blob: d0f11f37889b58e3ef771ba4605fc2e683c3ecca [file] [log] [blame]
Thomas Gleixnera10e7632019-05-31 01:09:32 -07001// SPDX-License-Identifier: GPL-2.0-only
Takashi Iwai3b0a5f22008-01-10 16:52:42 +01002/*
Takashi Iwai9ab0cb32020-07-17 17:45:17 +02003 * Virtual master and follower controls
Takashi Iwai3b0a5f22008-01-10 16:52:42 +01004 *
5 * Copyright (c) 2008 by Takashi Iwai <tiwai@suse.de>
Takashi Iwai3b0a5f22008-01-10 16:52:42 +01006 */
7
8#include <linux/slab.h>
Paul Gortmakerd81a6d72011-09-22 09:34:58 -04009#include <linux/export.h>
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010010#include <sound/core.h>
11#include <sound/control.h>
Takashi Iwai1c82ed1b2008-02-18 13:05:50 +010012#include <sound/tlv.h>
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010013
14/*
15 * a subset of information returned via ctl info callback
16 */
17struct link_ctl_info {
Clemens Ladischfea952e2011-02-14 11:00:47 +010018 snd_ctl_elem_type_t type; /* value type */
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010019 int count; /* item count */
20 int min_val, max_val; /* min, max values */
21};
22
23/*
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020024 * link master - this contains a list of follower controls that are
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010025 * identical types, i.e. info returns the same value type and value
26 * ranges, but may have different number of counts.
27 *
28 * The master control is so far only mono volume/switch for simplicity.
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020029 * The same value will be applied to all followers.
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010030 */
31struct link_master {
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020032 struct list_head followers;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010033 struct link_ctl_info info;
34 int val; /* the master value */
Takashi Iwai1c82ed1b2008-02-18 13:05:50 +010035 unsigned int tlv[4];
Takashi Iwai2ad787e2012-03-12 12:18:37 +010036 void (*hook)(void *private_data, int);
37 void *hook_private_data;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010038};
39
40/*
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020041 * link follower - this contains a follower control element
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010042 *
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020043 * It fakes the control callbacks with additional attenuation by the
44 * master control. A follower may have either one or two channels.
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010045 */
46
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020047struct link_follower {
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010048 struct list_head list;
49 struct link_master *master;
50 struct link_ctl_info info;
51 int vals[2]; /* current values */
Takashi Iwaif5b1db62009-01-16 18:15:22 +010052 unsigned int flags;
Takashi Iwai9e226b42011-11-10 12:34:24 +010053 struct snd_kcontrol *kctl; /* original kcontrol pointer */
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020054 struct snd_kcontrol follower; /* the copy of original control entry */
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010055};
56
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020057static int follower_update(struct link_follower *follower)
Takashi Iwaif5b1db62009-01-16 18:15:22 +010058{
59 struct snd_ctl_elem_value *uctl;
60 int err, ch;
61
Takashi Iwai7a33a022018-03-08 08:32:41 +010062 uctl = kzalloc(sizeof(*uctl), GFP_KERNEL);
Takashi Iwaif5b1db62009-01-16 18:15:22 +010063 if (!uctl)
64 return -ENOMEM;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020065 uctl->id = follower->follower.id;
66 err = follower->follower.get(&follower->follower, uctl);
Takashi Iwai2e2c1772018-03-08 08:26:48 +010067 if (err < 0)
68 goto error;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020069 for (ch = 0; ch < follower->info.count; ch++)
70 follower->vals[ch] = uctl->value.integer.value[ch];
Takashi Iwai2e2c1772018-03-08 08:26:48 +010071 error:
Takashi Iwaif5b1db62009-01-16 18:15:22 +010072 kfree(uctl);
Takashi Iwai2e2c1772018-03-08 08:26:48 +010073 return err < 0 ? err : 0;
Takashi Iwaif5b1db62009-01-16 18:15:22 +010074}
75
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020076/* get the follower ctl info and save the initial values */
77static int follower_init(struct link_follower *follower)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010078{
79 struct snd_ctl_elem_info *uinfo;
Takashi Iwaif5b1db62009-01-16 18:15:22 +010080 int err;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010081
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020082 if (follower->info.count) {
Takashi Iwaif5b1db62009-01-16 18:15:22 +010083 /* already initialized */
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020084 if (follower->flags & SND_CTL_FOLLOWER_NEED_UPDATE)
85 return follower_update(follower);
Takashi Iwaif5b1db62009-01-16 18:15:22 +010086 return 0;
87 }
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010088
89 uinfo = kmalloc(sizeof(*uinfo), GFP_KERNEL);
90 if (!uinfo)
91 return -ENOMEM;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020092 uinfo->id = follower->follower.id;
93 err = follower->follower.info(&follower->follower, uinfo);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +010094 if (err < 0) {
95 kfree(uinfo);
96 return err;
97 }
Takashi Iwai9ab0cb32020-07-17 17:45:17 +020098 follower->info.type = uinfo->type;
99 follower->info.count = uinfo->count;
100 if (follower->info.count > 2 ||
101 (follower->info.type != SNDRV_CTL_ELEM_TYPE_INTEGER &&
102 follower->info.type != SNDRV_CTL_ELEM_TYPE_BOOLEAN)) {
103 pr_err("ALSA: vmaster: invalid follower element\n");
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100104 kfree(uinfo);
105 return -EINVAL;
