2 * Copyright (C) 2015 "IoT.bzh"
3 * Author "Manuel Bachmann"
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
9 * http://www.apache.org/licenses/LICENSE-2.0
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
18 #include "audio-api.h"
19 #include "audio-alsa.h"
21 snd_mixer_selem_channel_id_t SCHANNELS[8] = {
22 SND_MIXER_SCHN_FRONT_LEFT,
23 SND_MIXER_SCHN_FRONT_RIGHT,
24 SND_MIXER_SCHN_FRONT_CENTER,
25 SND_MIXER_SCHN_REAR_LEFT,
26 SND_MIXER_SCHN_REAR_RIGHT,
27 SND_MIXER_SCHN_REAR_CENTER,
28 SND_MIXER_SCHN_SIDE_LEFT,
29 SND_MIXER_SCHN_SIDE_RIGHT
32 PUBLIC unsigned char _alsa_init (const char *name, audioCtxHandleT *ctx) {
35 snd_pcm_hw_params_t *params;
37 snd_mixer_selem_id_t *mixer_sid;
38 snd_mixer_elem_t *mixer_elm;
39 snd_mixer_elem_t *mixer_elm_m;
40 unsigned int rate = 22050;
41 long vol, vol_min, vol_max;
44 if (snd_pcm_open (&dev, name, SND_PCM_STREAM_PLAYBACK, 0) < 0)
47 snd_pcm_hw_params_malloc (¶ms);
48 snd_pcm_hw_params_any (dev, params);
49 snd_pcm_hw_params_set_access (dev, params, SND_PCM_ACCESS_RW_INTERLEAVED);
50 snd_pcm_hw_params_set_format (dev, params, SND_PCM_FORMAT_S16_LE);
51 snd_pcm_hw_params_set_rate_near (dev, params, &rate, 0);
52 snd_pcm_hw_params_set_channels (dev, params, ctx->channels);
53 if (snd_pcm_hw_params (dev, params) < 0) {
54 snd_pcm_hw_params_free (params);
57 snd_pcm_prepare (dev);
59 snd_mixer_open (&mixer, 0);
60 if (snd_mixer_attach (mixer, name) < 0) {
61 snd_pcm_hw_params_free (params);
64 snd_mixer_selem_register (mixer, NULL, NULL);
65 snd_mixer_load (mixer);
67 snd_mixer_selem_id_alloca (&mixer_sid);
68 snd_mixer_selem_id_set_index (mixer_sid, 0);
69 snd_mixer_selem_id_set_name (mixer_sid, "Master");
71 mixer_elm = snd_mixer_find_selem (mixer, mixer_sid);
75 /* no "Master" mixer ; we are probably on a board... search ! */
76 for (mixer_elm = snd_mixer_first_elem (mixer); mixer_elm != NULL;
77 mixer_elm = snd_mixer_elem_next (mixer_elm)) {
78 if (snd_mixer_elem_info (mixer_elm) < 0)
80 snd_mixer_selem_get_id (mixer_elm, mixer_sid);
81 if (strstr (snd_mixer_selem_id_get_name (mixer_sid), "DVC Out")) {
83 /* this is Porter... let us found the specific mute switch */
84 snd_mixer_selem_id_set_index (mixer_sid, 0);
85 snd_mixer_selem_id_set_name (mixer_sid, "DVC Out Mute");
86 mixer_elm_m = snd_mixer_find_selem (mixer, mixer_sid);
94 snd_mixer_selem_get_playback_volume_range (mixer_elm, &vol_min, &vol_max);
95 snd_mixer_selem_get_playback_volume (mixer_elm, SND_MIXER_SCHN_FRONT_LEFT, &vol);
98 /* allocate the global array if it hasn't been done */
100 dev_ctx_a = (dev_ctx_alsa_T**) malloc (sizeof(dev_ctx_alsa_T));
101 dev_ctx_a[0] = (dev_ctx_alsa_T*) malloc (sizeof(dev_ctx_alsa_T));
102 dev_ctx_a[0]->name = NULL;
103 dev_ctx_a[0]->dev = NULL;
106 /* is a card with similar name already opened ? */
107 for (num = 0; num < (sizeof(dev_ctx_a)/sizeof(dev_ctx_alsa_T)); num++) {
108 if (dev_ctx_a[num]->name &&
109 !strcmp (dev_ctx_a[num]->name, name))
114 /* it's not... let us add it to the global array */
115 dev_ctx_a = (dev_ctx_alsa_T**) realloc (dev_ctx_a, (num+1)*sizeof(dev_ctx_alsa_T));
116 dev_ctx_a[num] = (dev_ctx_alsa_T*) malloc (sizeof(dev_ctx_alsa_T));
117 dev_ctx_a[num]->name = strdup (name);
118 dev_ctx_a[num]->dev = dev;
119 dev_ctx_a[num]->params = params;
120 dev_ctx_a[num]->mixer_elm = mixer_elm;
121 dev_ctx_a[num]->mixer_elm_m = mixer_elm_m;
122 dev_ctx_a[num]->vol_max = vol_max;
123 dev_ctx_a[num]->vol = vol;
124 dev_ctx_a[num]->thr_should_run = 0;
125 dev_ctx_a[num]->thr_finished = 0;
127 /* make the client context aware of current card state */
128 for (i = 0; i < 8; i++)
129 ctx->volume[i] = _alsa_get_volume (num, i);
130 ctx->mute = _alsa_get_mute (num);
132 ctx->name = strdup (name);
134 if (verbose) fprintf (stderr, "Successfully initialized ALSA backend.\n");
139 PUBLIC void _alsa_free (const char *name) {
