2 * Copyright (C) 2015 "IoT.bzh"
3 * Author "Manuel Bachmann"
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
19 #include "audio-api.h"
20 #include "audio-alsa.h"
22 snd_mixer_selem_channel_id_t SCHANNELS[8] = {
23 SND_MIXER_SCHN_FRONT_LEFT,
24 SND_MIXER_SCHN_FRONT_RIGHT,
25 SND_MIXER_SCHN_FRONT_CENTER,
26 SND_MIXER_SCHN_REAR_LEFT,
27 SND_MIXER_SCHN_REAR_RIGHT,
28 SND_MIXER_SCHN_REAR_CENTER,
29 SND_MIXER_SCHN_SIDE_LEFT,
30 SND_MIXER_SCHN_SIDE_RIGHT
33 PUBLIC unsigned char _alsa_init (const char *name, audioCtxHandleT *ctx) {
36 snd_pcm_hw_params_t *params;
38 snd_mixer_selem_id_t *mixer_sid;
39 snd_mixer_elem_t *mixer_elm;
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);
73 /* no "Master" mixer ; we are probably on a board... search ! */
74 for (mixer_elm = snd_mixer_first_elem (mixer); mixer_elm != NULL;
75 mixer_elm = snd_mixer_elem_next (mixer_elm)) {
76 if (snd_mixer_elem_info (mixer_elm) < 0)
78 snd_mixer_selem_get_id (mixer_elm, mixer_sid);
79 if (strstr (snd_mixer_selem_id_get_name (mixer_sid), "Master") ||
80 strstr (snd_mixer_selem_id_get_name (mixer_sid), "Playback"))
86 snd_mixer_selem_get_playback_volume_range (mixer_elm, &vol_min, &vol_max);
87 snd_mixer_selem_get_playback_volume (mixer_elm, SND_MIXER_SCHN_FRONT_LEFT, &vol);
90 /* allocate the global array if it hasn't been done */
92 dev_ctx = (dev_ctx_T**) malloc (sizeof(dev_ctx_T));
93 dev_ctx[0] = (dev_ctx_T*) malloc (sizeof(dev_ctx_T));
94 dev_ctx[0]->name = NULL;
95 dev_ctx[0]->dev = NULL;
98 /* is a card with similar name already opened ? */
99 for (num = 0; num < (sizeof(dev_ctx)/sizeof(dev_ctx_T)); num++) {
100 if (dev_ctx[num]->name &&
101 !strcmp (dev_ctx[num]->name, name))
106 /* it's not... let us add it to the global array */
107 dev_ctx = (dev_ctx_T**) realloc (dev_ctx, (num+1)*sizeof(dev_ctx_T));
108 dev_ctx[num] = (dev_ctx_T*) malloc (sizeof(dev_ctx_T));
109 dev_ctx[num]->name = strdup (name);
110 dev_ctx[num]->dev = dev;
111 dev_ctx[num]->params = params;
112 dev_ctx[num]->mixer_elm = mixer_elm;
113 dev_ctx[num]->vol_max = vol_max;
114 dev_ctx[num]->vol = vol;
115 dev_ctx[num]->thr_should_run = 0;
116 dev_ctx[num]->thr_finished = 0;
118 /* make the client context aware of current card state */
119 for (i = 0; i < 8; i++)
120 ctx->volume[i] = _alsa_get_volume (num, i);
121 ctx->mute = _alsa_get_mute (num);
127 PUBLIC void _alsa_free (const char *name) {
131 for (num = 0; num < (sizeof(dev_ctx)/sizeof(dev_ctx_T)); num++) {
132 if (dev_ctx[num]->name &&
133 !strcmp (dev_ctx[num]->name, name)) {
134 snd_pcm_close (dev_ctx[num]->dev);
135 snd_pcm_hw_params_free (dev_ctx[num]->params);
136 free (dev_ctx[num]->name);
137 dev_ctx[num]->name = NULL;
138 dev_ctx[num]->dev = NULL;
145 PUBLIC void _alsa_play (unsigned int num) {
147 if (!dev_ctx || !dev_ctx[num] || dev_ctx[num]->thr_should_run ||
148 access (AUDIO_BUFFER, F_OK) == -1)
151 dev_ctx[num]->thr_should_run = 1;
152 dev_ctx[num]->thr_finished = 0;
