1 /* mixer.c
2 **
3 ** Copyright 2011, The Android Open Source Project
4 **
5 ** Redistribution and use in source and binary forms, with or without
6 ** modification, are permitted provided that the following conditions are met:
7 ** * Redistributions of source code must retain the above copyright
8 ** notice, this list of conditions and the following disclaimer.
9 ** * Redistributions in binary form must reproduce the above copyright
10 ** notice, this list of conditions and the following disclaimer in the
11 ** documentation and/or other materials provided with the distribution.
12 ** * Neither the name of The Android Open Source Project nor the names of
13 ** its contributors may be used to endorse or promote products derived
14 ** from this software without specific prior written permission.
15 **
16 ** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND
17 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 ** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE
20 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 ** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
26 ** DAMAGE.
27 */
28
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <unistd.h>
33 #include <fcntl.h>
34 #include <errno.h>
35 #include <ctype.h>
36
37 #include <sys/ioctl.h>
38
39 #include <linux/ioctl.h>
40 #define __force
41 #define __bitwise
42 #define __user
43 #include <sound/asound.h>
44
45 #include <tinyalsa/asoundlib.h>
46
47 struct mixer_ctl {
48 struct mixer *mixer;
49 struct snd_ctl_elem_info *info;
50 char **ename;
51 };
52
53 struct mixer {
54 int fd;
55 struct snd_ctl_card_info card_info;
56 struct snd_ctl_elem_info *elem_info;
57 struct mixer_ctl *ctl;
58 unsigned int count;
59 };
60
mixer_close(struct mixer * mixer)61 void mixer_close(struct mixer *mixer)
62 {
63 unsigned int n,m;
64
65 if (!mixer)
66 return;
67
68 if (mixer->fd >= 0)
69 close(mixer->fd);
70
71 if (mixer->ctl) {
72 for (n = 0; n < mixer->count; n++) {
73 if (mixer->ctl[n].ename) {
74 unsigned int max = mixer->ctl[n].info->value.enumerated.items;
75 for (m = 0; m < max; m++)
76 free(mixer->ctl[n].ename[m]);
77 free(mixer->ctl[n].ename);
78 }
79 }
80 free(mixer->ctl);
81 }
82
83 if (mixer->elem_info)
84 free(mixer->elem_info);
85
86 free(mixer);
87
88 /* TODO: verify frees */
89 }
90
mixer_open(unsigned int card)91 struct mixer *mixer_open(unsigned int card)
92 {
93 struct snd_ctl_elem_list elist;
94 struct snd_ctl_elem_info tmp;
95 struct snd_ctl_elem_id *eid = NULL;
96 struct mixer *mixer = NULL;
97 unsigned int n, m;
98 int fd;
99 char fn[256];
100
101 snprintf(fn, sizeof(fn), "/dev/snd/controlC%u", card);
102 fd = open(fn, O_RDWR);
103 if (fd < 0)
104 return 0;
105
106 memset(&elist, 0, sizeof(elist));
107 if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0)
108 goto fail;
109
110 mixer = calloc(1, sizeof(*mixer));
111 if (!mixer)
112 goto fail;
113
114 mixer->ctl = calloc(elist.count, sizeof(struct mixer_ctl));
115 mixer->elem_info = calloc(elist.count, sizeof(struct snd_ctl_elem_info));
116 if (!mixer->ctl || !mixer->elem_info)
117 goto fail;
118
119 if (ioctl(fd, SNDRV_CTL_IOCTL_CARD_INFO, &mixer->card_info) < 0)
120 goto fail;
121
122 eid = calloc(elist.count, sizeof(struct snd_ctl_elem_id));
123 if (!eid)
124 goto fail;
125
126 mixer->count = elist.count;
127 mixer->fd = fd;
128 elist.space = mixer->count;
129 elist.pids = eid;
130 if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0)
131 goto fail;
132
133 for (n = 0; n < mixer->count; n++) {
