Commit | Line | Data |
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1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * Routines for driver control interface | |
c1017a4c | 4 | * Copyright (c) by Jaroslav Kysela <perex@perex.cz> |
1da177e4 LT |
5 | */ |
6 | ||
1da177e4 LT |
7 | #include <linux/threads.h> |
8 | #include <linux/interrupt.h> | |
da155d5b | 9 | #include <linux/module.h> |
1da177e4 LT |
10 | #include <linux/slab.h> |
11 | #include <linux/vmalloc.h> | |
12 | #include <linux/time.h> | |
88a89037 | 13 | #include <linux/mm.h> |
174cd4b1 | 14 | #include <linux/sched/signal.h> |
1da177e4 LT |
15 | #include <sound/core.h> |
16 | #include <sound/minors.h> | |
17 | #include <sound/info.h> | |
18 | #include <sound/control.h> | |
19 | ||
20 | /* max number of user-defined controls */ | |
21 | #define MAX_USER_CONTROLS 32 | |
5591bf07 | 22 | #define MAX_CONTROL_COUNT 1028 |
1da177e4 | 23 | |
82e9bae6 | 24 | struct snd_kctl_ioctl { |
1da177e4 LT |
25 | struct list_head list; /* list of all ioctls */ |
26 | snd_kctl_ioctl_func_t fioctl; | |
82e9bae6 | 27 | }; |
1da177e4 LT |
28 | |
29 | static DECLARE_RWSEM(snd_ioctl_rwsem); | |
30 | static LIST_HEAD(snd_control_ioctls); | |
31 | #ifdef CONFIG_COMPAT | |
32 | static LIST_HEAD(snd_control_compat_ioctls); | |
33 | #endif | |
34 | ||
35 | static int snd_ctl_open(struct inode *inode, struct file *file) | |
36 | { | |
1da177e4 | 37 | unsigned long flags; |
82e9bae6 TI |
38 | struct snd_card *card; |
39 | struct snd_ctl_file *ctl; | |
23c18d4b | 40 | int i, err; |
1da177e4 | 41 | |
c5bf68fe | 42 | err = stream_open(inode, file); |
02f4865f TI |
43 | if (err < 0) |
44 | return err; | |
45 | ||
f87135f5 | 46 | card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL); |
1da177e4 LT |
47 | if (!card) { |
48 | err = -ENODEV; | |
49 | goto __error1; | |
50 | } | |
51 | err = snd_card_file_add(card, file); | |
52 | if (err < 0) { | |
53 | err = -ENODEV; | |
54 | goto __error1; | |
55 | } | |
56 | if (!try_module_get(card->module)) { | |
57 | err = -EFAULT; | |
58 | goto __error2; | |
59 | } | |
ca2c0966 | 60 | ctl = kzalloc(sizeof(*ctl), GFP_KERNEL); |
1da177e4 LT |
61 | if (ctl == NULL) { |
62 | err = -ENOMEM; | |
63 | goto __error; | |
64 | } | |
65 | INIT_LIST_HEAD(&ctl->events); | |
66 | init_waitqueue_head(&ctl->change_sleep); | |
67 | spin_lock_init(&ctl->read_lock); | |
68 | ctl->card = card; | |
23c18d4b TI |
69 | for (i = 0; i < SND_CTL_SUBDEV_ITEMS; i++) |
70 | ctl->preferred_subdevice[i] = -1; | |
25d27ede | 71 | ctl->pid = get_pid(task_pid(current)); |
1da177e4 LT |
72 | file->private_data = ctl; |
73 | write_lock_irqsave(&card->ctl_files_rwlock, flags); | |
74 | list_add_tail(&ctl->list, &card->ctl_files); | |
75 | write_unlock_irqrestore(&card->ctl_files_rwlock, flags); | |
a0830dbd | 76 | snd_card_unref(card); |
1da177e4 LT |
77 | return 0; |
78 | ||
79 | __error: | |
80 | module_put(card->module); | |
81 | __error2: | |
82 | snd_card_file_remove(card, file); | |
83 | __error1: | |
a0830dbd TI |
84 | if (card) |
85 | snd_card_unref(card); | |
1da177e4 LT |
86 | return err; |
87 | } | |
88 | ||
82e9bae6 | 89 | static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl) |
1da177e4 | 90 | { |
7507e8da | 91 | unsigned long flags; |
82e9bae6 | 92 | struct snd_kctl_event *cread; |
dd5f313b | 93 | |
7507e8da | 94 | spin_lock_irqsave(&ctl->read_lock, flags); |
1da177e4 LT |
95 | while (!list_empty(&ctl->events)) { |
96 | cread = snd_kctl_event(ctl->events.next); | |
97 | list_del(&cread->list); | |
98 | kfree(cread); | |
99 | } | |
7507e8da | 100 | spin_unlock_irqrestore(&ctl->read_lock, flags); |
1da177e4 LT |
101 | } |
102 | ||
103 | static int snd_ctl_release(struct inode *inode, struct file *file) | |
104 | { | |
105 | unsigned long flags; | |
82e9bae6 TI |
106 | struct snd_card *card; |
107 | struct snd_ctl_file *ctl; | |
108 | struct snd_kcontrol *control; | |
1da177e4 LT |
109 | unsigned int idx; |
110 | ||
111 | ctl = file->private_data; | |
1da177e4 LT |
112 | file->private_data = NULL; |
113 | card = ctl->card; | |
114 | write_lock_irqsave(&card->ctl_files_rwlock, flags); | |
115 | list_del(&ctl->list); | |
116 | write_unlock_irqrestore(&card->ctl_files_rwlock, flags); | |
117 | down_write(&card->controls_rwsem); | |
9244b2c3 | 118 | list_for_each_entry(control, &card->controls, list) |
1da177e4 LT |
119 | for (idx = 0; idx < control->count; idx++) |
120 | if (control->vd[idx].owner == ctl) | |
121 | control->vd[idx].owner = NULL; | |
1da177e4 LT |
122 | up_write(&card->controls_rwsem); |
123 | snd_ctl_empty_read_queue(ctl); | |
25d27ede | 124 | put_pid(ctl->pid); |
1da177e4 LT |
125 | kfree(ctl); |
126 | module_put(card->module); | |
127 | snd_card_file_remove(card, file); | |
128 | return 0; | |
129 | } | |
130 | ||
12cddbd8 TI |
131 | /** |
132 | * snd_ctl_notify - Send notification to user-space for a control change | |
133 | * @card: the card to send notification | |
134 | * @mask: the event mask, SNDRV_CTL_EVENT_* | |
135 | * @id: the ctl element id to send notification | |
136 | * | |
137 | * This function adds an event record with the given id and mask, appends | |
138 | * to the list and wakes up the user-space for notification. This can be | |
139 | * called in the atomic context. | |
140 | */ | |
82e9bae6 TI |
141 | void snd_ctl_notify(struct snd_card *card, unsigned int mask, |
142 | struct snd_ctl_elem_id *id) | |
1da177e4 LT |
143 | { |
144 | unsigned long flags; | |
82e9bae6 TI |
145 | struct snd_ctl_file *ctl; |
146 | struct snd_kctl_event *ev; | |
dd5f313b | 147 | |
7eaa943c TI |
148 | if (snd_BUG_ON(!card || !id)) |
149 | return; | |
f388cdcd TI |
150 | if (card->shutdown) |
151 | return; | |
1da177e4 | 152 | read_lock(&card->ctl_files_rwlock); |
8eeaa2f9 | 153 | #if IS_ENABLED(CONFIG_SND_MIXER_OSS) |
1da177e4 LT |
154 | card->mixer_oss_change_count++; |
155 | #endif | |
9244b2c3 | 156 | list_for_each_entry(ctl, &card->ctl_files, list) { |
1da177e4 LT |
157 | if (!ctl->subscribed) |
158 | continue; | |
159 | spin_lock_irqsave(&ctl->read_lock, flags); | |
9244b2c3 | 160 | list_for_each_entry(ev, &ctl->events, list) { |
1da177e4 LT |
161 | if (ev->id.numid == id->numid) { |
162 | ev->mask |= mask; | |
163 | goto _found; | |
164 | } | |
165 | } | |
ca2c0966 | 166 | ev = kzalloc(sizeof(*ev), GFP_ATOMIC); |
1da177e4 LT |
167 | if (ev) { |
168 | ev->id = *id; | |
169 | ev->mask = mask; | |
170 | list_add_tail(&ev->list, &ctl->events); | |
171 | } else { | |
bb009457 | 172 | dev_err(card->dev, "No memory available to allocate event\n"); |
1da177e4 LT |
173 | } |
174 | _found: | |
175 | wake_up(&ctl->change_sleep); | |
176 | spin_unlock_irqrestore(&ctl->read_lock, flags); | |
177 | kill_fasync(&ctl->fasync, SIGIO, POLL_IN); | |
178 | } | |
179 | read_unlock(&card->ctl_files_rwlock); | |
180 | } | |
c0d3fb39 TI |
181 | EXPORT_SYMBOL(snd_ctl_notify); |
182 | ||
1da177e4 | 183 | /** |
2225e79b TS |
184 | * snd_ctl_new - create a new control instance with some elements |
185 | * @kctl: the pointer to store new control instance | |
186 | * @count: the number of elements in this control | |
187 | * @access: the default access flags for elements in this control | |
188 | * @file: given when locking these elements | |
1da177e4 | 189 | * |
2225e79b TS |
190 | * Allocates a memory object for a new control instance. The instance has |
191 | * elements as many as the given number (@count). Each element has given | |
192 | * access permissions (@access). Each element is locked when @file is given. | |
1da177e4 | 193 | * |
2225e79b | 194 | * Return: 0 on success, error code on failure |
1da177e4 | 195 | */ |
2225e79b TS |
196 | static int snd_ctl_new(struct snd_kcontrol **kctl, unsigned int count, |
197 | unsigned int access, struct snd_ctl_file *file) | |
1da177e4 | 198 | { |
1da177e4 | 199 | unsigned int idx; |
dd5f313b | 200 | |
2225e79b TS |
201 | if (count == 0 || count > MAX_CONTROL_COUNT) |
202 | return -EINVAL; | |
5591bf07 | 203 | |
65be9580 | 204 | *kctl = kzalloc(struct_size(*kctl, vd, count), GFP_KERNEL); |
ec0e9937 | 205 | if (!*kctl) |
2225e79b | 206 | return -ENOMEM; |
2225e79b TS |
207 | |
208 | for (idx = 0; idx < count; idx++) { | |
209 | (*kctl)->vd[idx].access = access; | |
210 | (*kctl)->vd[idx].owner = file; | |
211 | } | |
212 | (*kctl)->count = count; | |
213 | ||
214 | return 0; | |
1da177e4 LT |
215 | } |
216 | ||
217 | /** | |
218 | * snd_ctl_new1 - create a control instance from the template | |
219 | * @ncontrol: the initialization record | |
220 | * @private_data: the private data to set | |
221 | * | |
dd5f313b | 222 | * Allocates a new struct snd_kcontrol instance and initialize from the given |
1da177e4 LT |
223 | * template. When the access field of ncontrol is 0, it's assumed as |
224 | * READWRITE access. When the count field is 0, it's assumes as one. | |
225 | * | |
eb7c06e8 | 226 | * Return: The pointer of the newly generated instance, or %NULL on failure. |
1da177e4 | 227 | */ |
82e9bae6 TI |
228 | struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol, |
229 | void *private_data) | |
1da177e4 | 230 | { |
2225e79b TS |
231 | struct snd_kcontrol *kctl; |
232 | unsigned int count; | |
1da177e4 | 233 | unsigned int access; |
2225e79b | 234 | int err; |
dd5f313b | 235 | |
7eaa943c TI |
236 | if (snd_BUG_ON(!ncontrol || !ncontrol->info)) |
237 | return NULL; | |
2225e79b TS |
238 | |
239 | count = ncontrol->count; | |
