blob: a85d45595d02a265f1f8e1a4cd36c812d8cd08f0 [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;
Takashi Iwai23c18d42014-02-19 14:30:29 +010053 int i, err;
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
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 Iwai23c18d42014-02-19 14:30:29 +010082 for (i = 0; i < SND_CTL_SUBDEV_ITEMS; i++)
83 ctl->preferred_subdevice[i] = -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 Iwai12cddbd2014-10-30 13:44:34 +0100144/**
145 * snd_ctl_notify - Send notification to user-space for a control change
146 * @card: the card to send notification
147 * @mask: the event mask, SNDRV_CTL_EVENT_*
148 * @id: the ctl element id to send notification
149 *
150 * This function adds an event record with the given id and mask, appends
151 * to the list and wakes up the user-space for notification. This can be
152 * called in the atomic context.
153 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100154void snd_ctl_notify(struct snd_card *card, unsigned int mask,
155 struct snd_ctl_elem_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156{
157 unsigned long flags;
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100158 struct snd_ctl_file *ctl;
159 struct snd_kctl_event *ev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200161 if (snd_BUG_ON(!card || !id))
162 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 read_lock(&card->ctl_files_rwlock);
Takashi Iwai8eeaa2f2014-02-10 09:48:47 +0100164#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165 card->mixer_oss_change_count++;
166#endif
Johannes Berg9244b2c2006-10-05 16:02:22 +0200167 list_for_each_entry(ctl, &card->ctl_files, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 if (!ctl->subscribed)
169 continue;
170 spin_lock_irqsave(&ctl->read_lock, flags);
Johannes Berg9244b2c2006-10-05 16:02:22 +0200171 list_for_each_entry(ev, &ctl->events, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 if (ev->id.numid == id->numid) {
173 ev->mask |= mask;
174 goto _found;
175 }
176 }
Takashi Iwaica2c0962005-09-09 14:20:23 +0200177 ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 if (ev) {
179 ev->id = *id;
180 ev->mask = mask;
181 list_add_tail(&ev->list, &ctl->events);
182 } else {
Takashi Iwaibb009452014-02-04 18:18:16 +0100183 dev_err(card->dev, "No memory available to allocate event\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 }
185 _found:
186 wake_up(&ctl->change_sleep);
187 spin_unlock_irqrestore(&ctl->read_lock, flags);
188 kill_fasync(&ctl->fasync, SIGIO, POLL_IN);
189 }
190 read_unlock(&card->ctl_files_rwlock);
191}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200192EXPORT_SYMBOL(snd_ctl_notify);
193
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194/**
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900195 * snd_ctl_new - create a new control instance with some elements
196 * @kctl: the pointer to store new control instance
197 * @count: the number of elements in this control
198 * @access: the default access flags for elements in this control
199 * @file: given when locking these elements
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 *
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900201 * Allocates a memory object for a new control instance. The instance has
202 * elements as many as the given number (@count). Each element has given
203 * access permissions (@access). Each element is locked when @file is given.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 *
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900205 * Return: 0 on success, error code on failure
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206 */
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900207static int snd_ctl_new(struct snd_kcontrol **kctl, unsigned int count,
208 unsigned int access, struct snd_ctl_file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209{
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900210 unsigned int size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 unsigned int idx;
212
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900213 if (count == 0 || count > MAX_CONTROL_COUNT)
214 return -EINVAL;
Dan Rosenberg5591bf02010-09-28 14:18:20 -0400215
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900216 size = sizeof(struct snd_kcontrol);
217 size += sizeof(struct snd_kcontrol_volatile) * count;
Dan Rosenberg5591bf02010-09-28 14:18:20 -0400218
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900219 *kctl = kzalloc(size, GFP_KERNEL);
Takashi Iwaiec0e9932015-03-10 15:42:14 +0100220 if (!*kctl)
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900221 return -ENOMEM;
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900222
223 for (idx = 0; idx < count; idx++) {
224 (*kctl)->vd[idx].access = access;
225 (*kctl)->vd[idx].owner = file;
226 }
227 (*kctl)->count = count;
228
229 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230}
231
232/**
233 * snd_ctl_new1 - create a control instance from the template
234 * @ncontrol: the initialization record
235 * @private_data: the private data to set
236 *
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100237 * Allocates a new struct snd_kcontrol instance and initialize from the given
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238 * template. When the access field of ncontrol is 0, it's assumed as
239 * READWRITE access. When the count field is 0, it's assumes as one.
240 *
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100241 * Return: The pointer of the newly generated instance, or %NULL on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100243struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
244 void *private_data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245{
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900246 struct snd_kcontrol *kctl;
247 unsigned int count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 unsigned int access;
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900249 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200251 if (snd_BUG_ON(!ncontrol || !ncontrol->info))
252 return NULL;
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900253
254 count = ncontrol->count;
255 if (count == 0)
256 count = 1;
257
258 access = ncontrol->access;
259 if (access == 0)
260 access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
261 access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE |
262 SNDRV_CTL_ELEM_ACCESS_VOLATILE |
263 SNDRV_CTL_ELEM_ACCESS_INACTIVE |
264 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE |
265 SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND |
266 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK);
267
268 err = snd_ctl_new(&kctl, count, access, NULL);
269 if (err < 0)
270 return NULL;
271
272 /* The 'numid' member is decided when calling snd_ctl_add(). */
273 kctl->id.iface = ncontrol->iface;
274 kctl->id.device = ncontrol->device;
275 kctl->id.subdevice = ncontrol->subdevice;
Mark Brown366840d2008-10-29 14:40:30 +0000276 if (ncontrol->name) {
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900277 strlcpy(kctl->id.name, ncontrol->name, sizeof(kctl->id.name));
278 if (strcmp(ncontrol->name, kctl->id.name) != 0)
Takashi Iwaibb009452014-02-04 18:18:16 +0100279 pr_warn("ALSA: Control name '%s' truncated to '%s'\n",
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900280 ncontrol->name, kctl->id.name);
Mark Brown366840d2008-10-29 14:40:30 +0000281 }
Takashi Sakamoto2225e792015-03-10 22:13:31 +0900282 kctl->id.index = ncontrol->index;
283
284 kctl->info = ncontrol->info;
285 kctl->get = ncontrol->get;
286 kctl->put = ncontrol->put;
287 kctl->tlv.p = ncontrol->tlv.p;
288
289 kctl->private_value = ncontrol->private_value;
290 kctl->private_data = private_data;
291
292 return kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200294EXPORT_SYMBOL(snd_ctl_new1);
295
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296/**
297 * snd_ctl_free_one - release the control instance
298 * @kcontrol: the control instance
299 *
300 * Releases the control instance created via snd_ctl_new()
301 * or snd_ctl_new1().
302 * Don't call this after the control was added to the card.
303 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100304void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305{
306 if (kcontrol) {
307 if (kcontrol->private_free)
308 kcontrol->private_free(kcontrol);
309 kfree(kcontrol);
310 }
311}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200312EXPORT_SYMBOL(snd_ctl_free_one);
313
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100314static bool snd_ctl_remove_numid_conflict(struct snd_card *card,
315 unsigned int count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100317 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318
Lars-Peter Clausenac902c12014-06-18 13:32:34 +0200319 /* Make sure that the ids assigned to the control do not wrap around */
320 if (card->last_numid >= UINT_MAX - count)
321 card->last_numid = 0;
322
Johannes Berg9244b2c2006-10-05 16:02:22 +0200323 list_for_each_entry(kctl, &card->controls, list) {
Clemens Ladisch7c733582011-03-07 13:22:50 +0100324 if (kctl->id.numid < card->last_numid + 1 + count &&
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100325 kctl->id.numid + kctl->count > card->last_numid + 1) {
326 card->last_numid = kctl->id.numid + kctl->count - 1;
327 return true;
328 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 }
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100330 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331}
332
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100333static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334{
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100335 unsigned int iter = 100000;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336
Clemens Ladisch0e82e5f2011-03-07 13:24:30 +0100337 while (snd_ctl_remove_numid_conflict(card, count)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 if (--iter == 0) {
339 /* this situation is very unlikely */
Takashi Iwaibb009452014-02-04 18:18:16 +0100340 dev_err(card->dev, "unable to allocate new control numid\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 return -ENOMEM;
342 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 }
344 return 0;
345}
346
347/**
348 * snd_ctl_add - add the control instance to the card
349 * @card: the card instance
350 * @kcontrol: the control instance to add
351 *
352 * Adds the control instance created via snd_ctl_new() or
353 * snd_ctl_new1() to the given card. Assigns also an unique
354 * numid used for fast search.
