blob: b9611344ff9e53ec351c420411ceb28f2ddb5b8a [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Routines for driver control interface
Jaroslav Kyselac1017a42007-10-15 09:50:19 +02003 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
5 *
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.
10 *
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.
15 *
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
19 *
20 */
21
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/threads.h>
23#include <linux/interrupt.h>
Paul Gortmakerda155d52011-07-15 12:38:28 -040024#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#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>
32
33/* max number of user-defined controls */
34#define MAX_USER_CONTROLS 32
Dan Rosenberg5591bf02010-09-28 14:18:20 -040035#define MAX_CONTROL_COUNT 1028
Linus Torvalds1da177e2005-04-16 15:20:36 -070036
Takashi Iwai82e9bae2005-11-17 13:53:23 +010037struct snd_kctl_ioctl {
Linus Torvalds1da177e2005-04-16 15:20:36 -070038 struct list_head list; /* list of all ioctls */
39 snd_kctl_ioctl_func_t fioctl;
Takashi Iwai82e9bae2005-11-17 13:53:23 +010040};
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
42static DECLARE_RWSEM(snd_ioctl_rwsem);
43static LIST_HEAD(snd_control_ioctls);
44#ifdef CONFIG_COMPAT
45static LIST_HEAD(snd_control_compat_ioctls);
46#endif
47
48static int snd_ctl_open(struct inode *inode, struct file *file)
49{
Linus Torvalds1da177e2005-04-16 15:20:36 -070050 unsigned long flags;
Takashi Iwai82e9bae2005-11-17 13:53:23 +010051 struct snd_card *card;
52 struct snd_ctl_file *ctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -070053 int err;
54
Takashi Iwai02f48652010-04-13 11:49:04 +020055 err = nonseekable_open(inode, file);
56 if (err < 0)
57 return err;
58
Clemens Ladischf87135f2005-11-20 14:06:59 +010059 card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 if (!card) {
61 err = -ENODEV;
62 goto __error1;
63 }
64 err = snd_card_file_add(card, file);
65 if (err < 0) {
66 err = -ENODEV;
67 goto __error1;
68 }
69 if (!try_module_get(card->module)) {
70 err = -EFAULT;
71 goto __error2;
72 }
Takashi Iwaica2c0962005-09-09 14:20:23 +020073 ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 if (ctl == NULL) {
75 err = -ENOMEM;
76 goto __error;
77 }
78 INIT_LIST_HEAD(&ctl->events);
79 init_waitqueue_head(&ctl->change_sleep);
80 spin_lock_init(&ctl->read_lock);
81 ctl->card = card;
Takashi Iwai2529bba2006-08-04 12:57:19 +020082 ctl->prefer_pcm_subdevice = -1;
83 ctl->prefer_rawmidi_subdevice = -1;
Clemens Ladisch25d27ed2009-11-02 09:35:44 +010084 ctl->pid = get_pid(task_pid(current));
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 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);
Takashi Iwaia0830db2012-10-16 13:05:59 +020089 snd_card_unref(card);
Linus Torvalds1da177e2005-04-16 15:20:36 -070090 return 0;
91
92 __error:
93 module_put(card->module);
94 __error2:
95 snd_card_file_remove(card, file);
96 __error1:
Takashi Iwaia0830db2012-10-16 13:05:59 +020097 if (card)
98 snd_card_unref(card);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 return err;
100}
101
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100102static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103{
Borislav Petkov7507e8d2007-10-22 17:11:09 +0200104 unsigned long flags;
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100105 struct snd_kctl_event *cread;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106
Borislav Petkov7507e8d2007-10-22 17:11:09 +0200107 spin_lock_irqsave(&ctl->read_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 while (!list_empty(&ctl->events)) {
109 cread = snd_kctl_event(ctl->events.next);
110 list_del(&cread->list);
111 kfree(cread);
112 }
Borislav Petkov7507e8d2007-10-22 17:11:09 +0200113 spin_unlock_irqrestore(&ctl->read_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114}
115
116static int snd_ctl_release(struct inode *inode, struct file *file)
117{
118 unsigned long flags;
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100119 struct snd_card *card;
120 struct snd_ctl_file *ctl;
121 struct snd_kcontrol *control;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 unsigned int idx;
123
124 ctl = file->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 file->private_data = NULL;
126 card = ctl->card;
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);
Johannes Berg9244b2c2006-10-05 16:02:22 +0200131 list_for_each_entry(control, &card->controls, list)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 for (idx = 0; idx < control->count; idx++)
133 if (control->vd[idx].owner == ctl)
134 control->vd[idx].owner = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 up_write(&card->controls_rwsem);
136 snd_ctl_empty_read_queue(ctl);
Clemens Ladisch25d27ed2009-11-02 09:35:44 +0100137 put_pid(ctl->pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138 kfree(ctl);
139 module_put(card->module);
140 snd_card_file_remove(card, file);
141 return 0;
142}
143
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100144void snd_ctl_notify(struct snd_card *card, unsigned int mask,
145 struct snd_ctl_elem_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146{
147 unsigned long flags;
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100148 struct snd_ctl_file *ctl;
149 struct snd_kctl_event *ev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200151 if (snd_BUG_ON(!card || !id))
152 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 read_lock(&card->ctl_files_rwlock);
Takashi Iwai8eeaa2f2014-02-10 09:48:47 +0100154#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 card->mixer_oss_change_count++;
156#endif
Johannes Berg9244b2c2006-10-05 16:02:22 +0200157 list_for_each_entry(ctl, &card->ctl_files, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 if (!ctl->subscribed)
159 continue;
160 spin_lock_irqsave(&ctl->read_lock, flags);
Johannes Berg9244b2c2006-10-05 16:02:22 +0200161 list_for_each_entry(ev, &ctl->events, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 if (ev->id.numid == id->numid) {
163 ev->mask |= mask;
164 goto _found;
165 }
166 }
Takashi Iwaica2c0962005-09-09 14:20:23 +0200167 ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 if (ev) {
169 ev->id = *id;
170 ev->mask = mask;
171 list_add_tail(&ev->list, &ctl->events);
172 } else {
Takashi Iwaibb009452014-02-04 18:18:16 +0100173 dev_err(card->dev, "No memory available to allocate event\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 }
175 _found:
176 wake_up(&ctl->change_sleep);
177 spin_unlock_irqrestore(&ctl->read_lock, flags);
178 kill_fasync(&ctl->fasync, SIGIO, POLL_IN);
179 }
180 read_unlock(&card->ctl_files_rwlock);
181}
182
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200183EXPORT_SYMBOL(snd_ctl_notify);
184
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185/**
186 * snd_ctl_new - create a control instance from the template
187 * @control: the control template
188 * @access: the default control access
189 *
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100190 * Allocates a new struct snd_kcontrol instance and copies the given template
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 * to the new instance. It does not copy volatile data (access).
192 *
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100193 * Return: The pointer of the new instance, or %NULL on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 */
Adrian Bunk0b51ba02006-11-20 17:50:17 +0100195static struct snd_kcontrol *snd_ctl_new(struct snd_kcontrol *control,
196 unsigned int access)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100198 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 unsigned int idx;
200
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200201 if (snd_BUG_ON(!control || !control->count))
202 return NULL;
Dan Rosenberg5591bf02010-09-28 14:18:20 -0400203
204 if (control->count > MAX_CONTROL_COUNT)
205 return NULL;
206
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100207 kctl = kzalloc(sizeof(*kctl) + sizeof(struct snd_kcontrol_volatile) * control->count, GFP_KERNEL);
Takashi Iwai73e77ba2005-11-17 17:44:01 +0100208 if (kctl == NULL) {
Takashi Iwaibb009452014-02-04 18:18:16 +0100209 pr_err("ALSA: Cannot allocate control instance\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210 return NULL;
Takashi Iwai73e77ba2005-11-17 17:44:01 +0100211 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 *kctl = *control;
213 for (idx = 0; idx < kctl->count; idx++)
214 kctl->vd[idx].access = access;
215 return kctl;
216}
217
218/**
219 * snd_ctl_new1 - create a control instance from the template
220 * @ncontrol: the initialization record
221 * @private_data: the private data to set
222 *
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100223 * Allocates a new struct snd_kcontrol instance and initialize from the given
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 * template. When the access field of ncontrol is 0, it's assumed as
225 * READWRITE access. When the count field is 0, it's assumes as one.
