snd_ctl_elem_user_get(struct snd_kcontrol
*kcontrol
,
1071 struct snd_ctl_elem_value
*ucontrol
)
1073 struct user_element
*ue
= kcontrol
->private_data
;
1075 mutex_lock(&ue
->card
->user_ctl_lock
);
1076 memcpy(&ucontrol
->value
, ue
->elem_data
, ue
->elem_data_size
);
1077 mutex_unlock(&ue
->card
->user_ctl_lock
);
1081 static int snd_ctl_elem_user_put(struct snd_kcontrol
*kcontrol
,
1082 struct snd_ctl_elem_value
*ucontrol
)
1085 struct user_element
*ue
= kcontrol
->private_data
;
1087 mutex_lock(&ue
->card
->user_ctl_lock
);
1088 change
= memcmp(&ucontrol
->value
, ue
->elem_data
, ue
->elem_data_size
) != 0;
1090 memcpy(ue
->elem_data
, &ucontrol
->value
, ue
->elem_data_size
);
1091 mutex_unlock(&ue
->card
->user_ctl_lock
);
1095 static int snd_ctl_elem_user_tlv(struct snd_kcontrol
*kcontrol
,
1098 unsigned int __user
*tlv
)
1100 struct user_element
*ue
= kcontrol
->private_data
;
1105 if (size
> 1024 * 128) /* sane value */
1108 new_data
= memdup_user(tlv
, size
);
1109 if (IS_ERR(new_data
))
1110 return PTR_ERR(new_data
);
1111 mutex_lock(&ue
->card
->user_ctl_lock
);
1112 change
= ue
->tlv_data_size
!= size
;
1114 change
= memcmp(ue
->tlv_data
, new_data
, size
);
1115 kfree(ue
->tlv_data
);
1116 ue
->tlv_data
= new_data
;
1117 ue
->tlv_data_size
= size
;
1118 mutex_unlock(&ue
->card
->user_ctl_lock
);
1122 mutex_lock(&ue
->card
->user_ctl_lock
);
1123 if (!ue
->tlv_data_size
|| !ue
->tlv_data
) {
1127 if (size
< ue
->tlv_data_size
) {
1131 if (copy_to_user(tlv
, ue
->tlv_data
, ue
->tlv_data_size
))
1134 mutex_unlock(&ue
->card
->user_ctl_lock
);
1141 static int snd_ctl_elem_init_enum_names(struct user_element
*ue
)
1144 size_t buf_len
, name_len
;
1146 const uintptr_t user_ptrval
= ue
->info
.value
.enumerated
.names_ptr
;
1148 if (ue
->info
.value
.enumerated
.names_length
> 64 * 1024)
1151 names
= memdup_user((const void __user
*)user_ptrval
,
1152 ue
->info
.value
.enumerated
.names_length
);
1154 return PTR_ERR(names
);
1156 /* check that there are enough valid names */
1157 buf_len
= ue
->info
.value
.enumerated
.names_length
;
1159 for (i
= 0; i
< ue
->info
.value
.enumerated
.items
; ++i
) {
1160 name_len
= strnlen(p
, buf_len
);
1161 if (name_len
== 0 || name_len
>= 64 || name_len
== buf_len
) {
1166 buf_len
-= name_len
+ 1;
1169 ue
->priv_data
= names
;
1170 ue
->info
.value
.enumerated
.names_ptr
= 0;
1175 static void snd_ctl_elem_user_free(struct snd_kcontrol
*kcontrol
)
1177 struct user_element
*ue
= kcontrol
->private_data
;
1179 kfree(ue
->tlv_data
);
1180 kfree(ue
