nils/shairport-sync
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Alsa output driver

Browse Source 
Based on a bit of code of @Skaman and bit of mine, I've added support
for mixer and audio Alsa support.
This commit is contained in:
Muffinman
2013-06-20 18:30:42 +10:00
committed by James Laird
parent 9340e5b897
commit 95035f3389
4 changed files with 216 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Makefile
+5 -1
View File
@@ -16,7 +16,11 @@ SRCS += audio_ao.c
endif
ifdef CONFIG_PULSE
SRCS += audio_pulse.c
SRCS += audio_pulse.c
endif
ifdef CONFIG_ALSA
SRCS += audio_alsa.c
endif
ifdef CONFIG_AVAHI
audio.c
+6
View File
@@ -35,9 +35,15 @@ extern audio_output audio_ao;
#ifdef CONFIG_PULSE
extern audio_output audio_pulse;
#endif
#ifdef CONFIG_ALSA
extern audio_output audio_alsa;
#endif
extern audio_output audio_dummy, audio_pipe;
static audio_output *outputs[] = {
#ifdef CONFIG_ALSA
&audio_alsa,
#endif
#ifdef CONFIG_PULSE
&audio_pulse,
#endif
audio_alsa.c
+195
View File
@@ -0,0 +1,195 @@
/*
* libalsa output driver. This file is part of Shairport.
* Copyright (c) Muffinman, Skaman 2013
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
#define ALSA_PCM_NEW_HW_PARAMS_API
#include <stdio.h>
#include <unistd.h>
#include <memory.h>
#include <alsa/asoundlib.h>
#include "common.h"
#include "audio.h"
static void help(void);
static int init(int argc, char **argv);
static void deinit(void);
static void start(int sample_rate);
static void play(short buf[], int samples);
static void stop(void);
static void volume(double vol);
audio_output audio_alsa = {
.name = "alsa",
.help = &help,
.init = &init,
.deinit = &deinit,
.start = &start,
.stop = &stop,
.play = &play,
.volume = NULL
};
static snd_pcm_t *alsa_handle = NULL;
static snd_pcm_hw_params_t *alsa_params = NULL;
static snd_mixer_t *alsa_mix_handle = NULL;
static snd_mixer_elem_t *alsa_mix_elem = NULL;
static snd_mixer_selem_id_t *alsa_mix_sid = NULL;
static long alsa_mix_minv, alsa_mix_range;
static char *alsa_out_dev = "default";
static char *alsa_mix_dev = NULL;
static char *alsa_mix_ctrl = "Master";
static int alsa_mix_index = 0;
static void help(void) {
printf(" -d output-device set the output device [default*|...]\n"
" -t mixer-type set the mixer type [software*|hardware]\n"
" -m mixer-device set the mixer device ['output-device'*|...]\n"
" -c mixer-control set the mixer control [Master*|...]\n"
" -i mixer-index set the mixer index [0*|...]\n"
" *) default option\n"
);
}
static int init(int argc, char **argv) {
int hardware_mixer = 0;
optind = 1; // optind=0 is equivalent to optind=1 plus special behaviour
argv--; // so we shift the arguments to satisfy getopt()
argc++;
// some platforms apparently require optreset = 1; - which?