240 | if (count == 0) | |
241 | count = 1; | |
242 | ||
243 | access = ncontrol->access; | |
244 | if (access == 0) | |
245 | access = SNDRV_CTL_ELEM_ACCESS_READWRITE; | |
246 | access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE | | |
247 | SNDRV_CTL_ELEM_ACCESS_VOLATILE | | |
248 | SNDRV_CTL_ELEM_ACCESS_INACTIVE | | |
249 | SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE | | |
250 | SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND | | |
251 | SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK); | |
252 | ||
253 | err = snd_ctl_new(&kctl, count, access, NULL); | |
254 | if (err < 0) | |
255 | return NULL; | |
256 | ||
257 | /* The 'numid' member is decided when calling snd_ctl_add(). */ | |
258 | kctl->id.iface = ncontrol->iface; | |
259 | kctl->id.device = ncontrol->device; | |
260 | kctl->id.subdevice = ncontrol->subdevice; | |
366840d7 | 261 | if (ncontrol->name) { |
2225e79b TS |
262 | strlcpy(kctl->id.name, ncontrol->name, sizeof(kctl->id.name)); |
263 | if (strcmp(ncontrol->name, kctl->id.name) != 0) | |
bb009457 | 264 | pr_warn("ALSA: Control name '%s' truncated to '%s'\n", |
2225e79b | 265 | ncontrol->name, kctl->id.name); |
366840d7 | 266 | } |
2225e79b TS |
267 | kctl->id.index = ncontrol->index; |
268 | ||
269 | kctl->info = ncontrol->info; | |
270 | kctl->get = ncontrol->get; | |
271 | kctl->put = ncontrol->put; | |
272 | kctl->tlv.p = ncontrol->tlv.p; | |
273 | ||
274 | kctl->private_value = ncontrol->private_value; | |
275 | kctl->private_data = private_data; | |
276 | ||
277 | return kctl; | |
1da177e4 | 278 | } |
c0d3fb39 TI |
279 | EXPORT_SYMBOL(snd_ctl_new1); |
280 | ||
1da177e4 LT |
281 | /** |
282 | * snd_ctl_free_one - release the control instance | |
283 | * @kcontrol: the control instance | |
284 | * | |
285 | * Releases the control instance created via snd_ctl_new() | |
286 | * or snd_ctl_new1(). | |
287 | * Don't call this after the control was added to the card. | |
288 | */ | |
82e9bae6 | 289 | void snd_ctl_free_one(struct snd_kcontrol *kcontrol) |
1da177e4 LT |
290 | { |
291 | if (kcontrol) { | |
292 | if (kcontrol->private_free) | |
293 | kcontrol->private_free(kcontrol); | |
294 | kfree(kcontrol); | |
295 | } | |
296 | } | |
c0d3fb39 TI |
297 | EXPORT_SYMBOL(snd_ctl_free_one); |
298 | ||
0e82e5fa CL |
299 | static bool snd_ctl_remove_numid_conflict(struct snd_card *card, |
300 | unsigned int count) | |
1da177e4 | 301 | { |
82e9bae6 | 302 | struct snd_kcontrol *kctl; |
1da177e4 | 303 | |
ac902c11 LPC |
304 | /* Make sure that the ids assigned to the control do not wrap around */ |
305 | if (card->last_numid >= UINT_MAX - count) | |
306 | card->last_numid = 0; | |
307 | ||
9244b2c3 | 308 | list_for_each_entry(kctl, &card->controls, list) { |
7c733587 | 309 | if (kctl->id.numid < card->last_numid + 1 + count && |
0e82e5fa CL |
310 | kctl->id.numid + kctl->count > card->last_numid + 1) { |
311 | card->last_numid = kctl->id.numid + kctl->count - 1; | |
312 | return true; | |
313 | } | |
1da177e4 | 314 | } |
0e82e5fa | 315 | return false; |
1da177e4 LT |
316 | } |
317 | ||
82e9bae6 | 318 | static int snd_ctl_find_hole(struct snd_card *card, unsigned int count) |
1da177e4 | 319 | { |
0e82e5fa | 320 | unsigned int iter = 100000; |
1da177e4 | 321 | |
0e82e5fa | 322 | while (snd_ctl_remove_numid_conflict(card, count)) { |
1da177e4 LT |
323 | if (--iter == 0) { |
324 | /* this situation is very unlikely */ | |
bb009457 | 325 | dev_err(card->dev, "unable to allocate new control numid\n"); |
1da177e4 LT |
326 | return -ENOMEM; |
327 | } | |
1da177e4 LT |
328 | } |
329 | return 0; | |
330 | } | |
331 | ||
3103c08f TI |
332 | enum snd_ctl_add_mode { |
333 | CTL_ADD_EXCLUSIVE, CTL_REPLACE, CTL_ADD_ON_REPLACE, | |
334 | }; | |
335 | ||
336 | /* add/replace a new kcontrol object; call with card->controls_rwsem locked */ | |
337 | static int __snd_ctl_add_replace(struct snd_card *card, | |
338 | struct snd_kcontrol *kcontrol, | |
339 | enum snd_ctl_add_mode mode) | |
e1a7bfe3 TI |
340 | { |
341 | struct snd_ctl_elem_id id; | |
342 | unsigned int idx; | |
343 | unsigned int count; | |
3103c08f TI |
344 | struct snd_kcontrol *old; |
345 | int err; | |
e1a7bfe3 TI |
346 | |
347 | id = kcontrol->id; | |
348 | if (id.index > UINT_MAX - kcontrol->count) | |
349 | return -EINVAL; | |
350 | ||
3103c08f TI |
351 | old = snd_ctl_find_id(card, &id); |
352 | if (!old) { | |
353 | if (mode == CTL_REPLACE) | |
354 | return -EINVAL; | |
355 | } else { | |
356 | if (mode == CTL_ADD_EXCLUSIVE) { | |
357 | dev_err(card->dev, | |
358 | "control %i:%i:%i:%s:%i is already present\n", | |
359 | id.iface, id.device, id.subdevice, id.name, | |
360 | id.index); | |
361 | return -EBUSY; | |
362 | } | |
363 | ||
364 | err = snd_ctl_remove(card, old); | |
365 | if (err < 0) | |
366 | return err; | |
e1a7bfe3 TI |
367 | } |
368 | ||
369 | if (snd_ctl_find_hole(card, kcontrol->count) < 0) | |
370 | return -ENOMEM; | |
371 | ||
372 | list_add_tail(&kcontrol->list, &card->controls); | |
373 | card->controls_count += kcontrol->count; | |
374 | kcontrol->id.numid = card->last_numid + 1; | |
375 | card->last_numid += kcontrol->count; | |
376 | ||
377 | id = kcontrol->id; | |
378 | count = kcontrol->count; | |
379 | for (idx = 0; idx < count; idx++, id.index++, id.numid++) | |
380 | snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id); | |
381 | ||
382 | return 0; | |
383 | } | |
384 | ||
3103c08f TI |
385 | static int snd_ctl_add_replace(struct snd_card *card, |
386 | struct snd_kcontrol *kcontrol, | |
387 | enum snd_ctl_add_mode mode) | |
1da177e4 | 388 | { |
c6077b30 | 389 | int err = -EINVAL; |
1da177e4 | 390 | |
73e77ba0 | 391 | if (! kcontrol) |
c6077b30 | 392 | return err; |
7eaa943c TI |
393 | if (snd_BUG_ON(!card || !kcontrol->info)) |
394 | goto error; | |
883a1d49 | 395 | |
1da177e4 | 396 | down_write(&card->controls_rwsem); |
3103c08f | 397 | err = __snd_ctl_add_replace(card, kcontrol, mode); |
1da177e4 | 398 | up_write(&card->controls_rwsem); |
e1a7bfe3 TI |
399 | if (err < 0) |
400 | goto error; | |
1da177e4 | 401 | return 0; |
c6077b30 TI |
402 | |
403 | error: | |
404 | snd_ctl_free_one(kcontrol); | |
405 | return err; | |
1da177e4 | 406 | } |
3103c08f TI |
407 | |
408 | /** | |
409 | * snd_ctl_add - add the control instance to the card | |
410 | * @card: the card instance | |
411 | * @kcontrol: the control instance to add | |
412 | * | |
413 | * Adds the control instance created via snd_ctl_new() or | |
414 | * snd_ctl_new1() to the given card. Assigns also an unique | |
415 | * numid used for fast search. | |
416 | * | |
417 | * It frees automatically the control which cannot be added. | |
418 | * | |
419 | * Return: Zero if successful, or a negative error code on failure. | |
420 | * | |
421 | */ | |
422 | int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol) | |
423 | { | |
424 | return snd_ctl_add_replace(card, kcontrol, CTL_ADD_EXCLUSIVE); | |
425 | } | |
c0d3fb39 TI |
426 | EXPORT_SYMBOL(snd_ctl_add); |
427 | ||
66b5b972 DP |
428 | /** |
429 | * snd_ctl_replace - replace the control instance of the card | |
430 | * @card: the card instance | |
431 | * @kcontrol: the control instance to replace | |
432 | * @add_on_replace: add the control if not already added | |
433 | * | |
434 | * Replaces the given control. If the given control does not exist | |
435 | * and the add_on_replace flag is set, the control is added. If the | |
436 | * control exists, it is destroyed first. | |
437 | * | |
66b5b972 | 438 | * It frees automatically the control which cannot be added or replaced. |
eb7c06e8 YB |
439 | * |
440 | * Return: Zero if successful, or a negative error code on failure. | |
66b5b972 DP |
441 | */ |
442 | int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, | |
443 | bool add_on_replace) | |
444 | { | |
3103c08f TI |
445 | return snd_ctl_add_replace(card, kcontrol, |
446 | add_on_replace ? CTL_ADD_ON_REPLACE : CTL_REPLACE); | |
66b5b972 DP |
447 | } |
448 | EXPORT_SYMBOL(snd_ctl_replace); | |
449 | ||
1da177e4 LT |
450 | /** |
451 | * snd_ctl_remove - remove the control from the card and release it | |
452 | * @card: the card instance | |
453 | * @kcontrol: the control instance to remove | |
454 | * | |
455 | * Removes the control from the card and then releases the instance. | |
456 | * You don't need to call snd_ctl_free_one(). You must be in | |
457 | * the write lock - down_write(&card->controls_rwsem). | |
eb7c06e8 YB |
458 | * |
459 | * Return: 0 if successful, or a negative error code on failure. | |
1da177e4 | 460 | */ |
82e9bae6 | 461 | int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol) |
1da177e4 | 462 | { |
82e9bae6 | 463 | struct snd_ctl_elem_id id; |
1da177e4 LT |
464 | unsigned int idx; |
465 | ||
7eaa943c TI |
466 | if (snd_BUG_ON(!card || !kcontrol)) |
467 | return -EINVAL; | |
1da177e4 LT |
468 | list_del(&kcontrol->list); |
469 | card->controls_count -= kcontrol->count; | |
470 | id = kcontrol->id; | |
471 | for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++) | |
472 | snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id); | |
473 | snd_ctl_free_one(kcontrol); | |
474 | return 0; | |
475 | } | |
c0d3fb39 TI |
476 | EXPORT_SYMBOL(snd_ctl_remove); |
477 | ||
1da177e4 LT |
478 | /** |
479 | * snd_ctl_remove_id - remove the control of the given id and release it | |
480 | * @card: the card instance | |
481 | * @id: the control id to remove | |
