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-rw-r--r--src/mixer/alsa_mixer_plugin.c239
1 files changed, 239 insertions, 0 deletions
diff --git a/src/mixer/alsa_mixer_plugin.c b/src/mixer/alsa_mixer_plugin.c
new file mode 100644
index 000000000..baf12030c
--- /dev/null
+++ b/src/mixer/alsa_mixer_plugin.c
@@ -0,0 +1,239 @@
+/*
+ * Copyright (C) 2003-2009 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * 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 2 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, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "mixer_api.h"
+#include "output_api.h"
+
+#include <glib.h>
+#include <alsa/asoundlib.h>
+
+#define VOLUME_MIXER_ALSA_DEFAULT "default"
+#define VOLUME_MIXER_ALSA_CONTROL_DEFAULT "PCM"
+#define VOLUME_MIXER_ALSA_INDEX_DEFAULT 0
+
+struct alsa_mixer {
+ /** the base mixer class */
+ struct mixer base;
+
+ const char *device;
+ const char *control;
+ unsigned int index;
+
+ snd_mixer_t *handle;
+ snd_mixer_elem_t *elem;
+ long volume_min;
+ long volume_max;
+ int volume_set;
+};
+
+/**
+ * The quark used for GError.domain.
+ */
+static inline GQuark
+alsa_mixer_quark(void)
+{
+ return g_quark_from_static_string("alsa_mixer");
+}
+
+static struct mixer *
+alsa_mixer_init(G_GNUC_UNUSED void *ao, const struct config_param *param,
+ G_GNUC_UNUSED GError **error_r)
+{
+ struct alsa_mixer *am = g_new(struct alsa_mixer, 1);
+
+ mixer_init(&am->base, &alsa_mixer_plugin);
+
+ am->device = config_get_block_string(param, "mixer_device",
+ VOLUME_MIXER_ALSA_DEFAULT);
+ am->control = config_get_block_string(param, "mixer_control",
+ VOLUME_MIXER_ALSA_CONTROL_DEFAULT);
+ am->index = config_get_block_unsigned(param, "mixer_index",
+ VOLUME_MIXER_ALSA_INDEX_DEFAULT);
+
+ return &am->base;
+}
+
+static void
+alsa_mixer_finish(struct mixer *data)
+{
+ struct alsa_mixer *am = (struct alsa_mixer *)data;
+
+ g_free(am);
+
+ /* free libasound's config cache */
+ snd_config_update_free_global();
+}
+
+static void
+alsa_mixer_close(struct mixer *data)
+{
+ struct alsa_mixer *am = (struct alsa_mixer *)data;
+
+ assert(am->handle != NULL);
+
+ snd_mixer_close(am->handle);
+}
+
+static bool
+alsa_mixer_open(struct mixer *data, GError **error_r)
+{
+ struct alsa_mixer *am = (struct alsa_mixer *)data;
+ int err;
+ snd_mixer_elem_t *elem;
+
+ am->volume_set = -1;
+
+ err = snd_mixer_open(&am->handle, 0);
+ if (err < 0) {
+ g_set_error(error_r, alsa_mixer_quark(), err,
+ "snd_mixer_open() failed: %s", snd_strerror(err));
+ return false;
+ }
+
+ if ((err = snd_mixer_attach(am->handle, am->device)) < 0) {
+ alsa_mixer_close(data);
+ g_set_error(error_r, alsa_mixer_quark(), err,
+ "failed to attach to %s: %s",
+ am->device, snd_strerror(err));
+ return false;
+ }
+
+ if ((err = snd_mixer_selem_register(am->handle, NULL,
+ NULL)) < 0) {
+ alsa_mixer_close(data);
+ g_set_error(error_r, alsa_mixer_quark(), err,
+ "snd_mixer_selem_register() failed: %s",
+ snd_strerror(err));
+ return false;
+ }
+
+ if ((err = snd_mixer_load(am->handle)) < 0) {
+ alsa_mixer_close(data);
+ g_set_error(error_r, alsa_mixer_quark(), err,
+ "snd_mixer_load() failed: %s\n",
+ snd_strerror(err));
+ return false;
+ }
+
+ elem = snd_mixer_first_elem(am->handle);
+
+ while (elem) {
+ if (snd_mixer_elem_get_type(elem) == SND_MIXER_ELEM_SIMPLE) {
+ if ((g_ascii_strcasecmp(am->control,
+ snd_mixer_selem_get_name(elem)) == 0) &&
+ (am->index == snd_mixer_selem_get_index(elem))) {
+ break;
+ }
+ }
+ elem = snd_mixer_elem_next(elem);
+ }
+
+ if (elem) {
+ am->elem = elem;
+ snd_mixer_selem_get_playback_volume_range(am->elem,
+ &am->volume_min,
+ &am->volume_max);
+ return true;
+ }
+
+ alsa_mixer_close(data);
+ g_set_error(error_r, alsa_mixer_quark(), 0,
+ "no such mixer control: %s", am->control);
+ return false;
+}
+
+static int
+alsa_mixer_get_volume(struct mixer *mixer, GError **error_r)
+{
+ struct alsa_mixer *am = (struct alsa_mixer *)mixer;
+ int err;
+ int ret;
+ long level;
+
+ assert(am->handle != NULL);
+
+ err = snd_mixer_handle_events(am->handle);
+ if (err < 0) {
+ g_set_error(error_r, alsa_mixer_quark(), err,
+ "snd_mixer_handle_events() failed: %s",
+ snd_strerror(err));
+ return false;
+ }
+
+ err = snd_mixer_selem_get_playback_volume(am->elem,
+ SND_MIXER_SCHN_FRONT_LEFT,
+ &level);
+ if (err < 0) {
+ g_set_error(error_r, alsa_mixer_quark(), err,
+ "failed to read ALSA volume: %s",
+ snd_strerror(err));
+ return false;
+ }
+
+ ret = ((am->volume_set / 100.0) * (am->volume_max - am->volume_min)
+ + am->volume_min) + 0.5;
+ if (am->volume_set > 0 && ret == level) {
+ ret = am->volume_set;
+ } else {
+ ret = (int)(100 * (((float)(level - am->volume_min)) /
+ (am->volume_max - am->volume_min)) + 0.5);
+ }
+
+ return ret;
+}
+
+static bool
+alsa_mixer_set_volume(struct mixer *mixer, unsigned volume, GError **error_r)
+{
+ struct alsa_mixer *am = (struct alsa_mixer *)mixer;
+ float vol;
+ long level;
+ int err;
+
+ assert(am->handle != NULL);
+
+ vol = volume;
+
+ am->volume_set = vol + 0.5;
+
+ level = (long)(((vol / 100.0) * (am->volume_max - am->volume_min) +
+ am->volume_min) + 0.5);
+ level = level > am->volume_max ? am->volume_max : level;
+ level = level < am->volume_min ? am->volume_min : level;
+
+ err = snd_mixer_selem_set_playback_volume_all(am->elem, level);
+ if (err < 0) {
+ g_set_error(error_r, alsa_mixer_quark(), err,
+ "failed to set ALSA volume: %s",
+ snd_strerror(err));
+ return false;
+ }
+
+ return true;
+}
+
+const struct mixer_plugin alsa_mixer_plugin = {
+ .init = alsa_mixer_init,
+ .finish = alsa_mixer_finish,
+ .open = alsa_mixer_open,
+ .close = alsa_mixer_close,
+ .get_volume = alsa_mixer_get_volume,
+ .set_volume = alsa_mixer_set_volume,
+ .global = true,
+};