355 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 * It frees automatically the control which cannot be added.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100357 *
358 * Return: Zero if successful, or a negative error code on failure.
359 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100361int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100363 struct snd_ctl_elem_id id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 unsigned int idx;
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200365 unsigned int count;
Takashi Iwaic6077b32006-03-21 16:07:13 +0100366 int err = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367
Takashi Iwai73e77ba2005-11-17 17:44:01 +0100368 if (! kcontrol)
Takashi Iwaic6077b32006-03-21 16:07:13 +0100369 return err;
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200370 if (snd_BUG_ON(!card || !kcontrol->info))
371 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 id = kcontrol->id;
Lars-Peter Clausen883a1d42014-06-18 13:32:35 +0200373 if (id.index > UINT_MAX - kcontrol->count)
374 goto error;
375
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 down_write(&card->controls_rwsem);
377 if (snd_ctl_find_id(card, &id)) {
378 up_write(&card->controls_rwsem);
Takashi Iwaibb009452014-02-04 18:18:16 +0100379 dev_err(card->dev, "control %i:%i:%i:%s:%i is already present\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 id.iface,
381 id.device,
382 id.subdevice,
383 id.name,
384 id.index);
Takashi Iwaic6077b32006-03-21 16:07:13 +0100385 err = -EBUSY;
386 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 }
388 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
389 up_write(&card->controls_rwsem);
Takashi Iwaic6077b32006-03-21 16:07:13 +0100390 err = -ENOMEM;
391 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 }
393 list_add_tail(&kcontrol->list, &card->controls);
394 card->controls_count += kcontrol->count;
395 kcontrol->id.numid = card->last_numid + 1;
396 card->last_numid += kcontrol->count;
Takashi Sakamotod34890c2015-02-08 22:39:44 +0900397 id = kcontrol->id;
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200398 count = kcontrol->count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 up_write(&card->controls_rwsem);
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200400 for (idx = 0; idx < count; idx++, id.index++, id.numid++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
402 return 0;
Takashi Iwaic6077b32006-03-21 16:07:13 +0100403
404 error:
405 snd_ctl_free_one(kcontrol);
406 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200408EXPORT_SYMBOL(snd_ctl_add);
409
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410/**
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000411 * snd_ctl_replace - replace the control instance of the card
412 * @card: the card instance
413 * @kcontrol: the control instance to replace
414 * @add_on_replace: add the control if not already added
415 *
416 * Replaces the given control. If the given control does not exist
417 * and the add_on_replace flag is set, the control is added. If the
418 * control exists, it is destroyed first.
419 *
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000420 * It frees automatically the control which cannot be added or replaced.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100421 *
422 * Return: Zero if successful, or a negative error code on failure.
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000423 */
424int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol,
425 bool add_on_replace)
426{
427 struct snd_ctl_elem_id id;
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200428 unsigned int count;
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000429 unsigned int idx;
430 struct snd_kcontrol *old;
431 int ret;
432
433 if (!kcontrol)
434 return -EINVAL;
435 if (snd_BUG_ON(!card || !kcontrol->info)) {
436 ret = -EINVAL;
437 goto error;
438 }
439 id = kcontrol->id;
440 down_write(&card->controls_rwsem);
441 old = snd_ctl_find_id(card, &id);
442 if (!old) {
443 if (add_on_replace)
444 goto add;
445 up_write(&card->controls_rwsem);
446 ret = -EINVAL;
447 goto error;
448 }
449 ret = snd_ctl_remove(card, old);
450 if (ret < 0) {
451 up_write(&card->controls_rwsem);
452 goto error;
453 }
454add:
455 if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
456 up_write(&card->controls_rwsem);
457 ret = -ENOMEM;
458 goto error;
459 }
460 list_add_tail(&kcontrol->list, &card->controls);
461 card->controls_count += kcontrol->count;
462 kcontrol->id.numid = card->last_numid + 1;
463 card->last_numid += kcontrol->count;
Takashi Sakamotoe6ff3842015-02-10 00:01:45 +0900464 id = kcontrol->id;
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200465 count = kcontrol->count;
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000466 up_write(&card->controls_rwsem);
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200467 for (idx = 0; idx < count; idx++, id.index++, id.numid++)
Dimitris Papastamos66b5b972011-03-16 12:16:39 +0000468 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
469 return 0;
470
471error:
472 snd_ctl_free_one(kcontrol);
473 return ret;
474}
475EXPORT_SYMBOL(snd_ctl_replace);
476
477/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478 * snd_ctl_remove - remove the control from the card and release it
479 * @card: the card instance
480 * @kcontrol: the control instance to remove
481 *
482 * Removes the control from the card and then releases the instance.
483 * You don't need to call snd_ctl_free_one(). You must be in
484 * the write lock - down_write(&card->controls_rwsem).
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100485 *
486 * Return: 0 if successful, or a negative error code on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100488int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100490 struct snd_ctl_elem_id id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 unsigned int idx;
492
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200493 if (snd_BUG_ON(!card || !kcontrol))
494 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 list_del(&kcontrol->list);
496 card->controls_count -= kcontrol->count;
497 id = kcontrol->id;
498 for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
499 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
500 snd_ctl_free_one(kcontrol);
501 return 0;
502}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200503EXPORT_SYMBOL(snd_ctl_remove);
504
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505/**
506 * snd_ctl_remove_id - remove the control of the given id and release it
507 * @card: the card instance
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 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100515int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100517 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 int ret;
519
520 down_write(&card->controls_rwsem);
521 kctl = snd_ctl_find_id(card, id);
522 if (kctl == NULL) {
523 up_write(&card->controls_rwsem);
524 return -ENOENT;
525 }
526 ret = snd_ctl_remove(card, kctl);
527 up_write(&card->controls_rwsem);
528 return ret;
529}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200530EXPORT_SYMBOL(snd_ctl_remove_id);
531
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532/**
Clemens Ladischf217ac52009-08-17 12:27:22 +0200533 * snd_ctl_remove_user_ctl - remove and release the unlocked user control
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534 * @file: active control handle
535 * @id: the control id to remove
536 *
537 * Finds the control instance with the given id, removes it from the
538 * card list and releases it.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100539 *
540 * Return: 0 if successful, or a negative error code on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 */
Clemens Ladischf217ac52009-08-17 12:27:22 +0200542static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
543 struct snd_ctl_elem_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100545 struct snd_card *card = file->card;
546 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 int idx, ret;
548
549 down_write(&card->controls_rwsem);
550 kctl = snd_ctl_find_id(card, id);
551 if (kctl == NULL) {
Clemens Ladisch317b8082009-08-17 12:26:34 +0200552 ret = -ENOENT;
553 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 }
Clemens Ladisch18dd0aa2009-08-17 12:28:09 +0200555 if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
556 ret = -EINVAL;
557 goto error;
558 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559 for (idx = 0; idx < kctl->count; idx++)
560 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
Clemens Ladisch317b8082009-08-17 12:26:34 +0200561 ret = -EBUSY;
562 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563 }
564 ret = snd_ctl_remove(card, kctl);
Clemens Ladischf217ac52009-08-17 12:27:22 +0200565 if (ret < 0)
566 goto error;
567 card->user_ctl_count--;
Clemens Ladisch317b8082009-08-17 12:26:34 +0200568error:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569 up_write(&card->controls_rwsem);
570 return ret;
571}
572
573/**
Takashi Iwai3cbdd752008-08-29 16:09:01 +0200574 * snd_ctl_activate_id - activate/inactivate the control of the given id
575 * @card: the card instance
576 * @id: the control id to activate/inactivate
577 * @active: non-zero to activate
578 *
579 * Finds the control instance with the given id, and activate or
580 * inactivate the control together with notification, if changed.
Takashi Sakamotoc78497e2015-04-11 17:41:02 +0900581 * The given ID data is filled with full information.
Takashi Iwai3cbdd752008-08-29 16:09:01 +0200582 *
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100583 * Return: 0 if unchanged, 1 if changed, or a negative error code on failure.