482 | * | |
483 | * Finds the control instance with the given id, removes it from the | |
484 | * card list and releases it. | |
eb7c06e8 YB |
485 | * |
486 | * Return: 0 if successful, or a negative error code on failure. | |
1da177e4 | 487 | */ |
82e9bae6 | 488 | int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id) |
1da177e4 | 489 | { |
82e9bae6 | 490 | struct snd_kcontrol *kctl; |
1da177e4 LT |
491 | int ret; |
492 | ||
493 | down_write(&card->controls_rwsem); | |
494 | kctl = snd_ctl_find_id(card, id); | |
495 | if (kctl == NULL) { | |
496 | up_write(&card->controls_rwsem); | |
497 | return -ENOENT; | |
498 | } | |
499 | ret = snd_ctl_remove(card, kctl); | |
500 | up_write(&card->controls_rwsem); | |
501 | return ret; | |
502 | } | |
c0d3fb39 TI |
503 | EXPORT_SYMBOL(snd_ctl_remove_id); |
504 | ||
1da177e4 | 505 | /** |
f217ac59 | 506 | * snd_ctl_remove_user_ctl - remove and release the unlocked user control |
1da177e4 LT |
507 | * @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. | |
eb7c06e8 YB |
512 | * |
513 | * Return: 0 if successful, or a negative error code on failure. | |
1da177e4 | 514 | */ |
f217ac59 CL |
515 | static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file, |
516 | struct snd_ctl_elem_id *id) | |
1da177e4 | 517 | { |
82e9bae6 TI |
518 | struct snd_card *card = file->card; |
519 | struct snd_kcontrol *kctl; | |
1da177e4 LT |
520 | int idx, ret; |
521 | ||
522 | down_write(&card->controls_rwsem); | |
523 | kctl = snd_ctl_find_id(card, id); | |
524 | if (kctl == NULL) { | |
317b8081 CL |
525 | ret = -ENOENT; |
526 | goto error; | |
1da177e4 | 527 | } |
18dd0aa5 CL |
528 | if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) { |
529 | ret = -EINVAL; | |
530 | goto error; | |
531 | } | |
1da177e4 LT |
532 | for (idx = 0; idx < kctl->count; idx++) |
533 | if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) { | |
317b8081 CL |
534 | ret = -EBUSY; |
535 | goto error; | |
1da177e4 LT |
536 | } |
537 | ret = snd_ctl_remove(card, kctl); | |
f217ac59 CL |
538 | if (ret < 0) |
539 | goto error; | |
540 | card->user_ctl_count--; | |
317b8081 | 541 | error: |
1da177e4 LT |
542 | up_write(&card->controls_rwsem); |
543 | return ret; | |
544 | } | |
545 | ||
3cbdd753 TI |
546 | /** |
547 | * 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. | |
c78497e0 | 554 | * The given ID data is filled with full information. |
3cbdd753 | 555 | * |
eb7c06e8 | 556 | * Return: 0 if unchanged, 1 if changed, or a negative error code on failure. |
3cbdd753 TI |
557 | */ |
558 | int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id, | |
559 | int active) | |
560 | { | |
561 | struct snd_kcontrol *kctl; | |
562 | struct snd_kcontrol_volatile *vd; | |
563 | unsigned int index_offset; | |
564 | int ret; | |
565 | ||
566 | down_write(&card->controls_rwsem); | |
567 | kctl = snd_ctl_find_id(card, id); | |
568 | if (kctl == NULL) { | |
569 | ret = -ENOENT; | |
570 | goto unlock; | |
571 | } | |
31584ed1 | 572 | index_offset = snd_ctl_get_ioff(kctl, id); |
3cbdd753 TI |
573 | vd = &kctl->vd[index_offset]; |
574 | ret = 0; | |
575 | if (active) { | |
576 | if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE)) | |
577 | goto unlock; | |
578 | vd->access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE; | |
579 | } else { | |
580 | if (vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE) | |
581 | goto unlock; | |
582 | vd->access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE; | |
583 | } | |
c78497e0 | 584 | snd_ctl_build_ioff(id, kctl, index_offset); |
3cbdd753 TI |
585 | ret = 1; |
586 | unlock: | |
587 | up_write(&card->controls_rwsem); | |
588 | if (ret > 0) | |
589 | snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, id); | |
590 | return ret; | |
591 | } | |
592 | EXPORT_SYMBOL_GPL(snd_ctl_activate_id); | |
593 | ||
1da177e4 LT |
594 | /** |
595 | * snd_ctl_rename_id - replace the id of a control on the card | |
596 | * @card: the card instance | |
597 | * @src_id: the old id | |
598 | * @dst_id: the new id | |
599 | * | |
600 | * Finds the control with the old id from the card, and replaces the | |
601 | * id with the new one. | |
602 | * | |
eb7c06e8 | 603 | * Return: Zero if successful, or a negative error code on failure. |
1da177e4 | 604 | */ |
82e9bae6 TI |
605 | int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id, |
606 | struct snd_ctl_elem_id *dst_id) | |
1da177e4 | 607 | { |
82e9bae6 | 608 | struct snd_kcontrol *kctl; |
1da177e4 LT |
609 | |
610 | down_write(&card->controls_rwsem); | |
611 | kctl = snd_ctl_find_id(card, src_id); | |
612 | if (kctl == NULL) { | |
613 | up_write(&card->controls_rwsem); | |
614 | return -ENOENT; | |
615 | } | |
616 | kctl->id = *dst_id; | |
617 | kctl->id.numid = card->last_numid + 1; | |
618 | card->last_numid += kctl->count; | |
619 | up_write(&card->controls_rwsem); | |
620 | return 0; | |
621 | } | |
c0d3fb39 TI |
622 | EXPORT_SYMBOL(snd_ctl_rename_id); |
623 | ||
1da177e4 LT |
624 | /** |
625 | * snd_ctl_find_numid - find the control instance with the given number-id | |
626 | * @card: the card instance | |
627 | * @numid: the number-id to search | |
628 | * | |
629 | * Finds the control instance with the given number-id from the card. | |
630 | * | |
1da177e4 LT |
631 | * The caller must down card->controls_rwsem before calling this function |
632 | * (if the race condition can happen). | |
eb7c06e8 YB |
633 | * |
634 | * Return: The pointer of the instance if found, or %NULL if not. | |
635 | * | |
1da177e4 | 636 | */ |
82e9bae6 | 637 | struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid) |
1da177e4 | 638 | { |
82e9bae6 | 639 | struct snd_kcontrol *kctl; |
1da177e4 | 640 | |
7eaa943c TI |
641 | if (snd_BUG_ON(!card || !numid)) |
642 | return NULL; | |
9244b2c3 | 643 | list_for_each_entry(kctl, &card->controls, list) { |
1da177e4 LT |
644 | if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid) |
645 | return kctl; | |
646 | } | |
647 | return NULL; | |
648 | } | |
c0d3fb39 TI |
649 | EXPORT_SYMBOL(snd_ctl_find_numid); |
650 | ||
1da177e4 LT |
651 | /** |
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 | * | |
1da177e4 LT |
658 | * The caller must down card->controls_rwsem before calling this function |
659 | * (if the race condition can happen). | |
eb7c06e8 YB |
660 | * |
661 | * Return: The pointer of the instance if found, or %NULL if not. | |
662 | * | |
1da177e4 | 663 | */ |
82e9bae6 TI |
664 | struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card, |
665 | struct snd_ctl_elem_id *id) | |
1da177e4 | 666 | { |
82e9bae6 | 667 | struct snd_kcontrol *kctl; |
1da177e4 | 668 | |
7eaa943c TI |
669 | if (snd_BUG_ON(!card || !id)) |
670 | return NULL; | |
1da177e4 LT |
671 | if (id->numid != 0) |
672 | return snd_ctl_find_numid(card, id->numid); | |
9244b2c3 | 673 | list_for_each_entry(kctl, &card->controls, list) { |
1da177e4 LT |
674 | 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 | } | |
c0d3fb39 TI |
690 | EXPORT_SYMBOL(snd_ctl_find_id); |
691 | ||
82e9bae6 | 692 | static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl, |
1da177e4 LT |
693 | unsigned int cmd, void __user *arg) |
694 | { | |
82e9bae6 | 695 | struct snd_ctl_card_info *info; |
1da177e4 | 696 | |
ca2c0966 | 697 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
1da177e4 LT |
698 | if (! info) |
699 | return -ENOMEM; | |
700 | down_read(&snd_ioctl_rwsem); | |
701 | info->card = card->number; | |
702 | strlcpy(info->id, card->id, sizeof(info->id)); | |
703 | strlcpy(info->driver, card->driver, sizeof(info->driver)); | |
704 | strlcpy(info->name, card->shortname, sizeof(info->name)); | |
705 | strlcpy(info->longname, card->longname, sizeof(info->longname)); | |
706 | strlcpy(info->mixername, card->mixername, sizeof(info->mixername)); | |
707 | strlcpy(info->components, card->components, sizeof(info->components)); | |
708 | up_read(&snd_ioctl_rwsem); | |
82e9bae6 | 709 | if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) { |
1da177e4 LT |
710 | kfree(info); |
711 | return -EFAULT; | |
712 | } | |
713 | kfree(info); | |
714 | return 0; | |
715 | } | |
716 | ||
82e9bae6 TI |
717 | static int snd_ctl_elem_list(struct snd_card *card, |
718 | struct snd_ctl_elem_list __user *_list) | |
1da177e4 | 719 | { |
82e9bae6 TI |
720 | struct snd_ctl_elem_list list; |
721 | struct snd_kcontrol *kctl; | |
53e7bf45 | 722 | struct snd_ctl_elem_id id; |
78fa2c4d | 723 | unsigned int offset, space, jidx; |
53e7bf45 | 724 | int err = 0; |
dd5f313b | 725 | |
1da177e4 LT |
726 | if (copy_from_user(&list, _list, sizeof(list))) |
727 | return -EFAULT; | |
728 | offset = list.offset; | |
729 | space = list.space; | |
4e361d3c | 730 | |
53e7bf45 TI |
731 | down_read(&card->controls_rwsem); |
732 | list.count = card->controls_count; | |
733 | list.used = 0; | |
1da177e4 | 734 | if (space > 0) { |
53e7bf45 TI |
735 | list_for_each_entry(kctl, &card->controls, list) { |
736 | if (offset >= kctl->count) { | |
737 | offset -= kctl->count; | |
738 | continue; | |
739 | } | |
740 | for (jidx = offset; jidx < kctl->count; jidx++) { | |
741 | snd_ctl_build_ioff(&id, kctl, jidx); | |
742 | if (copy_to_user(list.pids + list.used, &id, | |
743 | sizeof(id))) { | |
744 | err = -EFAULT; | |
745 | goto out; | |
746 | } | |
1da177e4 | 747 | list.used++; |
53e7bf45 TI |
748 | if (!--space) |
749 | goto out; | |
1da177e4 | 750 | } |
1da177e4 LT |
751 | offset = 0; |
