control: remove snd_konctrol_volatile::owner_pid field
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / sound / core / control.c
blob814d2cf1a34cab0649750acaaecb47e80e7e688e
1 /*
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
35 struct snd_kctl_ioctl {
36 struct list_head list; /* list of all ioctls */
37 snd_kctl_ioctl_func_t fioctl;
40 static DECLARE_RWSEM(snd_ioctl_rwsem);
41 static LIST_HEAD(snd_control_ioctls);
42 #ifdef CONFIG_COMPAT
43 static LIST_HEAD(snd_control_compat_ioctls);
44 #endif
46 static int snd_ctl_open(struct inode *inode, struct file *file)
48 unsigned long flags;
49 struct snd_card *card;
50 struct snd_ctl_file *ctl;
51 int err;
53 card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL);
54 if (!card) {
55 err = -ENODEV;
56 goto __error1;
58 err = snd_card_file_add(card, file);
59 if (err < 0) {
60 err = -ENODEV;
61 goto __error1;
63 if (!try_module_get(card->module)) {
64 err = -EFAULT;
65 goto __error2;
67 ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
68 if (ctl == NULL) {
69 err = -ENOMEM;
70 goto __error;
72 INIT_LIST_HEAD(&ctl->events);
73 init_waitqueue_head(&ctl->change_sleep);
74 spin_lock_init(&ctl->read_lock);
75 ctl->card = card;
76 ctl->prefer_pcm_subdevice = -1;
77 ctl->prefer_rawmidi_subdevice = -1;
78 ctl->pid = current->pid;
79 file->private_data = ctl;
80 write_lock_irqsave(&card->ctl_files_rwlock, flags);
81 list_add_tail(&ctl->list, &card->ctl_files);
82 write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
83 return 0;
85 __error:
86 module_put(card->module);
87 __error2:
88 snd_card_file_remove(card, file);
89 __error1:
90 return err;
93 static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl)
95 unsigned long flags;
96 struct snd_kctl_event *cread;
98 spin_lock_irqsave(&ctl->read_lock, flags);
99 while (!list_empty(&ctl->events)) {
100 cread = snd_kctl_event(ctl->events.next);
101 list_del(&cread->list);
102 kfree(cread);
104 spin_unlock_irqrestore(&ctl->read_lock, flags);
107 static int snd_ctl_release(struct inode *inode, struct file *file)
109 unsigned long flags;
110 struct snd_card *card;
111 struct snd_ctl_file *ctl;
112 struct snd_kcontrol *control;
113 unsigned int idx;
115 ctl = file->private_data;
116 file->private_data = NULL;
117 card = ctl->card;
118 write_lock_irqsave(&card->ctl_files_rwlock, flags);
119 list_del(&ctl->list);
120 write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
121 down_write(&card->controls_rwsem);
122 list_for_each_entry(control, &card->controls, list)
123 for (idx = 0; idx < control->count; idx++)
124 if (control->vd[idx].owner == ctl)
125 control->vd[idx].owner = NULL;
126 up_write(&card->controls_rwsem);
127 snd_ctl_empty_read_queue(ctl);
128 kfree(ctl);
129 module_put(card->module);
130 snd_card_file_remove(card, file);
131 return 0;
134 void snd_ctl_notify(struct snd_card *card, unsigned int mask,
135 struct snd_ctl_elem_id *id)
137 unsigned long flags;
138 struct snd_ctl_file *ctl;
139 struct snd_kctl_event *ev;
141 if (snd_BUG_ON(!card || !id))
142 return;
143 read_lock(&card->ctl_files_rwlock);
144 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
145 card->mixer_oss_change_count++;
146 #endif
147 list_for_each_entry(ctl, &card->ctl_files, list) {
148 if (!ctl->subscribed)
149 continue;
150 spin_lock_irqsave(&ctl->read_lock, flags);
151 list_for_each_entry(ev, &ctl->events, list) {
152 if (ev->id.numid == id->numid) {
153 ev->mask |= mask;
154 goto _found;
157 ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
158 if (ev) {
159 ev->id = *id;
160 ev->mask = mask;
161 list_add_tail(&ev->list, &ctl->events);
162 } else {
163 snd_printk(KERN_ERR "No memory available to allocate event\n");
165 _found:
166 wake_up(&ctl->change_sleep);
167 spin_unlock_irqrestore(&ctl->read_lock, flags);
168 kill_fasync(&ctl->fasync, SIGIO, POLL_IN);
170 read_unlock(&card->ctl_files_rwlock);
173 EXPORT_SYMBOL(snd_ctl_notify);
176 * snd_ctl_new - create a control instance from the template
177 * @control: the control template
178 * @access: the default control access
180 * Allocates a new struct snd_kcontrol instance and copies the given template
181 * to the new instance. It does not copy volatile data (access).
183 * Returns the pointer of the new instance, or NULL on failure.
185 static struct snd_kcontrol *snd_ctl_new(struct snd_kcontrol *control,
186 unsigned int access)
188 struct snd_kcontrol *kctl;
189 unsigned int idx;
191 if (snd_BUG_ON(!control || !control->count))
192 return NULL;
193 kctl = kzalloc(sizeof(*kctl) + sizeof(struct snd_kcontrol_volatile) * control->count, GFP_KERNEL);
194 if (kctl == NULL) {
195 snd_printk(KERN_ERR "Cannot allocate control instance\n");
196 return NULL;
198 *kctl = *control;
199 for (idx = 0; idx < kctl->count; idx++)
200 kctl->vd[idx].access = access;
201 return kctl;
205 * snd_ctl_new1 - create a control instance from the template
206 * @ncontrol: the initialization record
207 * @private_data: the private data to set
209 * Allocates a new struct snd_kcontrol instance and initialize from the given
210 * template. When the access field of ncontrol is 0, it's assumed as
211 * READWRITE access. When the count field is 0, it's assumes as one.