226 *
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100227 * Return: The pointer of the newly generated instance, or %NULL on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100229struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
230 void *private_data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100232 struct snd_kcontrol kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 unsigned int access;
234
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200235 if (snd_BUG_ON(!ncontrol || !ncontrol->info))
236 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 memset(&kctl, 0, sizeof(kctl));
238 kctl.id.iface = ncontrol->iface;
239 kctl.id.device = ncontrol->device;
240 kctl.id.subdevice = ncontrol->subdevice;
Mark Brown366840d2008-10-29 14:40:30 +0000241 if (ncontrol->name) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 strlcpy(kctl.id.name, ncontrol->name, sizeof(kctl.id.name));
Mark Brown366840d2008-10-29 14:40:30 +0000243 if (strcmp(ncontrol->name, kctl.id.name) != 0)
Takashi Iwaibb009452014-02-04 18:18:16 +0100244 pr_warn("ALSA: Control name '%s' truncated to '%s'\n",
245 ncontrol->name, kctl.id.name);
Mark Brown366840d2008-10-29 14:40:30 +0000246 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 kctl.id.index = ncontrol->index;
248 kctl.count = ncontrol->count ? ncontrol->count : 1;
249 access = ncontrol->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +0200250 (ncontrol->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
Takashi Iwaia8d372f2012-07-30 13:47:07 +0200251 SNDRV_CTL_ELEM_ACCESS_VOLATILE|
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +0200252 SNDRV_CTL_ELEM_ACCESS_INACTIVE|
Clemens Ladischa75d7a42010-02-01 13:29:50 +0100253 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE|
254 SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND|
255 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 kctl.info = ncontrol->info;
257 kctl.get = ncontrol->get;
258 kctl.put = ncontrol->put;
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +0200259 kctl.tlv.p = ncontrol->tlv.p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260 kctl.private_value = ncontrol->private_value;
261 kctl.private_data = private_data;
262 return snd_ctl_new(&kctl, access);
263}
264
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200265EXPORT_SYMBOL(snd_ctl_new1);
266
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267/**
268 * snd_ctl_free_one - release the control instance
269 * @kcontrol: the control instance
270 *
271 * Releases the control instance created via snd_ctl_new()
272 * or snd_ctl_new1().
273 * Don't call this after the control was added to the card.
274 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100275void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276{
277 if (kcontrol) {
278 if (kcontrol->private_free)
279 kcontrol->private_free(kcontrol);
280 kfree(kcontrol);
281 }
282}
283
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200284EXPORT_SYMBOL(snd_ctl_free_one);
285
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100286static bool snd_ctl_remove_numid_conflict(struct snd_card *card,
287 unsigned int count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100289 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290
Lars-Peter Clausenac902c12014-06-18 13:32:34 +0200291 /* Make sure that the ids assigned to the control do not wrap around */
292 if (card->last_numid >= UINT_MAX - count)
293 card->last_numid = 0;
294
Johannes Berg9244b2c2006-10-05 16:02:22 +0200295 list_for_each_entry(kctl, &card->controls, list) {
Clemens Ladisch7c733582011-03-07 13:22:50 +0100296 if (kctl->id.numid < card->last_numid + 1 + count &&
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100297 kctl->id.numid + kctl->count > card->last_numid + 1) {
298 card->last_numid = kctl->id.numid + kctl->count - 1;
299 return true;
300 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 }
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100302 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303}
304
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100305static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306{
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100307 unsigned int iter = 100000;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100309 while (snd_ctl_remove_numid_conflict(card, count)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 if (--iter == 0) {
311 /* this situation is very unlikely */
Takashi Iwaibb009452014-02-04 18:18:16 +0100312 dev_err(card->dev, "unable to allocate new control numid\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 return -ENOMEM;
314 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 }
316 return 0;
317}
318
319/**
320 * snd_ctl_add - add the control instance to the card
321 * @card: the card instance
322 * @kcontrol: the control instance to add
323 *
324 * Adds the control instance created via snd_ctl_new() or
325 * snd_ctl_new1() to the given card. Assigns also an unique
326 * numid used for fast search.
327 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 * It frees automatically the control which cannot be added.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100329 *
330 * Return: Zero if successful, or a negative error code on failure.
331 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100333int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100335 struct snd_ctl_elem_id id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 unsigned int idx;
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200337 unsigned int count;
Takashi Iwaic6077b32006-03-21 16:07:13 +0100338 int err = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339
Takashi Iwai73e77ba2005-11-17 17:44:01 +0100340 if (! kcontrol)
Takashi Iwaic6077b32006-03-21 16:07:13 +0100341 return err;
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200342 if (snd_BUG_ON(!card || !kcontrol->info))
343 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344 id = kcontrol->id;
Lars-Peter Clausen883a1d42014-06-18 13:32:35 +0200345 if (id.index > UINT_MAX - kcontrol->count)
346 goto error;
347
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 down_write(&card->controls_rwsem);
349 if (snd_ctl_find_id(card, &id)) {
350 up_write(&card->controls_rwsem);
Takashi Iwaibb009452014-02-04 18:18:16 +0100351 dev_err(card->dev, "control %i:%i:%i:%s:%i is already present\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 id.iface,
353 id.device,
354 id.subdevice,
355 id.name,
356 id.index);
Takashi Iwaic6077b32006-03-21 16:07:13 +0100357 err = -EBUSY;
358 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 }
360 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
361 up_write(&card->controls_rwsem);
Takashi Iwaic6077b32006-03-21 16:07:13 +0100362 err = -ENOMEM;
363 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 }
365 list_add_tail(&kcontrol->list, &card->controls);
366 card->controls_count += kcontrol->count;
367 kcontrol->id.numid = card->last_numid + 1;
368 card->last_numid += kcontrol->count;
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200369 count = kcontrol->count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370 up_write(&card->controls_rwsem);
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200371 for (idx = 0; idx < count; idx++, id.index++, id.numid++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
373 return 0;
Takashi Iwaic6077b32006-03-21 16:07:13 +0100374
375 error:
376 snd_ctl_free_one(kcontrol);
377 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378}
379
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200380EXPORT_SYMBOL(snd_ctl_add);
381
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382/**
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000383 * snd_ctl_replace - replace the control instance of the card
384 * @card: the card instance
385 * @kcontrol: the control instance to replace
386 * @add_on_replace: add the control if not already added
387 *
388 * Replaces the given control. If the given control does not exist
389 * and the add_on_replace flag is set, the control is added. If the
390 * control exists, it is destroyed first.
391 *
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000392 * It frees automatically the control which cannot be added or replaced.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100393 *
394 * Return: Zero if successful, or a negative error code on failure.
