2 * Routines for driver control interface
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <linux/threads.h>
23 #include <linux/interrupt.h>
24 #include <linux/slab.h>
25 #include <linux/vmalloc.h>
26 #include <linux/time.h>
27 #include <sound/core.h>
28 #include <sound/minors.h>
29 #include <sound/info.h>
30 #include <sound/control.h>
32 /* max number of user-defined controls */
33 #define MAX_USER_CONTROLS 32
34 #define MAX_CONTROL_COUNT 1028
36 struct snd_kctl_ioctl {
37 struct list_head list; /* list of all ioctls */
38 snd_kctl_ioctl_func_t fioctl;
41 static DECLARE_RWSEM(snd_ioctl_rwsem);
42 static LIST_HEAD(snd_control_ioctls);
44 static LIST_HEAD(snd_control_compat_ioctls);
47 static int snd_ctl_open(struct inode *inode, struct file *file)
50 struct snd_card *card;
51 struct snd_ctl_file *ctl;
54 err = nonseekable_open(inode, file);
58 card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL);
63 err = snd_card_file_add(card, file);
68 if (!try_module_get(card->module)) {
72 ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
77 INIT_LIST_HEAD(&ctl->events);
78 init_waitqueue_head(&ctl->change_sleep);
79 spin_lock_init(&ctl->read_lock);
81 ctl->prefer_pcm_subdevice = -1;
82 ctl->prefer_rawmidi_subdevice = -1;
83 ctl->pid = get_pid(task_pid(current));
84 file->private_data = ctl;
85 write_lock_irqsave(&card->ctl_files_rwlock, flags);
86 list_add_tail(&ctl->list, &card->ctl_files);
87 write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
91 module_put(card->module);
93 snd_card_file_remove(card, file);
98 static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl)
101 struct snd_kctl_event *cread;
103 spin_lock_irqsave(&ctl->read_lock, flags);
104 while (!list_empty(&ctl->events)) {
105 cread = snd_kctl_event(ctl->events.next);
106 list_del(&cread->list);
109 spin_unlock_irqrestore(&ctl->read_lock, flags);
112 static int snd_ctl_release(struct inode *inode, struct file *file)
115 struct snd_card *card;
116 struct snd_ctl_file *ctl;
117 struct snd_kcontrol *control;
120 ctl = file->private_data;
121 file->private_data = NULL;
123 write_lock_irqsave(&card->ctl_files_rwlock, flags);
124 list_del(&ctl->list);
125 write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
126 down_write(&card->controls_rwsem);
127 list_for_each_entry(control, &card->controls, list)
128 for (idx = 0; idx < control->count; idx++)
129 if (control->vd[idx].owner == ctl)
130 control->vd[idx].owner = NULL;
131 up_write(&card->controls_rwsem);
132 snd_ctl_empty_read_queue(ctl);
135 module_put(card->module);
136 snd_card_file_remove(card, file);
140 void snd_ctl_notify(struct snd_card *card, unsigned int mask,
141 struct snd_ctl_elem_id *id)
144 struct snd_ctl_file *ctl;
145 struct snd_kctl_event *ev;
147 if (snd_BUG_ON(!card || !id))
149 read_lock(&card->ctl_files_rwlock);
150 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
151 card->mixer_oss_change_count++;
153 list_for_each_entry(ctl, &card->ctl_files, list) {
154 if (!ctl->subscribed)
156 spin_lock_irqsave(&ctl->read_lock, flags);
157 list_for_each_entry(ev, &ctl->events, list) {
158 if (ev->id.numid == id->numid) {
163 ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
167 list_add_tail(&ev->list, &ctl->events);
169 snd_printk(KERN_ERR "No memory available to allocate event\n");
172 wake_up(&ctl->change_sleep);
173 spin_unlock_irqrestore(&ctl->read_lock, flags);
174 kill_fasync(&ctl->fasync, SIGIO, POLL_IN);
176 read_unlock(&card->ctl_files_rwlock);
179 EXPORT_SYMBOL(snd_ctl_notify);
182 * snd_ctl_new - create a control instance from the template
183 * @control: the control template
184 * @access: the default control access
186 * Allocates a new struct snd_kcontrol instance and copies the given template
187 * to the new instance. It does not copy volatile data (access).
189 * Returns the pointer of the new instance, or NULL on failure.