752 | } | |
1da177e4 | 753 | } |
53e7bf45 TI |
754 | out: |
755 | up_read(&card->controls_rwsem); | |
756 | if (!err && copy_to_user(_list, &list, sizeof(list))) | |
757 | err = -EFAULT; | |
758 | return err; | |
1da177e4 LT |
759 | } |
760 | ||
860c1994 TS |
761 | static bool validate_element_member_dimension(struct snd_ctl_elem_info *info) |
762 | { | |
763 | unsigned int members; | |
764 | unsigned int i; | |
765 | ||
766 | if (info->dimen.d[0] == 0) | |
767 | return true; | |
768 | ||
769 | members = 1; | |
770 | for (i = 0; i < ARRAY_SIZE(info->dimen.d); ++i) { | |
771 | if (info->dimen.d[i] == 0) | |
772 | break; | |
773 | members *= info->dimen.d[i]; | |
774 | ||
775 | /* | |
776 | * info->count should be validated in advance, to guarantee | |
777 | * calculation soundness. | |
778 | */ | |
779 | if (members > info->count) | |
780 | return false; | |
781 | } | |
782 | ||
783 | for (++i; i < ARRAY_SIZE(info->dimen.d); ++i) { | |
784 | if (info->dimen.d[i] > 0) | |
785 | return false; | |
786 | } | |
787 | ||
788 | return members == info->count; | |
789 | } | |
790 | ||
82e9bae6 TI |
791 | static int snd_ctl_elem_info(struct snd_ctl_file *ctl, |
792 | struct snd_ctl_elem_info *info) | |
1da177e4 | 793 | { |
82e9bae6 TI |
794 | struct snd_card *card = ctl->card; |
795 | struct snd_kcontrol *kctl; | |
796 | struct snd_kcontrol_volatile *vd; | |
1da177e4 LT |
797 | unsigned int index_offset; |
798 | int result; | |
dd5f313b | 799 | |
1da177e4 LT |
800 | down_read(&card->controls_rwsem); |
801 | kctl = snd_ctl_find_id(card, &info->id); | |
802 | if (kctl == NULL) { | |
803 | up_read(&card->controls_rwsem); | |
804 | return -ENOENT; | |
805 | } | |
806 | #ifdef CONFIG_SND_DEBUG | |
807 | info->access = 0; | |
808 | #endif | |
809 | result = kctl->info(kctl, info); | |
810 | if (result >= 0) { | |
7eaa943c | 811 | snd_BUG_ON(info->access); |
1da177e4 LT |
812 | index_offset = snd_ctl_get_ioff(kctl, &info->id); |
813 | vd = &kctl->vd[index_offset]; | |
814 | snd_ctl_build_ioff(&info->id, kctl, index_offset); | |
815 | info->access = vd->access; | |
816 | if (vd->owner) { | |
817 | info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK; | |
818 | if (vd->owner == ctl) | |
819 | info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER; | |
25d27ede | 820 | info->owner = pid_vnr(vd->owner->pid); |
1da177e4 LT |
821 | } else { |
822 | info->owner = -1; | |
823 | } | |
824 | } | |
825 | up_read(&card->controls_rwsem); | |
826 | return result; | |
827 | } | |
828 | ||
82e9bae6 TI |
829 | static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl, |
830 | struct snd_ctl_elem_info __user *_info) | |
1da177e4 | 831 | { |
82e9bae6 | 832 | struct snd_ctl_elem_info info; |
1da177e4 LT |
833 | int result; |
834 | ||
835 | if (copy_from_user(&info, _info, sizeof(info))) | |
836 | return -EFAULT; | |
cbac4b0c | 837 | result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0); |
7d8e8292 TI |
838 | if (result < 0) |
839 | return result; | |
840 | result = snd_ctl_elem_info(ctl, &info); | |
841 | if (result < 0) | |
842 | return result; | |
843 | if (copy_to_user(_info, &info, sizeof(info))) | |
844 | return -EFAULT; | |
1da177e4 LT |
845 | return result; |
846 | } | |
847 | ||
d3bd67cd TI |
848 | static int snd_ctl_elem_read(struct snd_card *card, |
849 | struct snd_ctl_elem_value *control) | |
1da177e4 | 850 | { |
82e9bae6 TI |
851 | struct snd_kcontrol *kctl; |
852 | struct snd_kcontrol_volatile *vd; | |
1da177e4 | 853 | unsigned int index_offset; |
1da177e4 | 854 | |
1da177e4 | 855 | kctl = snd_ctl_find_id(card, &control->id); |
becf9e5d TS |
856 | if (kctl == NULL) |
857 | return -ENOENT; | |
858 | ||
859 | index_offset = snd_ctl_get_ioff(kctl, &control->id); | |
860 | vd = &kctl->vd[index_offset]; | |
5a23699a | 861 | if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_READ) || kctl->get == NULL) |
becf9e5d TS |
862 | return -EPERM; |
863 | ||
864 | snd_ctl_build_ioff(&control->id, kctl, index_offset); | |
865 | return kctl->get(kctl, control); | |
1da177e4 LT |
866 | } |
867 | ||
82e9bae6 TI |
868 | static int snd_ctl_elem_read_user(struct snd_card *card, |
869 | struct snd_ctl_elem_value __user *_control) | |
1da177e4 | 870 | { |
82e9bae6 | 871 | struct snd_ctl_elem_value *control; |
1da177e4 | 872 | int result; |
ef44a1ec LZ |
873 | |
874 | control = memdup_user(_control, sizeof(*control)); | |
875 | if (IS_ERR(control)) | |
876 | return PTR_ERR(control); | |
877 | ||
cbac4b0c | 878 | result = snd_power_wait(card, SNDRV_CTL_POWER_D0); |
7d8e8292 TI |
879 | if (result < 0) |
880 | goto error; | |
881 | ||
882 | down_read(&card->controls_rwsem); | |
883 | result = snd_ctl_elem_read(card, control); | |
884 | up_read(&card->controls_rwsem); | |
885 | if (result < 0) | |
886 | goto error; | |
887 | ||
888 | if (copy_to_user(_control, control, sizeof(*control))) | |
889 | result = -EFAULT; | |
890 | error: | |
1da177e4 LT |
891 | kfree(control); |
892 | return result; | |
893 | } | |
894 | ||
d3bd67cd TI |
895 | static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file, |
896 | struct snd_ctl_elem_value *control) | |
1da177e4 | 897 | { |
82e9bae6 TI |
898 | struct snd_kcontrol *kctl; |
899 | struct snd_kcontrol_volatile *vd; | |
1da177e4 | 900 | unsigned int index_offset; |
8ace4f3c | 901 | int result; |
1da177e4 | 902 | |
1da177e4 | 903 | kctl = snd_ctl_find_id(card, &control->id); |
becf9e5d TS |
904 | if (kctl == NULL) |
905 | return -ENOENT; | |
906 | ||
907 | index_offset = snd_ctl_get_ioff(kctl, &control->id); | |
908 | vd = &kctl->vd[index_offset]; | |
909 | if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) || kctl->put == NULL || | |
910 | (file && vd->owner && vd->owner != file)) { | |
911 | return -EPERM; | |
1da177e4 | 912 | } |
becf9e5d TS |
913 | |
914 | snd_ctl_build_ioff(&control->id, kctl, index_offset); | |
915 | result = kctl->put(kctl, control); | |
916 | if (result < 0) | |
917 | return result; | |
918 | ||
919 | if (result > 0) { | |
920 | struct snd_ctl_elem_id id = control->id; | |
921 | snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, &id); | |
922 | } | |
923 | ||
924 | return 0; | |
1da177e4 LT |
925 | } |
926 | ||
82e9bae6 TI |
927 | static int snd_ctl_elem_write_user(struct snd_ctl_file *file, |
928 | struct snd_ctl_elem_value __user *_control) | |
1da177e4 | 929 | { |
82e9bae6 | 930 | struct snd_ctl_elem_value *control; |
64649400 | 931 | struct snd_card *card; |
1da177e4 LT |
932 | int result; |
933 | ||
ef44a1ec LZ |
934 | control = memdup_user(_control, sizeof(*control)); |
935 | if (IS_ERR(control)) | |
936 | return PTR_ERR(control); | |
937 | ||
64649400 | 938 | card = file->card; |
cbac4b0c | 939 | result = snd_power_wait(card, SNDRV_CTL_POWER_D0); |
7d8e8292 TI |
940 | if (result < 0) |
941 | goto error; | |
942 | ||
943 | down_write(&card->controls_rwsem); | |
944 | result = snd_ctl_elem_write(card, file, control); | |
945 | up_write(&card->controls_rwsem); | |
946 | if (result < 0) | |
947 | goto error; | |
948 | ||
949 | if (copy_to_user(_control, control, sizeof(*control))) | |
950 | result = -EFAULT; | |
951 | error: | |
1da177e4 LT |
952 | kfree(control); |
953 | return result; | |
954 | } | |
955 | ||
82e9bae6 TI |
956 | static int snd_ctl_elem_lock(struct snd_ctl_file *file, |
957 | struct snd_ctl_elem_id __user *_id) | |
1da177e4 | 958 | { |
82e9bae6 TI |
959 | struct snd_card *card = file->card; |
960 | struct snd_ctl_elem_id id; | |
961 | struct snd_kcontrol *kctl; | |
962 | struct snd_kcontrol_volatile *vd; | |
1da177e4 | 963 | int result; |
dd5f313b | 964 | |
1da177e4 LT |
965 | if (copy_from_user(&id, _id, sizeof(id))) |
966 | return -EFAULT; | |
967 | down_write(&card->controls_rwsem); | |
968 | kctl = snd_ctl_find_id(card, &id); | |
969 | if (kctl == NULL) { | |
970 | result = -ENOENT; | |
971 | } else { | |
972 | vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; | |
973 | if (vd->owner != NULL) | |
974 | result = -EBUSY; | |
975 | else { | |
976 | vd->owner = file; | |
1da177e4 LT |
977 | result = 0; |
978 | } | |
979 | } | |
980 | up_write(&card->controls_rwsem); | |
981 | return result; | |
982 | } | |
983 | ||
82e9bae6 TI |
984 | static int snd_ctl_elem_unlock(struct snd_ctl_file *file, |
985 | struct snd_ctl_elem_id __user *_id) | |
1da177e4 | 986 | { |
82e9bae6 TI |
987 | struct snd_card *card = file->card; |
988 | struct snd_ctl_elem_id id; | |
989 | struct snd_kcontrol *kctl; | |
990 | struct snd_kcontrol_volatile *vd; | |
1da177e4 | 991 | int result; |
dd5f313b | 992 | |
1da177e4 LT |
993 | if (copy_from_user(&id, _id, sizeof(id))) |
994 | return -EFAULT; | |
995 | down_write(&card->controls_rwsem); | |
996 | kctl = snd_ctl_find_id(card, &id); | |
997 | if (kctl == NULL) { | |
998 | result = -ENOENT; | |
999 | } else { | |
1000 | vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; | |
1001 | if (vd->owner == NULL) | |
1002 | result = -EINVAL; | |
1003 | else if (vd->owner != file) | |
1004 | result = -EPERM; | |
1005 | else { | |
1006 | vd->owner = NULL; | |
1da177e4 LT |
1007 | result = 0; |
1008 | } | |
1009 | } | |
1010 | up_write(&card->controls_rwsem); | |
1011 | return result; | |
1012 | } | |
1013 | ||
1014 | struct user_element { | |
82e9bae6 | 1015 | struct snd_ctl_elem_info info; |
07f4d9d7 | 1016 | struct snd_card *card; |
e1c78df1 | 1017 | char *elem_data; /* element data */ |