->priv_data
);
1184 static int snd_ctl_elem_add(struct snd_ctl_file
*file
,
1185 struct snd_ctl_elem_info
*info
, int replace
)
1187 /* The capacity of struct snd_ctl_elem_value.value.*/
1188 static const unsigned int value_sizes
[] = {
1189 [SNDRV_CTL_ELEM_TYPE_BOOLEAN
] = sizeof(long),
1190 [SNDRV_CTL_ELEM_TYPE_INTEGER
] = sizeof(long),
1191 [SNDRV_CTL_ELEM_TYPE_ENUMERATED
] = sizeof(unsigned int),
1192 [SNDRV_CTL_ELEM_TYPE_BYTES
] = sizeof(unsigned char),
1193 [SNDRV_CTL_ELEM_TYPE_IEC958
] = sizeof(struct snd_aes_iec958
),
1194 [SNDRV_CTL_ELEM_TYPE_INTEGER64
] = sizeof(long long),
1196 static const unsigned int max_value_counts
[] = {
1197 [SNDRV_CTL_ELEM_TYPE_BOOLEAN
] = 128,
1198 [SNDRV_CTL_ELEM_TYPE_INTEGER
] = 128,
1199 [SNDRV_CTL_ELEM_TYPE_ENUMERATED
] = 128,
1200 [SNDRV_CTL_ELEM_TYPE_BYTES
] = 512,
1201 [SNDRV_CTL_ELEM_TYPE_IEC958
] = 1,
1202 [SNDRV_CTL_ELEM_TYPE_INTEGER64
] = 64,
1204 struct snd_card
*card
= file
->card
;
1205 struct snd_kcontrol
*kctl
;
1207 unsigned int access
;
1209 struct user_element
*ue
;
1212 /* Delete a control to replace them if needed. */
1215 err
= snd_ctl_remove_user_ctl(file
, &info
->id
);
1221 * The number of userspace controls are counted control by control,
1222 * not element by element.
1224 if (card
->user_ctl_count
+ 1 > MAX_USER_CONTROLS
)
1227 /* Check the number of elements for this userspace control. */
1228 count
= info
->owner
;
1232 /* Arrange access permissions if needed. */
1233 access
= info
->access
;
1235 access
= SNDRV_CTL_ELEM_ACCESS_READWRITE
;
1236 access
&= (SNDRV_CTL_ELEM_ACCESS_READWRITE
|
1237 SNDRV_CTL_ELEM_ACCESS_INACTIVE
|
1238 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE
);
1239 if (access
& SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE
)
1240 access
|= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK
;
1241 access
|= SNDRV_CTL_ELEM_ACCESS_USER
;
1244 * Check information and calculate the size of data specific to
1245 * this userspace control.
1247 if (info
->type
< SNDRV_CTL_ELEM_TYPE_BOOLEAN
||
1248 info
->type
> SNDRV_CTL_ELEM_TYPE_INTEGER64
)
1250 if (info
->type
== SNDRV_CTL_ELEM_TYPE_ENUMERATED
&&
1251 info
->value
.enumerated
.items
== 0)
1253 if (info
->count
< 1 ||
1254 info
->count
> max_value_counts
[info
->type
])
1256 private_size
= value_sizes
[info
->type
] * info
->count
;
1259 * Keep memory object for this userspace control. After passing this
1260 * code block, the instance should be freed by snd_ctl_free_one().
1262 * Note that these elements in this control are locked.