106 }
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200107 follower->info.min_val = uinfo->value.integer.min;
108 follower->info.max_val = uinfo->value.integer.max;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100109 kfree(uinfo);
110
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200111 return follower_update(follower);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100112}
113
114/* initialize master volume */
115static int master_init(struct link_master *master)
116{
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200117 struct link_follower *follower;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100118
119 if (master->info.count)
120 return 0; /* already initialized */
121
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200122 list_for_each_entry(follower, &master->followers, list) {
123 int err = follower_init(follower);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100124 if (err < 0)
125 return err;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200126 master->info = follower->info;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100127 master->info.count = 1; /* always mono */
128 /* set full volume as default (= no attenuation) */
129 master->val = master->info.max_val;
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100130 if (master->hook)
131 master->hook(master->hook_private_data, master->val);
132 return 1;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100133 }
134 return -ENOENT;
135}
136
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200137static int follower_get_val(struct link_follower *follower,
138 struct snd_ctl_elem_value *ucontrol)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100139{
140 int err, ch;
141
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200142 err = follower_init(follower);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100143 if (err < 0)
144 return err;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200145 for (ch = 0; ch < follower->info.count; ch++)
146 ucontrol->value.integer.value[ch] = follower->vals[ch];
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100147 return 0;
148}
149
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200150static int follower_put_val(struct link_follower *follower,
151 struct snd_ctl_elem_value *ucontrol)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100152{
153 int err, ch, vol;
154
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200155 err = master_init(follower->master);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100156 if (err < 0)
157 return err;
158
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200159 switch (follower->info.type) {
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100160 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200161 for (ch = 0; ch < follower->info.count; ch++)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100162 ucontrol->value.integer.value[ch] &=
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200163 !!follower->master->val;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100164 break;
165 case SNDRV_CTL_ELEM_TYPE_INTEGER:
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200166 for (ch = 0; ch < follower->info.count; ch++) {
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100167 /* max master volume is supposed to be 0 dB */
168 vol = ucontrol->value.integer.value[ch];
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200169 vol += follower->master->val - follower->master->info.max_val;
170 if (vol < follower->info.min_val)
171 vol = follower->info.min_val;
172 else if (vol > follower->info.max_val)
173 vol = follower->info.max_val;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100174 ucontrol->value.integer.value[ch] = vol;
175 }
176 break;
177 }
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200178 return follower->follower.put(&follower->follower, ucontrol);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100179}
180
181/*
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200182 * ctl callbacks for followers
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100183 */
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200184static int follower_info(struct snd_kcontrol *kcontrol,
185 struct snd_ctl_elem_info *uinfo)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100186{
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200187 struct link_follower *follower = snd_kcontrol_chip(kcontrol);
188 return follower->follower.info(&follower->follower, uinfo);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100189}
190
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200191static int follower_get(struct snd_kcontrol *kcontrol,
192 struct snd_ctl_elem_value *ucontrol)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100193{
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200194 struct link_follower *follower = snd_kcontrol_chip(kcontrol);
195 return follower_get_val(follower, ucontrol);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100196}
197
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200198static int follower_put(struct snd_kcontrol *kcontrol,
199 struct snd_ctl_elem_value *ucontrol)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100200{
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200201 struct link_follower *follower = snd_kcontrol_chip(kcontrol);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100202 int err, ch, changed = 0;
203
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200204 err = follower_init(follower);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100205 if (err < 0)
206 return err;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200207 for (ch = 0; ch < follower->info.count; ch++) {
208 if (follower->vals[ch] != ucontrol->value.integer.value[ch]) {