1da177e4 | 1018 | unsigned long elem_data_size; /* size of element data in bytes */ |
8aa9b586 JK |
1019 | void *tlv_data; /* TLV data */ |
1020 | unsigned long tlv_data_size; /* TLV data size */ | |
1da177e4 | 1021 | void *priv_data; /* private data (like strings for enumerated type) */ |
1da177e4 LT |
1022 | }; |
1023 | ||
82e9bae6 TI |
1024 | static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol, |
1025 | struct snd_ctl_elem_info *uinfo) | |
1da177e4 LT |
1026 | { |
1027 | struct user_element *ue = kcontrol->private_data; | |
c378c3b0 | 1028 | unsigned int offset; |
1da177e4 | 1029 | |
c378c3b0 | 1030 | offset = snd_ctl_get_ioff(kcontrol, &uinfo->id); |
1da177e4 | 1031 | *uinfo = ue->info; |
c378c3b0 TS |
1032 | snd_ctl_build_ioff(&uinfo->id, kcontrol, offset); |
1033 | ||
1da177e4 LT |
1034 | return 0; |
1035 | } | |
1036 | ||
8d448162 CL |
1037 | static int snd_ctl_elem_user_enum_info(struct snd_kcontrol *kcontrol, |
1038 | struct snd_ctl_elem_info *uinfo) | |
1039 | { | |
1040 | struct user_element *ue = kcontrol->private_data; | |
1041 | const char *names; | |
1042 | unsigned int item; | |
c378c3b0 | 1043 | unsigned int offset; |
8d448162 CL |
1044 | |
1045 | item = uinfo->value.enumerated.item; | |
1046 | ||
c378c3b0 | 1047 | offset = snd_ctl_get_ioff(kcontrol, &uinfo->id); |
8d448162 | 1048 | *uinfo = ue->info; |
c378c3b0 | 1049 | snd_ctl_build_ioff(&uinfo->id, kcontrol, offset); |
8d448162 CL |
1050 | |
1051 | item = min(item, uinfo->value.enumerated.items - 1); | |
1052 | uinfo->value.enumerated.item = item; | |
1053 | ||
1054 | names = ue->priv_data; | |
1055 | for (; item > 0; --item) | |
1056 | names += strlen(names) + 1; | |
1057 | strcpy(uinfo->value.enumerated.name, names); | |
1058 | ||
1059 | return 0; | |
1060 | } | |
1061 | ||
82e9bae6 TI |
1062 | static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol, |
1063 | struct snd_ctl_elem_value *ucontrol) | |
1da177e4 LT |
1064 | { |
1065 | struct user_element *ue = kcontrol->private_data; | |
e1c78df1 TS |
1066 | unsigned int size = ue->elem_data_size; |
1067 | char *src = ue->elem_data + | |
1068 | snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size; | |
1da177e4 | 1069 | |
e1c78df1 | 1070 | memcpy(&ucontrol->value, src, size); |
1da177e4 LT |
1071 | return 0; |
1072 | } | |
1073 | ||
82e9bae6 TI |
1074 | static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol, |
1075 | struct snd_ctl_elem_value *ucontrol) | |
1da177e4 LT |
1076 | { |
1077 | int change; | |
1078 | struct user_element *ue = kcontrol->private_data; | |
e1c78df1 TS |
1079 | unsigned int size = ue->elem_data_size; |
1080 | char *dst = ue->elem_data + | |
1081 | snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size; | |
07f4d9d7 | 1082 | |
e1c78df1 | 1083 | change = memcmp(&ucontrol->value, dst, size) != 0; |
1da177e4 | 1084 | if (change) |
e1c78df1 | 1085 | memcpy(dst, &ucontrol->value, size); |
1da177e4 LT |
1086 | return change; |
1087 | } | |
1088 | ||
6d4d41f0 TS |
1089 | static int replace_user_tlv(struct snd_kcontrol *kctl, unsigned int __user *buf, |
1090 | unsigned int size) | |
8aa9b586 | 1091 | { |
6d4d41f0 TS |
1092 | struct user_element *ue = kctl->private_data; |
1093 | unsigned int *container; | |
da428828 | 1094 | struct snd_ctl_elem_id id; |
b8e2204b | 1095 | unsigned int mask = 0; |
da428828 | 1096 | int i; |
6d4d41f0 | 1097 | int change; |
8aa9b586 | 1098 | |
6d4d41f0 TS |
1099 | if (size > 1024 * 128) /* sane value */ |
1100 | return -EINVAL; | |
30d8340b | 1101 | |
88a89037 | 1102 | container = vmemdup_user(buf, size); |
6d4d41f0 TS |
1103 | if (IS_ERR(container)) |
1104 | return PTR_ERR(container); | |
ef44a1ec | 1105 | |
6d4d41f0 TS |
1106 | change = ue->tlv_data_size != size; |
1107 | if (!change) | |
241bc82e | 1108 | change = memcmp(ue->tlv_data, container, size) != 0; |
6d4d41f0 | 1109 | if (!change) { |
88a89037 | 1110 | kvfree(container); |
6d4d41f0 TS |
1111 | return 0; |
1112 | } | |
30d8340b | 1113 | |
b8e2204b TS |
1114 | if (ue->tlv_data == NULL) { |
1115 | /* Now TLV data is available. */ | |
1116 | for (i = 0; i < kctl->count; ++i) | |
1117 | kctl->vd[i].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ; | |
1118 | mask = SNDRV_CTL_EVENT_MASK_INFO; | |
1119 | } | |
1120 | ||
88a89037 | 1121 | kvfree(ue->tlv_data); |
6d4d41f0 TS |
1122 | ue->tlv_data = container; |
1123 | ue->tlv_data_size = size; | |
07f4d9d7 | 1124 | |
b8e2204b | 1125 | mask |= SNDRV_CTL_EVENT_MASK_TLV; |
da428828 TS |
1126 | for (i = 0; i < kctl->count; ++i) { |
1127 | snd_ctl_build_ioff(&id, kctl, i); | |
b8e2204b | 1128 | snd_ctl_notify(ue->card, mask, &id); |
da428828 | 1129 | } |
fb8027eb | 1130 | |
6d4d41f0 TS |
1131 | return change; |
1132 | } | |
30d8340b | 1133 | |
6d4d41f0 TS |
1134 | static int read_user_tlv(struct snd_kcontrol *kctl, unsigned int __user *buf, |
1135 | unsigned int size) | |
1136 | { | |
1137 | struct user_element *ue = kctl->private_data; | |
1138 | ||
1139 | if (ue->tlv_data_size == 0 || ue->tlv_data == NULL) | |
1140 | return -ENXIO; | |
1141 | ||
1142 | if (size < ue->tlv_data_size) | |
1143 | return -ENOSPC; | |
1144 | ||
1145 | if (copy_to_user(buf, ue->tlv_data, ue->tlv_data_size)) | |
1146 | return -EFAULT; | |
1147 | ||
1148 | return 0; | |
1149 | } | |
1150 | ||
1151 | static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kctl, int op_flag, | |
1152 | unsigned int size, unsigned int __user *buf) | |
1153 | { | |
1154 | if (op_flag == SNDRV_CTL_TLV_OP_WRITE) | |
1155 | return replace_user_tlv(kctl, buf, size); | |
1156 | else | |
1157 | return read_user_tlv(kctl, buf, size); | |
8aa9b586 JK |
1158 | } |
1159 | ||
8d448162 CL |
1160 | static int snd_ctl_elem_init_enum_names(struct user_element *ue) |
1161 | { | |
1162 | char *names, *p; | |
1163 | size_t buf_len, name_len; | |
1164 | unsigned int i; | |
447c6f93 | 1165 | const uintptr_t user_ptrval = ue->info.value.enumerated.names_ptr; |
8d448162 CL |
1166 | |
1167 | if (ue->info.value.enumerated.names_length > 64 * 1024) | |
1168 | return -EINVAL; | |
1169 | ||
59aeaf3f | 1170 | names = vmemdup_user((const void __user *)user_ptrval, |
8d448162 CL |
1171 | ue->info.value.enumerated.names_length); |
1172 | if (IS_ERR(names)) | |
1173 | return PTR_ERR(names); | |
1174 | ||
1175 | /* check that there are enough valid names */ | |
1176 | buf_len = ue->info.value.enumerated.names_length; | |
1177 | p = names; | |
1178 | for (i = 0; i < ue->info.value.enumerated.items; ++i) { | |
1179 | name_len = strnlen(p, buf_len); | |
1180 | if (name_len == 0 || name_len >= 64 || name_len == buf_len) { | |
59aeaf3f | 1181 | kvfree(names); |
8d448162 CL |
1182 | return -EINVAL; |
1183 | } | |
1184 | p += name_len + 1; | |
1185 | buf_len -= name_len + 1; | |
1186 | } | |
1187 | ||
1188 | ue->priv_data = names; | |
1189 | ue->info.value.enumerated.names_ptr = 0; | |
1190 | ||
1191 | return 0; | |
1192 | } | |
1193 | ||
82e9bae6 | 1194 | static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol) |
1da177e4 | 1195 | { |
8aa9b586 | 1196 | struct user_element *ue = kcontrol->private_data; |
8d448162 | 1197 | |
88a89037 | 1198 | kvfree(ue->tlv_data); |
59aeaf3f | 1199 | kvfree(ue->priv_data); |
8aa9b586 | 1200 | kfree(ue); |
1da177e4 LT |
1201 | } |
1202 | ||
82e9bae6 TI |
1203 | static int snd_ctl_elem_add(struct snd_ctl_file *file, |
1204 | struct snd_ctl_elem_info *info, int replace) | |
1da177e4 | 1205 | { |
4ed56666 TS |
1206 | /* The capacity of struct snd_ctl_elem_value.value.*/ |
1207 | static const unsigned int value_sizes[] = { | |
1208 | [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = sizeof(long), | |
1209 | [SNDRV_CTL_ELEM_TYPE_INTEGER] = sizeof(long), | |
1210 | [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = sizeof(unsigned int), | |
1211 | [SNDRV_CTL_ELEM_TYPE_BYTES] = sizeof(unsigned char), | |
1212 | [SNDRV_CTL_ELEM_TYPE_IEC958] = sizeof(struct snd_aes_iec958), | |
1213 | [SNDRV_CTL_ELEM_TYPE_INTEGER64] = sizeof(long long), | |
1214 | }; | |
1215 | static const unsigned int max_value_counts[] = { | |
1216 | [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = 128, | |
1217 | [SNDRV_CTL_ELEM_TYPE_INTEGER] = 128, | |
1218 | [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = 128, | |
1219 | [SNDRV_CTL_ELEM_TYPE_BYTES] = 512, | |
1220 | [SNDRV_CTL_ELEM_TYPE_IEC958] = 1, | |
1221 | [SNDRV_CTL_ELEM_TYPE_INTEGER64] = 64, | |
1222 | }; | |
82e9bae6 | 1223 | struct snd_card *card = file->card; |
2225e79b TS |
1224 | struct snd_kcontrol *kctl; |
1225 | unsigned int count; | |
1da177e4 LT |
1226 | unsigned int access; |
1227 | long private_size; | |
1228 | struct user_element *ue; | |
cab2ed74 | 1229 | unsigned int offset; |
2225e79b | 1230 | int err; |
82262a46 | 1231 | |
be3bb823 TI |
1232 | if (!*info->id.name) |
1233 | return -EINVAL; | |
1234 | if (strnlen(info->id.name, sizeof(info->id.name)) >= sizeof(info->id.name)) | |
1235 | return -EINVAL; | |
82262a46 | 1236 | |
2225e79b | 1237 | /* Delete a control to replace them if needed. */ |
82262a46 | 1238 | if (replace) { |
2225e79b | 1239 | info->id.numid = 0; |
82262a46 LPC |
1240 | err = snd_ctl_remove_user_ctl(file, &info->id); |
1241 | if (err) | |
1242 | return err; | |
1da177e4 | 1243 | } |
82262a46 | 1244 | |
2225e79b TS |
1245 | /* |
1246 | * The number of userspace controls are counted control by control, | |
1247 | * not element by element. | |
1248 | */ | |
1249 | if (card->user_ctl_count + 1 > MAX_USER_CONTROLS) | |
82262a46 LPC |