134 struct snd_ctl_elem_info *ei = mixer->elem_info + n;
135 ei->id.numid = eid[n].numid;
136 if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, ei) < 0)
137 goto fail;
138 mixer->ctl[n].info = ei;
139 mixer->ctl[n].mixer = mixer;
140 if (ei->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) {
141 char **enames = calloc(ei->value.enumerated.items, sizeof(char*));
142 if (!enames)
143 goto fail;
144 mixer->ctl[n].ename = enames;
145 for (m = 0; m < ei->value.enumerated.items; m++) {
146 memset(&tmp, 0, sizeof(tmp));
147 tmp.id.numid = ei->id.numid;
148 tmp.value.enumerated.item = m;
149 if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, &tmp) < 0)
150 goto fail;
151 enames[m] = strdup(tmp.value.enumerated.name);
152 if (!enames[m])
153 goto fail;
154 }
155 }
156 }
157
158 free(eid);
159 return mixer;
160
161 fail:
162 /* TODO: verify frees in failure case */
163 if (eid)
164 free(eid);
165 if (mixer)
166 mixer_close(mixer);
167 else if (fd >= 0)
168 close(fd);
169 return 0;
170 }
171
mixer_get_name(struct mixer * mixer)172 const char *mixer_get_name(struct mixer *mixer)
173 {
174 return (const char *)mixer->card_info.name;
175 }
176
mixer_get_num_ctls(struct mixer * mixer)177 unsigned int mixer_get_num_ctls(struct mixer *mixer)
178 {
179 if (!mixer)
180 return 0;
181
182 return mixer->count;
183 }
184
mixer_get_ctl(struct mixer * mixer,unsigned int id)185 struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id)
186 {
187 if (mixer && (id < mixer->count))
188 return mixer->ctl + id;
189
190 return NULL;
191 }
192
mixer_get_ctl_by_name(struct mixer * mixer,const char * name)193 struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name)
194 {
195 unsigned int n;
196
197 if (!mixer)
198 return NULL;
199
200 for (n = 0; n < mixer->count; n++)
201 if (!strcmp(name, (char*) mixer->elem_info[n].id.name))
202 return mixer->ctl + n;
203
204 return NULL;
205 }
206
mixer_ctl_update(struct mixer_ctl * ctl)207 void mixer_ctl_update(struct mixer_ctl *ctl)
208 {
209 ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_INFO, ctl->info);
210 }
211
mixer_ctl_get_name(struct mixer_ctl * ctl)212 const char *mixer_ctl_get_name(struct mixer_ctl *ctl)
213 {
214 if (!ctl)
215 return NULL;
216
217 return (const char *)ctl->info->id.name;
218 }
219
mixer_ctl_get_type(struct mixer_ctl * ctl)220 enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl)
221 {
222 if (!ctl)
223 return MIXER_CTL_TYPE_UNKNOWN;
224
225 switch (ctl->info->type) {
226 case SNDRV_CTL_ELEM_TYPE_BOOLEAN: return MIXER_CTL_TYPE_BOOL;
227 case SNDRV_CTL_ELEM_TYPE_INTEGER: return MIXER_CTL_TYPE_INT;
228 case SNDRV_CTL_ELEM_TYPE_ENUMERATED: return MIXER_CTL_TYPE_ENUM;
229 case SNDRV_CTL_ELEM_TYPE_BYTES: return MIXER_CTL_TYPE_BYTE;
230 case SNDRV_CTL_ELEM_TYPE_IEC958: return MIXER_CTL_TYPE_IEC958;
231 case SNDRV_CTL_ELEM_TYPE_INTEGER64: return MIXER_CTL_TYPE_INT64;
232 default: return MIXER_CTL_TYPE_UNKNOWN;
233 };
234 }
235
mixer_ctl_get_type_string(struct mixer_ctl * ctl)236 const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl)
237 {
238 if (!ctl)
239 return "";
240
241 switch (ctl->info->type) {
242 case SNDRV_CTL_ELEM_TYPE_BOOLEAN: return "BOOL";
243 case SNDRV_CTL_ELEM_TYPE_INTEGER: return "INT";
244 case SNDRV_CTL_ELEM_TYPE_ENUMERATED: return "ENUM";
245 case SNDRV_CTL_ELEM_TYPE_BYTES: return "BYTE";
246 case SNDRV_CTL_ELEM_TYPE_IEC958: return "IEC958";
247 case SNDRV_CTL_ELEM_TYPE_INTEGER64: return "INT64";
248 default: return "Unknown";
249 };