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000395 */
396int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol,
397 bool add_on_replace)
398{
399 struct snd_ctl_elem_id id;
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200400 unsigned int count;
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000401 unsigned int idx;
402 struct snd_kcontrol *old;
403 int ret;
404
405 if (!kcontrol)
406 return -EINVAL;
407 if (snd_BUG_ON(!card || !kcontrol->info)) {
408 ret = -EINVAL;
409 goto error;
410 }
411 id = kcontrol->id;
412 down_write(&card->controls_rwsem);
413 old = snd_ctl_find_id(card, &id);
414 if (!old) {
415 if (add_on_replace)
416 goto add;
417 up_write(&card->controls_rwsem);
418 ret = -EINVAL;
419 goto error;
420 }
421 ret = snd_ctl_remove(card, old);
422 if (ret < 0) {
423 up_write(&card->controls_rwsem);
424 goto error;
425 }
426add:
427 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
428 up_write(&card->controls_rwsem);
429 ret = -ENOMEM;
430 goto error;
431 }
432 list_add_tail(&kcontrol->list, &card->controls);
433 card->controls_count += kcontrol->count;
434 kcontrol->id.numid = card->last_numid + 1;
435 card->last_numid += kcontrol->count;
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200436 count = kcontrol->count;
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000437 up_write(&card->controls_rwsem);
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200438 for (idx = 0; idx < count; idx++, id.index++, id.numid++)
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000439 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
440 return 0;
441
442error:
443 snd_ctl_free_one(kcontrol);
444 return ret;
445}
446EXPORT_SYMBOL(snd_ctl_replace);
447
448/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 * snd_ctl_remove - remove the control from the card and release it
450 * @card: the card instance
451 * @kcontrol: the control instance to remove
452 *
453 * Removes the control from the card and then releases the instance.
454 * You don't need to call snd_ctl_free_one(). You must be in
455 * the write lock - down_write(&card->controls_rwsem).
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100456 *
457 * Return: 0 if successful, or a negative error code on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100459int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100461 struct snd_ctl_elem_id id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 unsigned int idx;
463
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200464 if (snd_BUG_ON(!card || !kcontrol))
465 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 list_del(&kcontrol->list);
467 card->controls_count -= kcontrol->count;
468 id = kcontrol->id;
469 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
470 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
471 snd_ctl_free_one(kcontrol);
472 return 0;
473}
474
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200475EXPORT_SYMBOL(snd_ctl_remove);
476
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477/**
478 * snd_ctl_remove_id - remove the control of the given id and release it
479 * @card: the card instance
480 * @id: the control id to remove
481 *
482 * Finds the control instance with the given id, removes it from the
483 * card list and releases it.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100484 *
485 * Return: 0 if successful, or a negative error code on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100487int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100489 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 int ret;
491
492 down_write(&card->controls_rwsem);
493 kctl = snd_ctl_find_id(card, id);
494 if (kctl == NULL) {
495 up_write(&card->controls_rwsem);
496 return -ENOENT;
497 }
498 ret = snd_ctl_remove(card, kctl);
499 up_write(&card->controls_rwsem);
500 return ret;
501}
502
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200503EXPORT_SYMBOL(snd_ctl_remove_id);
504
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505/**
Clemens Ladischf217ac52009-08-17 12:27:22 +0200506 * snd_ctl_remove_user_ctl - remove and release the unlocked user control
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507 * @file: active control handle
508 * @id: the control id to remove
509 *
510 * Finds the control instance with the given id, removes it from the
511 * card list and releases it.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100512 *
513 * Return: 0 if successful, or a negative error code on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514 */
Clemens Ladischf217ac52009-08-17 12:27:22 +0200515static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
516 struct snd_ctl_elem_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100518 struct snd_card *card = file->card;
519 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 int idx, ret;
521
522 down_write(&card->controls_rwsem);
523 kctl = snd_ctl_find_id(card, id);
524 if (kctl == NULL) {
Clemens Ladisch317b8082009-08-17 12:26:34 +0200525 ret = -ENOENT;
526 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 }
Clemens Ladisch18dd0aa2009-08-17 12:28:09 +0200528 if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
529 ret = -EINVAL;
530 goto error;
531 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532 for (idx = 0; idx < kctl->count; idx++)
533 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
Clemens Ladisch317b8082009-08-17 12:26:34 +0200534 ret = -EBUSY;
535 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 }
537 ret = snd_ctl_remove(card, kctl);
Clemens Ladischf217ac52009-08-17 12:27:22 +0200538 if (ret < 0)
539 goto error;
540 card->user_ctl_count--;
Clemens Ladisch317b8082009-08-17 12:26:34 +0200541error:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 up_write(&card->controls_rwsem);
543 return ret;
544}
545
546/**
Takashi Iwai3cbdd752008-08-29 16:09:01 +0200547 * snd_ctl_activate_id - activate/inactivate the control of the given id
548 * @card: the card instance
549 * @id: the control id to activate/inactivate
550 * @active: non-zero to activate
551 *
552 * Finds the control instance with the given id, and activate or
553 * inactivate the control together with notification, if changed.
554 *
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100555 * Return: 0 if unchanged, 1 if changed, or a negative error code on failure.
Takashi Iwai3cbdd752008-08-29 16:09:01 +0200556 */
557int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
558 int active)
559{
560 struct snd_kcontrol *kctl;
561 struct snd_kcontrol_volatile *vd;
562 unsigned int index_offset;
563 int ret;
564
565 down_write(&card->controls_rwsem);
566 kctl = snd_ctl_find_id(card, id);
567 if (kctl == NULL) {
568 ret = -ENOENT;
569 goto unlock;
570 }
571 index_offset = snd_ctl_get_ioff(kctl, &kctl->id);
572 vd = &kctl->vd[index_offset];
573 ret = 0;
574 if (active) {
575 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE))
576 goto unlock;
577 vd->access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
578 } else {
579 if (vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE)
580 goto unlock;
581 vd->access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE;
582 }
583 ret = 1;
584 unlock:
585 up_write(&card->controls_rwsem);
586 if (ret > 0)
587 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, id);
588 return ret;
589}
590EXPORT_SYMBOL_GPL(snd_ctl_activate_id);
591
592/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 * snd_ctl_rename_id - replace the id of a control on the card
594 * @card: the card instance
595 * @src_id: the old id
596 * @dst_id: the new id
597 *
598 * Finds the control with the old id from the card, and replaces the
599 * id with the new one.
600 *
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100601 * Return: Zero if successful, or a negative error code on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100603int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
604 struct snd_ctl_elem_id *dst_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100606 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607
608 down_write(&card->controls_rwsem);
609 kctl = snd_ctl_find_id(card, src_id);
610 if (kctl == NULL) {
611 up_write(&card->controls_rwsem);
612 return -ENOENT;
613 }
614 kctl->id = *dst_id;
615 kctl->id.numid = card->last_numid + 1;
616 card->last_numid += kctl->count;
617 up_write(&card->controls_rwsem);
618 return 0;
619}
620
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200621EXPORT_SYMBOL(snd_ctl_rename_id);
622
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623/**
624 * snd_ctl_find_numid - find the control instance with the given number-id
625 * @card: the card instance
626 * @numid: the number-id to search
627 *
628 * Finds the control instance with the given number-id from the card.
629 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 * The caller must down card->controls_rwsem before calling this function
631 * (if the race condition can happen).
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100632 *
633 * Return: The pointer of the instance if found, or %NULL if not.
634 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100636struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100638 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200640 if (snd_BUG_ON(!card || !numid))
641 return NULL;
Johannes Berg9244b2c2006-10-05 16:02:22 +0200642 list_for_each_entry(kctl, &card->controls, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
644 return kctl;
645 }
646 return NULL;
647}
648
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200649EXPORT_SYMBOL(snd_ctl_find_numid);
650
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651/**
652 * snd_ctl_find_id - find the control instance with the given id
653 * @card: the card instance
654 * @id: the id to search
655 *
656 * Finds the control instance with the given id from the card.
657 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 * The caller must down card->controls_rwsem before calling this function
659 * (if the race condition can happen).
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100660 *
661 * Return: The pointer of the instance if found, or %NULL if not.