1264 err
= snd_ctl_new(&kctl
, count
, access
, file
);
1267 kctl
->private_data
= kzalloc(sizeof(struct user_element
) + private_size
,
1269 if (kctl
->private_data
== NULL
) {
1273 kctl
->private_free
= snd_ctl_elem_user_free
;
1275 /* Set private data for this userspace control. */
1276 ue
= (struct user_element
*)kctl
->private_data
;
1279 ue
->info
.access
= 0;
1280 ue
->elem_data
= (char *)ue
+ sizeof(*ue
);
1281 ue
->elem_data_size
= private_size
;
1282 if (ue
->info
.type
== SNDRV_CTL_ELEM_TYPE_ENUMERATED
) {
1283 err
= snd_ctl_elem_init_enum_names(ue
);
1285 snd_ctl_free_one(kctl
);
1290 /* Set callback functions. */
1291 if (info
->type
== SNDRV_CTL_ELEM_TYPE_ENUMERATED
)
1292 kctl
->info
= snd_ctl_elem_user_enum_info
;
1294 kctl
->info
= snd_ctl_elem_user_info
;
1295 if (access
& SNDRV_CTL_ELEM_ACCESS_READ
)
1296 kctl
->get
= snd_ctl_elem_user_get
;
1297 if (access
& SNDRV_CTL_ELEM_ACCESS_WRITE
)
1298 kctl
->put
= snd_ctl_elem_user_put
;
1299 if (access
& SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE
)
1300 kctl
->tlv
.c
= snd_ctl_elem_user_tlv
;
1302 /* This function manage to free the instance on failure. */
1303 err
= snd_ctl_add(card
, kctl
);
1307 down_write(&card
->controls_rwsem
);
1308 card
->user_ctl_count
++;
1309 up_write(&card
->controls_rwsem
);
1314 static int snd_ctl_elem_add_user(struct snd_ctl_file
*file
,
1315 struct snd_ctl_elem_info __user
*_info
, int replace
)
1317 struct snd_ctl_elem_info info
;
1318 if (copy_from_user(&info
, _info
, sizeof(info
)))
1320 return snd_ctl_elem_add(file
, &info
, replace
);
1323 static int snd_ctl_elem_remove(struct snd_ctl_file
*file
,
1324 struct snd_ctl_elem_id __user
*_id
)
1326 struct snd_ctl_elem_id id
;
1328 if (copy_from_user(&id
, _id
, sizeof(id
)))
1330 return snd_ctl_remove_user_ctl(file
, &id
);
1333 static int snd_ctl_subscribe_events(struct snd_ctl_file
*file
, int __user
*ptr
)
1336 if (get_user(subscribe
, ptr
))
1338 if (subscribe
< 0) {
1339 subscribe
= file
->subscribed
;
1340 if (put_user(subscribe
, ptr
))
1345 file
->subscribed
= 1;
1347 } else if (file
->subscribed
) {
1348 snd_ctl_empty_read_queue(file
);
1349 file
->subscribed
= 0;
1354 static int snd_ctl_tlv_ioctl(struct snd_ctl_file
*file
,
1355 struct snd_ctl_tlv __user
*_tlv
,
1358 struct snd_card
*card
= file
->card
;
1359 struct snd_ctl_tlv tlv
;
1360 struct snd_kcontrol
*kctl
;
1361 struct snd_kcontrol_volatile
*vd
;
1365 if (copy_from_user(&tlv
, _tlv
, sizeof(tlv
)))
1367 if (tlv
.length
< sizeof(unsigned int) * 2)
1369 down_read(&card
->controls_rwsem
);
1370 kctl
= snd_ctl_find_numid(card
, tlv
.numid
);
1375 if (kctl
->tlv
.p
== NULL
) {
1379 vd
= &kctl
->vd
[tlv
.numid
- kctl
->id
.numid
];
1380 if ((op_flag
== 0 && (vd
->access
& SNDRV_CTL_ELEM_ACCESS_TLV_READ
) == 0) ||
1381 (op_flag
> 0 && (vd
->access
& SNDRV_CTL_ELEM_ACCESS_TLV_WRITE
) == 0) ||
1382 (op_flag
< 0 && (vd
->access
& SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND
) == 0)) {
1386 if (vd
->access
& SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK
) {
1387 if (vd
->owner
!= NULL
&& vd
->owner
!= file
) {
1391 err
= kctl
->tlv
.c(kctl
, op_flag
, tlv
.length
, _tlv
->tlv
);
1393 struct snd_ctl_elem_id id
= kctl
->id
;
1394 up_read(&card
->controls_rwsem
);
1395 snd_ctl_notify(card
, SNDRV_CTL_EVENT_MASK_TLV
, &id
);
1403 len
= kctl
->tlv
.p
[1] + 2 * sizeof(unsigned int);
1404 if (tlv
.length
< len
) {
1408 if (copy_to_user(_tlv
->tlv
, kctl
->tlv
.p
, len
))
1412 up_read(&card
->controls_rwsem
);
1416 static long snd_ctl_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1418 struct snd_ctl_file
*ctl
;
1419 struct snd_card
*card
;
1420 struct snd_kctl_ioctl
*p
;
1421 void __user
*argp
= (void __user
*)arg
;
1422 int __user
*ip
= argp
;
1425 ctl
= file
->private_data
;
1427 if (snd_BUG_ON(!card
))
1430 case SNDRV_CTL_IOCTL_PVERSION
:
1431 return put_user(SNDRV_CTL_VERSION
, ip
) ? -EFAULT
: 0;
1432 case SNDRV_CTL_IOCTL_CARD_INFO
:
1433 return snd_ctl_card_info(card
, ctl
, cmd
, argp
);
1434 case SNDRV_CTL_IOCTL_ELEM_LIST
:
1435 return snd_ctl_elem_list(card
, argp
);
1436 case SNDRV_CTL_IOCTL_ELEM_INFO
:
1437 return snd_ctl_elem_info_user(ctl
, argp
);
1438 case SNDRV_CTL_IOCTL_ELEM_READ
:
1439 return snd_ctl_elem_read_user(card
, argp
);
1440 case SNDRV_CTL_IOCTL_ELEM_WRITE
:
1441 return snd_ctl_elem_write_user(ctl
, argp
);
1442 case SNDRV_CTL_IOCTL_ELEM_LOCK
:
1443 return snd_ctl_elem_lock(ctl
, argp
);
1444 case SNDRV_CTL_IOCTL_ELEM_UNLOCK
:
1445 return snd_ctl_elem_unlock(ctl
, argp
);
1446 case SNDRV_CTL_IOCTL_ELEM_ADD
:
1447 return snd_ctl_elem_add_user(ctl
, argp
, 0);
1448 case SNDRV_CTL_IOCTL_ELEM_REPLACE
:
1449 return snd_ctl_elem_add_user(ctl
, argp
, 1);
1450 case SNDRV_CTL_IOCTL_ELEM_REMOVE
:
1451 return snd_ctl_elem_remove(ctl
, argp
);
1452 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS
:
1453 return snd_ctl_subscribe_events(ctl
, ip
);
1454 case SNDRV_CTL_IOCTL_TLV_READ
:
1455 return snd_ctl_tlv_ioctl(ctl
, argp
, SNDRV_CTL_TLV_OP_READ
);
1456 case SNDRV_CTL_IOCTL_TLV_WRITE
:
1457 return snd_ctl_tlv_ioctl(ctl
, argp
, SNDRV_CTL_TLV_OP_WRITE
);
1458 case SNDRV_CTL_IOCTL_TLV_COMMAND
:
1459 return snd_ctl_tlv_ioctl(ctl
, argp
, SNDRV_CTL_TLV_OP_CMD
);
1460 case SNDRV_CTL_IOCTL_POWER
:
1461 return -ENOPROTOOPT
;
1462 case SNDRV_CTL_IOCTL_POWER_STATE
:
1464 return put_user(card
->power_state
, ip
) ? -EFAULT
: 0;
1466 return put_user(SNDRV_CTL_POWER_D0
, ip
) ? -EFAULT
: 0;
1469 down_read(&snd_ioctl_rwsem
);
1470 list_for_each_entry(p
, &snd_control_ioctls
, list
) {
1471 err
= p
->fioctl(card
, ctl
, cmd
, arg
);
1472 if (err
!= -ENOIOCTLCMD
) {
1473 up_read(&snd_ioctl_rwsem
);
1477 up_read(&snd_ioctl_rwsem
);
1478 dev_dbg(card
->dev
, "unknown ioctl = 0x%x\n", cmd
);
1482 static ssize_t
snd_ctl_read(struct file
*file