1250 | return -ENOMEM; |
1251 | ||
2225e79b TS |
1252 | /* Check the number of elements for this userspace control. */ |
1253 | count = info->owner; | |
1254 | if (count == 0) | |
1255 | count = 1; | |
1256 | ||
1257 | /* Arrange access permissions if needed. */ | |
1258 | access = info->access; | |
1259 | if (access == 0) | |
1260 | access = SNDRV_CTL_ELEM_ACCESS_READWRITE; | |
1261 | access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE | | |
1262 | SNDRV_CTL_ELEM_ACCESS_INACTIVE | | |
b8e2204b TS |
1263 | SNDRV_CTL_ELEM_ACCESS_TLV_WRITE); |
1264 | ||
1265 | /* In initial state, nothing is available as TLV container. */ | |
1266 | if (access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) | |
8aa9b586 | 1267 | access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK; |
2225e79b | 1268 | access |= SNDRV_CTL_ELEM_ACCESS_USER; |
4ed56666 | 1269 | |
2225e79b TS |
1270 | /* |
1271 | * Check information and calculate the size of data specific to | |
1272 | * this userspace control. | |
1273 | */ | |
4ed56666 TS |
1274 | if (info->type < SNDRV_CTL_ELEM_TYPE_BOOLEAN || |
1275 | info->type > SNDRV_CTL_ELEM_TYPE_INTEGER64) | |
1da177e4 | 1276 | return -EINVAL; |
4ed56666 TS |
1277 | if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED && |
1278 | info->value.enumerated.items == 0) | |
1279 | return -EINVAL; | |
1280 | if (info->count < 1 || | |
1281 | info->count > max_value_counts[info->type]) | |
1282 | return -EINVAL; | |
860c1994 TS |
1283 | if (!validate_element_member_dimension(info)) |
1284 | return -EINVAL; | |
4ed56666 | 1285 | private_size = value_sizes[info->type] * info->count; |
2225e79b TS |
1286 | |
1287 | /* | |
1288 | * Keep memory object for this userspace control. After passing this | |
1289 | * code block, the instance should be freed by snd_ctl_free_one(). | |
1290 | * | |
1291 | * Note that these elements in this control are locked. | |
1292 | */ | |
1293 | err = snd_ctl_new(&kctl, count, access, file); | |
1294 | if (err < 0) | |
1295 | return err; | |
e79d74ab | 1296 | memcpy(&kctl->id, &info->id, sizeof(kctl->id)); |
e1c78df1 | 1297 | kctl->private_data = kzalloc(sizeof(struct user_element) + private_size * count, |
2225e79b TS |
1298 | GFP_KERNEL); |
1299 | if (kctl->private_data == NULL) { | |
1300 | kfree(kctl); | |
1da177e4 | 1301 | return -ENOMEM; |
2225e79b TS |
1302 | } |
1303 | kctl->private_free = snd_ctl_elem_user_free; | |
1304 | ||
1305 | /* Set private data for this userspace control. */ | |
1306 | ue = (struct user_element *)kctl->private_data; | |
07f4d9d7 | 1307 | ue->card = card; |
1da177e4 | 1308 | ue->info = *info; |
86148e84 | 1309 | ue->info.access = 0; |
1da177e4 LT |
1310 | ue->elem_data = (char *)ue + sizeof(*ue); |
1311 | ue->elem_data_size = private_size; | |
8d448162 CL |
1312 | if (ue->info.type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) { |
1313 | err = snd_ctl_elem_init_enum_names(ue); | |
1314 | if (err < 0) { | |
2225e79b | 1315 | snd_ctl_free_one(kctl); |
8d448162 CL |
1316 | return err; |
1317 | } | |
1318 | } | |
2225e79b TS |
1319 | |
1320 | /* Set callback functions. */ | |
1321 | if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) | |
1322 | kctl->info = snd_ctl_elem_user_enum_info; | |
1323 | else | |
1324 | kctl->info = snd_ctl_elem_user_info; | |
1325 | if (access & SNDRV_CTL_ELEM_ACCESS_READ) | |
1326 | kctl->get = snd_ctl_elem_user_get; | |
1327 | if (access & SNDRV_CTL_ELEM_ACCESS_WRITE) | |
1328 | kctl->put = snd_ctl_elem_user_put; | |
b8e2204b | 1329 | if (access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) |
2225e79b TS |
1330 | kctl->tlv.c = snd_ctl_elem_user_tlv; |
1331 | ||
1332 | /* This function manage to free the instance on failure. */ | |
e1a7bfe3 | 1333 | down_write(&card->controls_rwsem); |
3103c08f | 1334 | err = __snd_ctl_add_replace(card, kctl, CTL_ADD_EXCLUSIVE); |
e1a7bfe3 TI |
1335 | if (err < 0) { |
1336 | snd_ctl_free_one(kctl); | |
1337 | goto unlock; | |
1338 | } | |
cab2ed74 TS |
1339 | offset = snd_ctl_get_ioff(kctl, &info->id); |
1340 | snd_ctl_build_ioff(&info->id, kctl, offset); | |
1341 | /* | |
1342 | * Here we cannot fill any field for the number of elements added by | |
1343 | * this operation because there're no specific fields. The usage of | |
1344 | * 'owner' field for this purpose may cause any bugs to userspace | |
1345 | * applications because the field originally means PID of a process | |
1346 | * which locks the element. | |
1347 | */ | |
1da177e4 | 1348 | |
1da177e4 | 1349 | card->user_ctl_count++; |
1da177e4 | 1350 | |
e1a7bfe3 TI |
1351 | unlock: |
1352 | up_write(&card->controls_rwsem); | |
1da177e4 LT |
1353 | return 0; |
1354 | } | |
1355 | ||
82e9bae6 TI |
1356 | static int snd_ctl_elem_add_user(struct snd_ctl_file *file, |
1357 | struct snd_ctl_elem_info __user *_info, int replace) | |
1da177e4 | 1358 | { |
82e9bae6 | 1359 | struct snd_ctl_elem_info info; |
cab2ed74 TS |
1360 | int err; |
1361 | ||
1da177e4 LT |
1362 | if (copy_from_user(&info, _info, sizeof(info))) |
1363 | return -EFAULT; | |
cab2ed74 TS |
1364 | err = snd_ctl_elem_add(file, &info, replace); |
1365 | if (err < 0) | |
1366 | return err; | |
1367 | if (copy_to_user(_info, &info, sizeof(info))) { | |
1368 | snd_ctl_remove_user_ctl(file, &info.id); | |
1369 | return -EFAULT; | |
1370 | } | |
1371 | ||
1372 | return 0; | |
1da177e4 LT |
1373 | } |
1374 | ||
82e9bae6 TI |
1375 | static int snd_ctl_elem_remove(struct snd_ctl_file *file, |
1376 | struct snd_ctl_elem_id __user *_id) | |
1da177e4 | 1377 | { |
82e9bae6 | 1378 | struct snd_ctl_elem_id id; |
1da177e4 LT |
1379 | |
1380 | if (copy_from_user(&id, _id, sizeof(id))) | |
1381 | return -EFAULT; | |
f217ac59 | 1382 | return snd_ctl_remove_user_ctl(file, &id); |
1da177e4 LT |
1383 | } |
1384 | ||
82e9bae6 | 1385 | static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr) |
1da177e4 LT |
1386 | { |
1387 | int subscribe; | |
1388 | if (get_user(subscribe, ptr)) | |
1389 | return -EFAULT; | |
1390 | if (subscribe < 0) { | |
1391 | subscribe = file->subscribed; | |
1392 | if (put_user(subscribe, ptr)) | |
1393 | return -EFAULT; | |
1394 | return 0; | |
1395 | } | |
1396 | if (subscribe) { | |
1397 | file->subscribed = 1; | |
1398 | return 0; | |
1399 | } else if (file->subscribed) { | |
1400 | snd_ctl_empty_read_queue(file); | |
1401 | file->subscribed = 0; | |
1402 | } | |
1403 | return 0; | |
1404 | } | |
1405 | ||
450296f3 TS |
1406 | static int call_tlv_handler(struct snd_ctl_file *file, int op_flag, |
1407 | struct snd_kcontrol *kctl, | |
1408 | struct snd_ctl_elem_id *id, | |
1409 | unsigned int __user *buf, unsigned int size) | |
1410 | { | |
1411 | static const struct { | |
1412 | int op; | |
1413 | int perm; | |
1414 | } pairs[] = { | |
1415 | {SNDRV_CTL_TLV_OP_READ, SNDRV_CTL_ELEM_ACCESS_TLV_READ}, | |
1416 | {SNDRV_CTL_TLV_OP_WRITE, SNDRV_CTL_ELEM_ACCESS_TLV_WRITE}, | |
1417 | {SNDRV_CTL_TLV_OP_CMD, SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND}, | |
1418 | }; | |
1419 | struct snd_kcontrol_volatile *vd = &kctl->vd[snd_ctl_get_ioff(kctl, id)]; | |
1420 | int i; | |
450296f3 TS |
1421 | |
1422 | /* Check support of the request for this element. */ | |
1423 | for (i = 0; i < ARRAY_SIZE(pairs); ++i) { | |
1424 | if (op_flag == pairs[i].op && (vd->access & pairs[i].perm)) | |
1425 | break; | |
1426 | } | |
1427 | if (i == ARRAY_SIZE(pairs)) | |
1428 | return -ENXIO; | |
1429 | ||
1430 | if (kctl->tlv.c == NULL) | |
1431 | return -ENXIO; | |
1432 | ||
1433 | /* When locked, this is unavailable. */ | |
1434 | if (vd->owner != NULL && vd->owner != file) | |
1435 | return -EPERM; | |
1436 | ||
fb8027eb | 1437 | return kctl->tlv.c(kctl, op_flag, size, buf); |
450296f3 TS |
1438 | } |
1439 | ||
1440 | static int read_tlv_buf(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id, | |
1441 | unsigned int __user *buf, unsigned int size) | |
1442 | { | |
1443 | struct snd_kcontrol_volatile *vd = &kctl->vd[snd_ctl_get_ioff(kctl, id)]; | |
1444 | unsigned int len; | |
1445 | ||
1446 | if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ)) | |
1447 | return -ENXIO; | |
1448 | ||
1449 | if (kctl->tlv.p == NULL) | |
1450 | return -ENXIO; | |
1451 | ||
1452 | len = sizeof(unsigned int) * 2 + kctl->tlv.p[1]; | |
1453 | if (size < len) | |
1454 | return -ENOMEM; | |
1455 | ||
1456 | if (copy_to_user(buf, kctl->tlv.p, len)) | |
1457 | return -EFAULT; | |
1458 | ||
1459 | return 0; | |
1460 | } | |
1461 | ||
8aa9b586 | 1462 | static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file, |
450296f3 | 1463 | struct snd_ctl_tlv __user *buf, |
8aa9b586 | 1464 | int op_flag) |
42750b04 | 1465 | { |
450296f3 | 1466 | struct snd_ctl_tlv header; |
1ba7862f | 1467 | unsigned int __user *container; |
450296f3 | 1468 | unsigned int container_size; |
42750b04 | 1469 | struct snd_kcontrol *kctl; |
450296f3 | 1470 | struct snd_ctl_elem_id id; |
8aa9b586 | 1471 | struct snd_kcontrol_volatile *vd; |
42750b04 | 1472 | |
450296f3 | 1473 | if (copy_from_user(&header, buf, sizeof(header))) |
42750b04 | 1474 | return -EFAULT; |
450296f3 TS |
1475 | |
1476 | /* In design of control core, numerical ID starts at 1. */ | |
1477 | if (header.numid == 0) | |
8aa9b586 | 1478 | return -EINVAL; |
450296f3 TS |
1479 | |
1480 | /* At least, container should include type and length fields. */ | |
1481 | if (header.length < sizeof(unsigned int) * 2) | |
c0bcdbdf | 1482 | return -EINVAL; |