Takashi Iwai3cbdd752008-08-29 16:09:01 +0200584 */
585int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
586 int active)
587{
588 struct snd_kcontrol *kctl;
589 struct snd_kcontrol_volatile *vd;
590 unsigned int index_offset;
591 int ret;
592
593 down_write(&card->controls_rwsem);
594 kctl = snd_ctl_find_id(card, id);
595 if (kctl == NULL) {
596 ret = -ENOENT;
597 goto unlock;
598 }
Lars-Peter Clausen31584ed2014-11-07 14:12:34 +0100599 index_offset = snd_ctl_get_ioff(kctl, id);
Takashi Iwai3cbdd752008-08-29 16:09:01 +0200600 vd = &kctl->vd[index_offset];
601 ret = 0;
602 if (active) {
603 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE))
604 goto unlock;
605 vd->access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
606 } else {
607 if (vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE)
608 goto unlock;
609 vd->access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE;
610 }
Takashi Sakamotoc78497e2015-04-11 17:41:02 +0900611 snd_ctl_build_ioff(id, kctl, index_offset);
Takashi Iwai3cbdd752008-08-29 16:09:01 +0200612 ret = 1;
613 unlock:
614 up_write(&card->controls_rwsem);
615 if (ret > 0)
616 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, id);
617 return ret;
618}
619EXPORT_SYMBOL_GPL(snd_ctl_activate_id);
620
621/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 * snd_ctl_rename_id - replace the id of a control on the card
623 * @card: the card instance
624 * @src_id: the old id
625 * @dst_id: the new id
626 *
627 * Finds the control with the old id from the card, and replaces the
628 * id with the new one.
629 *
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100630 * Return: Zero if successful, or a negative error code on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100632int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
633 struct snd_ctl_elem_id *dst_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100635 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636
637 down_write(&card->controls_rwsem);
638 kctl = snd_ctl_find_id(card, src_id);
639 if (kctl == NULL) {
640 up_write(&card->controls_rwsem);
641 return -ENOENT;
642 }
643 kctl->id = *dst_id;
644 kctl->id.numid = card->last_numid + 1;
645 card->last_numid += kctl->count;
646 up_write(&card->controls_rwsem);
647 return 0;
648}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200649EXPORT_SYMBOL(snd_ctl_rename_id);
650
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651/**
652 * snd_ctl_find_numid - find the control instance with the given number-id
653 * @card: the card instance
654 * @numid: the number-id to search
655 *
656 * Finds the control instance with the given number-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_numid(struct snd_card *card, unsigned int numid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100666 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200668 if (snd_BUG_ON(!card || !numid))
669 return NULL;
Johannes Berg9244b2c2006-10-05 16:02:22 +0200670 list_for_each_entry(kctl, &card->controls, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
672 return kctl;
673 }
674 return NULL;
675}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200676EXPORT_SYMBOL(snd_ctl_find_numid);
677
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678/**
679 * snd_ctl_find_id - find the control instance with the given id
680 * @card: the card instance
681 * @id: the id to search
682 *
683 * Finds the control instance with the given id from the card.
684 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685 * The caller must down card->controls_rwsem before calling this function
686 * (if the race condition can happen).
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100687 *
688 * Return: The pointer of the instance if found, or %NULL if not.
689 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100691struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
692 struct snd_ctl_elem_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100694 struct snd_kcontrol *kctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200696 if (snd_BUG_ON(!card || !id))
697 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 if (id->numid != 0)
699 return snd_ctl_find_numid(card, id->numid);
Johannes Berg9244b2c2006-10-05 16:02:22 +0200700 list_for_each_entry(kctl, &card->controls, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 if (kctl->id.iface != id->iface)
702 continue;
703 if (kctl->id.device != id->device)
704 continue;
705 if (kctl->id.subdevice != id->subdevice)
706 continue;
707 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
708 continue;
709 if (kctl->id.index > id->index)
710 continue;
711 if (kctl->id.index + kctl->count <= id->index)
712 continue;
713 return kctl;
714 }
715 return NULL;
716}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +0200717EXPORT_SYMBOL(snd_ctl_find_id);
718
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100719static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720 unsigned int cmd, void __user *arg)
721{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100722 struct snd_ctl_card_info *info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723
Takashi Iwaica2c0962005-09-09 14:20:23 +0200724 info = kzalloc(sizeof(*info), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 if (! info)
726 return -ENOMEM;
727 down_read(&snd_ioctl_rwsem);
728 info->card = card->number;
729 strlcpy(info->id, card->id, sizeof(info->id));
730 strlcpy(info->driver, card->driver, sizeof(info->driver));
731 strlcpy(info->name, card->shortname, sizeof(info->name));
732 strlcpy(info->longname, card->longname, sizeof(info->longname));
733 strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
734 strlcpy(info->components, card->components, sizeof(info->components));
735 up_read(&snd_ioctl_rwsem);
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100736 if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737 kfree(info);
738 return -EFAULT;
739 }
740 kfree(info);
741 return 0;
742}
743
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100744static int snd_ctl_elem_list(struct snd_card *card,
745 struct snd_ctl_elem_list __user *_list)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746{
747 struct list_head *plist;
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100748 struct snd_ctl_elem_list list;
749 struct snd_kcontrol *kctl;
750 struct snd_ctl_elem_id *dst, *id;
Luca Tettamanti78fa2c42011-05-25 22:43:27 +0200751 unsigned int offset, space, jidx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752
753 if (copy_from_user(&list, _list, sizeof(list)))
754 return -EFAULT;
755 offset = list.offset;
756 space = list.space;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 /* try limit maximum space */
758 if (space > 16384)
759 return -ENOMEM;
760 if (space > 0) {
761 /* allocate temporary buffer for atomic operation */
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100762 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763 if (dst == NULL)
764 return -ENOMEM;
765 down_read(&card->controls_rwsem);
766 list.count = card->controls_count;
767 plist = card->controls.next;
768 while (plist != &card->controls) {
769 if (offset == 0)
770 break;
771 kctl = snd_kcontrol(plist);
772 if (offset < kctl->count)
773 break;
774 offset -= kctl->count;
775 plist = plist->next;
776 }
777 list.used = 0;
778 id = dst;
779 while (space > 0 && plist != &card->controls) {
780 kctl = snd_kcontrol(plist);
781 for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
782 snd_ctl_build_ioff(id, kctl, jidx);
783 id++;
784 space--;
785 list.used++;
786 }
787 plist = plist->next;
788 offset = 0;
789 }
790 up_read(&card->controls_rwsem);
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100791 if (list.used > 0 &&
792 copy_to_user(list.pids, dst,
793 list.used * sizeof(struct snd_ctl_elem_id))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 vfree(dst);
795 return -EFAULT;
796 }
797 vfree(dst);
798 } else {
799 down_read(&card->controls_rwsem);
800 list.count = card->controls_count;
801 up_read(&card->controls_rwsem);
802 }
803 if (copy_to_user(_list, &list, sizeof(list)))
804 return -EFAULT;
805 return 0;
806}
807
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100808static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
809 struct snd_ctl_elem_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100811 struct snd_card *card = ctl->card;
812 struct snd_kcontrol *kctl;
813 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814 unsigned int index_offset;
815 int result;
816
817 down_read(&card->controls_rwsem);
818 kctl = snd_ctl_find_id(card, &info->id);
819 if (kctl == NULL) {
820 up_read(&card->controls_rwsem);
821 return -ENOENT;
822 }
823#ifdef CONFIG_SND_DEBUG
824 info->access = 0;
825#endif
826 result = kctl->info(kctl, info);
827 if (result >= 0) {
Takashi Iwai7eaa9432008-08-08 17:09:09 +0200828 snd_BUG_ON(info->access);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829 index_offset = snd_ctl_get_ioff(kctl, &info->id);
830 vd = &kctl->vd[index_offset];
831 snd_ctl_build_ioff(&info->id, kctl, index_offset);
832 info->access = vd->access;
833 if (vd->owner) {
834 info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
835 if (vd->owner == ctl)
836 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
Clemens Ladisch25d27ed2009-11-02 09:35:44 +0100837 info->owner = pid_vnr(vd->owner->pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 } else {
839 info->owner = -1;
840 }
841 }
842 up_read(&card->controls_rwsem);
843 return result;
844}
845
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100846static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
847 struct snd_ctl_elem_info __user *_info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100849 struct snd_ctl_elem_info info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850 int result;