int opt;
while ((opt = getopt(argc, argv, "d:t:m:c:i:")) > 0) {
switch (opt) {
case 'd':
alsa_out_dev = optarg;
break;
case 't':
if (strcmp(optarg, "hardware") == 0)
hardware_mixer = 1;
break;
case 'm':
alsa_mix_dev = optarg;
break;
case 'c':
alsa_mix_ctrl = optarg;
break;
case 'i':
alsa_mix_index = strtol(optarg, NULL, 10);
break;
default:
help();
die("Invalid audio option -%c specified", opt);
}
}
if (optind < argc)
die("Invalid audio argument: %s", argv[optind]);
if (!hardware_mixer)
return 0;
if (alsa_mix_dev == NULL)
alsa_mix_dev = alsa_out_dev;
audio_alsa.volume = &volume;
int ret = 0;
long alsa_mix_maxv;
snd_mixer_selem_id_alloca(&alsa_mix_sid);
snd_mixer_selem_id_set_index(alsa_mix_sid, alsa_mix_index);
snd_mixer_selem_id_set_name(alsa_mix_sid, alsa_mix_ctrl);
if ((snd_mixer_open(&alsa_mix_handle, 0)) < 0)
die ("Failed to open mixer");
if ((snd_mixer_attach(alsa_mix_handle, alsa_mix_dev)) < 0)
die ("Failed to attach mixer");
if ((snd_mixer_selem_register(alsa_mix_handle, NULL, NULL)) < 0)
die ("Failed to register mixer element");
ret = snd_mixer_load(alsa_mix_handle);
if (ret < 0)
die ("Failed to load mixer element");
alsa_mix_elem = snd_mixer_find_selem(alsa_mix_handle, alsa_mix_sid);
if (!alsa_mix_elem)
die ("Failed to find mixer element");
snd_mixer_selem_get_playback_volume_range (alsa_mix_elem, &alsa_mix_minv, &alsa_mix_maxv);
alsa_mix_range = alsa_mix_maxv - alsa_mix_minv;
return 0;
}
static void deinit(void) {
stop();
if (alsa_mix_handle) {
snd_mixer_close(alsa_mix_handle);
}
}
static void start(int sample_rate) {
if (sample_rate != 44100)
die("Unexpected sample rate!");
int ret, dir = 0;
snd_pcm_uframes_t frames = 64;
ret = snd_pcm_open(&alsa_handle, alsa_out_dev, SND_PCM_STREAM_PLAYBACK, 0);
if (ret < 0)
die("Alsa initialization failed: unable to open pcm device: %s\n", snd_strerror(ret));
snd_pcm_hw_params_alloca(&alsa_params);
snd_pcm_hw_params_any(alsa_handle, alsa_params);
snd_pcm_hw_params_set_access(alsa_handle, alsa_params, SND_PCM_ACCESS_RW_INTERLEAVED);
snd_pcm_hw_params_set_format(alsa_handle, alsa_params, SND_PCM_FORMAT_S16);
snd_pcm_hw_params_set_channels(alsa_handle, alsa_params, 2);
snd_pcm_hw_params_set_rate_near(alsa_handle, alsa_params, (unsigned int *)&sample_rate, &dir);
snd_pcm_hw_params_set_period_size_near(alsa_handle, alsa_params, &frames, &dir);
ret = snd_pcm_hw_params(alsa_handle, alsa_params);
if (ret < 0)
die("unable to set hw parameters: %s\n", snd_strerror(ret));
}
static void play(short buf[], int samples) {
int err = snd_pcm_writei(alsa_handle, (char*)buf, samples);
if (err < 0)
err = snd_pcm_recover(alsa_handle, err, 0);
if (err < 0)
die("Failed to write to PCM device: %s\n", snd_strerror(err));
}
static void stop(void) {
if (alsa_handle) {
snd_pcm_drain(alsa_handle);
snd_pcm_close(alsa_handle);
alsa_handle = NULL;
}
}
static void volume(double vol) {
long alsa_volume = (vol*alsa_mix_range)+alsa_mix_minv;
if(snd_mixer_selem_set_playback_volume_all(alsa_mix_elem, alsa_volume) != 0)
die ("Failed to set playback volume");
}
configure
Vendored
+10
View File
@@ -43,6 +43,16 @@ else
echo libpulse or its dev package not found
fi
if pkg-config alsa 2>/dev/null; then
CFLAGS="${CFLAGS} `pkg-config --cflags alsa`"
LDFLAGS="${LDFLAGS} `pkg-config --libs alsa`"
echo "#define CONFIG_ALSA" >> config.h
echo "CONFIG_ALSA=yes" >> config.mk
echo libalsa found
else
echo libalsa or its dev package not found
fi
if pkg-config avahi-client 2>/dev/null; then
CFLAGS="${CFLAGS} `pkg-config --cflags avahi-client`"
LDFLAGS="${LDFLAGS} `pkg-config --libs avahi-client`"