191 static struct snd_kcontrol *snd_ctl_new(struct snd_kcontrol *control,
194 struct snd_kcontrol *kctl;
197 if (snd_BUG_ON(!control || !control->count))
200 if (control->count > MAX_CONTROL_COUNT)
203 kctl = kzalloc(sizeof(*kctl) + sizeof(struct snd_kcontrol_volatile) * control->count, GFP_KERNEL);
205 snd_printk(KERN_ERR "Cannot allocate control instance\n");
209 for (idx = 0; idx < kctl->count; idx++)
210 kctl->vd[idx].access = access;
215 * snd_ctl_new1 - create a control instance from the template
216 * @ncontrol: the initialization record
217 * @private_data: the private data to set
219 * Allocates a new struct snd_kcontrol instance and initialize from the given
220 * template. When the access field of ncontrol is 0, it's assumed as
221 * READWRITE access. When the count field is 0, it's assumes as one.
223 * Returns the pointer of the newly generated instance, or NULL on failure.
225 struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
228 struct snd_kcontrol kctl;
231 if (snd_BUG_ON(!ncontrol || !ncontrol->info))
233 memset(&kctl, 0, sizeof(kctl));
234 kctl.id.iface = ncontrol->iface;
235 kctl.id.device = ncontrol->device;
236 kctl.id.subdevice = ncontrol->subdevice;
237 if (ncontrol->name) {
238 strlcpy(kctl.id.name, ncontrol->name, sizeof(kctl.id.name));
239 if (strcmp(ncontrol->name, kctl.id.name) != 0)
240 snd_printk(KERN_WARNING
241 "Control name '%s' truncated to '%s'\n",
242 ncontrol->name, kctl.id.name);
244 kctl.id.index = ncontrol->index;
245 kctl.count = ncontrol->count ? ncontrol->count : 1;
246 access = ncontrol->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
247 (ncontrol->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
248 SNDRV_CTL_ELEM_ACCESS_INACTIVE|
249 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE|
250 SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND|
251 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK));
252 kctl.info = ncontrol->info;
253 kctl.get = ncontrol->get;
254 kctl.put = ncontrol->put;
255 kctl.tlv.p = ncontrol->tlv.p;
256 kctl.private_value = ncontrol->private_value;
257 kctl.private_data = private_data;
258 return snd_ctl_new(&kctl, access);
261 EXPORT_SYMBOL(snd_ctl_new1);
264 * snd_ctl_free_one - release the control instance
265 * @kcontrol: the control instance
267 * Releases the control instance created via snd_ctl_new()
269 * Don't call this after the control was added to the card.
271 void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
274 if (kcontrol->private_free)
275 kcontrol->private_free(kcontrol);
280 EXPORT_SYMBOL(snd_ctl_free_one);
282 static bool snd_ctl_remove_numid_conflict(struct snd_card *card,
285 struct snd_kcontrol *kctl;
287 list_for_each_entry(kctl, &card->controls, list) {
288 if (kctl->id.numid < card->last_numid + 1 + count &&
289 kctl->id.numid + kctl->count > card->last_numid + 1) {
290 card->last_numid = kctl->id.numid + kctl->count - 1;
297 static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
299 unsigned int iter = 100000;
301 while (snd_ctl_remove_numid_conflict(card, count)) {
303 /* this situation is very unlikely */
304 snd_printk(KERN_ERR "unable to allocate new control numid\n");
312 * snd_ctl_add - add the control instance to the card
313 * @card: the card instance
314 * @kcontrol: the control instance to add
316 * Adds the control instance created via snd_ctl_new() or
317 * snd_ctl_new1() to the given card. Assigns also an unique
318 * numid used for fast search.
320 * Returns zero if successful, or a negative error code on failure.
322 * It frees automatically the control which cannot be added.
324 int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
326 struct snd_ctl_elem_id id;
332 if (snd_BUG_ON(!card || !kcontrol->info))
335 down_write(&card->controls_rwsem);
336 if (snd_ctl_find_id(card, &id)) {
337 up_write(&card->controls_rwsem);
338 snd_printd(KERN_ERR "control %i:%i:%i:%s:%i is already present\n",
347 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
348 up_write(&card->controls_rwsem);
352 list_add_tail(&kcontrol->list, &card->controls);
353 card->controls_count += kcontrol->count;
354 kcontrol->id.numid = card->last_numid + 1;
355 card->last_numid += kcontrol->count;
356 up_write(&card->controls_rwsem);
357 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
358 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
362 snd_ctl_free_one(kcontrol);
366 EXPORT_SYMBOL(snd_ctl_add);
369 * snd_ctl_remove - remove the control from the card and release it
370 * @card: the card instance
371 * @kcontrol: the control instance to remove
373 * Removes the control from the card and then releases the instance.
374 * You don't need to call snd_ctl_free_one(). You must be in
375 * the write lock - down_write(&card->controls_rwsem).
377 * Returns 0 if successful, or a negative error code on failure.