662 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100664struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
665 struct snd_ctl_elem_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100667 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200669 if (snd_BUG_ON(!card || !id))
670 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 if (id->numid != 0)
672 return snd_ctl_find_numid(card, id->numid);
Johannes Berg9244b2c2006-10-05 16:02:22 +0200673 list_for_each_entry(kctl, &card->controls, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 if (kctl->id.iface != id->iface)
675 continue;
676 if (kctl->id.device != id->device)
677 continue;
678 if (kctl->id.subdevice != id->subdevice)
679 continue;
680 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
681 continue;
682 if (kctl->id.index > id->index)
683 continue;
684 if (kctl->id.index + kctl->count <= id->index)
685 continue;
686 return kctl;
687 }
688 return NULL;
689}
690
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200691EXPORT_SYMBOL(snd_ctl_find_id);
692
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100693static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694 unsigned int cmd, void __user *arg)
695{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100696 struct snd_ctl_card_info *info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697
Takashi Iwaica2c0962005-09-09 14:20:23 +0200698 info = kzalloc(sizeof(*info), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699 if (! info)
700 return -ENOMEM;
701 down_read(&snd_ioctl_rwsem);
702 info->card = card->number;
703 strlcpy(info->id, card->id, sizeof(info->id));
704 strlcpy(info->driver, card->driver, sizeof(info->driver));
705 strlcpy(info->name, card->shortname, sizeof(info->name));
706 strlcpy(info->longname, card->longname, sizeof(info->longname));
707 strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
708 strlcpy(info->components, card->components, sizeof(info->components));
709 up_read(&snd_ioctl_rwsem);
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100710 if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 kfree(info);
712 return -EFAULT;
713 }
714 kfree(info);
715 return 0;
716}
717
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100718static int snd_ctl_elem_list(struct snd_card *card,
719 struct snd_ctl_elem_list __user *_list)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720{
721 struct list_head *plist;
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100722 struct snd_ctl_elem_list list;
723 struct snd_kcontrol *kctl;
724 struct snd_ctl_elem_id *dst, *id;
Luca Tettamanti78fa2c42011-05-25 22:43:27 +0200725 unsigned int offset, space, jidx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726
727 if (copy_from_user(&list, _list, sizeof(list)))
728 return -EFAULT;
729 offset = list.offset;
730 space = list.space;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 /* try limit maximum space */
732 if (space > 16384)
733 return -ENOMEM;
734 if (space > 0) {
735 /* allocate temporary buffer for atomic operation */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100736 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737 if (dst == NULL)
738 return -ENOMEM;
739 down_read(&card->controls_rwsem);
740 list.count = card->controls_count;
741 plist = card->controls.next;
742 while (plist != &card->controls) {
743 if (offset == 0)
744 break;
745 kctl = snd_kcontrol(plist);
746 if (offset < kctl->count)
747 break;
748 offset -= kctl->count;
749 plist = plist->next;
750 }
751 list.used = 0;
752 id = dst;
753 while (space > 0 && plist != &card->controls) {
754 kctl = snd_kcontrol(plist);
755 for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
756 snd_ctl_build_ioff(id, kctl, jidx);
757 id++;
758 space--;
759 list.used++;
760 }
761 plist = plist->next;
762 offset = 0;
763 }
764 up_read(&card->controls_rwsem);
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100765 if (list.used > 0 &&
766 copy_to_user(list.pids, dst,
767 list.used * sizeof(struct snd_ctl_elem_id))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768 vfree(dst);
769 return -EFAULT;
770 }
771 vfree(dst);
772 } else {
773 down_read(&card->controls_rwsem);
774 list.count = card->controls_count;
775 up_read(&card->controls_rwsem);
776 }
777 if (copy_to_user(_list, &list, sizeof(list)))
778 return -EFAULT;
779 return 0;
780}
781
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100782static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
783 struct snd_ctl_elem_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100785 struct snd_card *card = ctl->card;
786 struct snd_kcontrol *kctl;
787 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788 unsigned int index_offset;
789 int result;
790
791 down_read(&card->controls_rwsem);
792 kctl = snd_ctl_find_id(card, &info->id);
793 if (kctl == NULL) {
794 up_read(&card->controls_rwsem);
795 return -ENOENT;
796 }
797#ifdef CONFIG_SND_DEBUG
798 info->access = 0;
799#endif
800 result = kctl->info(kctl, info);
801 if (result >= 0) {
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200802 snd_BUG_ON(info->access);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700803 index_offset = snd_ctl_get_ioff(kctl, &info->id);
804 vd = &kctl->vd[index_offset];
805 snd_ctl_build_ioff(&info->id, kctl, index_offset);
806 info->access = vd->access;
807 if (vd->owner) {
808 info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
809 if (vd->owner == ctl)
810 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
Clemens Ladisch25d27ed2009-11-02 09:35:44 +0100811 info->owner = pid_vnr(vd->owner->pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 } else {
813 info->owner = -1;
814 }
815 }
816 up_read(&card->controls_rwsem);
817 return result;
818}
819
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100820static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
821 struct snd_ctl_elem_info __user *_info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100823 struct snd_ctl_elem_info info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824 int result;
825
826 if (copy_from_user(&info, _info, sizeof(info)))
827 return -EFAULT;
Giuliano Pochini64649402006-03-13 14:11:11 +0100828 snd_power_lock(ctl->card);
Takashi Iwaicbac4b02006-03-27 12:38:07 +0200829 result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
Giuliano Pochini64649402006-03-13 14:11:11 +0100830 if (result >= 0)
831 result = snd_ctl_elem_info(ctl, &info);
832 snd_power_unlock(ctl->card);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833 if (result >= 0)
834 if (copy_to_user(_info, &info, sizeof(info)))
835 return -EFAULT;
836 return result;
837}
838
Takashi Iwaid3bd67c2008-06-12 18:17:26 +0200839static int snd_ctl_elem_read(struct snd_card *card,
840 struct snd_ctl_elem_value *control)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100842 struct snd_kcontrol *kctl;
843 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844 unsigned int index_offset;
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100845 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846
847 down_read(&card->controls_rwsem);
848 kctl = snd_ctl_find_id(card, &control->id);
849 if (kctl == NULL) {
850 result = -ENOENT;
851 } else {
852 index_offset = snd_ctl_get_ioff(kctl, &control->id);
853 vd = &kctl->vd[index_offset];
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100854 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
855 kctl->get != NULL) {
856 snd_ctl_build_ioff(&control->id, kctl, index_offset);
857 result = kctl->get(kctl, control);
858 } else
859 result = -EPERM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860 }
861 up_read(&card->controls_rwsem);
862 return result;
863}
864
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100865static int snd_ctl_elem_read_user(struct snd_card *card,
866 struct snd_ctl_elem_value __user *_control)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100868 struct snd_ctl_elem_value *control;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869 int result;
Li Zefanef44a1e2009-04-10 09:43:08 +0800870
871 control = memdup_user(_control, sizeof(*control));
872 if (IS_ERR(control))
873 return PTR_ERR(control);
874
Giuliano Pochini64649402006-03-13 14:11:11 +0100875 snd_power_lock(card);
Takashi Iwaicbac4b02006-03-27 12:38:07 +0200876 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
Giuliano Pochini64649402006-03-13 14:11:11 +0100877 if (result >= 0)
878 result = snd_ctl_elem_read(card, control);
879 snd_power_unlock(card);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880 if (result >= 0)
881 if (copy_to_user(_control, control, sizeof(*control)))
882 result = -EFAULT;
883 kfree(control);
884 return result;
885}
886
Takashi Iwaid3bd67c2008-06-12 18:17:26 +0200887static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
888 struct snd_ctl_elem_value *control)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100890 struct snd_kcontrol *kctl;
