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 <stdint.h>
32 #include <string.h>
33 #include <unistd.h>
34 #include <fcntl.h>
35 #include <errno.h>
36 #include <ctype.h>
37 
38 #include <sys/ioctl.h>
39 
40 #include <linux/ioctl.h>
41 #define __force
42 #define __bitwise
43 #define __user
44 #include <sound/asound.h>
45 
46 #include <tinyalsa/asoundlib.h>
47 
48 struct mixer_ctl {
49     struct mixer *mixer;
50     struct snd_ctl_elem_info *info;
51     char **ename;
52 };
53 
54 struct mixer {
55     int fd;
56     struct snd_ctl_card_info card_info;
57     struct snd_ctl_elem_info *elem_info;
58     struct mixer_ctl *ctl;
59     unsigned int count;
60 };
61 
mixer_close(struct mixer * mixer)62 void mixer_close(struct mixer *mixer)
63 {
64     unsigned int n,m;
65 
66     if (!mixer)
67         return;
68 
69     if (mixer->fd >= 0)
70         close(mixer->fd);
71 
72     if (mixer->ctl) {
73         for (n = 0; n < mixer->count; n++) {
74             if (mixer->ctl[n].ename) {
75                 unsigned int max = mixer->ctl[n].info->value.enumerated.items;
76                 for (m = 0; m < max; m++)
77                     free(mixer->ctl[n].ename[m]);
78                 free(mixer->ctl[n].ename);
79             }
80         }
81         free(mixer->ctl);
82     }
83 
84     if (mixer->elem_info)
85         free(mixer->elem_info);
86 
87     free(mixer);
88 
89     /* TODO: verify frees */
90 }
91 
mixer_open(unsigned int card)92 struct mixer *mixer_open(unsigned int card)
93 {
94     struct snd_ctl_elem_list elist;
95     struct snd_ctl_elem_info tmp;
96     struct snd_ctl_elem_id *eid = NULL;
97     struct mixer *mixer = NULL;
98     unsigned int n, m;
99     int fd;
100     char fn[256];
101 
102     snprintf(fn, sizeof(fn), "/dev/snd/controlC%u", card);
103     fd = open(fn, O_RDWR);
104     if (fd < 0)
105         return 0;
106 
107     memset(&elist, 0, sizeof(elist));
108     if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0)
109         goto fail;
110 
111     mixer = calloc(1, sizeof(*mixer));
112     if (!mixer)
113         goto fail;
114 
115     mixer->ctl = calloc(elist.count, sizeof(struct mixer_ctl));
116     mixer->elem_info = calloc(elist.count, sizeof(struct snd_ctl_elem_info));
117     if (!mixer->ctl || !mixer->elem_info)
118         goto fail;
119 
120     if (ioctl(fd, SNDRV_CTL_IOCTL_CARD_INFO, &mixer->card_info) < 0)
121         goto fail;
122 
123     eid = calloc(elist.count, sizeof(struct snd_ctl_elem_id));
124     if (!eid)
125         goto fail;
126 
127     mixer->count = elist.count;
128     mixer->fd = fd;
129     elist.space = mixer->count;
130     elist.pids = eid;
131     if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0)
132         goto fail;
133 
134     for (n = 0; n < mixer->count; n++) {
135         struct snd_ctl_elem_info *ei = mixer->elem_info + n;
136         ei->id.numid = eid[n].numid;
137         if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, ei) < 0)
138             goto fail;
139         mixer->ctl[n].info = ei;
140         mixer->ctl[n].mixer = mixer;
141         if (ei->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) {
142             char **enames = calloc(ei->value.enumerated.items, sizeof(char*));
143             if (!enames)
144                 goto fail;
145             mixer->ctl[n].ename = enames;
146             for (m = 0; m < ei->value.enumerated.items; m++) {
147                 memset(&tmp, 0, sizeof(tmp));
148                 tmp.id.numid = ei->id.numid;
149                 tmp.value.enumerated.item = m;
150                 if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, &tmp) < 0)
151                     goto fail;
152                 enames[m] = strdup(tmp.value.enumerated.name);
153                 if (!enames[m])
154                     goto fail;
155             }
156         }
157     }
158 
159     free(eid);
160     return mixer;
161 
162 fail:
163     /* TODO: verify frees in failure case */
164     if (eid)
165         free(eid);
166     if (mixer)
167         mixer_close(mixer);
168     else if (fd >= 0)
169         close(fd);
170     return 0;
171 }
172 
mixer_get_name(struct mixer * mixer)173 const char *mixer_get_name(struct mixer *mixer)