379 int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
381 struct snd_ctl_elem_id id;
384 if (snd_BUG_ON(!card || !kcontrol))
386 list_del(&kcontrol->list);
387 card->controls_count -= kcontrol->count;
389 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
390 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
391 snd_ctl_free_one(kcontrol);
395 EXPORT_SYMBOL(snd_ctl_remove);
398 * snd_ctl_remove_id - remove the control of the given id and release it
399 * @card: the card instance
400 * @id: the control id to remove
402 * Finds the control instance with the given id, removes it from the
403 * card list and releases it.
405 * Returns 0 if successful, or a negative error code on failure.
407 int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
409 struct snd_kcontrol *kctl;
412 down_write(&card->controls_rwsem);
413 kctl = snd_ctl_find_id(card, id);
415 up_write(&card->controls_rwsem);
418 ret = snd_ctl_remove(card, kctl);
419 up_write(&card->controls_rwsem);
423 EXPORT_SYMBOL(snd_ctl_remove_id);
426 * snd_ctl_remove_user_ctl - remove and release the unlocked user control
427 * @file: active control handle
428 * @id: the control id to remove
430 * Finds the control instance with the given id, removes it from the
431 * card list and releases it.
433 * Returns 0 if successful, or a negative error code on failure.
435 static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
436 struct snd_ctl_elem_id *id)
438 struct snd_card *card = file->card;
439 struct snd_kcontrol *kctl;
442 down_write(&card->controls_rwsem);
443 kctl = snd_ctl_find_id(card, id);
448 if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
452 for (idx = 0; idx < kctl->count; idx++)
453 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
457 ret = snd_ctl_remove(card, kctl);
460 card->user_ctl_count--;
462 up_write(&card->controls_rwsem);
467 * snd_ctl_activate_id - activate/inactivate the control of the given id
468 * @card: the card instance
469 * @id: the control id to activate/inactivate
470 * @active: non-zero to activate
472 * Finds the control instance with the given id, and activate or
473 * inactivate the control together with notification, if changed.
475 * Returns 0 if unchanged, 1 if changed, or a negative error code on failure.
477 int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
480 struct snd_kcontrol *kctl;
481 struct snd_kcontrol_volatile *vd;
482 unsigned int index_offset;
485 down_write(&card->controls_rwsem);
486 kctl = snd_ctl_find_id(card, id);
491 index_offset = snd_ctl_get_ioff(kctl, &kctl->id);
492 vd = &kctl->vd[index_offset];
495 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE))
497 vd->access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
499 if (vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE)
501 vd->access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE;
505 up_write(&card->controls_rwsem);
507 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, id);
510 EXPORT_SYMBOL_GPL(snd_ctl_activate_id);
513 * snd_ctl_rename_id - replace the id of a control on the card
514 * @card: the card instance
515 * @src_id: the old id
516 * @dst_id: the new id
518 * Finds the control with the old id from the card, and replaces the
519 * id with the new one.
521 * Returns zero if successful, or a negative error code on failure.
523 int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
524 struct snd_ctl_elem_id *dst_id)
526 struct snd_kcontrol *kctl;
528 down_write(&card->controls_rwsem);
529 kctl = snd_ctl_find_id(card, src_id);
531 up_write(&card->controls_rwsem);
535 kctl->id.numid = card->last_numid + 1;
536 card->last_numid += kctl->count;
537 up_write(&card->controls_rwsem);
541 EXPORT_SYMBOL(snd_ctl_rename_id);
544 * snd_ctl_find_numid - find the control instance with the given number-id
545 * @card: the card instance
546 * @numid: the number-id to search
548 * Finds the control instance with the given number-id from the card.
550 * Returns the pointer of the instance if found, or NULL if not.
552 * The caller must down card->controls_rwsem before calling this function
553 * (if the race condition can happen).
555 struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid)
557 struct snd_kcontrol *kctl;
559 if (snd_BUG_ON(!card || !numid))
561 list_for_each_entry(kctl, &card->controls, list) {
562 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
568 EXPORT_SYMBOL(snd_ctl_find_numid);
571 * snd_ctl_find_id - find the control instance with the given id
572 * @card: the card instance
573 * @id: the id to search
575 * Finds the control instance with the given id from the card.
577 * Returns the pointer of the instance if found, or NULL if not.
579 * The caller must down card->controls_rwsem before calling this function
580 * (if the race condition can happen).