450296f3 TS |
1483 | container_size = header.length; |
1484 | container = buf->tlv; | |
4c8099e9 | 1485 | |
450296f3 | 1486 | kctl = snd_ctl_find_numid(file->card, header.numid); |
4c8099e9 TS |
1487 | if (kctl == NULL) |
1488 | return -ENOENT; | |
1489 | ||
450296f3 TS |
1490 | /* Calculate index of the element in this set. */ |
1491 | id = kctl->id; | |
1492 | snd_ctl_build_ioff(&id, kctl, header.numid - id.numid); | |
1493 | vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; | |
4c8099e9 | 1494 | |
8aa9b586 | 1495 | if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) { |
450296f3 TS |
1496 | return call_tlv_handler(file, op_flag, kctl, &id, container, |
1497 | container_size); | |
8aa9b586 | 1498 | } else { |
450296f3 TS |
1499 | if (op_flag == SNDRV_CTL_TLV_OP_READ) { |
1500 | return read_tlv_buf(kctl, &id, container, | |
1501 | container_size); | |
1502 | } | |
8aa9b586 | 1503 | } |
4c8099e9 | 1504 | |
450296f3 TS |
1505 | /* Not supported. */ |
1506 | return -ENXIO; | |
42750b04 JK |
1507 | } |
1508 | ||
1da177e4 LT |
1509 | static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
1510 | { | |
82e9bae6 TI |
1511 | struct snd_ctl_file *ctl; |
1512 | struct snd_card *card; | |
82e9bae6 | 1513 | struct snd_kctl_ioctl *p; |
1da177e4 LT |
1514 | void __user *argp = (void __user *)arg; |
1515 | int __user *ip = argp; | |
1516 | int err; | |
1517 | ||
1518 | ctl = file->private_data; | |
1519 | card = ctl->card; | |
7eaa943c TI |
1520 | if (snd_BUG_ON(!card)) |
1521 | return -ENXIO; | |
1da177e4 LT |
1522 | switch (cmd) { |
1523 | case SNDRV_CTL_IOCTL_PVERSION: | |
1524 | return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0; | |
1525 | case SNDRV_CTL_IOCTL_CARD_INFO: | |
1526 | return snd_ctl_card_info(card, ctl, cmd, argp); | |
1527 | case SNDRV_CTL_IOCTL_ELEM_LIST: | |
42750b04 | 1528 | return snd_ctl_elem_list(card, argp); |
1da177e4 LT |
1529 | case SNDRV_CTL_IOCTL_ELEM_INFO: |
1530 | return snd_ctl_elem_info_user(ctl, argp); | |
1531 | case SNDRV_CTL_IOCTL_ELEM_READ: | |
42750b04 | 1532 | return snd_ctl_elem_read_user(card, argp); |
1da177e4 LT |
1533 | case SNDRV_CTL_IOCTL_ELEM_WRITE: |
1534 | return snd_ctl_elem_write_user(ctl, argp); | |
1535 | case SNDRV_CTL_IOCTL_ELEM_LOCK: | |
1536 | return snd_ctl_elem_lock(ctl, argp); | |
1537 | case SNDRV_CTL_IOCTL_ELEM_UNLOCK: | |
1538 | return snd_ctl_elem_unlock(ctl, argp); | |
1539 | case SNDRV_CTL_IOCTL_ELEM_ADD: | |
1540 | return snd_ctl_elem_add_user(ctl, argp, 0); | |
1541 | case SNDRV_CTL_IOCTL_ELEM_REPLACE: | |
1542 | return snd_ctl_elem_add_user(ctl, argp, 1); | |
1543 | case SNDRV_CTL_IOCTL_ELEM_REMOVE: | |
1544 | return snd_ctl_elem_remove(ctl, argp); | |
1545 | case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS: | |
1546 | return snd_ctl_subscribe_events(ctl, ip); | |
8aa9b586 | 1547 | case SNDRV_CTL_IOCTL_TLV_READ: |
4c8099e9 TS |
1548 | down_read(&ctl->card->controls_rwsem); |
1549 | err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_READ); | |
1550 | up_read(&ctl->card->controls_rwsem); | |
1551 | return err; | |
8aa9b586 | 1552 | case SNDRV_CTL_IOCTL_TLV_WRITE: |
4c8099e9 TS |
1553 | down_write(&ctl->card->controls_rwsem); |
1554 | err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_WRITE); | |
1555 | up_write(&ctl->card->controls_rwsem); | |
1556 | return err; | |
8aa9b586 | 1557 | case SNDRV_CTL_IOCTL_TLV_COMMAND: |
4c8099e9 TS |
1558 | down_write(&ctl->card->controls_rwsem); |
1559 | err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_CMD); | |
1560 | up_write(&ctl->card->controls_rwsem); | |
1561 | return err; | |
1da177e4 | 1562 | case SNDRV_CTL_IOCTL_POWER: |
a381a7a6 | 1563 | return -ENOPROTOOPT; |
1da177e4 LT |
1564 | case SNDRV_CTL_IOCTL_POWER_STATE: |
1565 | #ifdef CONFIG_PM | |
1566 | return put_user(card->power_state, ip) ? -EFAULT : 0; | |
1567 | #else | |
1568 | return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0; | |
1569 | #endif | |
1570 | } | |
1571 | down_read(&snd_ioctl_rwsem); | |
9244b2c3 | 1572 | list_for_each_entry(p, &snd_control_ioctls, list) { |
1da177e4 LT |
1573 | err = p->fioctl(card, ctl, cmd, arg); |
1574 | if (err != -ENOIOCTLCMD) { | |
1575 | up_read(&snd_ioctl_rwsem); | |
1576 | return err; | |
1577 | } | |
1578 | } | |
1579 | up_read(&snd_ioctl_rwsem); | |
bb009457 | 1580 | dev_dbg(card->dev, "unknown ioctl = 0x%x\n", cmd); |
1da177e4 LT |
1581 | return -ENOTTY; |
1582 | } | |
1583 | ||
82e9bae6 TI |
1584 | static ssize_t snd_ctl_read(struct file *file, char __user *buffer, |
1585 | size_t count, loff_t * offset) | |
1da177e4 | 1586 | { |
82e9bae6 | 1587 | struct snd_ctl_file *ctl; |
1da177e4 LT |
1588 | int err = 0; |
1589 | ssize_t result = 0; | |
1590 | ||
1591 | ctl = file->private_data; | |
7eaa943c TI |
1592 | if (snd_BUG_ON(!ctl || !ctl->card)) |
1593 | return -ENXIO; | |
1da177e4 LT |
1594 | if (!ctl->subscribed) |
1595 | return -EBADFD; | |
82e9bae6 | 1596 | if (count < sizeof(struct snd_ctl_event)) |
1da177e4 LT |
1597 | return -EINVAL; |
1598 | spin_lock_irq(&ctl->read_lock); | |
82e9bae6 TI |
1599 | while (count >= sizeof(struct snd_ctl_event)) { |
1600 | struct snd_ctl_event ev; | |
1601 | struct snd_kctl_event *kev; | |
1da177e4 | 1602 | while (list_empty(&ctl->events)) { |
ac6424b9 | 1603 | wait_queue_entry_t wait; |
1da177e4 LT |
1604 | if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) { |
1605 | err = -EAGAIN; | |
1606 | goto __end_lock; | |
1607 | } | |
1608 | init_waitqueue_entry(&wait, current); | |
1609 | add_wait_queue(&ctl->change_sleep, &wait); | |
1610 | set_current_state(TASK_INTERRUPTIBLE); | |
1611 | spin_unlock_irq(&ctl->read_lock); | |
1612 | schedule(); | |
1613 | remove_wait_queue(&ctl->change_sleep, &wait); | |
0914f796 TI |
1614 | if (ctl->card->shutdown) |
1615 | return -ENODEV; | |
1da177e4 | 1616 | if (signal_pending(current)) |
0e5d720c | 1617 | return -ERESTARTSYS; |
1da177e4 LT |
1618 | spin_lock_irq(&ctl->read_lock); |
1619 | } | |
1620 | kev = snd_kctl_event(ctl->events.next); | |
1621 | ev.type = SNDRV_CTL_EVENT_ELEM; | |
1622 | ev.data.elem.mask = kev->mask; | |
1623 | ev.data.elem.id = kev->id; | |
1624 | list_del(&kev->list); | |
1625 | spin_unlock_irq(&ctl->read_lock); | |
1626 | kfree(kev); | |
82e9bae6 | 1627 | if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) { |
1da177e4 LT |
1628 | err = -EFAULT; |
1629 | goto __end; | |
1630 | } | |
1631 | spin_lock_irq(&ctl->read_lock); | |
82e9bae6 TI |
1632 | buffer += sizeof(struct snd_ctl_event); |
1633 | count -= sizeof(struct snd_ctl_event); | |
1634 | result += sizeof(struct snd_ctl_event); | |
1da177e4 LT |
1635 | } |
1636 | __end_lock: | |
1637 | spin_unlock_irq(&ctl->read_lock); | |
1638 | __end: | |
1639 | return result > 0 ? result : err; | |
1640 | } | |
1641 | ||
680ef72a | 1642 | static __poll_t snd_ctl_poll(struct file *file, poll_table * wait) |
1da177e4 | 1643 | { |
680ef72a | 1644 | __poll_t mask; |
82e9bae6 | 1645 | struct snd_ctl_file *ctl; |
1da177e4 LT |
1646 | |
1647 | ctl = file->private_data; | |
1648 | if (!ctl->subscribed) | |
1649 | return 0; | |
1650 | poll_wait(file, &ctl->change_sleep, wait); | |
1651 | ||
1652 | mask = 0; | |
1653 | if (!list_empty(&ctl->events)) | |
a9a08845 | 1654 | mask |= EPOLLIN | EPOLLRDNORM; |
1da177e4 LT |
1655 | |
1656 | return mask; | |
1657 | } | |
1658 | ||
1659 | /* | |
1660 | * register the device-specific control-ioctls. | |
1661 | * called from each device manager like pcm.c, hwdep.c, etc. | |
1662 | */ | |
1663 | static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists) | |
1664 | { | |
82e9bae6 | 1665 | struct snd_kctl_ioctl *pn; |
1da177e4 | 1666 | |
82e9bae6 | 1667 | pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL); |
1da177e4 LT |
1668 | if (pn == NULL) |
1669 | return -ENOMEM; | |
1670 | pn->fioctl = fcn; | |
1671 | down_write(&snd_ioctl_rwsem); | |
1672 | list_add_tail(&pn->list, lists); | |
1673 | up_write(&snd_ioctl_rwsem); | |
1674 | return 0; | |
1675 | } | |
1676 | ||
12cddbd8 TI |
1677 | /** |
1678 | * snd_ctl_register_ioctl - register the device-specific control-ioctls | |
1679 | * @fcn: ioctl callback function | |
1680 | * | |
1681 | * called from each device manager like pcm.c, hwdep.c, etc. | |
1682 | */ | |
1da177e4 LT |
1683 | int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn) |
1684 | { | |
1685 | return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls); | |
1686 | } | |
c0d3fb39 TI |
1687 | EXPORT_SYMBOL(snd_ctl_register_ioctl); |
1688 | ||
1da177e4 | 1689 | #ifdef CONFIG_COMPAT |
12cddbd8 TI |
1690 | /** |
1691 | * snd_ctl_register_ioctl_compat - register the device-specific 32bit compat | |
1692 | * control-ioctls | |
1693 | * @fcn: ioctl callback function | |
1694 | */ | |
1da177e4 LT |
1695 | int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn) |
1696 | { | |
1697 | return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls); | |
1698 | } | |
c0d3fb39 | 1699 | EXPORT_SYMBOL(snd_ctl_register_ioctl_compat); |
1da177e4 LT |
1700 | #endif |
1701 | ||
1702 | /* | |
1703 | * de-register the device-specific control-ioctls. | |
1704 | */ | |
82e9bae6 TI |
1705 | static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn, |
1706 | struct list_head *lists) | |
1da177e4 | 1707 | { |
82e9bae6 | 1708 | struct snd_kctl_ioctl *p; |
1da177e4 | 1709 | |
7eaa943c TI |
1710 | if (snd_BUG_ON(!fcn)) |
1711 | return -EINVAL; | |
