/* * Copyright (C) 2015 "IoT.bzh" * Author "Manuel Bachmann" * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include "audio-api.h" #include "audio-alsa.h" PUBLIC unsigned char _alsa_init (const char *name, audioCtxHandleT *ctx) { snd_pcm_t *dev; snd_pcm_hw_params_t *params; snd_mixer_t *mixer; snd_mixer_selem_id_t *mixer_sid; snd_mixer_elem_t *mixer_elm; unsigned int rate = 22050; long vol, vol_min, vol_max; int num; if (snd_pcm_open (&dev, name, SND_PCM_STREAM_PLAYBACK, 0) < 0) return 0; snd_pcm_hw_params_malloc (¶ms); snd_pcm_hw_params_any (dev, params); snd_pcm_hw_params_set_access (dev, params, SND_PCM_ACCESS_RW_INTERLEAVED); snd_pcm_hw_params_set_format (dev, params, SND_PCM_FORMAT_S16_LE); snd_pcm_hw_params_set_rate_near (dev, params, &rate, 0); snd_pcm_hw_params_set_channels (dev, params, ctx->channels); if (snd_pcm_hw_params (dev, params) < 0) { snd_pcm_hw_params_free (params); return 0; } snd_pcm_prepare (dev); snd_mixer_open (&mixer, 0); if (snd_mixer_attach (mixer, name) < 0) { snd_pcm_hw_params_free (params); return 0; } snd_mixer_selem_register (mixer, NULL, NULL); snd_mixer_load (mixer); snd_mixer_selem_id_alloca (&mixer_sid); snd_mixer_selem_id_set_index (mixer_sid, 0); snd_mixer_selem_id_set_name (mixer_sid, "Master"); mixer_elm = snd_mixer_find_selem (mixer, mixer_sid); if (mixer_elm) { snd_mixer_selem_get_playback_volume_range (mixer_elm, &vol_min, &vol_max); snd_mixer_selem_get_playback_volume (mixer_elm, SND_MIXER_SCHN_FRONT_LEFT, &vol); } /* allocate the global array if it hasn't been done */ if (!adev_ctx) { adev_ctx = (adev_ctx_T**) malloc (sizeof(adev_ctx_T)); adev_ctx[0] = (adev_ctx_T*) malloc (sizeof(adev_ctx_T)); adev_ctx[0]->name = NULL; adev_ctx[0]->dev = NULL; } /* is a card with similar name already opened ? */ for (num = 0; num < (sizeof(adev_ctx)/sizeof(adev_ctx_T)); num++) { if (adev_ctx[num]->name && !strcmp (adev_ctx[num]->name, name)) return 0; } num++; /* it's not... let us add it to the global array */ adev_ctx = (adev_ctx_T**) realloc (adev_ctx, (num+1)*sizeof(adev_ctx_T)); adev_ctx[num] = (adev_ctx_T*) malloc (sizeof(adev_ctx_T)); adev_ctx[num]->name = strdup (name); adev_ctx[num]->dev = dev; adev_ctx[num]->params = params; adev_ctx[num]->mixer_elm = mixer_elm; adev_ctx[num]->vol_max = vol_max; adev_ctx[num]->vol = vol; /* make the client context aware of current card state */ ctx->volume = _alsa_get_volume (num); ctx->mute = _alsa_get_mute (num); ctx->idx = num; return 1; } PUBLIC void _alsa_free (const char *name) { int num; for (num = 0; num < (sizeof(adev_ctx)/sizeof(adev_ctx_T)); num++) { if (adev_ctx[num]->name && !strcmp (adev_ctx[num]->name, name)) { snd_pcm_close (adev_ctx[num]->dev); snd_pcm_hw_params_free (adev_ctx[num]->params); free (adev_ctx[num]->name); adev_ctx[num]->name = NULL; adev_ctx[num]->dev = NULL; free(adev_ctx[num]); return; } } } PUBLIC void _alsa_play (unsigned int num, void *buf, int len) { if (!adev_ctx || !adev_ctx[num]) { return; } int16_t *cbuf = (int16_t *)buf; int frames = len / 2; int res; if ((res = snd_pcm_writei (adev_ctx[num]->dev, cbuf, frames)) != frames) { snd_pcm_recover (adev_ctx[num]->dev, res, 0); snd_pcm_prepare (adev_ctx[num]->dev); } /* snd_pcm_drain (adev_ctx[num]->dev); */ } PUBLIC unsigned int _alsa_get_volume (unsigned int num) { if (!adev_ctx || !adev_ctx[num] || !adev_ctx[num]->mixer_elm) return; snd_mixer_selem_get_playback_volume (adev_ctx[num]->mixer_elm, SND_MIXER_SCHN_FRONT_LEFT, &adev_ctx[num]->vol); return (unsigned int)(adev_ctx[num]->vol*100)/adev_ctx[num]->vol_max; } PUBLIC unsigned int _alsa_set_volume (unsigned int num, unsigned int vol) { if (!adev_ctx || !adev_ctx[num] || !adev_ctx[num]->mixer_elm || vol > 100) return; snd_mixer_selem_set_playback_volume_all (adev_ctx[num]->mixer_elm, (vol*adev_ctx[num]->vol_max)/100); } PUBLIC unsigned char _alsa_get_mute (unsigned int num) { int mute = 0; if (!adev_ctx || !adev_ctx[num] || !adev_ctx[num]->mixer_elm) return; if (snd_mixer_selem_has_playback_switch (adev_ctx[num]->mixer_elm)) { snd_mixer_selem_get_playback_switch (adev_ctx[num]->mixer_elm, SND_MIXER_SCHN_FRONT_LEFT, &mute); snd_mixer_selem_get_playback_switch (adev_ctx[num]->mixer_elm, SND_MIXER_SCHN_FRONT_RIGHT, &mute); } return (unsigned char)!mute; } PUBLIC void _alsa_set_mute (unsigned int num, unsigned char mute) { if (!adev_ctx || !adev_ctx[num] || !adev_ctx[num]->mixer_elm || 1 < mute < 0) return; if (snd_mixer_selem_has_playback_switch (adev_ctx[num]->mixer_elm)) snd_mixer_selem_set_playback_switch_all (adev_ctx[num]->mixer_elm, !mute); } PUBLIC void _alsa_set_rate (unsigned int num, unsigned int rate) { if (!adev_ctx || !adev_ctx[num]) return; snd_pcm_hw_params_set_rate_near (adev_ctx[num]->dev, adev_ctx[num]->params, &rate, 0); } PUBLIC void _alsa_set_channels (unsigned int num, unsigned int channels) { if (!adev_ctx || !adev_ctx[num]) return; snd_pcm_hw_params_set_channels (adev_ctx[num]->dev, adev_ctx[num]->params, channels); }