213 * Returns the pointer of the newly generated instance, or NULL on failure.
215 struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
216 void *private_data)
218 struct snd_kcontrol kctl;
219 unsigned int access;
221 if (snd_BUG_ON(!ncontrol || !ncontrol->info))
222 return NULL;
223 memset(&kctl, 0, sizeof(kctl));
224 kctl.id.iface = ncontrol->iface;
225 kctl.id.device = ncontrol->device;
226 kctl.id.subdevice = ncontrol->subdevice;
227 if (ncontrol->name) {
228 strlcpy(kctl.id.name, ncontrol->name, sizeof(kctl.id.name));
229 if (strcmp(ncontrol->name, kctl.id.name) != 0)
230 snd_printk(KERN_WARNING
231 "Control name '%s' truncated to '%s'\n",
232 ncontrol->name, kctl.id.name);
234 kctl.id.index = ncontrol->index;
235 kctl.count = ncontrol->count ? ncontrol->count : 1;
236 access = ncontrol->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
237 (ncontrol->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
238 SNDRV_CTL_ELEM_ACCESS_INACTIVE|
239 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE|
240 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK));
241 kctl.info = ncontrol->info;
242 kctl.get = ncontrol->get;
243 kctl.put = ncontrol->put;
244 kctl.tlv.p = ncontrol->tlv.p;
245 kctl.private_value = ncontrol->private_value;
246 kctl.private_data = private_data;
247 return snd_ctl_new(&kctl, access);
250 EXPORT_SYMBOL(snd_ctl_new1);
253 * snd_ctl_free_one - release the control instance
254 * @kcontrol: the control instance
256 * Releases the control instance created via snd_ctl_new()
257 * or snd_ctl_new1().
258 * Don't call this after the control was added to the card.
260 void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
262 if (kcontrol) {
263 if (kcontrol->private_free)
264 kcontrol->private_free(kcontrol);
265 kfree(kcontrol);
269 EXPORT_SYMBOL(snd_ctl_free_one);
271 static unsigned int snd_ctl_hole_check(struct snd_card *card,
272 unsigned int count)
274 struct snd_kcontrol *kctl;
276 list_for_each_entry(kctl, &card->controls, list) {
277 if ((kctl->id.numid <= card->last_numid &&
278 kctl->id.numid + kctl->count > card->last_numid) ||
279 (kctl->id.numid <= card->last_numid + count - 1 &&
280 kctl->id.numid + kctl->count > card->last_numid + count - 1))
281 return card->last_numid = kctl->id.numid + kctl->count - 1;
283 return card->last_numid;
286 static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
288 unsigned int last_numid, iter = 100000;
290 last_numid = card->last_numid;
291 while (last_numid != snd_ctl_hole_check(card, count)) {
292 if (--iter == 0) {
293 /* this situation is very unlikely */
294 snd_printk(KERN_ERR "unable to allocate new control numid\n");
295 return -ENOMEM;
297 last_numid = card->last_numid;
299 return 0;
303 * snd_ctl_add - add the control instance to the card
304 * @card: the card instance
305 * @kcontrol: the control instance to add
307 * Adds the control instance created via snd_ctl_new() or
308 * snd_ctl_new1() to the given card. Assigns also an unique
309 * numid used for fast search.
311 * Returns zero if successful, or a negative error code on failure.
313 * It frees automatically the control which cannot be added.
315 int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
317 struct snd_ctl_elem_id id;
318 unsigned int idx;
319 int err = -EINVAL;
321 if (! kcontrol)
322 return err;
323 if (snd_BUG_ON(!card || !kcontrol->info))
324 goto error;
325 id = kcontrol->id;
326 down_write(&card->controls_rwsem);
327 if (snd_ctl_find_id(card, &id)) {
328 up_write(&card->controls_rwsem);
329 snd_printd(KERN_ERR "control %i:%i:%i:%s:%i is already present\n",
330 id.iface,
331 id.device,
332 id.subdevice,
333 id.name,
334 id.index);
335 err = -EBUSY;
336 goto error;
338 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
339 up_write(&card->controls_rwsem);
340 err = -ENOMEM;
341 goto error;
343 list_add_tail(&kcontrol->list, &card->controls);
344 card->controls_count += kcontrol->count;
345 kcontrol->id.numid = card->last_numid + 1;
346 card->last_numid += kcontrol->count;
347 up_write(&card->controls_rwsem);
348 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
349 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
350 return 0;
352 error:
353 snd_ctl_free_one(kcontrol);
354 return err;
357 EXPORT_SYMBOL(snd_ctl_add);
360 * snd_ctl_remove - remove the control from the card and release it
361 * @card: the card instance
362 * @kcontrol: the control instance to remove
364 * Removes the control from the card and then releases the instance.
365 * You don't need to call snd_ctl_free_one(). You must be in
366 * the write lock - down_write(&card->controls_rwsem).
368 * Returns 0 if successful, or a negative error code on failure.