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100209 changed = 1;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200210 follower->vals[ch] = ucontrol->value.integer.value[ch];
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100211 }
212 }
213 if (!changed)
214 return 0;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200215 err = follower_put_val(follower, ucontrol);
Takashi Iwai2069d482013-03-05 15:43:39 +0100216 if (err < 0)
217 return err;
218 return 1;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100219}
220
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200221static int follower_tlv_cmd(struct snd_kcontrol *kcontrol,
222 int op_flag, unsigned int size,
223 unsigned int __user *tlv)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100224{
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200225 struct link_follower *follower = snd_kcontrol_chip(kcontrol);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100226 /* FIXME: this assumes that the max volume is 0 dB */
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200227 return follower->follower.tlv.c(&follower->follower, op_flag, size, tlv);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100228}
229
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200230static void follower_free(struct snd_kcontrol *kcontrol)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100231{
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200232 struct link_follower *follower = snd_kcontrol_chip(kcontrol);
233 if (follower->follower.private_free)
234 follower->follower.private_free(&follower->follower);
235 if (follower->master)
236 list_del(&follower->list);
237 kfree(follower);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100238}
239
240/*
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200241 * Add a follower control to the group with the given master control
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100242 *
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200243 * All followers must be the same type (returning the same information
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300244 * via info callback). The function doesn't check it, so it's your
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100245 * responsibility.
246 *
247 * Also, some additional limitations:
248 * - at most two channels
249 * - logarithmic volume control (dB level), no linear volume
250 * - master can only attenuate the volume, no gain
251 */
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200252int _snd_ctl_add_follower(struct snd_kcontrol *master,
253 struct snd_kcontrol *follower,
254 unsigned int flags)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100255{
256 struct link_master *master_link = snd_kcontrol_chip(master);
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200257 struct link_follower *srec;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100258
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200259 srec = kzalloc(struct_size(srec, follower.vd, follower->count),
Kees Cookacafe7e2018-05-08 13:45:50 -0700260 GFP_KERNEL);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100261 if (!srec)
262 return -ENOMEM;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200263 srec->kctl = follower;
264 srec->follower = *follower;
265 memcpy(srec->follower.vd, follower->vd, follower->count * sizeof(*follower->vd));
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100266 srec->master = master_link;
Takashi Iwaif5b1db62009-01-16 18:15:22 +0100267 srec->flags = flags;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100268
269 /* override callbacks */
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200270 follower->info = follower_info;
271 follower->get = follower_get;
272 follower->put = follower_put;
273 if (follower->vd[0].access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK)
274 follower->tlv.c = follower_tlv_cmd;
275 follower->private_data = srec;
276 follower->private_free = follower_free;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100277
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200278 list_add_tail(&srec->list, &master_link->followers);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100279 return 0;
280}
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200281EXPORT_SYMBOL(_snd_ctl_add_follower);
Takashi Iwaie922b002008-02-18 13:03:13 +0100282
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100283/*
284 * ctl callbacks for master controls
285 */
286static int master_info(struct snd_kcontrol *kcontrol,
287 struct snd_ctl_elem_info *uinfo)
288{
289 struct link_master *master = snd_kcontrol_chip(kcontrol);
290 int ret;
291
292 ret = master_init(master);
293 if (ret < 0)
294 return ret;
295 uinfo->type = master->info.type;
296 uinfo->count = master->info.count;
297 uinfo->value.integer.min = master->info.min_val;
298 uinfo->value.integer.max = master->info.max_val;
299 return 0;
300}
301
302static int master_get(struct snd_kcontrol *kcontrol,
303 struct snd_ctl_elem_value *ucontrol)
304{
305 struct link_master *master = snd_kcontrol_chip(kcontrol);
306 int err = master_init(master);
307 if (err < 0)
308 return err;
309 ucontrol->value.integer.value[0] = master->val;
310 return 0;
311}
312
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200313static int sync_followers(struct link_master *master, int old_val, int new_val)
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100314{
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200315 struct link_follower *follower;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100316 struct snd_ctl_elem_value *uval;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100317
318 uval = kmalloc(sizeof(*uval), GFP_KERNEL);
319 if (!uval)
320 return -ENOMEM;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200321 list_for_each_entry(follower, &master->followers, list) {