851
852 if (copy_from_user(&info, _info, sizeof(info)))
853 return -EFAULT;
Giuliano Pochini64649402006-03-13 14:11:11 +0100854 snd_power_lock(ctl->card);
Takashi Iwaicbac4b02006-03-27 12:38:07 +0200855 result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
Giuliano Pochini64649402006-03-13 14:11:11 +0100856 if (result >= 0)
857 result = snd_ctl_elem_info(ctl, &info);
858 snd_power_unlock(ctl->card);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859 if (result >= 0)
860 if (copy_to_user(_info, &info, sizeof(info)))
861 return -EFAULT;
862 return result;
863}
864
Takashi Iwaid3bd67c2008-06-12 18:17:26 +0200865static int snd_ctl_elem_read(struct snd_card *card,
866 struct snd_ctl_elem_value *control)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100868 struct snd_kcontrol *kctl;
869 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 unsigned int index_offset;
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100871 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872
873 down_read(&card->controls_rwsem);
874 kctl = snd_ctl_find_id(card, &control->id);
875 if (kctl == NULL) {
876 result = -ENOENT;
877 } else {
878 index_offset = snd_ctl_get_ioff(kctl, &control->id);
879 vd = &kctl->vd[index_offset];
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100880 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
881 kctl->get != NULL) {
882 snd_ctl_build_ioff(&control->id, kctl, index_offset);
883 result = kctl->get(kctl, control);
884 } else
885 result = -EPERM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886 }
887 up_read(&card->controls_rwsem);
888 return result;
889}
890
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100891static int snd_ctl_elem_read_user(struct snd_card *card,
892 struct snd_ctl_elem_value __user *_control)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100894 struct snd_ctl_elem_value *control;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 int result;
Li Zefanef44a1e2009-04-10 09:43:08 +0800896
897 control = memdup_user(_control, sizeof(*control));
898 if (IS_ERR(control))
899 return PTR_ERR(control);
900
Giuliano Pochini64649402006-03-13 14:11:11 +0100901 snd_power_lock(card);
Takashi Iwaicbac4b02006-03-27 12:38:07 +0200902 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
Giuliano Pochini64649402006-03-13 14:11:11 +0100903 if (result >= 0)
904 result = snd_ctl_elem_read(card, control);
905 snd_power_unlock(card);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906 if (result >= 0)
907 if (copy_to_user(_control, control, sizeof(*control)))
908 result = -EFAULT;
909 kfree(control);
910 return result;
911}
912
Takashi Iwaid3bd67c2008-06-12 18:17:26 +0200913static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
914 struct snd_ctl_elem_value *control)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100916 struct snd_kcontrol *kctl;
917 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 unsigned int index_offset;
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100919 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920
921 down_read(&card->controls_rwsem);
922 kctl = snd_ctl_find_id(card, &control->id);
923 if (kctl == NULL) {
924 result = -ENOENT;
925 } else {
926 index_offset = snd_ctl_get_ioff(kctl, &control->id);
927 vd = &kctl->vd[index_offset];
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100928 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
929 kctl->put == NULL ||
930 (file && vd->owner && vd->owner != file)) {
931 result = -EPERM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932 } else {
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100933 snd_ctl_build_ioff(&control->id, kctl, index_offset);
934 result = kctl->put(kctl, control);
935 }
936 if (result > 0) {
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200937 struct snd_ctl_elem_id id = control->id;
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100938 up_read(&card->controls_rwsem);
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +0200939 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, &id);
Takashi Iwai8ace4f32008-01-08 17:57:26 +0100940 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700941 }
942 }
943 up_read(&card->controls_rwsem);
944 return result;
945}
946
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100947static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
948 struct snd_ctl_elem_value __user *_control)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100950 struct snd_ctl_elem_value *control;
Giuliano Pochini64649402006-03-13 14:11:11 +0100951 struct snd_card *card;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952 int result;
953
Li Zefanef44a1e2009-04-10 09:43:08 +0800954 control = memdup_user(_control, sizeof(*control));
955 if (IS_ERR(control))
956 return PTR_ERR(control);
957
Giuliano Pochini64649402006-03-13 14:11:11 +0100958 card = file->card;
959 snd_power_lock(card);
Takashi Iwaicbac4b02006-03-27 12:38:07 +0200960 result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
Giuliano Pochini64649402006-03-13 14:11:11 +0100961 if (result >= 0)
962 result = snd_ctl_elem_write(card, file, control);
963 snd_power_unlock(card);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964 if (result >= 0)
965 if (copy_to_user(_control, control, sizeof(*control)))
966 result = -EFAULT;
967 kfree(control);
968 return result;
969}
970
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100971static int snd_ctl_elem_lock(struct snd_ctl_file *file,
972 struct snd_ctl_elem_id __user *_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700973{
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100974 struct snd_card *card = file->card;
975 struct snd_ctl_elem_id id;
976 struct snd_kcontrol *kctl;
977 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978 int result;
979
980 if (copy_from_user(&id, _id, sizeof(id)))
981 return -EFAULT;
982 down_write(&card->controls_rwsem);
983 kctl = snd_ctl_find_id(card, &id);
984 if (kctl == NULL) {
985 result = -ENOENT;
986 } else {
987 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
988 if (vd->owner != NULL)
989 result = -EBUSY;
990 else {
991 vd->owner = file;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992 result = 0;
993 }
994 }
995 up_write(&card->controls_rwsem);
996 return result;
997}
998
Takashi Iwai82e9bae2005-11-17 13:53:23 +0100999static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
1000 struct snd_ctl_elem_id __user *_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001002 struct snd_card *card = file->card;
1003 struct snd_ctl_elem_id id;
1004 struct snd_kcontrol *kctl;
1005 struct snd_kcontrol_volatile *vd;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 int result;
1007
1008 if (copy_from_user(&id, _id, sizeof(id)))
1009 return -EFAULT;
1010 down_write(&card->controls_rwsem);
1011 kctl = snd_ctl_find_id(card, &id);
1012 if (kctl == NULL) {
1013 result = -ENOENT;
1014 } else {
1015 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
1016 if (vd->owner == NULL)
1017 result = -EINVAL;
1018 else if (vd->owner != file)
1019 result = -EPERM;
1020 else {
1021 vd->owner = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001022 result = 0;
1023 }
1024 }
1025 up_write(&card->controls_rwsem);
1026 return result;
1027}
1028
1029struct user_element {
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001030 struct snd_ctl_elem_info info;
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001031 struct snd_card *card;
Takashi Sakamotoe1c78df2015-04-12 10:12:25 +09001032 char *elem_data; /* element data */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033 unsigned long elem_data_size; /* size of element data in bytes */
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001034 void *tlv_data; /* TLV data */
1035 unsigned long tlv_data_size; /* TLV data size */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001036 void *priv_data; /* private data (like strings for enumerated type) */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001037};
1038
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001039static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
1040 struct snd_ctl_elem_info *uinfo)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001041{
1042 struct user_element *ue = kcontrol->private_data;
Takashi Sakamotoc378c3b2015-04-11 17:41:03 +09001043 unsigned int offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001044
Takashi Sakamotoc378c3b2015-04-11 17:41:03 +09001045 offset = snd_ctl_get_ioff(kcontrol, &uinfo->id);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046 *uinfo = ue->info;
Takashi Sakamotoc378c3b2015-04-11 17:41:03 +09001047 snd_ctl_build_ioff(&uinfo->id, kcontrol, offset);
1048
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049 return 0;
1050}
1051
Clemens Ladisch8d448162011-10-07 22:38:59 +02001052static int snd_ctl_elem_user_enum_info(struct snd_kcontrol *kcontrol,
1053 struct snd_ctl_elem_info *uinfo)
1054{
1055 struct user_element *ue = kcontrol->private_data;
1056 const char *names;
1057 unsigned int item;
Takashi Sakamotoc378c3b2015-04-11 17:41:03 +09001058 unsigned int offset;
Clemens Ladisch8d448162011-10-07 22:38:59 +02001059
1060 item = uinfo->value.enumerated.item;
1061
Takashi Sakamotoc378c3b2015-04-11 17:41:03 +09001062 offset = snd_ctl_get_ioff(kcontrol, &uinfo->id);
Clemens Ladisch8d448162011-10-07 22:38:59 +02001063 *uinfo = ue->info;
Takashi Sakamotoc378c3b2015-04-11 17:41:03 +09001064 snd_ctl_build_ioff(&uinfo->id, kcontrol, offset);
Clemens Ladisch8d448162011-10-07 22:38:59 +02001065
1066 item = min(item, uinfo->value.enumerated.items - 1);
1067 uinfo->value.enumerated.item = item;
1068
1069 names = ue->priv_data;
1070 for (; item > 0; --item)
1071 names += strlen(names) + 1;
1072 strcpy(uinfo->value.enumerated.name, names);