370 int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
372 struct snd_ctl_elem_id id;
373 unsigned int idx;
375 if (snd_BUG_ON(!card || !kcontrol))
376 return -EINVAL;
377 list_del(&kcontrol->list);
378 card->controls_count -= kcontrol->count;
379 id = kcontrol->id;
380 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
381 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
382 snd_ctl_free_one(kcontrol);
383 return 0;
386 EXPORT_SYMBOL(snd_ctl_remove);
389 * snd_ctl_remove_id - remove the control of the given id and release it
390 * @card: the card instance
391 * @id: the control id to remove
393 * Finds the control instance with the given id, removes it from the
394 * card list and releases it.
396 * Returns 0 if successful, or a negative error code on failure.
398 int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
400 struct snd_kcontrol *kctl;
401 int ret;
403 down_write(&card->controls_rwsem);
404 kctl = snd_ctl_find_id(card, id);
405 if (kctl == NULL) {
406 up_write(&card->controls_rwsem);
407 return -ENOENT;
409 ret = snd_ctl_remove(card, kctl);
410 up_write(&card->controls_rwsem);
411 return ret;
414 EXPORT_SYMBOL(snd_ctl_remove_id);
417 * snd_ctl_remove_user_ctl - remove and release the unlocked user control
418 * @file: active control handle
419 * @id: the control id to remove
421 * Finds the control instance with the given id, removes it from the
422 * card list and releases it.
424 * Returns 0 if successful, or a negative error code on failure.
426 static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
427 struct snd_ctl_elem_id *id)
429 struct snd_card *card = file->card;
430 struct snd_kcontrol *kctl;
431 int idx, ret;
433 down_write(&card->controls_rwsem);
434 kctl = snd_ctl_find_id(card, id);
435 if (kctl == NULL) {
436 ret = -ENOENT;
437 goto error;
439 if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
440 ret = -EINVAL;
441 goto error;
443 for (idx = 0; idx < kctl->count; idx++)
444 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
445 ret = -EBUSY;
446 goto error;
448 ret = snd_ctl_remove(card, kctl);
449 if (ret < 0)
450 goto error;
451 card->user_ctl_count--;
452 error:
453 up_write(&card->controls_rwsem);
454 return ret;
458 * snd_ctl_rename_id - replace the id of a control on the card
459 * @card: the card instance
460 * @src_id: the old id
461 * @dst_id: the new id
463 * Finds the control with the old id from the card, and replaces the
464 * id with the new one.
466 * Returns zero if successful, or a negative error code on failure.
468 int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
469 struct snd_ctl_elem_id *dst_id)
471 struct snd_kcontrol *kctl;
473 down_write(&card->controls_rwsem);
474 kctl = snd_ctl_find_id(card, src_id);
475 if (kctl == NULL) {
476 up_write(&card->controls_rwsem);
477 return -ENOENT;
479 kctl->id = *dst_id;
480 kctl->id.numid = card->last_numid + 1;
481 card->last_numid += kctl->count;
482 up_write(&card->controls_rwsem);
483 return 0;
486 EXPORT_SYMBOL(snd_ctl_rename_id);
489 * snd_ctl_find_numid - find the control instance with the given number-id
490 * @card: the card instance
491 * @numid: the number-id to search
493 * Finds the control instance with the given number-id from the card.
495 * Returns the pointer of the instance if found, or NULL if not.
497 * The caller must down card->controls_rwsem before calling this function
498 * (if the race condition can happen).
500 struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid)
502 struct snd_kcontrol *kctl;
504 if (snd_BUG_ON(!card || !numid))
505 return NULL;
506 list_for_each_entry(kctl, &card->controls, list) {
507 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
508 return kctl;
510 return NULL;
513 EXPORT_SYMBOL(snd_ctl_find_numid);
516 * snd_ctl_find_id - find the control instance with the given id
517 * @card: the card instance
518 * @id: the id to search
520 * Finds the control instance with the given id from the card.
522 * Returns the pointer of the instance if found, or NULL if not.
524 * The caller must down card->controls_rwsem before calling this function
525 * (if the race condition can happen).