250 }
251
mixer_ctl_get_num_values(struct mixer_ctl * ctl)252 unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl)
253 {
254 if (!ctl)
255 return 0;
256
257 return ctl->info->count;
258 }
259
percent_to_int(struct snd_ctl_elem_info * ei,int percent)260 static int percent_to_int(struct snd_ctl_elem_info *ei, int percent)
261 {
262 int range;
263
264 if (percent > 100)
265 percent = 100;
266 else if (percent < 0)
267 percent = 0;
268
269 range = (ei->value.integer.max - ei->value.integer.min);
270
271 return ei->value.integer.min + (range * percent) / 100;
272 }
273
int_to_percent(struct snd_ctl_elem_info * ei,int value)274 static int int_to_percent(struct snd_ctl_elem_info *ei, int value)
275 {
276 int range = (ei->value.integer.max - ei->value.integer.min);
277
278 if (range == 0)
279 return 0;
280
281 return ((value - ei->value.integer.min) / range) * 100;
282 }
283
mixer_ctl_get_percent(struct mixer_ctl * ctl,unsigned int id)284 int mixer_ctl_get_percent(struct mixer_ctl *ctl, unsigned int id)
285 {
286 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER))
287 return -EINVAL;
288
289 return int_to_percent(ctl->info, mixer_ctl_get_value(ctl, id));
290 }
291
mixer_ctl_set_percent(struct mixer_ctl * ctl,unsigned int id,int percent)292 int mixer_ctl_set_percent(struct mixer_ctl *ctl, unsigned int id, int percent)
293 {
294 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER))
295 return -EINVAL;
296
297 return mixer_ctl_set_value(ctl, id, percent_to_int(ctl->info, percent));
298 }
299
mixer_ctl_get_value(struct mixer_ctl * ctl,unsigned int id)300 int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id)
301 {
302 struct snd_ctl_elem_value ev;
303 int ret;
304
305 if (!ctl || (id >= ctl->info->count))
306 return -EINVAL;
307
308 memset(&ev, 0, sizeof(ev));
309 ev.id.numid = ctl->info->id.numid;
310 ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev);
311 if (ret < 0)
312 return ret;
313
314 switch (ctl->info->type) {
315 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
316 return !!ev.value.integer.value[id];
317
318 case SNDRV_CTL_ELEM_TYPE_INTEGER:
319 return ev.value.integer.value[id];
320
321 case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
322 return ev.value.enumerated.item[id];
323
324 case SNDRV_CTL_ELEM_TYPE_BYTES:
325 return ev.value.bytes.data[id];
326
327 default:
328 return -EINVAL;
329 }
330
331 return 0;
332 }
333
mixer_ctl_get_array(struct mixer_ctl * ctl,void * array,size_t count)334 int mixer_ctl_get_array(struct mixer_ctl *ctl, void *array, size_t count)
335 {
336 struct snd_ctl_elem_value ev;
337 int ret;
338 size_t size;
339 void *source;
340
341 if (!ctl || (count > ctl->info->count) || !count || !array)
342 return -EINVAL;
343
344 memset(&ev, 0, sizeof(ev));
345 ev.id.numid = ctl->info->id.numid;
346
347 ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev);
348 if (ret < 0)
349 return ret;
350
351 switch (ctl->info->type) {
352 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
353 case SNDRV_CTL_ELEM_TYPE_INTEGER:
354 size = sizeof(ev.value.integer.value[0]);
355 source = ev.value.integer.value;
356 break;
357
358 case SNDRV_CTL_ELEM_TYPE_BYTES:
359 size = sizeof(ev.value.bytes.data[0]);
360 source = ev.value.bytes.data;
361 break;
362
363 default:
364 return -EINVAL;
365 }
366
367 memcpy(array, source, size * count);
368
369 return 0;
370 }
371
mixer_ctl_set_value(struct mixer_ctl * ctl,unsigned int id,int value)372 int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value)