891 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892 unsigned int index_offset;
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100893 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894
895 down_read(&card->controls_rwsem);
896 kctl = snd_ctl_find_id(card, &control->id);
897 if (kctl == NULL) {
898 result = -ENOENT;
899 } else {
900 index_offset = snd_ctl_get_ioff(kctl, &control->id);
901 vd = &kctl->vd[index_offset];
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100902 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
903 kctl->put == NULL ||
904 (file && vd->owner && vd->owner != file)) {
905 result = -EPERM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906 } else {
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100907 snd_ctl_build_ioff(&control->id, kctl, index_offset);
908 result = kctl->put(kctl, control);
909 }
910 if (result > 0) {
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200911 struct snd_ctl_elem_id id = control->id;
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100912 up_read(&card->controls_rwsem);
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200913 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, &id);
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100914 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915 }
916 }
917 up_read(&card->controls_rwsem);
918 return result;
919}
920
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100921static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
922 struct snd_ctl_elem_value __user *_control)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700923{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100924 struct snd_ctl_elem_value *control;
Giuliano Pochini64649402006-03-13 14:11:11 +0100925 struct snd_card *card;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926 int result;
927
Li Zefanef44a1e2009-04-10 09:43:08 +0800928 control = memdup_user(_control, sizeof(*control));
929 if (IS_ERR(control))
930 return PTR_ERR(control);
931
Giuliano Pochini64649402006-03-13 14:11:11 +0100932 card = file->card;
933 snd_power_lock(card);
Takashi Iwaicbac4b02006-03-27 12:38:07 +0200934 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
Giuliano Pochini64649402006-03-13 14:11:11 +0100935 if (result >= 0)
936 result = snd_ctl_elem_write(card, file, control);
937 snd_power_unlock(card);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 if (result >= 0)
939 if (copy_to_user(_control, control, sizeof(*control)))
940 result = -EFAULT;
941 kfree(control);
942 return result;
943}
944
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100945static int snd_ctl_elem_lock(struct snd_ctl_file *file,
946 struct snd_ctl_elem_id __user *_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100948 struct snd_card *card = file->card;
949 struct snd_ctl_elem_id id;
950 struct snd_kcontrol *kctl;
951 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952 int result;
953
954 if (copy_from_user(&id, _id, sizeof(id)))
955 return -EFAULT;
956 down_write(&card->controls_rwsem);
957 kctl = snd_ctl_find_id(card, &id);
958 if (kctl == NULL) {
959 result = -ENOENT;
960 } else {
961 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
962 if (vd->owner != NULL)
963 result = -EBUSY;
964 else {
965 vd->owner = file;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700966 result = 0;
967 }
968 }
969 up_write(&card->controls_rwsem);
970 return result;
971}
972
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100973static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
974 struct snd_ctl_elem_id __user *_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100976 struct snd_card *card = file->card;
977 struct snd_ctl_elem_id id;
978 struct snd_kcontrol *kctl;
979 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 int result;
981
982 if (copy_from_user(&id, _id, sizeof(id)))
983 return -EFAULT;
984 down_write(&card->controls_rwsem);
985 kctl = snd_ctl_find_id(card, &id);
986 if (kctl == NULL) {
987 result = -ENOENT;
988 } else {
989 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
990 if (vd->owner == NULL)
991 result = -EINVAL;
992 else if (vd->owner != file)
993 result = -EPERM;
994 else {
995 vd->owner = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 result = 0;
997 }
998 }
999 up_write(&card->controls_rwsem);
1000 return result;
1001}
1002
1003struct user_element {
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001004 struct snd_ctl_elem_info info;
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001005 struct snd_card *card;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 void *elem_data; /* element data */
1007 unsigned long elem_data_size; /* size of element data in bytes */
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001008 void *tlv_data; /* TLV data */
1009 unsigned long tlv_data_size; /* TLV data size */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001010 void *priv_data; /* private data (like strings for enumerated type) */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011};
1012
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001013static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
1014 struct snd_ctl_elem_info *uinfo)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015{
1016 struct user_element *ue = kcontrol->private_data;
1017
1018 *uinfo = ue->info;
1019 return 0;
1020}
1021
Clemens Ladisch8d448162011-10-07 22:38:59 +02001022static int snd_ctl_elem_user_enum_info(struct snd_kcontrol *kcontrol,
1023 struct snd_ctl_elem_info *uinfo)
1024{
1025 struct user_element *ue = kcontrol->private_data;
1026 const char *names;
1027 unsigned int item;
1028
1029 item = uinfo->value.enumerated.item;
1030
1031 *uinfo = ue->info;
1032
1033 item = min(item, uinfo->value.enumerated.items - 1);
1034 uinfo->value.enumerated.item = item;
1035
1036 names = ue->priv_data;
1037 for (; item > 0; --item)
1038 names += strlen(names) + 1;
1039 strcpy(uinfo->value.enumerated.name, names);
1040
1041 return 0;
1042}
1043
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001044static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
1045 struct snd_ctl_elem_value *ucontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046{
1047 struct user_element *ue = kcontrol->private_data;
1048
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001049 mutex_lock(&ue->card->user_ctl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001050 memcpy(&ucontrol->value, ue->elem_data, ue->elem_data_size);
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001051 mutex_unlock(&ue->card->user_ctl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052 return 0;
1053}
1054
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001055static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
1056 struct snd_ctl_elem_value *ucontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001057{
1058 int change;
1059 struct user_element *ue = kcontrol->private_data;
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001060
1061 mutex_lock(&ue->card->user_ctl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001062 change = memcmp(&ucontrol->value, ue->elem_data, ue->elem_data_size) != 0;
1063 if (change)
1064 memcpy(ue->elem_data, &ucontrol->value, ue->elem_data_size);
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001065 mutex_unlock(&ue->card->user_ctl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066 return change;
1067}
1068
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001069static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
1070 int op_flag,
1071 unsigned int size,
1072 unsigned int __user *tlv)
1073{
1074 struct user_element *ue = kcontrol->private_data;
1075 int change = 0;
1076 void *new_data;
1077
1078 if (op_flag > 0) {
1079 if (size > 1024 * 128) /* sane value */
1080 return -EINVAL;
Li Zefanef44a1e2009-04-10 09:43:08 +08001081
1082 new_data = memdup_user(tlv, size);
1083 if (IS_ERR(new_data))
1084 return PTR_ERR(new_data);
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001085 mutex_lock(&ue->card->user_ctl_lock);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001086 change = ue->tlv_data_size != size;
1087 if (!change)
1088 change = memcmp(ue->tlv_data, new_data, size);
1089 kfree(ue->tlv_data);
1090 ue->tlv_data = new_data;
1091 ue->tlv_data_size = size;
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001092 mutex_unlock(&ue->card->user_ctl_lock);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001093 } else {
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001094 int ret = 0;
1095
1096 mutex_lock(&ue->card->user_ctl_lock);
1097 if (!ue->tlv_data_size || !ue->tlv_data) {
1098 ret = -ENXIO;
1099 goto err_unlock;
1100 }
1101 if (size < ue->tlv_data_size) {
1102 ret = -ENOSPC;
1103 goto err_unlock;
1104 }
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001105 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001106 ret = -EFAULT;
1107err_unlock:
1108 mutex_unlock(&ue->card->user_ctl_lock);
1109 if (ret)
1110 return ret;
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001111 }
1112 return change;
1113}
1114
Clemens Ladisch8d448162011-10-07 22:38:59 +02001115static int snd_ctl_elem_init_enum_names(struct user_element *ue)
1116{
1117 char *names, *p;
1118 size_t buf_len, name_len;
1119 unsigned int i;
Olof Johansson447c6f92011-11-05 22:51:54 +01001120 const uintptr_t user_ptrval = ue->info.value.enumerated.names_ptr;
Clemens Ladisch8d448162011-10-07 22:38:59 +02001121
1122 if (ue->info.value.enumerated.names_length > 64 * 1024)
1123 return -EINVAL;
1124
Olof Johansson447c6f92011-11-05 22:51:54 +01001125 names = memdup_user((const void __user *)user_ptrval,
Clemens Ladisch8d448162011-10-07 22:38:59 +02001126 ue->info.value.enumerated.names_length);
1127 if (IS_ERR(names))
1128 return PTR_ERR(names);
1129
1130 /* check that there are enough valid names */
1131 buf_len = ue->info.value.enumerated.names_length;
1132 p = names;
1133 for (i = 0; i < ue->info.value.enumerated.items; ++i) {
1134 name_len = strnlen(p, buf_len);
1135 if (name_len == 0 || name_len >= 64 || name_len == buf_len) {
1136 kfree(names);
1137 return -EINVAL;
1138 }
1139 p += name_len + 1;
1140 buf_len -= name_len + 1;
1141 }
1142
1143 ue->priv_data = names;
1144 ue->info.value.enumerated.names_ptr = 0;
1145
1146 return 0;
1147}
1148
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001149static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150{
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001151 struct user_element *ue = kcontrol->private_data;
Clemens Ladisch8d448162011-10-07 22:38:59 +02001152
1153 kfree(ue->tlv_data);
1154 kfree(ue->priv_data);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001155 kfree(ue);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001156}
1157
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001158static int snd_ctl_elem_add(struct snd_ctl_file *file,
1159 struct snd_ctl_elem_info *info, int replace)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001160{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001161 struct snd_card *card = file->card;
1162 struct snd_kcontrol kctl, *_kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001163 unsigned int access;
1164 long private_size;
1165 struct user_element *ue;
1166 int idx, err;
Lu Guanqun983929c2011-08-24 11:12:34 +08001167
Clemens Ladisch2a031ae2009-08-17 12:25:52 +02001168 if (info->count < 1)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001169 return -EINVAL;
1170 access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001171 (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001172 SNDRV_CTL_ELEM_ACCESS_INACTIVE|
1173 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001174 info->id.numid = 0;
1175 memset(&kctl, 0, sizeof(kctl));
Lars-Peter Clausen82262a462014-06-18 13:32:32 +02001176
1177 if (replace) {
1178 err = snd_ctl_remove_user_ctl(file, &info->id);
1179 if (err)
1180 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001181 }
Lars-Peter Clausen82262a462014-06-18 13:32:32 +02001182
1183 if (card->user_ctl_count >= MAX_USER_CONTROLS)
1184 return -ENOMEM;
1185
Linus Torvalds1da177e2005-04-16 15:20:36 -07001186 memcpy(&kctl.id, &info->id, sizeof(info->id));
1187 kctl.count = info->owner ? info->owner : 1;
1188 access |= SNDRV_CTL_ELEM_ACCESS_USER;
Clemens Ladisch8d448162011-10-07 22:38:59 +02001189 if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED)
1190 kctl.info = snd_ctl_elem_user_enum_info;
1191 else
1192 kctl.info = snd_ctl_elem_user_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001193 if (access & SNDRV_CTL_ELEM_ACCESS_READ)
1194 kctl.get = snd_ctl_elem_user_get;
1195 if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
1196 kctl.put = snd_ctl_elem_user_put;
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001197 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
1198 kctl.tlv.c = snd_ctl_elem_user_tlv;
1199 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1200 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001201 switch (info->type) {
1202 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001203 case SNDRV_CTL_ELEM_TYPE_INTEGER:
1204 private_size = sizeof(long);
1205 if (info->count > 128)
1206 return -EINVAL;
1207 break;
1208 case SNDRV_CTL_ELEM_TYPE_INTEGER64:
1209 private_size = sizeof(long long);
1210 if (info->count > 64)
1211 return -EINVAL;
1212 break;
Clemens Ladisch8d448162011-10-07 22:38:59 +02001213 case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
1214 private_size = sizeof(unsigned int);
1215 if (info->count > 128 || info->value.enumerated.items == 0)
1216 return -EINVAL;
1217 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001218 case SNDRV_CTL_ELEM_TYPE_BYTES:
1219 private_size = sizeof(unsigned char);
1220 if (info->count > 512)
1221 return -EINVAL;
1222 break;
1223 case SNDRV_CTL_ELEM_TYPE_IEC958:
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001224 private_size = sizeof(struct snd_aes_iec958);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001225 if (info->count != 1)
1226 return -EINVAL;
1227 break;
1228 default:
1229 return -EINVAL;
1230 }
1231 private_size *= info->count;
Takashi Iwaica2c0962005-09-09 14:20:23 +02001232 ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233 if (ue == NULL)
1234 return -ENOMEM;
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001235 ue->card = card;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001236 ue->info = *info;
Takashi Iwai86148e82006-08-24 12:36:36 +02001237 ue->info.access = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238 ue->elem_data = (char *)ue + sizeof(*ue);
1239 ue->elem_data_size = private_size;
Clemens Ladisch8d448162011-10-07 22:38:59 +02001240 if (ue->info.type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) {
1241 err = snd_ctl_elem_init_enum_names(ue);
1242 if (err < 0) {
1243 kfree(ue);
1244 return err;
1245 }
1246 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001247 kctl.private_free = snd_ctl_elem_user_free;
1248 _kctl = snd_ctl_new(&kctl, access);
1249 if (_kctl == NULL) {
Clemens Ladisch8d448162011-10-07 22:38:59 +02001250 kfree(ue->priv_data);
Takashi Iwai2fbf1822006-03-06 15:42:51 -08001251 kfree(ue);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001252 return -ENOMEM;
1253 }
1254 _kctl->private_data = ue;
1255 for (idx = 0; idx < _kctl->count; idx++)
1256 _kctl->vd[idx].owner = file;
1257 err = snd_ctl_add(card, _kctl);
Takashi Iwai2fbf1822006-03-06 15:42:51 -08001258 if (err < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001260
1261 down_write(&card->controls_rwsem);
1262 card->user_ctl_count++;
1263 up_write(&card->controls_rwsem);
1264
1265 return 0;
1266}
1267
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001268static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1269 struct snd_ctl_elem_info __user *_info, int replace)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001270{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001271 struct snd_ctl_elem_info info;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001272 if (copy_from_user(&info, _info, sizeof(info)))
1273 return -EFAULT;
1274 return snd_ctl_elem_add(file, &info, replace);
1275}
1276
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001277static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1278 struct snd_ctl_elem_id __user *_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001279{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001280 struct snd_ctl_elem_id id;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281
1282 if (copy_from_user(&id, _id, sizeof(id)))
1283 return -EFAULT;
Clemens Ladischf217ac52009-08-17 12:27:22 +02001284 return snd_ctl_remove_user_ctl(file, &id);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001285}
1286
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001287static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001288{
1289 int subscribe;
1290 if (get_user(subscribe, ptr))
1291 return -EFAULT;
1292 if (subscribe < 0) {
1293 subscribe = file->subscribed;
1294 if (put_user(subscribe, ptr))
1295 return -EFAULT;
1296 return 0;
1297 }
1298 if (subscribe) {
1299 file->subscribed = 1;
1300 return 0;
1301 } else if (file->subscribed) {
1302 snd_ctl_empty_read_queue(file);
1303 file->subscribed = 0;
1304 }
1305 return 0;
1306}
1307
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001308static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1309 struct snd_ctl_tlv __user *_tlv,
1310 int op_flag)
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001311{
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001312 struct snd_card *card = file->card;
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001313 struct snd_ctl_tlv tlv;
1314 struct snd_kcontrol *kctl;
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001315 struct snd_kcontrol_volatile *vd;