527 struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
528 struct snd_ctl_elem_id *id)
530 struct snd_kcontrol *kctl;
532 if (snd_BUG_ON(!card || !id))
533 return NULL;
534 if (id->numid != 0)
535 return snd_ctl_find_numid(card, id->numid);
536 list_for_each_entry(kctl, &card->controls, list) {
537 if (kctl->id.iface != id->iface)
538 continue;
539 if (kctl->id.device != id->device)
540 continue;
541 if (kctl->id.subdevice != id->subdevice)
542 continue;
543 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
544 continue;
545 if (kctl->id.index > id->index)
546 continue;
547 if (kctl->id.index + kctl->count <= id->index)
548 continue;
549 return kctl;
551 return NULL;
554 EXPORT_SYMBOL(snd_ctl_find_id);
556 static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
557 unsigned int cmd, void __user *arg)
559 struct snd_ctl_card_info *info;
561 info = kzalloc(sizeof(*info), GFP_KERNEL);
562 if (! info)
563 return -ENOMEM;
564 down_read(&snd_ioctl_rwsem);
565 info->card = card->number;
566 strlcpy(info->id, card->id, sizeof(info->id));
567 strlcpy(info->driver, card->driver, sizeof(info->driver));
568 strlcpy(info->name, card->shortname, sizeof(info->name));
569 strlcpy(info->longname, card->longname, sizeof(info->longname));
570 strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
571 strlcpy(info->components, card->components, sizeof(info->components));
572 up_read(&snd_ioctl_rwsem);
573 if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
574 kfree(info);
575 return -EFAULT;
577 kfree(info);
578 return 0;
581 static int snd_ctl_elem_list(struct snd_card *card,
582 struct snd_ctl_elem_list __user *_list)
584 struct list_head *plist;
585 struct snd_ctl_elem_list list;
586 struct snd_kcontrol *kctl;
587 struct snd_ctl_elem_id *dst, *id;
588 unsigned int offset, space, first, jidx;
590 if (copy_from_user(&list, _list, sizeof(list)))
591 return -EFAULT;
592 offset = list.offset;
593 space = list.space;
594 first = 0;
595 /* try limit maximum space */
596 if (space > 16384)
597 return -ENOMEM;
598 if (space > 0) {
599 /* allocate temporary buffer for atomic operation */
600 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
601 if (dst == NULL)
602 return -ENOMEM;
603 down_read(&card->controls_rwsem);
604 list.count = card->controls_count;
605 plist = card->controls.next;
606 while (plist != &card->controls) {
607 if (offset == 0)
608 break;
609 kctl = snd_kcontrol(plist);
610 if (offset < kctl->count)
611 break;
612 offset -= kctl->count;
613 plist = plist->next;
615 list.used = 0;
616 id = dst;
617 while (space > 0 && plist != &card->controls) {
618 kctl = snd_kcontrol(plist);
619 for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
620 snd_ctl_build_ioff(id, kctl, jidx);
621 id++;
622 space--;
623 list.used++;
625 plist = plist->next;
626 offset = 0;
628 up_read(&card->controls_rwsem);
629 if (list.used > 0 &&
630 copy_to_user(list.pids, dst,
631 list.used * sizeof(struct snd_ctl_elem_id))) {
632 vfree(dst);
633 return -EFAULT;
635 vfree(dst);
636 } else {
637 down_read(&card->controls_rwsem);
638 list.count = card->controls_count;
639 up_read(&card->controls_rwsem);
641 if (copy_to_user(_list, &list, sizeof(list)))
642 return -EFAULT;
643 return 0;
646 static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
647 struct snd_ctl_elem_info *info)
649 struct snd_card *card = ctl->card;
650 struct snd_kcontrol *kctl;
651 struct snd_kcontrol_volatile *vd;
652 unsigned int index_offset;
653 int result;
655 down_read(&card->controls_rwsem);
656 kctl = snd_ctl_find_id(card, &info->id);
657 if (kctl == NULL) {
658 up_read(&card->controls_rwsem);
659 return -ENOENT;
661 #ifdef CONFIG_SND_DEBUG
662 info->access = 0;
663 #endif
664 result = kctl->info(kctl, info);
665 if (result >= 0) {
666 snd_BUG_ON(info->access);
667 index_offset = snd_ctl_get_ioff(kctl, &info->id);
668 vd = &kctl->vd[index_offset];
669 snd_ctl_build_ioff(&info->id, kctl, index_offset);
670 info->access = vd->access;
671 if (vd->owner) {
672 info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
673 if (vd->owner == ctl)
674 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
675 info->owner = vd->owner->pid;
676 } else {
677 info->owner = -1;
680 up_read(&card->controls_rwsem);
681 return result;
684 static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
685 struct snd_ctl_elem_info __user *_info)
687 struct snd_ctl_elem_info info;
688 int result;
690 if (copy_from_user(&info, _info, sizeof(info)))
691 return -EFAULT;
692 snd_power_lock(ctl->card);
693 result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
694 if (result >= 0)
695 result = snd_ctl_elem_info(ctl, &info);
696 snd_power_unlock(ctl->card);
697 if (result >= 0)
698 if (copy_to_user(_info, &info, sizeof(info)))
699 return -EFAULT;
700 return result;
703 static int snd_ctl_elem_read(struct snd_card *card,
704 struct snd_ctl_elem_value *control)
706 struct snd_kcontrol *kctl;
707 struct snd_kcontrol_volatile *vd;
708 unsigned int index_offset;
709 int result;
711 down_read(&card->controls_rwsem);
712 kctl = snd_ctl_find_id(card, &control->id);
713 if (kctl == NULL) {
714 result = -ENOENT;
715 } else {
716 index_offset = snd_ctl_get_ioff(kctl, &control->id);
717 vd = &kctl->vd[index_offset];
718 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