1073
1074 return 0;
1075}
1076
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001077static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
1078 struct snd_ctl_elem_value *ucontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001079{
1080 struct user_element *ue = kcontrol->private_data;
Takashi Sakamotoe1c78df2015-04-12 10:12:25 +09001081 unsigned int size = ue->elem_data_size;
1082 char *src = ue->elem_data +
1083 snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001084
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001085 mutex_lock(&ue->card->user_ctl_lock);
Takashi Sakamotoe1c78df2015-04-12 10:12:25 +09001086 memcpy(&ucontrol->value, src, size);
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001087 mutex_unlock(&ue->card->user_ctl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001088 return 0;
1089}
1090
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001091static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
1092 struct snd_ctl_elem_value *ucontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093{
1094 int change;
1095 struct user_element *ue = kcontrol->private_data;
Takashi Sakamotoe1c78df2015-04-12 10:12:25 +09001096 unsigned int size = ue->elem_data_size;
1097 char *dst = ue->elem_data +
1098 snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size;
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001099
1100 mutex_lock(&ue->card->user_ctl_lock);
Takashi Sakamotoe1c78df2015-04-12 10:12:25 +09001101 change = memcmp(&ucontrol->value, dst, size) != 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102 if (change)
Takashi Sakamotoe1c78df2015-04-12 10:12:25 +09001103 memcpy(dst, &ucontrol->value, size);
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001104 mutex_unlock(&ue->card->user_ctl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001105 return change;
1106}
1107
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001108static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
1109 int op_flag,
1110 unsigned int size,
1111 unsigned int __user *tlv)
1112{
1113 struct user_element *ue = kcontrol->private_data;
1114 int change = 0;
1115 void *new_data;
1116
Takashi Sakamoto39d11862015-04-10 08:43:00 +09001117 if (op_flag == SNDRV_CTL_TLV_OP_WRITE) {
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001118 if (size > 1024 * 128) /* sane value */
1119 return -EINVAL;
Li Zefanef44a1e2009-04-10 09:43:08 +08001120
1121 new_data = memdup_user(tlv, size);
1122 if (IS_ERR(new_data))
1123 return PTR_ERR(new_data);
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001124 mutex_lock(&ue->card->user_ctl_lock);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001125 change = ue->tlv_data_size != size;
1126 if (!change)
1127 change = memcmp(ue->tlv_data, new_data, size);
1128 kfree(ue->tlv_data);
1129 ue->tlv_data = new_data;
1130 ue->tlv_data_size = size;
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001131 mutex_unlock(&ue->card->user_ctl_lock);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001132 } else {
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001133 int ret = 0;
1134
1135 mutex_lock(&ue->card->user_ctl_lock);
1136 if (!ue->tlv_data_size || !ue->tlv_data) {
1137 ret = -ENXIO;
1138 goto err_unlock;
1139 }
1140 if (size < ue->tlv_data_size) {
1141 ret = -ENOSPC;
1142 goto err_unlock;
1143 }
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001144 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001145 ret = -EFAULT;
1146err_unlock:
1147 mutex_unlock(&ue->card->user_ctl_lock);
1148 if (ret)
1149 return ret;
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001150 }
1151 return change;
1152}
1153
Clemens Ladisch8d448162011-10-07 22:38:59 +02001154static int snd_ctl_elem_init_enum_names(struct user_element *ue)
1155{
1156 char *names, *p;
1157 size_t buf_len, name_len;
1158 unsigned int i;
Olof Johansson447c6f92011-11-05 22:51:54 +01001159 const uintptr_t user_ptrval = ue->info.value.enumerated.names_ptr;
Clemens Ladisch8d448162011-10-07 22:38:59 +02001160
1161 if (ue->info.value.enumerated.names_length > 64 * 1024)
1162 return -EINVAL;
1163
Olof Johansson447c6f92011-11-05 22:51:54 +01001164 names = memdup_user((const void __user *)user_ptrval,
Clemens Ladisch8d448162011-10-07 22:38:59 +02001165 ue->info.value.enumerated.names_length);
1166 if (IS_ERR(names))
1167 return PTR_ERR(names);
1168
1169 /* check that there are enough valid names */
1170 buf_len = ue->info.value.enumerated.names_length;
1171 p = names;
1172 for (i = 0; i < ue->info.value.enumerated.items; ++i) {
1173 name_len = strnlen(p, buf_len);
1174 if (name_len == 0 || name_len >= 64 || name_len == buf_len) {
1175 kfree(names);
1176 return -EINVAL;
1177 }
1178 p += name_len + 1;
1179 buf_len -= name_len + 1;
1180 }
1181
1182 ue->priv_data = names;
1183 ue->info.value.enumerated.names_ptr = 0;
1184
1185 return 0;
1186}
1187
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001188static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001189{
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001190 struct user_element *ue = kcontrol->private_data;
Clemens Ladisch8d448162011-10-07 22:38:59 +02001191
1192 kfree(ue->tlv_data);
1193 kfree(ue->priv_data);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001194 kfree(ue);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001195}
1196
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001197static int snd_ctl_elem_add(struct snd_ctl_file *file,
1198 struct snd_ctl_elem_info *info, int replace)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001199{
Takashi Sakamoto4ed56662015-03-10 22:13:30 +09001200 /* The capacity of struct snd_ctl_elem_value.value.*/
1201 static const unsigned int value_sizes[] = {
1202 [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = sizeof(long),
1203 [SNDRV_CTL_ELEM_TYPE_INTEGER] = sizeof(long),
1204 [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = sizeof(unsigned int),
1205 [SNDRV_CTL_ELEM_TYPE_BYTES] = sizeof(unsigned char),
1206 [SNDRV_CTL_ELEM_TYPE_IEC958] = sizeof(struct snd_aes_iec958),
1207 [SNDRV_CTL_ELEM_TYPE_INTEGER64] = sizeof(long long),
1208 };
1209 static const unsigned int max_value_counts[] = {
1210 [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = 128,
1211 [SNDRV_CTL_ELEM_TYPE_INTEGER] = 128,
1212 [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = 128,
1213 [SNDRV_CTL_ELEM_TYPE_BYTES] = 512,
1214 [SNDRV_CTL_ELEM_TYPE_IEC958] = 1,
1215 [SNDRV_CTL_ELEM_TYPE_INTEGER64] = 64,
1216 };
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001217 struct snd_card *card = file->card;
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001218 struct snd_kcontrol *kctl;
1219 unsigned int count;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001220 unsigned int access;
1221 long private_size;
1222 struct user_element *ue;
Takashi Sakamotocab2ed72015-04-11 17:41:04 +09001223 unsigned int offset;
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001224 int err;
Lu Guanqun983929c2011-08-24 11:12:34 +08001225
Takashi Iwaibe3bb822015-03-11 18:12:49 +01001226 if (!*info->id.name)
1227 return -EINVAL;
1228 if (strnlen(info->id.name, sizeof(info->id.name)) >= sizeof(info->id.name))
1229 return -EINVAL;
Lars-Peter Clausen82262a462014-06-18 13:32:32 +02001230
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001231 /* Delete a control to replace them if needed. */
Lars-Peter Clausen82262a462014-06-18 13:32:32 +02001232 if (replace) {
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001233 info->id.numid = 0;
Lars-Peter Clausen82262a462014-06-18 13:32:32 +02001234 err = snd_ctl_remove_user_ctl(file, &info->id);
1235 if (err)
1236 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001237 }
Lars-Peter Clausen82262a462014-06-18 13:32:32 +02001238
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001239 /*
1240 * The number of userspace controls are counted control by control,
1241 * not element by element.
1242 */
1243 if (card->user_ctl_count + 1 > MAX_USER_CONTROLS)
Lars-Peter Clausen82262a462014-06-18 13:32:32 +02001244 return -ENOMEM;
1245
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001246 /* Check the number of elements for this userspace control. */
1247 count = info->owner;
1248 if (count == 0)
1249 count = 1;
Takashi Sakamoto4ed56662015-03-10 22:13:30 +09001250
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001251 /* Arrange access permissions if needed. */
1252 access = info->access;
1253 if (access == 0)
1254 access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
1255 access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE |
1256 SNDRV_CTL_ELEM_ACCESS_INACTIVE |
1257 SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE);
1258 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE)
1259 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1260 access |= SNDRV_CTL_ELEM_ACCESS_USER;
1261
1262 /*
1263 * Check information and calculate the size of data specific to
1264 * this userspace control.
1265 */
Takashi Sakamoto4ed56662015-03-10 22:13:30 +09001266 if (info->type < SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
1267 info->type > SNDRV_CTL_ELEM_TYPE_INTEGER64)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001268 return -EINVAL;
Takashi Sakamoto4ed56662015-03-10 22:13:30 +09001269 if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED &&
1270 info->value.enumerated.items == 0)
1271 return -EINVAL;
1272 if (info->count < 1 ||
1273 info->count > max_value_counts[info->type])
1274 return -EINVAL;
Takashi Sakamoto4ed56662015-03-10 22:13:30 +09001275 private_size = value_sizes[info->type] * info->count;
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001276
1277 /*
1278 * Keep memory object for this userspace control. After passing this
1279 * code block, the instance should be freed by snd_ctl_free_one().