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001316 unsigned int len;
1317 int err = 0;
1318
1319 if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1320 return -EFAULT;
Clemens Ladisch61236372010-02-01 13:30:56 +01001321 if (tlv.length < sizeof(unsigned int) * 2)
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001322 return -EINVAL;
1323 down_read(&card->controls_rwsem);
1324 kctl = snd_ctl_find_numid(card, tlv.numid);
1325 if (kctl == NULL) {
1326 err = -ENOENT;
1327 goto __kctl_end;
1328 }
1329 if (kctl->tlv.p == NULL) {
1330 err = -ENXIO;
1331 goto __kctl_end;
1332 }
1333 vd = &kctl->vd[tlv.numid - kctl->id.numid];
1334 if ((op_flag == 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1335 (op_flag > 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1336 (op_flag < 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
1337 err = -ENXIO;
1338 goto __kctl_end;
1339 }
1340 if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
Dan Carpenterbec145a2009-11-18 10:31:57 +02001341 if (vd->owner != NULL && vd->owner != file) {
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001342 err = -EPERM;
1343 goto __kctl_end;
1344 }
Jeffrin Josebd483d42012-03-07 22:57:39 +05301345 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001346 if (err > 0) {
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +02001347 struct snd_ctl_elem_id id = kctl->id;
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001348 up_read(&card->controls_rwsem);
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +02001349 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &id);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001350 return 0;
1351 }
1352 } else {
1353 if (op_flag) {
1354 err = -ENXIO;
1355 goto __kctl_end;
1356 }
1357 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1358 if (tlv.length < len) {
1359 err = -ENOMEM;
1360 goto __kctl_end;
1361 }
1362 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1363 err = -EFAULT;
1364 }
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001365 __kctl_end:
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001366 up_read(&card->controls_rwsem);
1367 return err;
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001368}
1369
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1371{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001372 struct snd_ctl_file *ctl;
1373 struct snd_card *card;
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001374 struct snd_kctl_ioctl *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001375 void __user *argp = (void __user *)arg;
1376 int __user *ip = argp;
1377 int err;
1378
1379 ctl = file->private_data;
1380 card = ctl->card;
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001381 if (snd_BUG_ON(!card))
1382 return -ENXIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001383 switch (cmd) {
1384 case SNDRV_CTL_IOCTL_PVERSION:
1385 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1386 case SNDRV_CTL_IOCTL_CARD_INFO:
1387 return snd_ctl_card_info(card, ctl, cmd, argp);
1388 case SNDRV_CTL_IOCTL_ELEM_LIST:
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001389 return snd_ctl_elem_list(card, argp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001390 case SNDRV_CTL_IOCTL_ELEM_INFO:
1391 return snd_ctl_elem_info_user(ctl, argp);
1392 case SNDRV_CTL_IOCTL_ELEM_READ:
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001393 return snd_ctl_elem_read_user(card, argp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394 case SNDRV_CTL_IOCTL_ELEM_WRITE:
1395 return snd_ctl_elem_write_user(ctl, argp);
1396 case SNDRV_CTL_IOCTL_ELEM_LOCK:
1397 return snd_ctl_elem_lock(ctl, argp);
1398 case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1399 return snd_ctl_elem_unlock(ctl, argp);
1400 case SNDRV_CTL_IOCTL_ELEM_ADD:
1401 return snd_ctl_elem_add_user(ctl, argp, 0);
1402 case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1403 return snd_ctl_elem_add_user(ctl, argp, 1);
1404 case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1405 return snd_ctl_elem_remove(ctl, argp);
1406 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1407 return snd_ctl_subscribe_events(ctl, ip);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001408 case SNDRV_CTL_IOCTL_TLV_READ:
Takashi Iwai0cea76f2014-07-15 16:31:01 +02001409 return snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_READ);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001410 case SNDRV_CTL_IOCTL_TLV_WRITE:
Takashi Iwai0cea76f2014-07-15 16:31:01 +02001411 return snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_WRITE);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001412 case SNDRV_CTL_IOCTL_TLV_COMMAND:
Takashi Iwai0cea76f2014-07-15 16:31:01 +02001413 return snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_CMD);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001414 case SNDRV_CTL_IOCTL_POWER:
Takashi Iwaia381a7a2005-11-17 15:55:49 +01001415 return -ENOPROTOOPT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001416 case SNDRV_CTL_IOCTL_POWER_STATE:
1417#ifdef CONFIG_PM
1418 return put_user(card->power_state, ip) ? -EFAULT : 0;
1419#else
1420 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1421#endif
1422 }
1423 down_read(&snd_ioctl_rwsem);
Johannes Berg9244b2c2006-10-05 16:02:22 +02001424 list_for_each_entry(p, &snd_control_ioctls, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001425 err = p->fioctl(card, ctl, cmd, arg);
1426 if (err != -ENOIOCTLCMD) {
1427 up_read(&snd_ioctl_rwsem);
1428 return err;
1429 }
1430 }
1431 up_read(&snd_ioctl_rwsem);
Takashi Iwaibb009452014-02-04 18:18:16 +01001432 dev_dbg(card->dev, "unknown ioctl = 0x%x\n", cmd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001433 return -ENOTTY;
1434}
1435
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001436static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1437 size_t count, loff_t * offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001438{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001439 struct snd_ctl_file *ctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001440 int err = 0;
1441 ssize_t result = 0;
1442
1443 ctl = file->private_data;
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001444 if (snd_BUG_ON(!ctl || !ctl->card))
1445 return -ENXIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001446 if (!ctl->subscribed)
1447 return -EBADFD;
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001448 if (count < sizeof(struct snd_ctl_event))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001449 return -EINVAL;
1450 spin_lock_irq(&ctl->read_lock);
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001451 while (count >= sizeof(struct snd_ctl_event)) {
1452 struct snd_ctl_event ev;
1453 struct snd_kctl_event *kev;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454 while (list_empty(&ctl->events)) {
1455 wait_queue_t wait;
1456 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1457 err = -EAGAIN;
1458 goto __end_lock;
1459 }
1460 init_waitqueue_entry(&wait, current);
1461 add_wait_queue(&ctl->change_sleep, &wait);
1462 set_current_state(TASK_INTERRUPTIBLE);
1463 spin_unlock_irq(&ctl->read_lock);
1464 schedule();
1465 remove_wait_queue(&ctl->change_sleep, &wait);
Takashi Iwai0914f792012-10-16 16:43:39 +02001466 if (ctl->card->shutdown)
1467 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468 if (signal_pending(current))
Adrian Bunk0e5d7202006-11-07 13:42:54 +01001469 return -ERESTARTSYS;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001470 spin_lock_irq(&ctl->read_lock);
1471 }
1472 kev = snd_kctl_event(ctl->events.next);
1473 ev.type = SNDRV_CTL_EVENT_ELEM;
1474 ev.data.elem.mask = kev->mask;
1475 ev.data.elem.id = kev->id;
1476 list_del(&kev->list);
1477 spin_unlock_irq(&ctl->read_lock);
1478 kfree(kev);
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001479 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001480 err = -EFAULT;
1481 goto __end;
1482 }
1483 spin_lock_irq(&ctl->read_lock);
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001484 buffer += sizeof(struct snd_ctl_event);
1485 count -= sizeof(struct snd_ctl_event);
1486 result += sizeof(struct snd_ctl_event);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487 }
1488 __end_lock:
1489 spin_unlock_irq(&ctl->read_lock);
1490 __end:
1491 return result > 0 ? result : err;
1492}
1493
1494static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1495{
1496 unsigned int mask;
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001497 struct snd_ctl_file *ctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001498
1499 ctl = file->private_data;
1500 if (!ctl->subscribed)
1501 return 0;
1502 poll_wait(file, &ctl->change_sleep, wait);
1503
1504 mask = 0;
1505 if (!list_empty(&ctl->events))
1506 mask |= POLLIN | POLLRDNORM;
1507
1508 return mask;
1509}
1510
1511/*
1512 * register the device-specific control-ioctls.
1513 * called from each device manager like pcm.c, hwdep.c, etc.