582 struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
583 struct snd_ctl_elem_id *id)
585 struct snd_kcontrol *kctl;
587 if (snd_BUG_ON(!card || !id))
590 return snd_ctl_find_numid(card, id->numid);
591 list_for_each_entry(kctl, &card->controls, list) {
592 if (kctl->id.iface != id->iface)
594 if (kctl->id.device != id->device)
596 if (kctl->id.subdevice != id->subdevice)
598 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
600 if (kctl->id.index > id->index)
602 if (kctl->id.index + kctl->count <= id->index)
609 EXPORT_SYMBOL(snd_ctl_find_id);
611 static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
612 unsigned int cmd, void __user *arg)
614 struct snd_ctl_card_info *info;
616 info = kzalloc(sizeof(*info), GFP_KERNEL);
619 down_read(&snd_ioctl_rwsem);
620 info->card = card->number;
621 strlcpy(info->id, card->id, sizeof(info->id));
622 strlcpy(info->driver, card->driver, sizeof(info->driver));
623 strlcpy(info->name, card->shortname, sizeof(info->name));
624 strlcpy(info->longname, card->longname, sizeof(info->longname));
625 strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
626 strlcpy(info->components, card->components, sizeof(info->components));
627 up_read(&snd_ioctl_rwsem);
628 if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
636 static int snd_ctl_elem_list(struct snd_card *card,
637 struct snd_ctl_elem_list __user *_list)
639 struct list_head *plist;
640 struct snd_ctl_elem_list list;
641 struct snd_kcontrol *kctl;
642 struct snd_ctl_elem_id *dst, *id;
643 unsigned int offset, space, first, jidx;
645 if (copy_from_user(&list, _list, sizeof(list)))
647 offset = list.offset;
650 /* try limit maximum space */
654 /* allocate temporary buffer for atomic operation */
655 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
658 down_read(&card->controls_rwsem);
659 list.count = card->controls_count;
660 plist = card->controls.next;
661 while (plist != &card->controls) {
664 kctl = snd_kcontrol(plist);
665 if (offset < kctl->count)
667 offset -= kctl->count;
672 while (space > 0 && plist != &card->controls) {
673 kctl = snd_kcontrol(plist);
674 for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
675 snd_ctl_build_ioff(id, kctl, jidx);
683 up_read(&card->controls_rwsem);
685 copy_to_user(list.pids, dst,
686 list.used * sizeof(struct snd_ctl_elem_id))) {
692 down_read(&card->controls_rwsem);
693 list.count = card->controls_count;
694 up_read(&card->controls_rwsem);
696 if (copy_to_user(_list, &list, sizeof(list)))
701 static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
702 struct snd_ctl_elem_info *info)
704 struct snd_card *card = ctl->card;
705 struct snd_kcontrol *kctl;
706 struct snd_kcontrol_volatile *vd;
707 unsigned int index_offset;
710 down_read(&card->controls_rwsem);
711 kctl = snd_ctl_find_id(card, &info->id);
713 up_read(&card->controls_rwsem);
716 #ifdef CONFIG_SND_DEBUG
719 result = kctl->info(kctl, info);
721 snd_BUG_ON(info->access);
722 index_offset = snd_ctl_get_ioff(kctl, &info->id);
723 vd = &kctl->vd[index_offset];
724 snd_ctl_build_ioff(&info->id, kctl, index_offset);
725 info->access = vd->access;
727 info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
728 if (vd->owner == ctl)
729 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
730 info->owner = pid_vnr(vd->owner->pid);
735 up_read(&card->controls_rwsem);
739 static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
740 struct snd_ctl_elem_info __user *_info)
742 struct snd_ctl_elem_info info;
745 if (copy_from_user(&info, _info, sizeof(info)))
747 snd_power_lock(ctl->card);
748 result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
750 result = snd_ctl_elem_info(ctl, &info);
751 snd_power_unlock(ctl->card);
753 if (copy_to_user(_info, &info, sizeof(info)))
758 static int snd_ctl_elem_read(struct snd_card *card,
759 struct snd_ctl_elem_value *control)
761 struct snd_kcontrol *kctl;
762 struct snd_kcontrol_volatile *vd;
763 unsigned int index_offset;
766 down_read(&card->controls_rwsem);
767 kctl = snd_ctl_find_id(card, &control->id);
771 index_offset = snd_ctl_get_ioff(kctl, &control->id);
772 vd = &kctl->vd[index_offset];
773 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
775 snd_ctl_build_ioff(&control->id, kctl, index_offset);
776 result = kctl->get(kctl, control);
780 up_read(&card->controls_rwsem);
784 static int snd_ctl_elem_read_user(struct snd_card *card,
785 struct snd_ctl_elem_value __user *_control)