719 kctl->get != NULL) {
720 snd_ctl_build_ioff(&control->id, kctl, index_offset);
721 result = kctl->get(kctl, control);
722 } else
723 result = -EPERM;
725 up_read(&card->controls_rwsem);
726 return result;
729 static int snd_ctl_elem_read_user(struct snd_card *card,
730 struct snd_ctl_elem_value __user *_control)
732 struct snd_ctl_elem_value *control;
733 int result;
735 control = memdup_user(_control, sizeof(*control));
736 if (IS_ERR(control))
737 return PTR_ERR(control);
739 snd_power_lock(card);
740 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
741 if (result >= 0)
742 result = snd_ctl_elem_read(card, control);
743 snd_power_unlock(card);
744 if (result >= 0)
745 if (copy_to_user(_control, control, sizeof(*control)))
746 result = -EFAULT;
747 kfree(control);
748 return result;
751 static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
752 struct snd_ctl_elem_value *control)
754 struct snd_kcontrol *kctl;
755 struct snd_kcontrol_volatile *vd;
756 unsigned int index_offset;
757 int result;
759 down_read(&card->controls_rwsem);
760 kctl = snd_ctl_find_id(card, &control->id);
761 if (kctl == NULL) {
762 result = -ENOENT;
763 } else {
764 index_offset = snd_ctl_get_ioff(kctl, &control->id);
765 vd = &kctl->vd[index_offset];
766 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
767 kctl->put == NULL ||
768 (file && vd->owner && vd->owner != file)) {
769 result = -EPERM;
770 } else {
771 snd_ctl_build_ioff(&control->id, kctl, index_offset);
772 result = kctl->put(kctl, control);
774 if (result > 0) {
775 up_read(&card->controls_rwsem);
776 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
777 &control->id);
778 return 0;
781 up_read(&card->controls_rwsem);
782 return result;
785 static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
786 struct snd_ctl_elem_value __user *_control)
788 struct snd_ctl_elem_value *control;
789 struct snd_card *card;
790 int result;
792 control = memdup_user(_control, sizeof(*control));
793 if (IS_ERR(control))
794 return PTR_ERR(control);
796 card = file->card;
797 snd_power_lock(card);
798 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
799 if (result >= 0)
800 result = snd_ctl_elem_write(card, file, control);
801 snd_power_unlock(card);
802 if (result >= 0)
803 if (copy_to_user(_control, control, sizeof(*control)))
804 result = -EFAULT;
805 kfree(control);
806 return result;
809 static int snd_ctl_elem_lock(struct snd_ctl_file *file,
810 struct snd_ctl_elem_id __user *_id)
812 struct snd_card *card = file->card;
813 struct snd_ctl_elem_id id;
814 struct snd_kcontrol *kctl;
815 struct snd_kcontrol_volatile *vd;
816 int result;
818 if (copy_from_user(&id, _id, sizeof(id)))
819 return -EFAULT;
820 down_write(&card->controls_rwsem);
821 kctl = snd_ctl_find_id(card, &id);
822 if (kctl == NULL) {
823 result = -ENOENT;
824 } else {
825 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
826 if (vd->owner != NULL)
827 result = -EBUSY;
828 else {
829 vd->owner = file;
830 result = 0;
833 up_write(&card->controls_rwsem);
834 return result;
837 static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
838 struct snd_ctl_elem_id __user *_id)
840 struct snd_card *card = file->card;
841 struct snd_ctl_elem_id id;
842 struct snd_kcontrol *kctl;
843 struct snd_kcontrol_volatile *vd;
844 int result;
846 if (copy_from_user(&id, _id, sizeof(id)))
847 return -EFAULT;
848 down_write(&card->controls_rwsem);
849 kctl = snd_ctl_find_id(card, &id);
850 if (kctl == NULL) {
851 result = -ENOENT;
852 } else {
853 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
854 if (vd->owner == NULL)
855 result = -EINVAL;
856 else if (vd->owner != file)
857 result = -EPERM;
858 else {
859 vd->owner = NULL;
860 result = 0;
863 up_write(&card->controls_rwsem);
864 return result;
867 struct user_element {
868 struct snd_ctl_elem_info info;
869 void *elem_data; /* element data */
870 unsigned long elem_data_size; /* size of element data in bytes */
871 void *tlv_data; /* TLV data */
872 unsigned long tlv_data_size; /* TLV data size */
873 void *priv_data; /* private data (like strings for enumerated type) */
874 unsigned long priv_data_size; /* size of private data in bytes */
877 static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
878 struct snd_ctl_elem_info *uinfo)
880 struct user_element *ue = kcontrol->private_data;
882 *uinfo = ue->info;
883 return 0;
886 static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
887 struct snd_ctl_elem_value *ucontrol)
889 struct user_element *ue = kcontrol->private_data;
891 memcpy(&ucontrol->value, ue->elem_data, ue->elem_data_size);
892 return 0;
895 static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
896 struct snd_ctl_elem_value *ucontrol)
898 int change;
899 struct user_element *ue = kcontrol->private_data;
901 change = memcmp(&ucontrol->value, ue->elem_data, ue->elem_data_size) != 0;
902 if (change)
903 memcpy(ue->elem_data, &ucontrol->value, ue->elem_data_size);
904 return change;
907 static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
908 int op_flag,
909 unsigned int size,
910 unsigned int __user *tlv)
912 struct user_element *ue = kcontrol->private_data;
913 int change = 0;
914 void *new_data;
916 if (op_flag > 0) {
917 if (size > 1024 * 128) /* sane value */
918 return -EINVAL;
920 new_data = memdup_user(tlv, size);