, char __user
*buffer
,
1483 size_t count
, loff_t
* offset
)
1485 struct snd_ctl_file
*ctl
;
1489 ctl
= file
->private_data
;
1490 if (snd_BUG_ON(!ctl
|| !ctl
->card
))
1492 if (!ctl
->subscribed
)
1494 if (count
< sizeof(struct snd_ctl_event
))
1496 spin_lock_irq(&ctl
->read_lock
);
1497 while (count
>= sizeof(struct snd_ctl_event
)) {
1498 struct snd_ctl_event ev
;
1499 struct snd_kctl_event
*kev
;
1500 while (list_empty(&ctl
->events
)) {
1502 if ((file
->f_flags
& O_NONBLOCK
) != 0 || result
> 0) {
1506 init_waitqueue_entry(&wait
, current
);
1507 add_wait_queue(&ctl
->change_sleep
, &wait
);
1508 set_current_state(TASK_INTERRUPTIBLE
);
1509 spin_unlock_irq(&ctl
->read_lock
);
1511 remove_wait_queue(&ctl
->change_sleep
, &wait
);
1512 if (ctl
->card
->shutdown
)
1514 if (signal_pending(current
))
1515 return -ERESTARTSYS
;
1516 spin_lock_irq(&ctl
->read_lock
);
1518 kev
= snd_kctl_event(ctl
->events
.next
);
1519 ev
.type
= SNDRV_CTL_EVENT_ELEM
;
1520 ev
.data
.elem
.mask
= kev
->mask
;
1521 ev
.data
.elem
.id
= kev
->id
;
1522 list_del(&kev
->list
);
1523 spin_unlock_irq(&ctl
->read_lock
);
1525 if (copy_to_user(buffer
, &ev
, sizeof(struct snd_ctl_event
))) {
1529 spin_lock_irq(&ctl
->read_lock
);
1530 buffer
+= sizeof(struct snd_ctl_event
);
1531 count
-= sizeof(struct snd_ctl_event
);
1532 result
+= sizeof(struct snd_ctl_event
);
1535 spin_unlock_irq(&ctl
->read_lock
);
1537 return result
> 0 ? result
: err
;
1540 static unsigned int snd_ctl_poll(struct file
*file
, poll_table
* wait
)
1543 struct snd_ctl_file
*ctl
;
1545 ctl
= file
->private_data
;
1546 if (!ctl
->subscribed
)
1548 poll_wait(file
, &ctl
->change_sleep
, wait
);
1551 if (!list_empty(&ctl
->events
))
1552 mask
|= POLLIN
| POLLRDNORM
;
1558 * register the device-specific control-ioctls.
1559 * called from each device manager like pcm.c, hwdep.c, etc.
1561 static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn
, struct list_head
*lists
)
1563 struct snd_kctl_ioctl
*pn
;
1565 pn
= kzalloc(sizeof(struct snd_kctl_ioctl
), GFP_KERNEL
);
1569 down_write(&snd_ioctl_rwsem
);
1570 list_add_tail(&pn
->list
, lists
);
1571 up_write(&snd_ioctl_rwsem
);
1576 * snd_ctl_register_ioctl - register the device-specific control-ioctls
1577 * @fcn: ioctl callback function
1579 * called from each device manager like pcm.c, hwdep.c, etc.
1581 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn
)
1583 return _snd_ctl_register_ioctl(fcn
, &snd_control_ioctls
);
1585 EXPORT_SYMBOL(snd_ctl_register_ioctl
);
1587 #ifdef CONFIG_COMPAT
1589 * snd_ctl_register_ioctl_compat - register the device-specific 32bit compat
1591 * @fcn: ioctl callback function
1593 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn
)
1595 return _snd_ctl_register_ioctl(fcn
, &snd_control_compat_ioctls
);
1597 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat
);
1601 * de-register the device-specific control-ioctls.