153 pthread_create(&dev_ctx[num]->thr, NULL, _play_thread_fn, (void*)dev_ctx[num]);
156 PUBLIC void _alsa_stop (unsigned int num) {
158 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->thr_should_run)
161 /* stop the "while" loop in thread */
162 dev_ctx[num]->thr_should_run = 0;
164 while (!dev_ctx[num]->thr_finished)
167 pthread_join(dev_ctx[num]->thr, NULL);
170 PUBLIC int _alsa_get_volume (unsigned int num, unsigned int channel) {
172 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm)
175 snd_mixer_selem_get_playback_volume (dev_ctx[num]->mixer_elm, SCHANNELS[channel], &dev_ctx[num]->vol);
177 return (int)(dev_ctx[num]->vol*100)/dev_ctx[num]->vol_max;
180 PUBLIC void _alsa_set_volume (unsigned int num, unsigned int channel, int vol) {
182 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm ||
186 snd_mixer_selem_set_playback_volume (dev_ctx[num]->mixer_elm, SCHANNELS[channel], (vol*dev_ctx[num]->vol_max)/100);
190 PUBLIC void _alsa_set_volume_all (unsigned int num, int vol) {
192 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm ||
195 snd_mixer_selem_set_playback_volume_all (dev_ctx[num]->mixer_elm, (vol*dev_ctx[num]->vol_max)/100);
198 PUBLIC unsigned char _alsa_get_mute (unsigned int num) {
202 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm)
205 if (snd_mixer_selem_has_playback_switch (dev_ctx[num]->mixer_elm)) {
206 snd_mixer_selem_get_playback_switch (dev_ctx[num]->mixer_elm, SND_MIXER_SCHN_FRONT_LEFT, &mute);
207 snd_mixer_selem_get_playback_switch (dev_ctx[num]->mixer_elm, SND_MIXER_SCHN_FRONT_RIGHT, &mute);
211 return (unsigned char)!mute;
214 PUBLIC void _alsa_set_mute (unsigned int num, unsigned char mute) {
216 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm || 1 < mute < 0)
219 if (snd_mixer_selem_has_playback_switch (dev_ctx[num]->mixer_elm))
220 snd_mixer_selem_set_playback_switch_all (dev_ctx[num]->mixer_elm, !mute);
223 PUBLIC void _alsa_set_rate (unsigned int num, unsigned int rate) {
225 if (!dev_ctx || !dev_ctx[num])
228 snd_pcm_hw_params_set_rate_near (dev_ctx[num]->dev, dev_ctx[num]->params, &rate, 0);
231 PUBLIC void _alsa_set_channels (unsigned int num, unsigned int channels) {
233 if (!dev_ctx || !dev_ctx[num])
236 snd_pcm_hw_params_set_channels (dev_ctx[num]->dev, dev_ctx[num]->params, channels);
239 /* ---- LOCAL THREADED FUNCTIONS ---- */
241 STATIC void* _play_thread_fn (void *ctx) {
243 dev_ctx_T *dev_ctx = (dev_ctx_T *)ctx;
249 file = fopen (AUDIO_BUFFER, "rb");
251 while (dev_ctx->thr_should_run && file && (access (AUDIO_BUFFER, F_OK) != -1) ) {
252 fseek (file, 0, SEEK_END);
254 buf = (char*) realloc (buf, size * sizeof(char));
255 frames = (size * sizeof(char)) / 4;
257 fseek (file, 0, SEEK_SET);
258 fread (buf, 1, size, file);
261 if ((res = snd_pcm_writei (dev_ctx->dev, buf, frames)) != frames) {
262 snd_pcm_recover (dev_ctx->dev, res, 0);
263 snd_pcm_prepare (dev_ctx->dev);
265 /* snd_pcm_drain (dev_ctx->dev); */
268 if (file) fclose(file);
270 dev_ctx->thr_finished = 1;