921 if (IS_ERR(new_data))
922 return PTR_ERR(new_data);
923 change = ue->tlv_data_size != size;
924 if (!change)
925 change = memcmp(ue->tlv_data, new_data, size);
926 kfree(ue->tlv_data);
927 ue->tlv_data = new_data;
928 ue->tlv_data_size = size;
929 } else {
930 if (! ue->tlv_data_size || ! ue->tlv_data)
931 return -ENXIO;
932 if (size < ue->tlv_data_size)
933 return -ENOSPC;
934 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
935 return -EFAULT;
937 return change;
940 static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
942 struct user_element *ue = kcontrol->private_data;
943 if (ue->tlv_data)
944 kfree(ue->tlv_data);
945 kfree(ue);
948 static int snd_ctl_elem_add(struct snd_ctl_file *file,
949 struct snd_ctl_elem_info *info, int replace)
951 struct snd_card *card = file->card;
952 struct snd_kcontrol kctl, *_kctl;
953 unsigned int access;
954 long private_size;
955 struct user_element *ue;
956 int idx, err;
958 if (card->user_ctl_count >= MAX_USER_CONTROLS)
959 return -ENOMEM;
960 if (info->count < 1)
961 return -EINVAL;
962 access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
963 (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
964 SNDRV_CTL_ELEM_ACCESS_INACTIVE|
965 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE));
966 info->id.numid = 0;
967 memset(&kctl, 0, sizeof(kctl));
968 down_write(&card->controls_rwsem);
969 _kctl = snd_ctl_find_id(card, &info->id);
970 err = 0;
971 if (_kctl) {
972 if (replace)
973 err = snd_ctl_remove(card, _kctl);
974 else
975 err = -EBUSY;
976 } else {
977 if (replace)
978 err = -ENOENT;
980 up_write(&card->controls_rwsem);
981 if (err < 0)
982 return err;
983 memcpy(&kctl.id, &info->id, sizeof(info->id));
984 kctl.count = info->owner ? info->owner : 1;
985 access |= SNDRV_CTL_ELEM_ACCESS_USER;
986 kctl.info = snd_ctl_elem_user_info;
987 if (access & SNDRV_CTL_ELEM_ACCESS_READ)
988 kctl.get = snd_ctl_elem_user_get;
989 if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
990 kctl.put = snd_ctl_elem_user_put;
991 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
992 kctl.tlv.c = snd_ctl_elem_user_tlv;
993 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
995 switch (info->type) {
996 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
997 case SNDRV_CTL_ELEM_TYPE_INTEGER:
998 private_size = sizeof(long);
999 if (info->count > 128)
1000 return -EINVAL;
1001 break;
1002 case SNDRV_CTL_ELEM_TYPE_INTEGER64:
1003 private_size = sizeof(long long);
1004 if (info->count > 64)
1005 return -EINVAL;
1006 break;
1007 case SNDRV_CTL_ELEM_TYPE_BYTES:
1008 private_size = sizeof(unsigned char);
1009 if (info->count > 512)
1010 return -EINVAL;
1011 break;
1012 case SNDRV_CTL_ELEM_TYPE_IEC958:
1013 private_size = sizeof(struct snd_aes_iec958);
1014 if (info->count != 1)
1015 return -EINVAL;
1016 break;
1017 default:
1018 return -EINVAL;
1020 private_size *= info->count;
1021 ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);
1022 if (ue == NULL)
1023 return -ENOMEM;
1024 ue->info = *info;
1025 ue->info.access = 0;
1026 ue->elem_data = (char *)ue + sizeof(*ue);
1027 ue->elem_data_size = private_size;
1028 kctl.private_free = snd_ctl_elem_user_free;
1029 _kctl = snd_ctl_new(&kctl, access);
1030 if (_kctl == NULL) {
1031 kfree(ue);
1032 return -ENOMEM;
1034 _kctl->private_data = ue;
1035 for (idx = 0; idx < _kctl->count; idx++)
1036 _kctl->vd[idx].owner = file;
1037 err = snd_ctl_add(card, _kctl);
1038 if (err < 0)
1039 return err;
1041 down_write(&card->controls_rwsem);
1042 card->user_ctl_count++;
1043 up_write(&card->controls_rwsem);
1045 return 0;
1048 static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1049 struct snd_ctl_elem_info __user *_info, int replace)
1051 struct snd_ctl_elem_info info;
1052 if (copy_from_user(&info, _info, sizeof(info)))
1053 return -EFAULT;
1054 return snd_ctl_elem_add(file, &info, replace);
1057 static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1058 struct snd_ctl_elem_id __user *_id)
1060 struct snd_ctl_elem_id id;
1062 if (copy_from_user(&id, _id, sizeof(id)))
1063 return -EFAULT;
1064 return snd_ctl_remove_user_ctl(file, &id);
1067 static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
1069 int subscribe;
1070 if (get_user(subscribe, ptr))
1071 return -EFAULT;
1072 if (subscribe < 0) {
1073 subscribe = file->subscribed;
1074 if (put_user(subscribe, ptr))
1075 return -EFAULT;
1076 return 0;
1078 if (subscribe) {
1079 file->subscribed = 1;
1080 return 0;
1081 } else if (file->subscribed) {
1082 snd_ctl_empty_read_queue(file);
1083 file->subscribed = 0;
1085 return 0;
1088 static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1089 struct snd_ctl_tlv __user *_tlv,
1090 int op_flag)
1092 struct snd_card *card = file->card;
1093 struct snd_ctl_tlv tlv;
1094 struct snd_kcontrol *kctl;
1095 struct snd_kcontrol_volatile *vd;
1096 unsigned int len;
1097 int err = 0;
1099 if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1100 return -EFAULT;
1101 if (tlv.length < sizeof(unsigned int) * 3)
1102 return -EINVAL;
1103 down_read(&card->controls_rwsem);
1104 kctl = snd_ctl_find_numid(card, tlv.numid);
1105 if (kctl == NULL) {
1106 err = -ENOENT;
1107 goto __kctl_end;
1109 if (kctl->tlv.p == NULL) {
1110 err = -ENXIO;
1111 goto __kctl_end;
1113 vd = &kctl->vd[tlv.numid - kctl->id.numid];