787 struct snd_ctl_elem_value *control;
790 control = memdup_user(_control, sizeof(*control));
792 return PTR_ERR(control);
794 snd_power_lock(card);
795 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
797 result = snd_ctl_elem_read(card, control);
798 snd_power_unlock(card);
800 if (copy_to_user(_control, control, sizeof(*control)))
806 static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
807 struct snd_ctl_elem_value *control)
809 struct snd_kcontrol *kctl;
810 struct snd_kcontrol_volatile *vd;
811 unsigned int index_offset;
814 down_read(&card->controls_rwsem);
815 kctl = snd_ctl_find_id(card, &control->id);
819 index_offset = snd_ctl_get_ioff(kctl, &control->id);
820 vd = &kctl->vd[index_offset];
821 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
823 (file && vd->owner && vd->owner != file)) {
826 snd_ctl_build_ioff(&control->id, kctl, index_offset);
827 result = kctl->put(kctl, control);
830 up_read(&card->controls_rwsem);
831 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
836 up_read(&card->controls_rwsem);
840 static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
841 struct snd_ctl_elem_value __user *_control)
843 struct snd_ctl_elem_value *control;
844 struct snd_card *card;
847 control = memdup_user(_control, sizeof(*control));
849 return PTR_ERR(control);
852 snd_power_lock(card);
853 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
855 result = snd_ctl_elem_write(card, file, control);
856 snd_power_unlock(card);
858 if (copy_to_user(_control, control, sizeof(*control)))
864 static int snd_ctl_elem_lock(struct snd_ctl_file *file,
865 struct snd_ctl_elem_id __user *_id)
867 struct snd_card *card = file->card;
868 struct snd_ctl_elem_id id;
869 struct snd_kcontrol *kctl;
870 struct snd_kcontrol_volatile *vd;
873 if (copy_from_user(&id, _id, sizeof(id)))
875 down_write(&card->controls_rwsem);
876 kctl = snd_ctl_find_id(card, &id);
880 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
881 if (vd->owner != NULL)
888 up_write(&card->controls_rwsem);
892 static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
893 struct snd_ctl_elem_id __user *_id)
895 struct snd_card *card = file->card;
896 struct snd_ctl_elem_id id;
897 struct snd_kcontrol *kctl;
898 struct snd_kcontrol_volatile *vd;
901 if (copy_from_user(&id, _id, sizeof(id)))
903 down_write(&card->controls_rwsem);
904 kctl = snd_ctl_find_id(card, &id);
908 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
909 if (vd->owner == NULL)
911 else if (vd->owner != file)
918 up_write(&card->controls_rwsem);
922 struct user_element {
923 struct snd_ctl_elem_info info;
924 void *elem_data; /* element data */
925 unsigned long elem_data_size; /* size of element data in bytes */
926 void *tlv_data; /* TLV data */
927 unsigned long tlv_data_size; /* TLV data size */
928 void *priv_data; /* private data (like strings for enumerated type) */
929 unsigned long priv_data_size; /* size of private data in bytes */
932 static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
933 struct snd_ctl_elem_info *uinfo)
935 struct user_element *ue = kcontrol->private_data;
941 static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
942 struct snd_ctl_elem_value *ucontrol)
944 struct user_element *ue = kcontrol->private_data;
946 memcpy(&ucontrol->value, ue->elem_data, ue->elem_data_size);
950 static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
951 struct snd_ctl_elem_value *ucontrol)
954 struct user_element *ue = kcontrol->private_data;
956 change = memcmp(&ucontrol->value, ue->elem_data, ue->elem_data_size) != 0;
958 memcpy(ue->elem_data, &ucontrol->value, ue->elem_data_size);
962 static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
965 unsigned int __user *tlv)
967 struct user_element *ue = kcontrol->private_data;
972 if (size > 1024 * 128) /* sane value */
975 new_data = memdup_user(tlv, size);
976 if (IS_ERR(new_data))
977 return PTR_ERR(new_data);
978 change = ue->tlv_data_size != size;
980 change = memcmp(ue->tlv_data, new_data, size);
982 ue->tlv_data = new_data;
983 ue->tlv_data_size = size;
985 if (! ue->tlv_data_size || ! ue->tlv_data)
987 if (size < ue->tlv_data_size)
989 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
995 static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
997 struct user_element *ue = kcontrol->private_data;
1003 static int snd_ctl_elem_add(struct snd_ctl_file *file,
1004 struct snd_ctl_elem_info *info, int replace)
