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 PUBLIC unsigned char _alsa_init (const char *name, audioCtxHandleT *ctx) {
25 snd_pcm_hw_params_t *params;
27 snd_mixer_selem_id_t *mixer_sid;
28 snd_mixer_elem_t *mixer_elm;
29 unsigned int rate = 22050;
30 long vol, vol_min, vol_max;
33 if (snd_pcm_open (&dev, name, SND_PCM_STREAM_PLAYBACK, 0) < 0)
36 snd_pcm_hw_params_malloc (¶ms);
37 snd_pcm_hw_params_any (dev, params);
38 snd_pcm_hw_params_set_access (dev, params, SND_PCM_ACCESS_RW_INTERLEAVED);
39 snd_pcm_hw_params_set_format (dev, params, SND_PCM_FORMAT_S16_LE);
40 snd_pcm_hw_params_set_rate_near (dev, params, &rate, 0);
41 snd_pcm_hw_params_set_channels (dev, params, ctx->channels);
42 if (snd_pcm_hw_params (dev, params) < 0) {
43 snd_pcm_hw_params_free (params);
46 snd_pcm_prepare (dev);
48 snd_mixer_open (&mixer, 0);
49 if (snd_mixer_attach (mixer, name) < 0) {
50 snd_pcm_hw_params_free (params);
53 snd_mixer_selem_register (mixer, NULL, NULL);
54 snd_mixer_load (mixer);
56 snd_mixer_selem_id_alloca (&mixer_sid);
57 snd_mixer_selem_id_set_index (mixer_sid, 0);
58 snd_mixer_selem_id_set_name (mixer_sid, "Master");
60 mixer_elm = snd_mixer_find_selem (mixer, mixer_sid);
62 /* no "Master" mixer ; we are probably on a board... search ! */
63 for (mixer_elm = snd_mixer_first_elem (mixer); mixer_elm != NULL;
64 mixer_elm = snd_mixer_elem_next (mixer_elm)) {
65 if (snd_mixer_elem_info (mixer_elm) < 0)
67 snd_mixer_selem_get_id (mixer_elm, mixer_sid);
68 if (strstr (snd_mixer_selem_id_get_name (mixer_sid), "Master") ||
69 strstr (snd_mixer_selem_id_get_name (mixer_sid), "Playback"))
75 snd_mixer_selem_get_playback_volume_range (mixer_elm, &vol_min, &vol_max);
76 snd_mixer_selem_get_playback_volume (mixer_elm, SND_MIXER_SCHN_FRONT_LEFT, &vol);
79 /* allocate the global array if it hasn't been done */
81 dev_ctx = (dev_ctx_T**) malloc (sizeof(dev_ctx_T));
82 dev_ctx[0] = (dev_ctx_T*) malloc (sizeof(dev_ctx_T));
83 dev_ctx[0]->name = NULL;
84 dev_ctx[0]->dev = NULL;
87 /* is a card with similar name already opened ? */
88 for (num = 0; num < (sizeof(dev_ctx)/sizeof(dev_ctx_T)); num++) {
89 if (dev_ctx[num]->name &&
90 !strcmp (dev_ctx[num]->name, name))
95 /* it's not... let us add it to the global array */
96 dev_ctx = (dev_ctx_T**) realloc (dev_ctx, (num+1)*sizeof(dev_ctx_T));
97 dev_ctx[num] = (dev_ctx_T*) malloc (sizeof(dev_ctx_T));
98 dev_ctx[num]->name = strdup (name);
99 dev_ctx[num]->dev = dev;
100 dev_ctx[num]->params = params;
101 dev_ctx[num]->mixer_elm = mixer_elm;
102 dev_ctx[num]->vol_max = vol_max;
103 dev_ctx[num]->vol = vol;
104 dev_ctx[num]->thr_should_run = 0;
105 dev_ctx[num]->thr_finished = 0;
107 /* make the client context aware of current card state */
108 ctx->volume = _alsa_get_volume (num);
109 ctx->mute = _alsa_get_mute (num);
115 PUBLIC void _alsa_free (const char *name) {
119 for (num = 0; num < (sizeof(dev_ctx)/sizeof(dev_ctx_T)); num++) {
120 if (dev_ctx[num]->name &&
121 !strcmp (dev_ctx[num]->name, name)) {
122 snd_pcm_close (dev_ctx[num]->dev);
123 snd_pcm_hw_params_free (dev_ctx[num]->params);