143 for (num = 0; num < (sizeof(dev_ctx_a)/sizeof(dev_ctx_alsa_T)); num++) {
144 if (dev_ctx_a[num]->name &&
145 !strcmp (dev_ctx_a[num]->name, name)) {
146 snd_pcm_close (dev_ctx_a[num]->dev);
147 snd_pcm_hw_params_free (dev_ctx_a[num]->params);
148 free (dev_ctx_a[num]->name);
149 dev_ctx_a[num]->dev = NULL;
150 dev_ctx_a[num]->name = NULL;
151 free (dev_ctx_a[num]);
157 PUBLIC void _alsa_play (int num) {
159 if (!dev_ctx_a || !dev_ctx_a[num] || dev_ctx_a[num]->thr_should_run ||
160 access (AUDIO_BUFFER, F_OK) == -1)
163 dev_ctx_a[num]->thr_should_run = 1;
164 dev_ctx_a[num]->thr_finished = 0;
165 pthread_create (&dev_ctx_a[num]->thr, NULL, _alsa_play_thread_fn, (void*)dev_ctx_a[num]);
168 PUBLIC void _alsa_stop (int num) {
170 if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->thr_should_run)
173 /* stop the "while" loop in thread */
174 dev_ctx_a[num]->thr_should_run = 0;
176 while (!dev_ctx_a[num]->thr_finished)
179 pthread_join (dev_ctx_a[num]->thr, NULL);
182 PUBLIC unsigned int _alsa_get_volume (int num, unsigned int channel) {
184 if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm)
187 snd_mixer_selem_get_playback_volume (dev_ctx_a[num]->mixer_elm, SCHANNELS[channel], &dev_ctx_a[num]->vol);
189 return (int)(dev_ctx_a[num]->vol*100)/dev_ctx_a[num]->vol_max;
192 PUBLIC void _alsa_set_volume (int num, unsigned int channel, unsigned int vol) {
194 if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm ||
198 snd_mixer_selem_set_playback_volume (dev_ctx_a[num]->mixer_elm, SCHANNELS[channel], (vol*dev_ctx_a[num]->vol_max)/100);
202 PUBLIC void _alsa_set_volume_all (int num, unsigned int vol) {
204 if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm ||
207 snd_mixer_selem_set_playback_volume_all (dev_ctx_a[num]->mixer_elm, (vol*dev_ctx_a[num]->vol_max)/100);
210 PUBLIC unsigned char _alsa_get_mute (int num) {
213 snd_mixer_elem_t *elm_m;
215 if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm)
218 dev_ctx_a[num]->mixer_elm_m ? (elm_m = dev_ctx_a[num]->mixer_elm_m) :
219 (elm_m = dev_ctx_a[num]->mixer_elm);
221 if (snd_mixer_selem_has_playback_switch (elm_m)) {
222 snd_mixer_selem_get_playback_switch (elm_m, SND_MIXER_SCHN_FRONT_LEFT, &mute);
223 snd_mixer_selem_get_playback_switch (elm_m, SND_MIXER_SCHN_FRONT_RIGHT, &mute);
226 if (dev_ctx_a[num]->mixer_elm_m)
227 return (unsigned char)mute;
229 return (unsigned char)!mute;
232 PUBLIC void _alsa_set_mute (int num, unsigned char tomute) {
234 snd_mixer_elem_t *elm_m;
237 if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm || 1 < tomute)
240 if (dev_ctx_a[num]->mixer_elm_m) {
241 elm_m = dev_ctx_a[num]->mixer_elm_m;
244 elm_m = dev_ctx_a[num]->mixer_elm;
248 if (snd_mixer_selem_has_playback_switch (elm_m))
249 snd_mixer_selem_set_playback_switch_all (elm_m, !mute);
252 PUBLIC void _alsa_set_rate (int num, unsigned int rate) {
254 if (!dev_ctx_a || !dev_ctx_a[num])
257 snd_pcm_hw_params_set_rate_near (dev_ctx_a[num]->dev, dev_ctx_a[num]->params, &rate, 0);
260 PUBLIC void _alsa_set_channels (int num, unsigned int channels) {
262 if (!dev_ctx_a || !dev_ctx_a[num])
265 snd_pcm_hw_params_set_channels (dev_ctx_a[num]->dev, dev_ctx_a[num]->params, channels);
268 /* ---- LOCAL THREADED FUNCTIONS ---- */
270 STATIC void* _alsa_play_thread_fn (void *ctx) {
272 dev_ctx_alsa_T *dev_ctx_a = (dev_ctx_alsa_T *)ctx;
278 file = fopen (AUDIO_BUFFER, "rb");
280 while (dev_ctx_a->thr_should_run && file && (access (AUDIO_BUFFER, F_OK) != -1) ) {
281 fseek (file, 0, SEEK_END);
283 buf = (char*) realloc (buf, size * sizeof(char));
284 frames = (size * sizeof(char)) / 4;
286 fseek (file, 0, SEEK_SET);
287 fread (buf, 1, size, file);
290 if ((res = snd_pcm_writei (dev_ctx_a->dev, buf, frames)) != frames) {
291 snd_pcm_recover (dev_ctx_a->dev, res, 0);
292 snd_pcm_prepare (dev_ctx_a->dev);
294 /* snd_pcm_drain (dev_ctx->dev); */
297 if (file) fclose(file);
299 dev_ctx_a->thr_finished = 1;