1006 struct snd_card *card = file->card;
1007 struct snd_kcontrol kctl, *_kctl;
1008 unsigned int access;
1010 struct user_element *ue;
1013 if (card->user_ctl_count >= MAX_USER_CONTROLS)
1015 if (info->count < 1)
1017 access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
1018 (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
1019 SNDRV_CTL_ELEM_ACCESS_INACTIVE|
1020 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE));
1022 memset(&kctl, 0, sizeof(kctl));
1023 down_write(&card->controls_rwsem);
1024 _kctl = snd_ctl_find_id(card, &info->id);
1028 err = snd_ctl_remove(card, _kctl);
1035 up_write(&card->controls_rwsem);
1038 memcpy(&kctl.id, &info->id, sizeof(info->id));
1039 kctl.count = info->owner ? info->owner : 1;
1040 access |= SNDRV_CTL_ELEM_ACCESS_USER;
1041 kctl.info = snd_ctl_elem_user_info;
1042 if (access & SNDRV_CTL_ELEM_ACCESS_READ)
1043 kctl.get = snd_ctl_elem_user_get;
1044 if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
1045 kctl.put = snd_ctl_elem_user_put;
1046 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
1047 kctl.tlv.c = snd_ctl_elem_user_tlv;
1048 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1050 switch (info->type) {
1051 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
1052 case SNDRV_CTL_ELEM_TYPE_INTEGER:
1053 private_size = sizeof(long);
1054 if (info->count > 128)
1057 case SNDRV_CTL_ELEM_TYPE_INTEGER64:
1058 private_size = sizeof(long long);
1059 if (info->count > 64)
1062 case SNDRV_CTL_ELEM_TYPE_BYTES:
1063 private_size = sizeof(unsigned char);
1064 if (info->count > 512)
1067 case SNDRV_CTL_ELEM_TYPE_IEC958:
1068 private_size = sizeof(struct snd_aes_iec958);
1069 if (info->count != 1)
1075 private_size *= info->count;
1076 ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);
1080 ue->info.access = 0;
1081 ue->elem_data = (char *)ue + sizeof(*ue);
1082 ue->elem_data_size = private_size;
1083 kctl.private_free = snd_ctl_elem_user_free;
1084 _kctl = snd_ctl_new(&kctl, access);
1085 if (_kctl == NULL) {
1089 _kctl->private_data = ue;
1090 for (idx = 0; idx < _kctl->count; idx++)
1091 _kctl->vd[idx].owner = file;
1092 err = snd_ctl_add(card, _kctl);
1096 down_write(&card->controls_rwsem);
1097 card->user_ctl_count++;
1098 up_write(&card->controls_rwsem);
1103 static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1104 struct snd_ctl_elem_info __user *_info, int replace)
1106 struct snd_ctl_elem_info info;
1107 if (copy_from_user(&info, _info, sizeof(info)))
1109 return snd_ctl_elem_add(file, &info, replace);
1112 static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1113 struct snd_ctl_elem_id __user *_id)
1115 struct snd_ctl_elem_id id;
1117 if (copy_from_user(&id, _id, sizeof(id)))
1119 return snd_ctl_remove_user_ctl(file, &id);
1122 static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
1125 if (get_user(subscribe, ptr))
1127 if (subscribe < 0) {
1128 subscribe = file->subscribed;
1129 if (put_user(subscribe, ptr))
1134 file->subscribed = 1;
1136 } else if (file->subscribed) {
1137 snd_ctl_empty_read_queue(file);
1138 file->subscribed = 0;
1143 static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1144 struct snd_ctl_tlv __user *_tlv,
1147 struct snd_card *card = file->card;
1148 struct snd_ctl_tlv tlv;
1149 struct snd_kcontrol *kctl;
1150 struct snd_kcontrol_volatile *vd;
1154 if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1156 if (tlv.length < sizeof(unsigned int) * 2)
1158 down_read(&card->controls_rwsem);
1159 kctl = snd_ctl_find_numid(card, tlv.numid);
1164 if (kctl->tlv.p == NULL) {
1168 vd = &kctl->vd[tlv.numid - kctl->id.numid];
1169 if ((op_flag == 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1170 (op_flag > 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1171 (op_flag < 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
1175 if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
1176 if (vd->owner != NULL && vd->owner != file) {
1180 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv);
1182 up_read(&card->controls_rwsem);
1183 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &kctl->id);
1191 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1192 if (tlv.length < len) {
1196 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1200 up_read(&card->controls_rwsem);
1204 static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1206 struct snd_ctl_file *ctl;
1207 struct snd_card *card;
1208 struct snd_kctl_ioctl *p;