124 free (dev_ctx[num]->name);
125 dev_ctx[num]->name = NULL;
126 dev_ctx[num]->dev = NULL;
133 PUBLIC void _alsa_play (unsigned int num) {
135 if (!dev_ctx || !dev_ctx[num] || dev_ctx[num]->thr_should_run ||
136 access (AUDIO_BUFFER, F_OK) == -1)
139 dev_ctx[num]->thr_should_run = 1;
140 dev_ctx[num]->thr_finished = 0;
141 pthread_create(&dev_ctx[num]->thr, NULL, _play_thread_fn, (void*)dev_ctx[num]);
144 PUBLIC void _alsa_stop (unsigned int num) {
146 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->thr_should_run)
149 /* stop the "while" loop in thread */
150 dev_ctx[num]->thr_should_run = 0;
152 while (!dev_ctx[num]->thr_finished)
155 pthread_join(dev_ctx[num]->thr, NULL);
158 PUBLIC unsigned int _alsa_get_volume (unsigned int num) {
160 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm)
163 snd_mixer_selem_get_playback_volume (dev_ctx[num]->mixer_elm, SND_MIXER_SCHN_FRONT_LEFT, &dev_ctx[num]->vol);
165 return (unsigned int)(dev_ctx[num]->vol*100)/dev_ctx[num]->vol_max;
168 PUBLIC unsigned int _alsa_set_volume (unsigned int num, unsigned int vol) {
170 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm || vol > 100)
173 snd_mixer_selem_set_playback_volume_all (dev_ctx[num]->mixer_elm, (vol*dev_ctx[num]->vol_max)/100);
176 PUBLIC unsigned char _alsa_get_mute (unsigned int num) {
180 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm)
183 if (snd_mixer_selem_has_playback_switch (dev_ctx[num]->mixer_elm)) {
184 snd_mixer_selem_get_playback_switch (dev_ctx[num]->mixer_elm, SND_MIXER_SCHN_FRONT_LEFT, &mute);
185 snd_mixer_selem_get_playback_switch (dev_ctx[num]->mixer_elm, SND_MIXER_SCHN_FRONT_RIGHT, &mute);
189 return (unsigned char)!mute;
192 PUBLIC void _alsa_set_mute (unsigned int num, unsigned char mute) {
194 if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm || 1 < mute < 0)
197 if (snd_mixer_selem_has_playback_switch (dev_ctx[num]->mixer_elm))
198 snd_mixer_selem_set_playback_switch_all (dev_ctx[num]->mixer_elm, !mute);
201 PUBLIC void _alsa_set_rate (unsigned int num, unsigned int rate) {
203 if (!dev_ctx || !dev_ctx[num])
206 snd_pcm_hw_params_set_rate_near (dev_ctx[num]->dev, dev_ctx[num]->params, &rate, 0);
209 PUBLIC void _alsa_set_channels (unsigned int num, unsigned int channels) {
211 if (!dev_ctx || !dev_ctx[num])
214 snd_pcm_hw_params_set_channels (dev_ctx[num]->dev, dev_ctx[num]->params, channels);
217 /* ---- LOCAL THREADED FUNCTIONS ---- */
219 STATIC void* _play_thread_fn (void *ctx) {
221 dev_ctx_T *dev_ctx = (dev_ctx_T *)ctx;
227 file = fopen (AUDIO_BUFFER, "rb");
229 while (dev_ctx->thr_should_run && file && (access (AUDIO_BUFFER, F_OK) != -1) ) {
230 fseek (file, 0, SEEK_END);
232 buf = (char*) realloc (buf, size * sizeof(char));
233 frames = (size * sizeof(char)) / 4;
235 fseek (file, 0, SEEK_SET);
236 fread (buf, 1, size, file);
239 if ((res = snd_pcm_writei (dev_ctx->dev, buf, frames)) != frames) {
240 snd_pcm_recover (dev_ctx->dev, res, 0);
241 snd_pcm_prepare (dev_ctx->dev);
243 /* snd_pcm_drain (dev_ctx->dev); */
246 if (file) fclose(file);
248 dev_ctx->thr_finished = 1;