174 {
175     return (const char *)mixer->card_info.name;
176 }
177 
mixer_get_num_ctls(struct mixer * mixer)178 unsigned int mixer_get_num_ctls(struct mixer *mixer)
179 {
180     if (!mixer)
181         return 0;
182 
183     return mixer->count;
184 }
185 
mixer_get_ctl(struct mixer * mixer,unsigned int id)186 struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id)
187 {
188     if (mixer && (id < mixer->count))
189         return mixer->ctl + id;
190 
191     return NULL;
192 }
193 
mixer_get_ctl_by_name(struct mixer * mixer,const char * name)194 struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name)
195 {
196     unsigned int n;
197 
198     if (!mixer)
199         return NULL;
200 
201     for (n = 0; n < mixer->count; n++)
202         if (!strcmp(name, (char*) mixer->elem_info[n].id.name))
203             return mixer->ctl + n;
204 
205     return NULL;
206 }
207 
mixer_ctl_update(struct mixer_ctl * ctl)208 void mixer_ctl_update(struct mixer_ctl *ctl)
209 {
210     ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_INFO, ctl->info);
211 }
212 
mixer_ctl_get_name(struct mixer_ctl * ctl)213 const char *mixer_ctl_get_name(struct mixer_ctl *ctl)
214 {
215     if (!ctl)
216         return NULL;
217 
218     return (const char *)ctl->info->id.name;
219 }
220 
mixer_ctl_get_type(struct mixer_ctl * ctl)221 enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl)
222 {
223     if (!ctl)
224         return MIXER_CTL_TYPE_UNKNOWN;
225 
226     switch (ctl->info->type) {
227     case SNDRV_CTL_ELEM_TYPE_BOOLEAN:    return MIXER_CTL_TYPE_BOOL;
228     case SNDRV_CTL_ELEM_TYPE_INTEGER:    return MIXER_CTL_TYPE_INT;
229     case SNDRV_CTL_ELEM_TYPE_ENUMERATED: return MIXER_CTL_TYPE_ENUM;
230     case SNDRV_CTL_ELEM_TYPE_BYTES:      return MIXER_CTL_TYPE_BYTE;
231     case SNDRV_CTL_ELEM_TYPE_IEC958:     return MIXER_CTL_TYPE_IEC958;
232     case SNDRV_CTL_ELEM_TYPE_INTEGER64:  return MIXER_CTL_TYPE_INT64;
233     default:                             return MIXER_CTL_TYPE_UNKNOWN;
234     };
235 }
236 
mixer_ctl_get_type_string(struct mixer_ctl * ctl)237 const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl)
238 {
239     if (!ctl)
240         return "";
241 
242     switch (ctl->info->type) {
243     case SNDRV_CTL_ELEM_TYPE_BOOLEAN:    return "BOOL";
244     case SNDRV_CTL_ELEM_TYPE_INTEGER:    return "INT";
245     case SNDRV_CTL_ELEM_TYPE_ENUMERATED: return "ENUM";
246     case SNDRV_CTL_ELEM_TYPE_BYTES:      return "BYTE";
247     case SNDRV_CTL_ELEM_TYPE_IEC958:     return "IEC958";
248     case SNDRV_CTL_ELEM_TYPE_INTEGER64:  return "INT64";
249     default:                             return "Unknown";
250     };
251 }
252 
mixer_ctl_get_num_values(struct mixer_ctl * ctl)253 unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl)
254 {
255     if (!ctl)
256         return 0;
257 
258     return ctl->info->count;
259 }
260 
percent_to_int(struct snd_ctl_elem_info * ei,int percent)261 static int percent_to_int(struct snd_ctl_elem_info *ei, int percent)
262 {
263     int range;
264 
265     if (percent > 100)
266         percent = 100;
267     else if (percent < 0)
268         percent = 0;
269 
270     range = (ei->value.integer.max - ei->value.integer.min);
271 
272     return ei->value.integer.min + (range * percent) / 100;
273 }
274 
int_to_percent(struct snd_ctl_elem_info * ei,int value)275 static int int_to_percent(struct snd_ctl_elem_info *ei, int value)
276 {
277     int range = (ei->value.integer.max - ei->value.integer.min);
278 
279     if (range == 0)
280         return 0;
281 
282     return ((value - ei->value.integer.min) / range) * 100;
283 }
284 
mixer_ctl_get_percent(struct mixer_ctl * ctl,unsigned int id)285 int mixer_ctl_get_percent(struct mixer_ctl *ctl, unsigned int id)
286 {
287     if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER))
288         return -EINVAL;
289 
290     return int_to_percent(ctl->info, mixer_ctl_get_value(ctl, id));
291 }
292 
mixer_ctl_set_percent(struct mixer_ctl * ctl,unsigned int id,int percent)293 int mixer_ctl_set_percent(struct mixer_ctl *ctl, unsigned int id, int percent)
294 {