1209 void __user *argp = (void __user *)arg;
1210 int __user *ip = argp;
1213 ctl = file->private_data;
1215 if (snd_BUG_ON(!card))
1218 case SNDRV_CTL_IOCTL_PVERSION:
1219 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1220 case SNDRV_CTL_IOCTL_CARD_INFO:
1221 return snd_ctl_card_info(card, ctl, cmd, argp);
1222 case SNDRV_CTL_IOCTL_ELEM_LIST:
1223 return snd_ctl_elem_list(card, argp);
1224 case SNDRV_CTL_IOCTL_ELEM_INFO:
1225 return snd_ctl_elem_info_user(ctl, argp);
1226 case SNDRV_CTL_IOCTL_ELEM_READ:
1227 return snd_ctl_elem_read_user(card, argp);
1228 case SNDRV_CTL_IOCTL_ELEM_WRITE:
1229 return snd_ctl_elem_write_user(ctl, argp);
1230 case SNDRV_CTL_IOCTL_ELEM_LOCK:
1231 return snd_ctl_elem_lock(ctl, argp);
1232 case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1233 return snd_ctl_elem_unlock(ctl, argp);
1234 case SNDRV_CTL_IOCTL_ELEM_ADD:
1235 return snd_ctl_elem_add_user(ctl, argp, 0);
1236 case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1237 return snd_ctl_elem_add_user(ctl, argp, 1);
1238 case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1239 return snd_ctl_elem_remove(ctl, argp);
1240 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1241 return snd_ctl_subscribe_events(ctl, ip);
1242 case SNDRV_CTL_IOCTL_TLV_READ:
1243 return snd_ctl_tlv_ioctl(ctl, argp, 0);
1244 case SNDRV_CTL_IOCTL_TLV_WRITE:
1245 return snd_ctl_tlv_ioctl(ctl, argp, 1);
1246 case SNDRV_CTL_IOCTL_TLV_COMMAND:
1247 return snd_ctl_tlv_ioctl(ctl, argp, -1);
1248 case SNDRV_CTL_IOCTL_POWER:
1249 return -ENOPROTOOPT;
1250 case SNDRV_CTL_IOCTL_POWER_STATE:
1252 return put_user(card->power_state, ip) ? -EFAULT : 0;
1254 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1257 down_read(&snd_ioctl_rwsem);
1258 list_for_each_entry(p, &snd_control_ioctls, list) {
1259 err = p->fioctl(card, ctl, cmd, arg);
1260 if (err != -ENOIOCTLCMD) {
1261 up_read(&snd_ioctl_rwsem);
1265 up_read(&snd_ioctl_rwsem);
1266 snd_printdd("unknown ioctl = 0x%x\n", cmd);
1270 static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1271 size_t count, loff_t * offset)
1273 struct snd_ctl_file *ctl;
1277 ctl = file->private_data;
1278 if (snd_BUG_ON(!ctl || !ctl->card))
1280 if (!ctl->subscribed)
1282 if (count < sizeof(struct snd_ctl_event))
1284 spin_lock_irq(&ctl->read_lock);
1285 while (count >= sizeof(struct snd_ctl_event)) {
1286 struct snd_ctl_event ev;
1287 struct snd_kctl_event *kev;
1288 while (list_empty(&ctl->events)) {
1290 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1294 init_waitqueue_entry(&wait, current);
1295 add_wait_queue(&ctl->change_sleep, &wait);
1296 set_current_state(TASK_INTERRUPTIBLE);
1297 spin_unlock_irq(&ctl->read_lock);
1299 remove_wait_queue(&ctl->change_sleep, &wait);
1300 if (signal_pending(current))
1301 return -ERESTARTSYS;
1302 spin_lock_irq(&ctl->read_lock);
1304 kev = snd_kctl_event(ctl->events.next);
1305 ev.type = SNDRV_CTL_EVENT_ELEM;
1306 ev.data.elem.mask = kev->mask;
1307 ev.data.elem.id = kev->id;
1308 list_del(&kev->list);
1309 spin_unlock_irq(&ctl->read_lock);
1311 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
1315 spin_lock_irq(&ctl->read_lock);
1316 buffer += sizeof(struct snd_ctl_event);
1317 count -= sizeof(struct snd_ctl_event);
1318 result += sizeof(struct snd_ctl_event);
1321 spin_unlock_irq(&ctl->read_lock);
1323 return result > 0 ? result : err;
1326 static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1329 struct snd_ctl_file *ctl;
1331 ctl = file->private_data;
1332 if (!ctl->subscribed)
1334 poll_wait(file, &ctl->change_sleep, wait);
1337 if (!list_empty(&ctl->events))
1338 mask |= POLLIN | POLLRDNORM;
1344 * register the device-specific control-ioctls.
1345 * called from each device manager like pcm.c, hwdep.c, etc.
1347 static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1349 struct snd_kctl_ioctl *pn;
1351 pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
1355 down_write(&snd_ioctl_rwsem);
1356 list_add_tail(&pn->list, lists);
1357 up_write(&snd_ioctl_rwsem);
1361 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1363 return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1366 EXPORT_SYMBOL(snd_ctl_register_ioctl);
1368 #ifdef CONFIG_COMPAT
1369 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1371 return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1374 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
1378 * de-register the device-specific control-ioctls.