1514 */
1515static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1516{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001517 struct snd_kctl_ioctl *pn;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001518
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001519 pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001520 if (pn == NULL)
1521 return -ENOMEM;
1522 pn->fioctl = fcn;
1523 down_write(&snd_ioctl_rwsem);
1524 list_add_tail(&pn->list, lists);
1525 up_write(&snd_ioctl_rwsem);
1526 return 0;
1527}
1528
1529int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1530{
1531 return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1532}
1533
Takashi Iwaic0d3fb32006-04-28 15:13:39 +02001534EXPORT_SYMBOL(snd_ctl_register_ioctl);
1535
Linus Torvalds1da177e2005-04-16 15:20:36 -07001536#ifdef CONFIG_COMPAT
1537int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1538{
1539 return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1540}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +02001541
1542EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001543#endif
1544
1545/*
1546 * de-register the device-specific control-ioctls.
1547 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001548static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1549 struct list_head *lists)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001550{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001551 struct snd_kctl_ioctl *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001552
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001553 if (snd_BUG_ON(!fcn))
1554 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001555 down_write(&snd_ioctl_rwsem);
Johannes Berg9244b2c2006-10-05 16:02:22 +02001556 list_for_each_entry(p, lists, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001557 if (p->fioctl == fcn) {
1558 list_del(&p->list);
1559 up_write(&snd_ioctl_rwsem);
1560 kfree(p);
1561 return 0;
1562 }
1563 }
1564 up_write(&snd_ioctl_rwsem);
1565 snd_BUG();
1566 return -EINVAL;
1567}
1568
1569int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1570{
1571 return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1572}
1573
Takashi Iwaic0d3fb32006-04-28 15:13:39 +02001574EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1575
Linus Torvalds1da177e2005-04-16 15:20:36 -07001576#ifdef CONFIG_COMPAT
1577int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1578{
1579 return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1580}
1581
Takashi Iwaic0d3fb32006-04-28 15:13:39 +02001582EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001583#endif
1584
1585static int snd_ctl_fasync(int fd, struct file * file, int on)
1586{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001587 struct snd_ctl_file *ctl;
Jonathan Corbet60aa4922009-02-01 14:52:56 -07001588
Linus Torvalds1da177e2005-04-16 15:20:36 -07001589 ctl = file->private_data;
Jonathan Corbet60aa4922009-02-01 14:52:56 -07001590 return fasync_helper(fd, file, on, &ctl->fasync);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001591}
1592
1593/*
1594 * ioctl32 compat
1595 */
1596#ifdef CONFIG_COMPAT
1597#include "control_compat.c"
1598#else
1599#define snd_ctl_ioctl_compat NULL
1600#endif
1601
1602/*
1603 * INIT PART
1604 */
1605
Arjan van de Ven9c2e08c2007-02-12 00:55:37 -08001606static const struct file_operations snd_ctl_f_ops =
Linus Torvalds1da177e2005-04-16 15:20:36 -07001607{
1608 .owner = THIS_MODULE,
1609 .read = snd_ctl_read,
1610 .open = snd_ctl_open,
1611 .release = snd_ctl_release,
Takashi Iwai02f48652010-04-13 11:49:04 +02001612 .llseek = no_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001613 .poll = snd_ctl_poll,
1614 .unlocked_ioctl = snd_ctl_ioctl,
1615 .compat_ioctl = snd_ctl_ioctl_compat,
1616 .fasync = snd_ctl_fasync,
1617};
1618
Linus Torvalds1da177e2005-04-16 15:20:36 -07001619/*
1620 * registration of the control device
1621 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001622static int snd_ctl_dev_register(struct snd_device *device)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001623{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001624 struct snd_card *card = device->device_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001625 int err, cardnum;
1626 char name[16];
1627
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001628 if (snd_BUG_ON(!card))
1629 return -ENXIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001630 cardnum = card->number;
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001631 if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1632 return -ENXIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001633 sprintf(name, "controlC%i", cardnum);
Clemens Ladischf87135f2005-11-20 14:06:59 +01001634 if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1635 &snd_ctl_f_ops, card, name)) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001636 return err;
1637 return 0;
1638}
1639
1640/*
1641 * disconnection of the control device
1642 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001643static int snd_ctl_dev_disconnect(struct snd_device *device)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001644{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001645 struct snd_card *card = device->device_data;
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001646 struct snd_ctl_file *ctl;
Takashi Iwaic4614822006-06-23 14:38:23 +02001647 int err, cardnum;
1648
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001649 if (snd_BUG_ON(!card))
1650 return -ENXIO;
Takashi Iwaic4614822006-06-23 14:38:23 +02001651 cardnum = card->number;
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001652 if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1653 return -ENXIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001654
Takashi Iwaid8009882008-09-07 12:51:13 +02001655 read_lock(&card->ctl_files_rwlock);
Johannes Berg9244b2c2006-10-05 16:02:22 +02001656 list_for_each_entry(ctl, &card->ctl_files, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 wake_up(&ctl->change_sleep);
1658 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1659 }
Takashi Iwaid8009882008-09-07 12:51:13 +02001660 read_unlock(&card->ctl_files_rwlock);
Takashi Iwaic4614822006-06-23 14:38:23 +02001661
1662 if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
1663 card, -1)) < 0)
1664 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001665 return 0;
1666}
1667
1668/*
1669 * free all controls
1670 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001671static int snd_ctl_dev_free(struct snd_device *device)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001672{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001673 struct snd_card *card = device->device_data;
1674 struct snd_kcontrol *control;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001675
1676 down_write(&card->controls_rwsem);
1677 while (!list_empty(&card->controls)) {
1678 control = snd_kcontrol(card->controls.next);
1679 snd_ctl_remove(card, control);
1680 }
1681 up_write(&card->controls_rwsem);
1682 return 0;
1683}
1684
1685/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001686 * create control core:
1687 * called from init.c
1688 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001689int snd_ctl_create(struct snd_card *card)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001690{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001691 static struct snd_device_ops ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001692 .dev_free = snd_ctl_dev_free,
1693 .dev_register = snd_ctl_dev_register,
1694 .dev_disconnect = snd_ctl_dev_disconnect,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001695 };
1696
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001697 if (snd_BUG_ON(!card))
1698 return -ENXIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001699 return snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1700}
Takashi Iwaib9ed4f22007-07-23 15:41:34 +02001701
1702/*
Clemens Ladisch96007322011-01-10 16:25:44 +01001703 * Frequently used control callbacks/helpers
Takashi Iwaib9ed4f22007-07-23 15:41:34 +02001704 */
1705int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1706 struct snd_ctl_elem_info *uinfo)
1707{
1708 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1709 uinfo->count = 1;
1710 uinfo->value.integer.min = 0;
1711 uinfo->value.integer.max = 1;
1712 return 0;
1713}
1714
1715EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1716
1717int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1718 struct snd_ctl_elem_info *uinfo)
1719{
1720 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1721 uinfo->count = 2;
1722 uinfo->value.integer.min = 0;
1723 uinfo->value.integer.max = 1;
1724 return 0;
1725}
1726
1727EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);
Clemens Ladisch96007322011-01-10 16:25:44 +01001728
1729/**
1730 * snd_ctl_enum_info - fills the info structure for an enumerated control
1731 * @info: the structure to be filled
1732 * @channels: the number of the control's channels; often one
1733 * @items: the number of control values; also the size of @names
1734 * @names: an array containing the names of all control values
1735 *
1736 * Sets all required fields in @info to their appropriate values.
1737 * If the control's accessibility is not the default (readable and writable),
1738 * the caller has to fill @info->access.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +01001739 *
1740 * Return: Zero.
Clemens Ladisch96007322011-01-10 16:25:44 +01001741 */
1742int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
1743 unsigned int items, const char *const names[])
1744{
1745 info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
1746 info->count = channels;
1747 info->value.enumerated.items = items;
1748 if (info->value.enumerated.item >= items)
1749 info->value.enumerated.item = items - 1;
1750 strlcpy(info->value.enumerated.name,
1751 names[info->value.enumerated.item],
1752 sizeof(info->value.enumerated.name));
1753 return 0;
1754}
1755EXPORT_SYMBOL(snd_ctl_enum_info);