1603 static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn
,
1604 struct list_head
*lists
)
1606 struct snd_kctl_ioctl
*p
;
1608 if (snd_BUG_ON(!fcn
))
1610 down_write(&snd_ioctl_rwsem
);
1611 list_for_each_entry(p
, lists
, list
) {
1612 if (p
->fioctl
== fcn
) {
1614 up_write(&snd_ioctl_rwsem
);
1619 up_write(&snd_ioctl_rwsem
);
1625 * snd_ctl_unregister_ioctl - de-register the device-specific control-ioctls
1626 * @fcn: ioctl callback function to unregister
1628 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn
)
1630 return _snd_ctl_unregister_ioctl(fcn
, &snd_control_ioctls
);
1632 EXPORT_SYMBOL(snd_ctl_unregister_ioctl
);
1634 #ifdef CONFIG_COMPAT
1636 * snd_ctl_unregister_ioctl - de-register the device-specific compat 32bit
1638 * @fcn: ioctl callback function to unregister
1640 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn
)
1642 return _snd_ctl_unregister_ioctl(fcn
, &snd_control_compat_ioctls
);
1644 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat
);
1647 static int snd_ctl_fasync(int fd
, struct file
* file
, int on
)
1649 struct snd_ctl_file
*ctl
;
1651 ctl
= file
->private_data
;
1652 return fasync_helper(fd
, file
, on
, &ctl
->fasync
);
1655 /* return the preferred subdevice number if already assigned;
1656 * otherwise return -1
1658 int snd_ctl_get_preferred_subdevice(struct snd_card
*card
, int type
)
1660 struct snd_ctl_file
*kctl
;
1663 read_lock(&card
->ctl_files_rwlock
);
1664 list_for_each_entry(kctl
, &card
->ctl_files
, list
) {
1665 if (kctl
->pid
== task_pid(current
)) {
1666 subdevice
= kctl
->preferred_subdevice
[type
];
1667 if (subdevice
!= -1)
1671 read_unlock(&card
->ctl_files_rwlock
);
1674 EXPORT_SYMBOL_GPL(snd_ctl_get_preferred_subdevice
);
1679 #ifdef CONFIG_COMPAT
1680 #include "control_compat.c"
1682 #define snd_ctl_ioctl_compat NULL
1689 static const struct file_operations snd_ctl_f_ops
=
1691 .owner
= THIS_MODULE
,
1692 .read
= snd_ctl_read
,
1693 .open
= snd_ctl_open
,
1694 .release
= snd_ctl_release
,
1695 .llseek
= no_llseek
,
1696 .poll
= snd_ctl_poll
,
1697 .unlocked_ioctl
= snd_ctl_ioctl
,
1698 .compat_ioctl
= snd_ctl_ioctl_compat
,
1699 .fasync
= snd_ctl_fasync
,
1703 * registration of the control device
1705 static int snd_ctl_dev_register(struct snd_device
*device
)
1707 struct snd_card
*card
= device
->device_data
;
1709 return snd_register_device(SNDRV_DEVICE_TYPE_CONTROL
, card
, -1,
1710 &snd_ctl_f_ops
, card
, &card
->ctl_dev
);
1714 * disconnection of the control device
1716 static int snd_ctl_dev_disconnect(struct snd_device
*device
)
1718 struct snd_card
*card
= device
->device_data
;
1719 struct snd_ctl_file
*ctl
;
1721 read_lock(&card
->ctl_files_rwlock
);
1722 list_for_each_entry(ctl
, &card
->ctl_files
, list
) {
1723 wake_up(&ctl
->change_sleep
);
1724 kill_fasync(&ctl
->fasync
, SIGIO
, POLL_ERR
);
1726 read_unlock(&card
->ctl_files_rwlock
);
1728 return snd_unregister_device(&card
->ctl_dev
);
1734 static int snd_ctl_dev_free(struct snd_device
*device
)
1736 struct snd_card
*card
= device
->device_data
;
1737 struct snd_kcontrol
*control
;
1739 down_write(&card
->controls_rwsem
);
1740 while (!list_empty(&card
->controls
)) {
1741 control
= snd_kcontrol(card
->controls
.next