1380 static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1381 struct list_head *lists)
1383 struct snd_kctl_ioctl *p;
1385 if (snd_BUG_ON(!fcn))
1387 down_write(&snd_ioctl_rwsem);
1388 list_for_each_entry(p, lists, list) {
1389 if (p->fioctl == fcn) {
1391 up_write(&snd_ioctl_rwsem);
1396 up_write(&snd_ioctl_rwsem);
1401 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1403 return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1406 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1408 #ifdef CONFIG_COMPAT
1409 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1411 return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1414 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
1417 static int snd_ctl_fasync(int fd, struct file * file, int on)
1419 struct snd_ctl_file *ctl;
1421 ctl = file->private_data;
1422 return fasync_helper(fd, file, on, &ctl->fasync);
1428 #ifdef CONFIG_COMPAT
1429 #include "control_compat.c"
1431 #define snd_ctl_ioctl_compat NULL
1438 static const struct file_operations snd_ctl_f_ops =
1440 .owner = THIS_MODULE,
1441 .read = snd_ctl_read,
1442 .open = snd_ctl_open,
1443 .release = snd_ctl_release,
1444 .llseek = no_llseek,
1445 .poll = snd_ctl_poll,
1446 .unlocked_ioctl = snd_ctl_ioctl,
1447 .compat_ioctl = snd_ctl_ioctl_compat,
1448 .fasync = snd_ctl_fasync,
1452 * registration of the control device
1454 static int snd_ctl_dev_register(struct snd_device *device)
1456 struct snd_card *card = device->device_data;
1460 if (snd_BUG_ON(!card))
1462 cardnum = card->number;
1463 if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1465 sprintf(name, "controlC%i", cardnum);
1466 if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1467 &snd_ctl_f_ops, card, name)) < 0)
1473 * disconnection of the control device
1475 static int snd_ctl_dev_disconnect(struct snd_device *device)
1477 struct snd_card *card = device->device_data;
1478 struct snd_ctl_file *ctl;
1481 if (snd_BUG_ON(!card))
1483 cardnum = card->number;
1484 if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1487 read_lock(&card->ctl_files_rwlock);
1488 list_for_each_entry(ctl, &card->ctl_files, list) {
1489 wake_up(&ctl->change_sleep);
1490 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1492 read_unlock(&card->ctl_files_rwlock);
1494 if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
1503 static int snd_ctl_dev_free(struct snd_device *device)
1505 struct snd_card *card = device->device_data;
1506 struct snd_kcontrol *control;
1508 down_write(&card->controls_rwsem);
1509 while (!list_empty(&card->controls)) {
1510 control = snd_kcontrol(card->controls.next);
1511 snd_ctl_remove(card, control);
1513 up_write(&card->controls_rwsem);
1518 * create control core:
1519 * called from init.c
1521 int snd_ctl_create(struct snd_card *card)
1523 static struct snd_device_ops ops = {
1524 .dev_free = snd_ctl_dev_free,
1525 .dev_register = snd_ctl_dev_register,
1526 .dev_disconnect = snd_ctl_dev_disconnect,
1529 if (snd_BUG_ON(!card))
1531 return snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1535 * Frequently used control callbacks/helpers
1537 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1538 struct snd_ctl_elem_info *uinfo)
1540 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1542 uinfo->value.integer.min = 0;
1543 uinfo->value.integer.max = 1;
1547 EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1549 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1550 struct snd_ctl_elem_info *uinfo)
1552 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1554 uinfo->value.integer.min = 0;
1555 uinfo->value.integer.max = 1;
1559 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);
1562 * snd_ctl_enum_info - fills the info structure for an enumerated control
1563 * @info: the structure to be filled
1564 * @channels: the number of the control's channels; often one
1565 * @items: the number of control values; also the size of @names
1566 * @names: an array containing the names of all control values
1568 * Sets all required fields in @info to their appropriate values.
1569 * If the control's accessibility is not the default (readable and writable),
1570 * the caller has to fill @info->access.
1572 int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
1573 unsigned int items, const char *const names[])
1575 info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
1576 info->count = channels;
1577 info->value.enumerated.items = items;
1578 if (info->value.enumerated.item >= items)
1579 info->value.enumerated.item = items - 1;
1580 strlcpy(info->value.enumerated.name,
1581 names[info->value.enumerated.item],
1582 sizeof(info->value.enumerated.name));
1585 EXPORT_SYMBOL(snd_ctl_enum_info);