1280 *
1281 * Note that these elements in this control are locked.
1282 */
1283 err = snd_ctl_new(&kctl, count, access, file);
1284 if (err < 0)
1285 return err;
Takashi Iwaie79d74a2015-03-12 16:57:51 +01001286 memcpy(&kctl->id, &info->id, sizeof(kctl->id));
Takashi Sakamotoe1c78df2015-04-12 10:12:25 +09001287 kctl->private_data = kzalloc(sizeof(struct user_element) + private_size * count,
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001288 GFP_KERNEL);
1289 if (kctl->private_data == NULL) {
1290 kfree(kctl);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001291 return -ENOMEM;
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001292 }
1293 kctl->private_free = snd_ctl_elem_user_free;
1294
1295 /* Set private data for this userspace control. */
1296 ue = (struct user_element *)kctl->private_data;
Lars-Peter Clausen07f4d9d2014-06-18 13:32:31 +02001297 ue->card = card;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001298 ue->info = *info;
Takashi Iwai86148e82006-08-24 12:36:36 +02001299 ue->info.access = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001300 ue->elem_data = (char *)ue + sizeof(*ue);
1301 ue->elem_data_size = private_size;
Clemens Ladisch8d448162011-10-07 22:38:59 +02001302 if (ue->info.type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) {
1303 err = snd_ctl_elem_init_enum_names(ue);
1304 if (err < 0) {
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001305 snd_ctl_free_one(kctl);
Clemens Ladisch8d448162011-10-07 22:38:59 +02001306 return err;
1307 }
1308 }
Takashi Sakamoto2225e792015-03-10 22:13:31 +09001309
1310 /* Set callback functions. */
1311 if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED)
1312 kctl->info = snd_ctl_elem_user_enum_info;
1313 else
1314 kctl->info = snd_ctl_elem_user_info;
1315 if (access & SNDRV_CTL_ELEM_ACCESS_READ)
1316 kctl->get = snd_ctl_elem_user_get;
1317 if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
1318 kctl->put = snd_ctl_elem_user_put;
1319 if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE)
1320 kctl->tlv.c = snd_ctl_elem_user_tlv;
1321
1322 /* This function manage to free the instance on failure. */
1323 err = snd_ctl_add(card, kctl);
Takashi Iwai2fbf1822006-03-06 15:42:51 -08001324 if (err < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001325 return err;
Takashi Sakamotocab2ed72015-04-11 17:41:04 +09001326 offset = snd_ctl_get_ioff(kctl, &info->id);
1327 snd_ctl_build_ioff(&info->id, kctl, offset);
1328 /*
1329 * Here we cannot fill any field for the number of elements added by
1330 * this operation because there're no specific fields. The usage of
1331 * 'owner' field for this purpose may cause any bugs to userspace
1332 * applications because the field originally means PID of a process
1333 * which locks the element.
1334 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001335
1336 down_write(&card->controls_rwsem);
1337 card->user_ctl_count++;
1338 up_write(&card->controls_rwsem);
1339
1340 return 0;
1341}
1342
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001343static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1344 struct snd_ctl_elem_info __user *_info, int replace)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001345{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001346 struct snd_ctl_elem_info info;
Takashi Sakamotocab2ed72015-04-11 17:41:04 +09001347 int err;
1348
Linus Torvalds1da177e2005-04-16 15:20:36 -07001349 if (copy_from_user(&info, _info, sizeof(info)))
1350 return -EFAULT;
Takashi Sakamotocab2ed72015-04-11 17:41:04 +09001351 err = snd_ctl_elem_add(file, &info, replace);
1352 if (err < 0)
1353 return err;
1354 if (copy_to_user(_info, &info, sizeof(info))) {
1355 snd_ctl_remove_user_ctl(file, &info.id);
1356 return -EFAULT;
1357 }
1358
1359 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360}
1361
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001362static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1363 struct snd_ctl_elem_id __user *_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001364{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001365 struct snd_ctl_elem_id id;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001366
1367 if (copy_from_user(&id, _id, sizeof(id)))
1368 return -EFAULT;
Clemens Ladischf217ac52009-08-17 12:27:22 +02001369 return snd_ctl_remove_user_ctl(file, &id);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370}
1371
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001372static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373{
1374 int subscribe;
1375 if (get_user(subscribe, ptr))
1376 return -EFAULT;
1377 if (subscribe < 0) {
1378 subscribe = file->subscribed;
1379 if (put_user(subscribe, ptr))
1380 return -EFAULT;
1381 return 0;
1382 }
1383 if (subscribe) {
1384 file->subscribed = 1;
1385 return 0;
1386 } else if (file->subscribed) {
1387 snd_ctl_empty_read_queue(file);
1388 file->subscribed = 0;
1389 }
1390 return 0;
1391}
1392
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001393static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1394 struct snd_ctl_tlv __user *_tlv,
1395 int op_flag)
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001396{
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001397 struct snd_card *card = file->card;
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001398 struct snd_ctl_tlv tlv;
1399 struct snd_kcontrol *kctl;
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001400 struct snd_kcontrol_volatile *vd;
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001401 unsigned int len;
1402 int err = 0;
1403
1404 if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1405 return -EFAULT;
Clemens Ladisch61236372010-02-01 13:30:56 +01001406 if (tlv.length < sizeof(unsigned int) * 2)
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001407 return -EINVAL;
Takashi Iwaic0bcdbd2016-01-18 14:12:40 +01001408 if (!tlv.numid)
1409 return -EINVAL;
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001410 down_read(&card->controls_rwsem);
1411 kctl = snd_ctl_find_numid(card, tlv.numid);
1412 if (kctl == NULL) {
1413 err = -ENOENT;
1414 goto __kctl_end;
1415 }
1416 if (kctl->tlv.p == NULL) {
1417 err = -ENXIO;
1418 goto __kctl_end;
1419 }
1420 vd = &kctl->vd[tlv.numid - kctl->id.numid];
Takashi Sakamoto39d11862015-04-10 08:43:00 +09001421 if ((op_flag == SNDRV_CTL_TLV_OP_READ &&
1422 (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1423 (op_flag == SNDRV_CTL_TLV_OP_WRITE &&
1424 (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1425 (op_flag == SNDRV_CTL_TLV_OP_CMD &&
1426 (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001427 err = -ENXIO;
1428 goto __kctl_end;
1429 }
1430 if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
Dan Carpenterbec145a2009-11-18 10:31:57 +02001431 if (vd->owner != NULL && vd->owner != file) {
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001432 err = -EPERM;
1433 goto __kctl_end;
1434 }
Jeffrin Josebd483d42012-03-07 22:57:39 +05301435 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001436 if (err > 0) {
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +02001437 struct snd_ctl_elem_id id = kctl->id;
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001438 up_read(&card->controls_rwsem);
Lars-Peter Clausenfd9f26e2014-06-18 13:32:33 +02001439 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &id);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001440 return 0;
1441 }
1442 } else {
Takashi Iwaic30cf8c2015-04-12 09:16:11 +02001443 if (op_flag != SNDRV_CTL_TLV_OP_READ) {
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001444 err = -ENXIO;
1445 goto __kctl_end;
1446 }
1447 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1448 if (tlv.length < len) {
1449 err = -ENOMEM;
1450 goto __kctl_end;
1451 }
1452 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1453 err = -EFAULT;
1454 }
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001455 __kctl_end:
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001456 up_read(&card->controls_rwsem);
1457 return err;
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001458}
1459
Linus Torvalds1da177e2005-04-16 15:20:36 -07001460static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1461{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001462 struct snd_ctl_file *ctl;