1114 if ((op_flag == 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1115 (op_flag > 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1116 (op_flag < 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
1117 err = -ENXIO;
1118 goto __kctl_end;
1120 if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
1121 if (file && vd->owner != NULL && vd->owner != file) {
1122 err = -EPERM;
1123 goto __kctl_end;
1125 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv);
1126 if (err > 0) {
1127 up_read(&card->controls_rwsem);
1128 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &kctl->id);
1129 return 0;
1131 } else {
1132 if (op_flag) {
1133 err = -ENXIO;
1134 goto __kctl_end;
1136 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1137 if (tlv.length < len) {
1138 err = -ENOMEM;
1139 goto __kctl_end;
1141 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1142 err = -EFAULT;
1144 __kctl_end:
1145 up_read(&card->controls_rwsem);
1146 return err;
1149 static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1151 struct snd_ctl_file *ctl;
1152 struct snd_card *card;
1153 struct snd_kctl_ioctl *p;
1154 void __user *argp = (void __user *)arg;
1155 int __user *ip = argp;
1156 int err;
1158 ctl = file->private_data;
1159 card = ctl->card;
1160 if (snd_BUG_ON(!card))
1161 return -ENXIO;
1162 switch (cmd) {
1163 case SNDRV_CTL_IOCTL_PVERSION:
1164 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1165 case SNDRV_CTL_IOCTL_CARD_INFO:
1166 return snd_ctl_card_info(card, ctl, cmd, argp);
1167 case SNDRV_CTL_IOCTL_ELEM_LIST:
1168 return snd_ctl_elem_list(card, argp);
1169 case SNDRV_CTL_IOCTL_ELEM_INFO:
1170 return snd_ctl_elem_info_user(ctl, argp);
1171 case SNDRV_CTL_IOCTL_ELEM_READ:
1172 return snd_ctl_elem_read_user(card, argp);
1173 case SNDRV_CTL_IOCTL_ELEM_WRITE:
1174 return snd_ctl_elem_write_user(ctl, argp);
1175 case SNDRV_CTL_IOCTL_ELEM_LOCK:
1176 return snd_ctl_elem_lock(ctl, argp);
1177 case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1178 return snd_ctl_elem_unlock(ctl, argp);
1179 case SNDRV_CTL_IOCTL_ELEM_ADD:
1180 return snd_ctl_elem_add_user(ctl, argp, 0);
1181 case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1182 return snd_ctl_elem_add_user(ctl, argp, 1);
1183 case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1184 return snd_ctl_elem_remove(ctl, argp);
1185 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1186 return snd_ctl_subscribe_events(ctl, ip);
1187 case SNDRV_CTL_IOCTL_TLV_READ:
1188 return snd_ctl_tlv_ioctl(ctl, argp, 0);
1189 case SNDRV_CTL_IOCTL_TLV_WRITE:
1190 return snd_ctl_tlv_ioctl(ctl, argp, 1);
1191 case SNDRV_CTL_IOCTL_TLV_COMMAND:
1192 return snd_ctl_tlv_ioctl(ctl, argp, -1);
1193 case SNDRV_CTL_IOCTL_POWER:
1194 return -ENOPROTOOPT;
1195 case SNDRV_CTL_IOCTL_POWER_STATE:
1196 #ifdef CONFIG_PM
1197 return put_user(card->power_state, ip) ? -EFAULT : 0;
1198 #else
1199 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1200 #endif
1202 down_read(&snd_ioctl_rwsem);
1203 list_for_each_entry(p, &snd_control_ioctls, list) {
1204 err = p->fioctl(card, ctl, cmd, arg);
1205 if (err != -ENOIOCTLCMD) {
1206 up_read(&snd_ioctl_rwsem);
1207 return err;
1210 up_read(&snd_ioctl_rwsem);
1211 snd_printdd("unknown ioctl = 0x%x\n", cmd);
1212 return -ENOTTY;
1215 static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1216 size_t count, loff_t * offset)
1218 struct snd_ctl_file *ctl;
1219 int err = 0;
1220 ssize_t result = 0;
1222 ctl = file->private_data;
1223 if (snd_BUG_ON(!ctl || !ctl->card))
1224 return -ENXIO;
1225 if (!ctl->subscribed)
1226 return -EBADFD;
1227 if (count < sizeof(struct snd_ctl_event))
1228 return -EINVAL;
1229 spin_lock_irq(&ctl->read_lock);
1230 while (count >= sizeof(struct snd_ctl_event)) {
1231 struct snd_ctl_event ev;
1232 struct snd_kctl_event *kev;
1233 while (list_empty(&ctl->events)) {
1234 wait_queue_t wait;
1235 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1236 err = -EAGAIN;
1237 goto __end_lock;
1239 init_waitqueue_entry(&wait, current);
1240 add_wait_queue(&ctl->change_sleep, &wait);
1241 set_current_state(TASK_INTERRUPTIBLE);
1242 spin_unlock_irq(&ctl->read_lock);
1243 schedule();
1244 remove_wait_queue(&ctl->change_sleep, &wait);
1245 if (signal_pending(current))
1246 return -ERESTARTSYS;
1247 spin_lock_irq(&ctl->read_lock);
1249 kev = snd_kctl_event(ctl->events.next);
1250 ev.type = SNDRV_CTL_EVENT_ELEM;
1251 ev.data.elem.mask = kev->mask;
1252 ev.data.elem.id = kev->id;
1253 list_del(&kev->list);
1254 spin_unlock_irq(&ctl->read_lock);
1255 kfree(kev);
1256 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
1257 err = -EFAULT;
1258 goto __end;
1260 spin_lock_irq(&ctl->read_lock);
1261 buffer += sizeof(struct snd_ctl_event);
1262 count -= sizeof(struct snd_ctl_event);
1263 result += sizeof(struct snd_ctl_event);
1265 __end_lock:
1266 spin_unlock_irq(&ctl->read_lock);
1267 __end:
1268 return result > 0 ? result : err;
1271 static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1273 unsigned int mask;
1274 struct snd_ctl_file *ctl;
1276 ctl = file->private_data;
1277 if (!ctl->subscribed)
1278 return 0;
1279 poll_wait(file, &ctl->change_sleep, wait);
1281 mask = 0;
1282 if (!list_empty(&ctl->events))
1283 mask |= POLLIN | POLLRDNORM;
1285 return mask;
1289 * register the device-specific control-ioctls.