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100322 master->val = old_val;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200323 uval->id = follower->follower.id;
324 follower_get_val(follower, uval);
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200325 master->val = new_val;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200326 follower_put_val(follower, uval);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100327 }
328 kfree(uval);
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200329 return 0;
330}
331
332static int master_put(struct snd_kcontrol *kcontrol,
333 struct snd_ctl_elem_value *ucontrol)
334{
335 struct link_master *master = snd_kcontrol_chip(kcontrol);
336 int err, new_val, old_val;
337 bool first_init;
338
339 err = master_init(master);
340 if (err < 0)
341 return err;
342 first_init = err;
343 old_val = master->val;
344 new_val = ucontrol->value.integer.value[0];
345 if (new_val == old_val)
346 return 0;
347
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200348 err = sync_followers(master, old_val, new_val);
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200349 if (err < 0)
350 return err;
Takashi Iwai1ba65ae2013-07-03 14:01:32 +0200351 if (master->hook && !first_init)
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100352 master->hook(master->hook_private_data, master->val);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100353 return 1;
354}
355
356static void master_free(struct snd_kcontrol *kcontrol)
357{
358 struct link_master *master = snd_kcontrol_chip(kcontrol);
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200359 struct link_follower *follower, *n;
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100360
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200361 /* free all follower links and retore the original follower kctls */
362 list_for_each_entry_safe(follower, n, &master->followers, list) {
363 struct snd_kcontrol *sctl = follower->kctl;
Takashi Iwai9e226b42011-11-10 12:34:24 +0100364 struct list_head olist = sctl->list;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200365 memcpy(sctl, &follower->follower, sizeof(*sctl));
366 memcpy(sctl->vd, follower->follower.vd,
Takashi Iwai9e226b42011-11-10 12:34:24 +0100367 sctl->count * sizeof(*sctl->vd));
368 sctl->list = olist; /* keep the current linked-list */
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200369 kfree(follower);
Takashi Iwai9e226b42011-11-10 12:34:24 +0100370 }
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100371 kfree(master);
372}
373
374
Takashi Iwai79c7cdd2009-02-09 14:47:19 +0100375/**
376 * snd_ctl_make_virtual_master - Create a virtual master control
377 * @name: name string of the control element to create
378 * @tlv: optional TLV int array for dB information
379 *
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100380 * Creates a virtual master control with the given name string.
Takashi Iwai79c7cdd2009-02-09 14:47:19 +0100381 *
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200382 * After creating a vmaster element, you can add the follower controls
383 * via snd_ctl_add_follower() or snd_ctl_add_follower_uncached().
Takashi Iwai79c7cdd2009-02-09 14:47:19 +0100384 *
385 * The optional argument @tlv can be used to specify the TLV information
386 * for dB scale of the master control. It should be a single element
Takashi Iwai085f3062009-06-16 13:57:07 +0200387 * with #SNDRV_CTL_TLVT_DB_SCALE, #SNDRV_CTL_TLV_DB_MINMAX or
388 * #SNDRV_CTL_TLVT_DB_MINMAX_MUTE type, and should be the max 0dB.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100389 *
390 * Return: The created control element, or %NULL for errors (ENOMEM).
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100391 */
392struct snd_kcontrol *snd_ctl_make_virtual_master(char *name,
393 const unsigned int *tlv)
394{
395 struct link_master *master;
396 struct snd_kcontrol *kctl;
397 struct snd_kcontrol_new knew;
398
399 memset(&knew, 0, sizeof(knew));
400 knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
401 knew.name = name;
402 knew.info = master_info;
403
404 master = kzalloc(sizeof(*master), GFP_KERNEL);
405 if (!master)
406 return NULL;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200407 INIT_LIST_HEAD(&master->followers);
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100408
409 kctl = snd_ctl_new1(&knew, master);
410 if (!kctl) {
411 kfree(master);
412 return NULL;
413 }
414 /* override some callbacks */
415 kctl->info = master_info;
416 kctl->get = master_get;
417 kctl->put = master_put;
418 kctl->private_free = master_free;
419
420 /* additional (constant) TLV read */
Takashi Sakamoto841bdb72018-05-14 07:09:51 +0900421 if (tlv) {
422 unsigned int type = tlv[SNDRV_CTL_TLVO_TYPE];
423 if (type == SNDRV_CTL_TLVT_DB_SCALE ||
424 type == SNDRV_CTL_TLVT_DB_MINMAX ||
425 type == SNDRV_CTL_TLVT_DB_MINMAX_MUTE) {
426 kctl->vd[0].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
427 memcpy(master->tlv, tlv, sizeof(master->tlv));
428 kctl->tlv.p = master->tlv;
429 }
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100430 }
Takashi Iwai1c82ed1b2008-02-18 13:05:50 +0100431
Takashi Iwai3b0a5f22008-01-10 16:52:42 +0100432 return kctl;
433}
Takashi Iwaie922b002008-02-18 13:03:13 +0100434EXPORT_SYMBOL(snd_ctl_make_virtual_master);
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100435
436/**
437 * snd_ctl_add_vmaster_hook - Add a hook to a vmaster control
438 * @kcontrol: vmaster kctl element
439 * @hook: the hook function
Randy Dunlapf2ec52d2012-04-17 17:03:42 -0700440 * @private_data: the private_data pointer to be saved
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100441 *
442 * Adds the given hook to the vmaster control element so that it's called
443 * at each time when the value is changed.