1463 struct snd_card *card;
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001464 struct snd_kctl_ioctl *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001465 void __user *argp = (void __user *)arg;
1466 int __user *ip = argp;
1467 int err;
1468
1469 ctl = file->private_data;
1470 card = ctl->card;
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001471 if (snd_BUG_ON(!card))
1472 return -ENXIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001473 switch (cmd) {
1474 case SNDRV_CTL_IOCTL_PVERSION:
1475 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1476 case SNDRV_CTL_IOCTL_CARD_INFO:
1477 return snd_ctl_card_info(card, ctl, cmd, argp);
1478 case SNDRV_CTL_IOCTL_ELEM_LIST:
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001479 return snd_ctl_elem_list(card, argp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001480 case SNDRV_CTL_IOCTL_ELEM_INFO:
1481 return snd_ctl_elem_info_user(ctl, argp);
1482 case SNDRV_CTL_IOCTL_ELEM_READ:
Jaroslav Kysela42750b02006-06-01 18:34:01 +02001483 return snd_ctl_elem_read_user(card, argp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001484 case SNDRV_CTL_IOCTL_ELEM_WRITE:
1485 return snd_ctl_elem_write_user(ctl, argp);
1486 case SNDRV_CTL_IOCTL_ELEM_LOCK:
1487 return snd_ctl_elem_lock(ctl, argp);
1488 case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1489 return snd_ctl_elem_unlock(ctl, argp);
1490 case SNDRV_CTL_IOCTL_ELEM_ADD:
1491 return snd_ctl_elem_add_user(ctl, argp, 0);
1492 case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1493 return snd_ctl_elem_add_user(ctl, argp, 1);
1494 case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1495 return snd_ctl_elem_remove(ctl, argp);
1496 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1497 return snd_ctl_subscribe_events(ctl, ip);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001498 case SNDRV_CTL_IOCTL_TLV_READ:
Takashi Iwai0cea76f2014-07-15 16:31:01 +02001499 return snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_READ);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001500 case SNDRV_CTL_IOCTL_TLV_WRITE:
Takashi Iwai0cea76f2014-07-15 16:31:01 +02001501 return snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_WRITE);
Jaroslav Kysela8aa9b582006-07-05 17:34:51 +02001502 case SNDRV_CTL_IOCTL_TLV_COMMAND:
Takashi Iwai0cea76f2014-07-15 16:31:01 +02001503 return snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_CMD);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504 case SNDRV_CTL_IOCTL_POWER:
Takashi Iwaia381a7a2005-11-17 15:55:49 +01001505 return -ENOPROTOOPT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001506 case SNDRV_CTL_IOCTL_POWER_STATE:
1507#ifdef CONFIG_PM
1508 return put_user(card->power_state, ip) ? -EFAULT : 0;
1509#else
1510 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1511#endif
1512 }
1513 down_read(&snd_ioctl_rwsem);
Johannes Berg9244b2c2006-10-05 16:02:22 +02001514 list_for_each_entry(p, &snd_control_ioctls, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001515 err = p->fioctl(card, ctl, cmd, arg);
1516 if (err != -ENOIOCTLCMD) {
1517 up_read(&snd_ioctl_rwsem);
1518 return err;
1519 }
1520 }
1521 up_read(&snd_ioctl_rwsem);
Takashi Iwaibb009452014-02-04 18:18:16 +01001522 dev_dbg(card->dev, "unknown ioctl = 0x%x\n", cmd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001523 return -ENOTTY;
1524}
1525
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001526static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1527 size_t count, loff_t * offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001528{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001529 struct snd_ctl_file *ctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530 int err = 0;
1531 ssize_t result = 0;
1532
1533 ctl = file->private_data;
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001534 if (snd_BUG_ON(!ctl || !ctl->card))
1535 return -ENXIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001536 if (!ctl->subscribed)
1537 return -EBADFD;
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001538 if (count < sizeof(struct snd_ctl_event))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001539 return -EINVAL;
1540 spin_lock_irq(&ctl->read_lock);
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001541 while (count >= sizeof(struct snd_ctl_event)) {
1542 struct snd_ctl_event ev;
1543 struct snd_kctl_event *kev;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544 while (list_empty(&ctl->events)) {
1545 wait_queue_t wait;
1546 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1547 err = -EAGAIN;
1548 goto __end_lock;
1549 }
1550 init_waitqueue_entry(&wait, current);
1551 add_wait_queue(&ctl->change_sleep, &wait);
1552 set_current_state(TASK_INTERRUPTIBLE);
1553 spin_unlock_irq(&ctl->read_lock);
1554 schedule();
1555 remove_wait_queue(&ctl->change_sleep, &wait);
Takashi Iwai0914f792012-10-16 16:43:39 +02001556 if (ctl->card->shutdown)
1557 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001558 if (signal_pending(current))
Adrian Bunk0e5d7202006-11-07 13:42:54 +01001559 return -ERESTARTSYS;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001560 spin_lock_irq(&ctl->read_lock);
1561 }
1562 kev = snd_kctl_event(ctl->events.next);
1563 ev.type = SNDRV_CTL_EVENT_ELEM;
1564 ev.data.elem.mask = kev->mask;
1565 ev.data.elem.id = kev->id;
1566 list_del(&kev->list);
1567 spin_unlock_irq(&ctl->read_lock);
1568 kfree(kev);
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001569 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001570 err = -EFAULT;
1571 goto __end;
1572 }
1573 spin_lock_irq(&ctl->read_lock);
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001574 buffer += sizeof(struct snd_ctl_event);
1575 count -= sizeof(struct snd_ctl_event);
1576 result += sizeof(struct snd_ctl_event);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001577 }
1578 __end_lock:
1579 spin_unlock_irq(&ctl->read_lock);
1580 __end:
1581 return result > 0 ? result : err;
1582}
1583
1584static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1585{
1586 unsigned int mask;
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001587 struct snd_ctl_file *ctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001588
1589 ctl = file->private_data;
1590 if (!ctl->subscribed)
1591 return 0;
1592 poll_wait(file, &ctl->change_sleep, wait);
1593
1594 mask = 0;
1595 if (!list_empty(&ctl->events))
1596 mask |= POLLIN | POLLRDNORM;
1597
1598 return mask;
1599}
1600
1601/*
1602 * register the device-specific control-ioctls.
1603 * called from each device manager like pcm.c, hwdep.c, etc.
1604 */
1605static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1606{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001607 struct snd_kctl_ioctl *pn;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001608
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001609 pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001610 if (pn == NULL)
1611 return -ENOMEM;
1612 pn->fioctl = fcn;
1613 down_write(&snd_ioctl_rwsem);
1614 list_add_tail(&pn->list, lists);
1615 up_write(&snd_ioctl_rwsem);
1616 return 0;
1617}
1618
Takashi Iwai12cddbd2014-10-30 13:44:34 +01001619/**
1620 * snd_ctl_register_ioctl - register the device-specific control-ioctls
1621 * @fcn: ioctl callback function
1622 *
1623 * called from each device manager like pcm.c, hwdep.c, etc.
1624 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001625int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1626{
1627 return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1628}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +02001629EXPORT_SYMBOL(snd_ctl_register_ioctl);
1630
Linus Torvalds1da177e2005-04-16 15:20:36 -07001631#ifdef CONFIG_COMPAT
Takashi Iwai12cddbd2014-10-30 13:44:34 +01001632/**
1633 * snd_ctl_register_ioctl_compat - register the device-specific 32bit compat
1634 * control-ioctls
1635 * @fcn: ioctl callback function
1636 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001637int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1638{
1639 return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1640}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +02001641EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001642#endif
1643
1644/*
1645 * de-register the device-specific control-ioctls.