373 {
374 struct snd_ctl_elem_value ev;
375 int ret;
376
377 if (!ctl || (id >= ctl->info->count))
378 return -EINVAL;
379
380 memset(&ev, 0, sizeof(ev));
381 ev.id.numid = ctl->info->id.numid;
382 ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev);
383 if (ret < 0)
384 return ret;
385
386 switch (ctl->info->type) {
387 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
388 ev.value.integer.value[id] = !!value;
389 break;
390
391 case SNDRV_CTL_ELEM_TYPE_INTEGER:
392 ev.value.integer.value[id] = value;
393 break;
394
395 case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
396 ev.value.enumerated.item[id] = value;
397 break;
398
399 default:
400 return -EINVAL;
401 }
402
403 return ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev);
404 }
405
mixer_ctl_set_array(struct mixer_ctl * ctl,const void * array,size_t count)406 int mixer_ctl_set_array(struct mixer_ctl *ctl, const void *array, size_t count)
407 {
408 struct snd_ctl_elem_value ev;
409 size_t size;
410 void *dest;
411
412 if (!ctl || (count > ctl->info->count) || !count || !array)
413 return -EINVAL;
414
415 memset(&ev, 0, sizeof(ev));
416 ev.id.numid = ctl->info->id.numid;
417
418 switch (ctl->info->type) {
419 case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
420 case SNDRV_CTL_ELEM_TYPE_INTEGER:
421 size = sizeof(ev.value.integer.value[0]);
422 dest = ev.value.integer.value;
423 break;
424
425 case SNDRV_CTL_ELEM_TYPE_BYTES:
426 size = sizeof(ev.value.bytes.data[0]);
427 dest = ev.value.bytes.data;
428 break;
429
430 default:
431 return -EINVAL;
432 }
433
434 memcpy(dest, array, size * count);
435
436 return ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev);
437 }
438
mixer_ctl_get_range_min(struct mixer_ctl * ctl)439 int mixer_ctl_get_range_min(struct mixer_ctl *ctl)
440 {
441 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER))
442 return -EINVAL;
443
444 return ctl->info->value.integer.min;
445 }
446
mixer_ctl_get_range_max(struct mixer_ctl * ctl)447 int mixer_ctl_get_range_max(struct mixer_ctl *ctl)
448 {
449 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER))
450 return -EINVAL;
451
452 return ctl->info->value.integer.max;
453 }
454
mixer_ctl_get_num_enums(struct mixer_ctl * ctl)455 unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl)
456 {
457 if (!ctl)
458 return 0;
459
460 return ctl->info->value.enumerated.items;
461 }
462
mixer_ctl_get_enum_string(struct mixer_ctl * ctl,unsigned int enum_id)463 const char *mixer_ctl_get_enum_string(struct mixer_ctl *ctl,
464 unsigned int enum_id)
465 {
466 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_ENUMERATED) ||
467 (enum_id >= ctl->info->value.enumerated.items))
468 return NULL;
469
470 return (const char *)ctl->ename[enum_id];
471 }
472
mixer_ctl_set_enum_by_string(struct mixer_ctl * ctl,const char * string)473 int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string)
474 {
475 unsigned int i, num_enums;
476 struct snd_ctl_elem_value ev;
477 int ret;
478
479 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_ENUMERATED))
480 return -EINVAL;
481
482 num_enums = ctl->info->value.enumerated.items;
483 for (i = 0; i < num_enums; i++) {
484 if (!strcmp(string, ctl->ename[i])) {
485 memset(&ev, 0, sizeof(ev));
486 ev.value.enumerated.item[0] = i;
487 ev.id.numid = ctl->info->id.numid;
488 ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev);
489 if (ret < 0)
490 return ret;
491 return 0;
492 }
493 }
494
495 return -EINVAL;
496 }
497
498