1290 * called from each device manager like pcm.c, hwdep.c, etc.
1292 static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1294 struct snd_kctl_ioctl *pn;
1296 pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
1297 if (pn == NULL)
1298 return -ENOMEM;
1299 pn->fioctl = fcn;
1300 down_write(&snd_ioctl_rwsem);
1301 list_add_tail(&pn->list, lists);
1302 up_write(&snd_ioctl_rwsem);
1303 return 0;
1306 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1308 return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1311 EXPORT_SYMBOL(snd_ctl_register_ioctl);
1313 #ifdef CONFIG_COMPAT
1314 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1316 return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1319 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
1320 #endif
1323 * de-register the device-specific control-ioctls.
1325 static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1326 struct list_head *lists)
1328 struct snd_kctl_ioctl *p;
1330 if (snd_BUG_ON(!fcn))
1331 return -EINVAL;
1332 down_write(&snd_ioctl_rwsem);
1333 list_for_each_entry(p, lists, list) {
1334 if (p->fioctl == fcn) {
1335 list_del(&p->list);
1336 up_write(&snd_ioctl_rwsem);
1337 kfree(p);
1338 return 0;
1341 up_write(&snd_ioctl_rwsem);
1342 snd_BUG();
1343 return -EINVAL;
1346 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1348 return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1351 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1353 #ifdef CONFIG_COMPAT
1354 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1356 return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1359 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
1360 #endif
1362 static int snd_ctl_fasync(int fd, struct file * file, int on)
1364 struct snd_ctl_file *ctl;
1366 ctl = file->private_data;
1367 return fasync_helper(fd, file, on, &ctl->fasync);
1371 * ioctl32 compat
1373 #ifdef CONFIG_COMPAT
1374 #include "control_compat.c"
1375 #else
1376 #define snd_ctl_ioctl_compat NULL
1377 #endif
1380 * INIT PART
1383 static const struct file_operations snd_ctl_f_ops =
1385 .owner = THIS_MODULE,
1386 .read = snd_ctl_read,
1387 .open = snd_ctl_open,
1388 .release = snd_ctl_release,
1389 .poll = snd_ctl_poll,
1390 .unlocked_ioctl = snd_ctl_ioctl,
1391 .compat_ioctl = snd_ctl_ioctl_compat,
1392 .fasync = snd_ctl_fasync,
1396 * registration of the control device
1398 static int snd_ctl_dev_register(struct snd_device *device)
1400 struct snd_card *card = device->device_data;
1401 int err, cardnum;
1402 char name[16];
1404 if (snd_BUG_ON(!card))
1405 return -ENXIO;
1406 cardnum = card->number;
1407 if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1408 return -ENXIO;
1409 sprintf(name, "controlC%i", cardnum);
1410 if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1411 &snd_ctl_f_ops, card, name)) < 0)
1412 return err;
1413 return 0;
1417 * disconnection of the control device
1419 static int snd_ctl_dev_disconnect(struct snd_device *device)
1421 struct snd_card *card = device->device_data;
1422 struct snd_ctl_file *ctl;
1423 int err, cardnum;
1425 if (snd_BUG_ON(!card))
1426 return -ENXIO;
1427 cardnum = card->number;
1428 if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1429 return -ENXIO;
1431 read_lock(&card->ctl_files_rwlock);
1432 list_for_each_entry(ctl, &card->ctl_files, list) {
1433 wake_up(&ctl->change_sleep);
1434 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1436 read_unlock(&card->ctl_files_rwlock);
1438 if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
1439 card, -1)) < 0)
1440 return err;
1441 return 0;
1445 * free all controls
1447 static int snd_ctl_dev_free(struct snd_device *device)
1449 struct snd_card *card = device->device_data;
1450 struct snd_kcontrol *control;
1452 down_write(&card->controls_rwsem);
1453 while (!list_empty(&card->controls)) {
1454 control = snd_kcontrol(card->controls.next);
1455 snd_ctl_remove(card, control);
1457 up_write(&card->controls_rwsem);
1458 return 0;
1462 * create control core:
1463 * called from init.c
1465 int snd_ctl_create(struct snd_card *card)
1467 static struct snd_device_ops ops = {
1468 .dev_free = snd_ctl_dev_free,
1469 .dev_register = snd_ctl_dev_register,
1470 .dev_disconnect = snd_ctl_dev_disconnect,
1473 if (snd_BUG_ON(!card))
1474 return -ENXIO;
1475 return snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1479 * Frequently used control callbacks
1481 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1482 struct snd_ctl_elem_info *uinfo)
1484 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1485 uinfo->count = 1;
1486 uinfo->value.integer.min = 0;
1487 uinfo->value.integer.max = 1;
1488 return 0;
1491 EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1493 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1494 struct snd_ctl_elem_info *uinfo)
1496 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1497 uinfo->count = 2;
1498 uinfo->value.integer.min = 0;
1499 uinfo->value.integer.max = 1;
1500 return 0;
1503 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);