295     if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER))
296         return -EINVAL;
297 
298     return mixer_ctl_set_value(ctl, id, percent_to_int(ctl->info, percent));
299 }
300 
mixer_ctl_get_value(struct mixer_ctl * ctl,unsigned int id)301 int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id)
302 {
303     struct snd_ctl_elem_value ev;
304     int ret;
305 
306     if (!ctl || (id >= ctl->info->count))
307         return -EINVAL;
308 
309     memset(&ev, 0, sizeof(ev));
310     ev.id.numid = ctl->info->id.numid;
311     ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev);
312     if (ret < 0)
313         return ret;
314 
315     switch (ctl->info->type) {
316     case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
317         return !!ev.value.integer.value[id];
318 
319     case SNDRV_CTL_ELEM_TYPE_INTEGER:
320         return ev.value.integer.value[id];
321 
322     case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
323         return ev.value.enumerated.item[id];
324 
325     case SNDRV_CTL_ELEM_TYPE_BYTES:
326         return ev.value.bytes.data[id];
327 
328     default:
329         return -EINVAL;
330     }
331 
332     return 0;
333 }
334 
mixer_ctl_get_array(struct mixer_ctl * ctl,void * array,size_t count)335 int mixer_ctl_get_array(struct mixer_ctl *ctl, void *array, size_t count)
336 {
337     struct snd_ctl_elem_value ev;
338     int ret = 0;
339     size_t size;
340     void *source;
341 
342     if (!ctl || (count > ctl->info->count) || !count || !array)
343         return -EINVAL;
344 
345     memset(&ev, 0, sizeof(ev));
346     ev.id.numid = ctl->info->id.numid;
347 
348     switch (ctl->info->type) {
349     case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
350     case SNDRV_CTL_ELEM_TYPE_INTEGER:
351         ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev);
352         if (ret < 0)
353             return ret;
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         /* check if this is new bytes TLV */
360         if (ctl->info->access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
361             struct snd_ctl_tlv *tlv;
362             int ret;
363 
364             if (count > SIZE_MAX - sizeof(*tlv))
365                 return -EINVAL;
366             tlv = calloc(1, sizeof(*tlv) + count);
367             if (!tlv)
368                 return -ENOMEM;
369             tlv->numid = ctl->info->id.numid;
370             tlv->length = count;
371             ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_TLV_READ, tlv);
372 
373             source = tlv->tlv;
374             memcpy(array, source, count);
375 
376             free(tlv);
377 
378             return ret;
379         } else {
380             ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev);
381             if (ret < 0)
382                 return ret;
383             size = sizeof(ev.value.bytes.data[0]);
384             source = ev.value.bytes.data;
385             break;
386         }
387 
388     case SNDRV_CTL_ELEM_TYPE_IEC958:
389         size = sizeof(ev.value.iec958);
390         source = &ev.value.iec958;
391         break;
392 
393     default:
394         return -EINVAL;
395     }
396 
397     memcpy(array, source, size * count);
398 
399     return 0;
400 }
401 
mixer_ctl_set_value(struct mixer_ctl * ctl,unsigned int id,int value)402 int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value)
403 {
404     struct snd_ctl_elem_value ev;
405     int ret;
406 
407     if (!ctl || (id >= ctl->info->count))
408         return -EINVAL;
409 
410     memset(&ev, 0, sizeof(ev));
411     ev.id.numid = ctl->info->id.numid;
412     ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev);
413     if (ret < 0)
414         return ret;
415 
416     switch (ctl->info->type) {
417     case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
418         ev.value.integer.value[id] = !!value;
419         break;
420 
421     case SNDRV_CTL_ELEM_TYPE_INTEGER:
422         ev.value.integer.value[id] = value;
423         break;
424 
425     case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
426         ev.value.enumerated.item[id] = value;
427         break;
428 
429     case SNDRV_CTL_ELEM_TYPE_BYTES:
430         ev.value.bytes.data[id] = value;
431         break;
432 
433     default:
434         return -EINVAL;
435     }
436 
437     return ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev);
438 }
439 
mixer_ctl_set_array(struct mixer_ctl * ctl,const void * array,size_t count)440 int mixer_ctl_set_array(struct mixer_ctl *ctl, const void *array, size_t count)
441 {
442     struct snd_ctl_elem_value ev;
443     size_t size;
444     void *dest;
445 
446     if (!ctl || (count > ctl->info->count) || !count || !array)
447         return -EINVAL;
448 
449     memset(&ev, 0, sizeof(ev));
450     ev.id.numid = ctl->info->id.numid;
451 
452     switch (ctl->info->type) {
453     case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
454     case SNDRV_CTL_ELEM_TYPE_INTEGER:
455         size = sizeof(ev.value.integer.value[0]);
456         dest = ev.value.integer.value;
457         break;
458 
459     case SNDRV_CTL_ELEM_TYPE_BYTES:
460         /* check if this is new bytes TLV */
461         if (ctl->info->access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
462             struct snd_ctl_tlv *tlv;
463             int ret = 0;
464             if (count > SIZE_MAX - sizeof(*tlv))
465                 return -EINVAL;
466             tlv = calloc(1, sizeof(*tlv) + count);
467             if (!tlv)
468                 return -ENOMEM;
469             tlv->numid = ctl->info->id.numid;
470             tlv->length = count;
471             memcpy(tlv->tlv, array, count);
472 
473             ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_TLV_WRITE, tlv);
474             free(tlv);
475 
476             return ret;
477         } else {
478             size = sizeof(ev.value.bytes.data[0]);
479             dest = ev.value.bytes.data;
480         }
481         break;
482 
483     case SNDRV_CTL_ELEM_TYPE_IEC958:
484         size = sizeof(ev.value.iec958);
485         dest = &ev.value.iec958;
486         break;
487 
488     default:
489         return -EINVAL;
490     }
491 
492     memcpy(dest, array, size * count);
493 
494     return ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev);
495 }
496 
mixer_ctl_get_range_min(struct mixer_ctl * ctl)497 int mixer_ctl_get_range_min(struct mixer_ctl *ctl)
498 {
499     if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER))
500         return -EINVAL;
501 
502     return ctl->info->value.integer.min;
503 }
504 
mixer_ctl_get_range_max(struct mixer_ctl * ctl)505 int mixer_ctl_get_range_max(struct mixer_ctl *ctl)
506 {
507     if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER))
508         return -EINVAL;
509 
510     return ctl->info->value.integer.max;
511 }
512 
mixer_ctl_get_num_enums(struct mixer_ctl * ctl)513 unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl)
514 {
515     if (!ctl)
516         return 0;
517 
518     return ctl->info->value.enumerated.items;
519 }
520 
mixer_ctl_get_enum_string(struct mixer_ctl * ctl,unsigned int enum_id)521 const char *mixer_ctl_get_enum_string(struct mixer_ctl *ctl,
522                                       unsigned int enum_id)
523 {
524     if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_ENUMERATED) ||
525         (enum_id >= ctl->info->value.enumerated.items))
526         return NULL;
527 
528     return (const char *)ctl->ename[enum_id];
529 }
530 
mixer_ctl_set_enum_by_string(struct mixer_ctl * ctl,const char * string)531 int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string)
532 {
533     unsigned int i, num_enums;
534     struct snd_ctl_elem_value ev;
535     int ret;
536 
537     if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_ENUMERATED))
538         return -EINVAL;
539 
540     num_enums = ctl->info->value.enumerated.items;
541     for (i = 0; i < num_enums; i++) {
542         if (!strcmp(string, ctl->ename[i])) {
543             memset(&ev, 0, sizeof(ev));
544             ev.value.enumerated.item[0] = i;
545             ev.id.numid = ctl->info->id.numid;
546             ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev);
547             if (ret < 0)
548                 return ret;
549             return 0;
550         }
551     }
552 
553     return -EINVAL;
554 }
555 
556