);
1742 snd_ctl_remove(card
, control
);
1744 up_write(&card
->controls_rwsem
);
1745 put_device(&card
->ctl_dev
);
1750 * create control core:
1751 * called from init.c
1753 int snd_ctl_create(struct snd_card
*card
)
1755 static struct snd_device_ops ops
= {
1756 .dev_free
= snd_ctl_dev_free
,
1757 .dev_register
= snd_ctl_dev_register
,
1758 .dev_disconnect
= snd_ctl_dev_disconnect
,
1762 if (snd_BUG_ON(!card
))
1764 if (snd_BUG_ON(card
->number
< 0 || card
->number
>= SNDRV_CARDS
))
1767 snd_device_initialize(&card
->ctl_dev
, card
);
1768 dev_set_name(&card
->ctl_dev
, "controlC%d", card
->number
);
1770 err
= snd_device_new(card
, SNDRV_DEV_CONTROL
, card
, &ops
);
1772 put_device(&card
->ctl_dev
);
1777 * Frequently used control callbacks/helpers
1781 * snd_ctl_boolean_mono_info - Helper function for a standard boolean info
1782 * callback with a mono channel
1783 * @kcontrol: the kcontrol instance
1784 * @uinfo: info to store
1786 * This is a function that can be used as info callback for a standard
1787 * boolean control with a single mono channel.
1789 int snd_ctl_boolean_mono_info(struct snd_kcontrol
*kcontrol
,
1790 struct snd_ctl_elem_info
*uinfo
)
1792 uinfo
->type
= SNDRV_CTL_ELEM_TYPE_BOOLEAN
;
1794 uinfo
->value
.integer
.min
= 0;
1795 uinfo
->value
.integer
.max
= 1;
1798 EXPORT_SYMBOL(snd_ctl_boolean_mono_info
);
1801 * snd_ctl_boolean_stereo_info - Helper function for a standard boolean info
1802 * callback with stereo two channels
1803 * @kcontrol: the kcontrol instance
1804 * @uinfo: info to store
1806 * This is a function that can be used as info callback for a standard
1807 * boolean control with stereo two channels.
1809 int snd_ctl_boolean_stereo_info(struct snd_kcontrol
*kcontrol
,
1810 struct snd_ctl_elem_info
*uinfo
)
1812 uinfo
->type
= SNDRV_CTL_ELEM_TYPE_BOOLEAN
;
1814 uinfo
->value
.integer
.min
= 0;
1815 uinfo
->value
.integer
.max
= 1;
1818 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info
);
1821 * snd_ctl_enum_info - fills the info structure for an enumerated control
1822 * @info: the structure to be filled
1823 * @channels: the number of the control's channels; often one
1824 * @items: the number of control values; also the size of @names
1825 * @names: an array containing the names of all control values
1827 * Sets all required fields in @info to their appropriate values.
1828 * If the control's accessibility is not the default (readable and writable),
1829 * the caller has to fill @info->access.
1833 int snd_ctl_enum_info(struct snd_ctl_elem_info
*info
, unsigned int channels
,
1834 unsigned int items
, const char *const names
[])
1836 info
->type
= SNDRV_CTL_ELEM_TYPE_ENUMERATED
;
1837 info
->count
= channels
;
1838 info
->value
.enumerated
.items
= items
;
1841 if (info
->value
.enumerated
.item
>= items
)
1842 info
->value
.enumerated
.item
= items
- 1;
1843 WARN(strlen(names
[info
->value
.enumerated
.item
]) >= sizeof(info
->value
.enumerated
.name
),
1844 "ALSA: too long item name '%s'\n",
1845 names
[info
->value
.enumerated
.item
]);
1846 strlcpy(info
->value
.enumerated
.name
,
1847 names
[info
->value
.enumerated
.item
],
1848 sizeof(info
->value
.enumerated
.name
));
1851 EXPORT_SYMBOL(snd_ctl_enum_info
);