Yacine Belkadieb7c06e2013-03-11 22:05:14 +0100444 *
445 * Return: Zero.
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100446 */
447int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kcontrol,
448 void (*hook)(void *private_data, int),
449 void *private_data)
450{
451 struct link_master *master = snd_kcontrol_chip(kcontrol);
452 master->hook = hook;
453 master->hook_private_data = private_data;
454 return 0;
455}
456EXPORT_SYMBOL_GPL(snd_ctl_add_vmaster_hook);
457
458/**
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200459 * snd_ctl_sync_vmaster - Sync the vmaster followers and hook
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100460 * @kcontrol: vmaster kctl element
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200461 * @hook_only: sync only the hook
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100462 *
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200463 * Forcibly call the put callback of each follower and call the hook function
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200464 * to synchronize with the current value of the given vmaster element.
465 * NOP when NULL is passed to @kcontrol.
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100466 */
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200467void snd_ctl_sync_vmaster(struct snd_kcontrol *kcontrol, bool hook_only)
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100468{
469 struct link_master *master;
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200470 bool first_init = false;
471
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100472 if (!kcontrol)
473 return;
474 master = snd_kcontrol_chip(kcontrol);
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200475 if (!hook_only) {
476 int err = master_init(master);
477 if (err < 0)
478 return;
479 first_init = err;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200480 err = sync_followers(master, master->val, master->val);
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200481 if (err < 0)
482 return;
483 }
484
485 if (master->hook && !first_init)
Takashi Iwai2ad787e2012-03-12 12:18:37 +0100486 master->hook(master->hook_private_data, master->val);
487}
Takashi Iwai1ca2f2e2013-06-24 15:51:54 +0200488EXPORT_SYMBOL_GPL(snd_ctl_sync_vmaster);
Takashi Iwaia91d6612017-10-16 11:39:28 +0200489
490/**
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200491 * snd_ctl_apply_vmaster_followers - Apply function to each vmaster follower
Takashi Iwaia91d6612017-10-16 11:39:28 +0200492 * @kctl: vmaster kctl element
493 * @func: function to apply
494 * @arg: optional function argument
495 *
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200496 * Apply the function @func to each follower kctl of the given vmaster kctl.
Takashi Iwai281dee62022-07-13 12:47:59 +0200497 *
498 * Return: 0 if successful, or a negative error code
Takashi Iwaia91d6612017-10-16 11:39:28 +0200499 */
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200500int snd_ctl_apply_vmaster_followers(struct snd_kcontrol *kctl,
501 int (*func)(struct snd_kcontrol *vfollower,
502 struct snd_kcontrol *follower,
503 void *arg),
504 void *arg)
Takashi Iwaia91d6612017-10-16 11:39:28 +0200505{
506 struct link_master *master;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200507 struct link_follower *follower;
Takashi Iwaia91d6612017-10-16 11:39:28 +0200508 int err;
509
510 master = snd_kcontrol_chip(kctl);
511 err = master_init(master);
512 if (err < 0)
513 return err;
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200514 list_for_each_entry(follower, &master->followers, list) {
515 err = func(follower->kctl, &follower->follower, arg);
Takashi Iwaia91d6612017-10-16 11:39:28 +0200516 if (err < 0)
517 return err;
518 }
519
520 return 0;
521}
Takashi Iwai9ab0cb32020-07-17 17:45:17 +0200522EXPORT_SYMBOL_GPL(snd_ctl_apply_vmaster_followers);