1646 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001647static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1648 struct list_head *lists)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001649{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001650 struct snd_kctl_ioctl *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001652 if (snd_BUG_ON(!fcn))
1653 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001654 down_write(&snd_ioctl_rwsem);
Johannes Berg9244b2c2006-10-05 16:02:22 +02001655 list_for_each_entry(p, lists, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001656 if (p->fioctl == fcn) {
1657 list_del(&p->list);
1658 up_write(&snd_ioctl_rwsem);
1659 kfree(p);
1660 return 0;
1661 }
1662 }
1663 up_write(&snd_ioctl_rwsem);
1664 snd_BUG();
1665 return -EINVAL;
1666}
1667
Takashi Iwai12cddbd2014-10-30 13:44:34 +01001668/**
1669 * snd_ctl_unregister_ioctl - de-register the device-specific control-ioctls
1670 * @fcn: ioctl callback function to unregister
1671 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001672int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1673{
1674 return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1675}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +02001676EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1677
Linus Torvalds1da177e2005-04-16 15:20:36 -07001678#ifdef CONFIG_COMPAT
Takashi Iwai12cddbd2014-10-30 13:44:34 +01001679/**
1680 * snd_ctl_unregister_ioctl - de-register the device-specific compat 32bit
1681 * control-ioctls
1682 * @fcn: ioctl callback function to unregister
1683 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001684int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1685{
1686 return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1687}
Takashi Iwaic0d3fb32006-04-28 15:13:39 +02001688EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001689#endif
1690
1691static int snd_ctl_fasync(int fd, struct file * file, int on)
1692{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001693 struct snd_ctl_file *ctl;
Jonathan Corbet60aa4922009-02-01 14:52:56 -07001694
Linus Torvalds1da177e2005-04-16 15:20:36 -07001695 ctl = file->private_data;
Jonathan Corbet60aa4922009-02-01 14:52:56 -07001696 return fasync_helper(fd, file, on, &ctl->fasync);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001697}
1698
Takashi Iwai23c18d42014-02-19 14:30:29 +01001699/* return the preferred subdevice number if already assigned;
1700 * otherwise return -1
1701 */
1702int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type)
1703{
1704 struct snd_ctl_file *kctl;
1705 int subdevice = -1;
1706
1707 read_lock(&card->ctl_files_rwlock);
1708 list_for_each_entry(kctl, &card->ctl_files, list) {
1709 if (kctl->pid == task_pid(current)) {
1710 subdevice = kctl->preferred_subdevice[type];
1711 if (subdevice != -1)
1712 break;
1713 }
1714 }
1715 read_unlock(&card->ctl_files_rwlock);
1716 return subdevice;
1717}
1718EXPORT_SYMBOL_GPL(snd_ctl_get_preferred_subdevice);
1719
Linus Torvalds1da177e2005-04-16 15:20:36 -07001720/*
1721 * ioctl32 compat
1722 */
1723#ifdef CONFIG_COMPAT
1724#include "control_compat.c"
1725#else
1726#define snd_ctl_ioctl_compat NULL
1727#endif
1728
1729/*
1730 * INIT PART
1731 */
1732
Arjan van de Ven9c2e08c2007-02-12 00:55:37 -08001733static const struct file_operations snd_ctl_f_ops =
Linus Torvalds1da177e2005-04-16 15:20:36 -07001734{
1735 .owner = THIS_MODULE,
1736 .read = snd_ctl_read,
1737 .open = snd_ctl_open,
1738 .release = snd_ctl_release,
Takashi Iwai02f48652010-04-13 11:49:04 +02001739 .llseek = no_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001740 .poll = snd_ctl_poll,
1741 .unlocked_ioctl = snd_ctl_ioctl,
1742 .compat_ioctl = snd_ctl_ioctl_compat,
1743 .fasync = snd_ctl_fasync,
1744};
1745
Linus Torvalds1da177e2005-04-16 15:20:36 -07001746/*
1747 * registration of the control device
1748 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001749static int snd_ctl_dev_register(struct snd_device *device)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001750{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001751 struct snd_card *card = device->device_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001752
Takashi Iwai40a4b262015-01-30 08:34:58 +01001753 return snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1754 &snd_ctl_f_ops, card, &card->ctl_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001755}
1756
1757/*
1758 * disconnection of the control device
1759 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001760static int snd_ctl_dev_disconnect(struct snd_device *device)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001761{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001762 struct snd_card *card = device->device_data;
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001763 struct snd_ctl_file *ctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001764
Takashi Iwaid8009882008-09-07 12:51:13 +02001765 read_lock(&card->ctl_files_rwlock);
Johannes Berg9244b2c2006-10-05 16:02:22 +02001766 list_for_each_entry(ctl, &card->ctl_files, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001767 wake_up(&ctl->change_sleep);
1768 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1769 }
Takashi Iwaid8009882008-09-07 12:51:13 +02001770 read_unlock(&card->ctl_files_rwlock);
Takashi Iwaic4614822006-06-23 14:38:23 +02001771
Takashi Iwai40a4b262015-01-30 08:34:58 +01001772 return snd_unregister_device(&card->ctl_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001773}
1774
1775/*
1776 * free all controls
1777 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001778static int snd_ctl_dev_free(struct snd_device *device)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001779{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001780 struct snd_card *card = device->device_data;
1781 struct snd_kcontrol *control;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001782
1783 down_write(&card->controls_rwsem);
1784 while (!list_empty(&card->controls)) {
1785 control = snd_kcontrol(card->controls.next);
1786 snd_ctl_remove(card, control);
1787 }
1788 up_write(&card->controls_rwsem);
Takashi Iwai0fcd9f42015-01-29 16:41:27 +01001789 put_device(&card->ctl_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001790 return 0;
1791}
1792
1793/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001794 * create control core:
1795 * called from init.c
1796 */
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001797int snd_ctl_create(struct snd_card *card)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001798{
Takashi Iwai82e9bae2005-11-17 13:53:23 +01001799 static struct snd_device_ops ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001800 .dev_free = snd_ctl_dev_free,
1801 .dev_register = snd_ctl_dev_register,
1802 .dev_disconnect = snd_ctl_dev_disconnect,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001803 };
Takashi Iwai0fcd9f42015-01-29 16:41:27 +01001804 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001805
Takashi Iwai7eaa9432008-08-08 17:09:09 +02001806 if (snd_BUG_ON(!card))
1807 return -ENXIO;
Takashi Iwai0fcd9f42015-01-29 16:41:27 +01001808 if (snd_BUG_ON(card->number < 0 || card->number >= SNDRV_CARDS))
1809 return -ENXIO;
1810
1811 snd_device_initialize(&card->ctl_dev, card);
1812 dev_set_name(&card->ctl_dev, "controlC%d", card->number);
1813
1814 err = snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1815 if (err < 0)
1816 put_device(&card->ctl_dev);
1817 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001818}
Takashi Iwaib9ed4f22007-07-23 15:41:34 +02001819
1820/*
Clemens Ladisch96007322011-01-10 16:25:44 +01001821 * Frequently used control callbacks/helpers
Takashi Iwaib9ed4f22007-07-23 15:41:34 +02001822 */
Takashi Iwai12cddbd2014-10-30 13:44:34 +01001823
1824/**
1825 * snd_ctl_boolean_mono_info - Helper function for a standard boolean info
1826 * callback with a mono channel
1827 * @kcontrol: the kcontrol instance
1828 * @uinfo: info to store
1829 *
1830 * This is a function that can be used as info callback for a standard
1831 * boolean control with a single mono channel.
1832 */
Takashi Iwaib9ed4f22007-07-23 15:41:34 +02001833int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1834 struct snd_ctl_elem_info *uinfo)
1835{
1836 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1837 uinfo->count = 1;
1838 uinfo->value.integer.min = 0;
1839 uinfo->value.integer.max = 1;
1840 return 0;
1841}
Takashi Iwaib9ed4f22007-07-23 15:41:34 +02001842EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1843
Takashi Iwai12cddbd2014-10-30 13:44:34 +01001844/**
1845 * snd_ctl_boolean_stereo_info - Helper function for a standard boolean info
1846 * callback with stereo two channels
1847 * @kcontrol: the kcontrol instance
1848 * @uinfo: info to store
1849 *
1850 * This is a function that can be used as info callback for a standard
1851 * boolean control with stereo two channels.
1852 */
Takashi Iwaib9ed4f22007-07-23 15:41:34 +02001853int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1854 struct snd_ctl_elem_info *uinfo)
1855{
1856 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1857 uinfo->count = 2;
1858 uinfo->value.integer.min = 0;
1859 uinfo->value.integer.max = 1;
1860 return 0;
1861}
Takashi Iwaib9ed4f22007-07-23 15:41:34 +02001862EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);
Clemens Ladisch96007322011-01-10 16:25:44 +01001863
1864/**
1865 * snd_ctl_enum_info - fills the info structure for an enumerated control
1866 * @info: the structure to be filled
1867 * @channels: the number of the control's channels; often one
1868 * @items: the number of control values; also the size of @names
1869 * @names: an array containing the names of all control values
1870 *
1871 * Sets all required fields in @info to their appropriate values.
1872 * If the control's accessibility is not the default (readable and writable),
1873 * the caller has to fill @info->access.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +01001874 *
1875 * Return: Zero.
Clemens Ladisch96007322011-01-10 16:25:44 +01001876 */
1877int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
1878 unsigned int items, const char *const names[])
1879{
1880 info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
1881 info->count = channels;
1882 info->value.enumerated.items = items;
Takashi Iwaia7e6fb92014-10-20 18:08:50 +02001883 if (!items)
1884 return 0;
Clemens Ladisch96007322011-01-10 16:25:44 +01001885 if (info->value.enumerated.item >= items)
1886 info->value.enumerated.item = items - 1;
Takashi Iwaidf803e12014-10-20 18:07:21 +02001887 WARN(strlen(names[info->value.enumerated.item]) >= sizeof(info->value.enumerated.name),
1888 "ALSA: too long item name '%s'\n",
1889 names[info->value.enumerated.item]);
Clemens Ladisch96007322011-01-10 16:25:44 +01001890 strlcpy(info->value.enumerated.name,
1891 names[info->value.enumerated.item],
1892 sizeof(info->value.enumerated.name));
1893 return 0;
1894}
1895EXPORT_SYMBOL(snd_ctl_enum_info);