1da177e4 | 1712 | down_write(&snd_ioctl_rwsem); |
9244b2c3 | 1713 | list_for_each_entry(p, lists, list) { |
1da177e4 LT |
1714 | if (p->fioctl == fcn) { |
1715 | list_del(&p->list); | |
1716 | up_write(&snd_ioctl_rwsem); | |
1717 | kfree(p); | |
1718 | return 0; | |
1719 | } | |
1720 | } | |
1721 | up_write(&snd_ioctl_rwsem); | |
1722 | snd_BUG(); | |
1723 | return -EINVAL; | |
1724 | } | |
1725 | ||
12cddbd8 TI |
1726 | /** |
1727 | * snd_ctl_unregister_ioctl - de-register the device-specific control-ioctls | |
1728 | * @fcn: ioctl callback function to unregister | |
1729 | */ | |
1da177e4 LT |
1730 | int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn) |
1731 | { | |
1732 | return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls); | |
1733 | } | |
c0d3fb39 TI |
1734 | EXPORT_SYMBOL(snd_ctl_unregister_ioctl); |
1735 | ||
1da177e4 | 1736 | #ifdef CONFIG_COMPAT |
12cddbd8 TI |
1737 | /** |
1738 | * snd_ctl_unregister_ioctl - de-register the device-specific compat 32bit | |
1739 | * control-ioctls | |
1740 | * @fcn: ioctl callback function to unregister | |
1741 | */ | |
1da177e4 LT |
1742 | int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn) |
1743 | { | |
1744 | return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls); | |
1745 | } | |
c0d3fb39 | 1746 | EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat); |
1da177e4 LT |
1747 | #endif |
1748 | ||
1749 | static int snd_ctl_fasync(int fd, struct file * file, int on) | |
1750 | { | |
82e9bae6 | 1751 | struct snd_ctl_file *ctl; |
60aa4924 | 1752 | |
1da177e4 | 1753 | ctl = file->private_data; |
60aa4924 | 1754 | return fasync_helper(fd, file, on, &ctl->fasync); |
1da177e4 LT |
1755 | } |
1756 | ||
23c18d4b TI |
1757 | /* return the preferred subdevice number if already assigned; |
1758 | * otherwise return -1 | |
1759 | */ | |
1760 | int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type) | |
1761 | { | |
1762 | struct snd_ctl_file *kctl; | |
1763 | int subdevice = -1; | |
1764 | ||
1765 | read_lock(&card->ctl_files_rwlock); | |
1766 | list_for_each_entry(kctl, &card->ctl_files, list) { | |
1767 | if (kctl->pid == task_pid(current)) { | |
1768 | subdevice = kctl->preferred_subdevice[type]; | |
1769 | if (subdevice != -1) | |
1770 | break; | |
1771 | } | |
1772 | } | |
1773 | read_unlock(&card->ctl_files_rwlock); | |
1774 | return subdevice; | |
1775 | } | |
1776 | EXPORT_SYMBOL_GPL(snd_ctl_get_preferred_subdevice); | |
1777 | ||
1da177e4 LT |
1778 | /* |
1779 | * ioctl32 compat | |
1780 | */ | |
1781 | #ifdef CONFIG_COMPAT | |
1782 | #include "control_compat.c" | |
1783 | #else | |
1784 | #define snd_ctl_ioctl_compat NULL | |
1785 | #endif | |
1786 | ||
1787 | /* | |
1788 | * INIT PART | |
1789 | */ | |
1790 | ||
9c2e08c5 | 1791 | static const struct file_operations snd_ctl_f_ops = |
1da177e4 LT |
1792 | { |
1793 | .owner = THIS_MODULE, | |
1794 | .read = snd_ctl_read, | |
1795 | .open = snd_ctl_open, | |
1796 | .release = snd_ctl_release, | |
02f4865f | 1797 | .llseek = no_llseek, |
1da177e4 LT |
1798 | .poll = snd_ctl_poll, |
1799 | .unlocked_ioctl = snd_ctl_ioctl, | |
1800 | .compat_ioctl = snd_ctl_ioctl_compat, | |
1801 | .fasync = snd_ctl_fasync, | |
1802 | }; | |
1803 | ||
1da177e4 LT |
1804 | /* |
1805 | * registration of the control device | |
1806 | */ | |
82e9bae6 | 1807 | static int snd_ctl_dev_register(struct snd_device *device) |
1da177e4 | 1808 | { |
82e9bae6 | 1809 | struct snd_card *card = device->device_data; |
1da177e4 | 1810 | |
40a4b263 TI |
1811 | return snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1, |
1812 | &snd_ctl_f_ops, card, &card->ctl_dev); | |
1da177e4 LT |
1813 | } |
1814 | ||
1815 | /* | |
1816 | * disconnection of the control device | |
1817 | */ | |
82e9bae6 | 1818 | static int snd_ctl_dev_disconnect(struct snd_device *device) |
1da177e4 | 1819 | { |
82e9bae6 | 1820 | struct snd_card *card = device->device_data; |
82e9bae6 | 1821 | struct snd_ctl_file *ctl; |
1da177e4 | 1822 | |
d8009882 | 1823 | read_lock(&card->ctl_files_rwlock); |
9244b2c3 | 1824 | list_for_each_entry(ctl, &card->ctl_files, list) { |
1da177e4 LT |
1825 | wake_up(&ctl->change_sleep); |
1826 | kill_fasync(&ctl->fasync, SIGIO, POLL_ERR); | |
1827 | } | |
d8009882 | 1828 | read_unlock(&card->ctl_files_rwlock); |
c461482c | 1829 | |
40a4b263 | 1830 | return snd_unregister_device(&card->ctl_dev); |
1da177e4 LT |
1831 | } |
1832 | ||
1833 | /* | |
1834 | * free all controls | |
1835 | */ | |
82e9bae6 | 1836 | static int snd_ctl_dev_free(struct snd_device *device) |
1da177e4 | 1837 | { |
82e9bae6 TI |
1838 | struct snd_card *card = device->device_data; |
1839 | struct snd_kcontrol *control; | |
1da177e4 LT |
1840 | |
1841 | down_write(&card->controls_rwsem); | |
1842 | while (!list_empty(&card->controls)) { | |
1843 | control = snd_kcontrol(card->controls.next); | |
1844 | snd_ctl_remove(card, control); | |
1845 | } | |
1846 | up_write(&card->controls_rwsem); | |
0fcd9f4b | 1847 | put_device(&card->ctl_dev); |
1da177e4 LT |
1848 | return 0; |
1849 | } | |
1850 | ||
1da177e4 LT |
1851 | /* |
1852 | * create control core: | |
1853 | * called from init.c | |
1854 | */ | |
82e9bae6 | 1855 | int snd_ctl_create(struct snd_card *card) |
1da177e4 | 1856 | { |
82e9bae6 | 1857 | static struct snd_device_ops ops = { |
1da177e4 LT |
1858 | .dev_free = snd_ctl_dev_free, |
1859 | .dev_register = snd_ctl_dev_register, | |
1860 | .dev_disconnect = snd_ctl_dev_disconnect, | |
1da177e4 | 1861 | }; |
0fcd9f4b | 1862 | int err; |
1da177e4 | 1863 | |
7eaa943c TI |
1864 | if (snd_BUG_ON(!card)) |
1865 | return -ENXIO; | |
0fcd9f4b TI |
1866 | if (snd_BUG_ON(card->number < 0 || card->number >= SNDRV_CARDS)) |
1867 | return -ENXIO; | |
1868 | ||
1869 | snd_device_initialize(&card->ctl_dev, card); | |
1870 | dev_set_name(&card->ctl_dev, "controlC%d", card->number); | |
1871 | ||
1872 | err = snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops); | |
1873 | if (err < 0) | |
1874 | put_device(&card->ctl_dev); | |
1875 | return err; | |
1da177e4 | 1876 | } |
b9ed4f2b TI |
1877 | |
1878 | /* | |
9600732b | 1879 | * Frequently used control callbacks/helpers |
b9ed4f2b | 1880 | */ |
12cddbd8 TI |
1881 | |
1882 | /** | |
1883 | * snd_ctl_boolean_mono_info - Helper function for a standard boolean info | |
1884 | * callback with a mono channel | |
1885 | * @kcontrol: the kcontrol instance | |
1886 | * @uinfo: info to store | |
1887 | * | |
1888 | * This is a function that can be used as info callback for a standard | |
1889 | * boolean control with a single mono channel. | |
1890 | */ | |
b9ed4f2b TI |
1891 | int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol, |
1892 | struct snd_ctl_elem_info *uinfo) | |
1893 | { | |
1894 | uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN; | |
1895 | uinfo->count = 1; | |
1896 | uinfo->value.integer.min = 0; | |
1897 | uinfo->value.integer.max = 1; | |
1898 | return 0; | |
1899 | } | |
b9ed4f2b TI |
1900 | EXPORT_SYMBOL(snd_ctl_boolean_mono_info); |
1901 | ||
12cddbd8 TI |
1902 | /** |
1903 | * snd_ctl_boolean_stereo_info - Helper function for a standard boolean info | |
1904 | * callback with stereo two channels | |
1905 | * @kcontrol: the kcontrol instance | |
1906 | * @uinfo: info to store | |
1907 | * | |
1908 | * This is a function that can be used as info callback for a standard | |
1909 | * boolean control with stereo two channels. | |
1910 | */ | |
b9ed4f2b TI |
1911 | int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol, |
1912 | struct snd_ctl_elem_info *uinfo) | |
1913 | { | |
1914 | uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN; | |
1915 | uinfo->count = 2; | |
1916 | uinfo->value.integer.min = 0; | |
1917 | uinfo->value.integer.max = 1; | |
1918 | return 0; | |
1919 | } | |
b9ed4f2b | 1920 | EXPORT_SYMBOL(snd_ctl_boolean_stereo_info); |
9600732b CL |
1921 | |
1922 | /** | |
1923 | * snd_ctl_enum_info - fills the info structure for an enumerated control | |
1924 | * @info: the structure to be filled | |
1925 | * @channels: the number of the control's channels; often one | |
1926 | * @items: the number of control values; also the size of @names | |
1927 | * @names: an array containing the names of all control values | |
1928 | * | |
1929 | * Sets all required fields in @info to their appropriate values. | |
1930 | * If the control's accessibility is not the default (readable and writable), | |
1931 | * the caller has to fill @info->access. | |
eb7c06e8 YB |
1932 | * |
1933 | * Return: Zero. | |
9600732b CL |
1934 | */ |
1935 | int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels, | |
1936 | unsigned int items, const char *const names[]) | |
1937 | { | |
1938 | info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED; | |
1939 | info->count = channels; | |
1940 | info->value.enumerated.items = items; | |
a7e6fb99 TI |
1941 | if (!items) |
1942 | return 0; | |
9600732b CL |
1943 | if (info->value.enumerated.item >= items) |
1944 | info->value.enumerated.item = items - 1; | |
df803e13 TI |
1945 | WARN(strlen(names[info->value.enumerated.item]) >= sizeof(info->value.enumerated.name), |
1946 | "ALSA: too long item name '%s'\n", | |
1947 | names[info->value.enumerated.item]); | |
9600732b CL |
1948 | strlcpy(info->value.enumerated.name, |
1949 | names[info->value.enumerated.item], | |
1950 | sizeof(info->value.enumerated.name)); | |
1951 | return 0; | |
1952 | } | |
1953 | EXPORT_SYMBOL(snd_ctl_enum_info); |