4 files changed, 88 insertions, 6 deletions

diff --git a/src/filter/replay_gain_filter_plugin.c b/src/filter/replay_gain_filter_plugin.c
index 248690d17..c8e74c7fe 100644
--- a/src/filter/replay_gain_filter_plugin.c
+++ b/src/filter/replay_gain_filter_plugin.c
@@ -27,7 +27,9 @@
 #include "pcm_volume.h"
 #include "replay_gain_info.h"
 #include "replay_gain_config.h"
+#include "mixer_control.h"
 
+#include <assert.h>
 #include <string.h>
 
 #undef G_LOG_DOMAIN
@@ -36,6 +38,18 @@
 struct replay_gain_filter {
 	struct filter filter;
 
+	/**
+	 * If set, then this hardware mixer is used for applying
+	 * replay gain, instead of the software volume library.
+	 */
+	struct mixer *mixer;
+
+	/**
+	 * The base volume level for scale=1.0, between 1 and 100
+	 * (including).
+	 */
+	unsigned base;
+
 	enum replay_gain_mode mode;
 
 	struct replay_gain_info info;
@@ -74,6 +88,21 @@ replay_gain_filter_update(struct replay_gain_filter *filter)
 		filter->volume = pcm_float_to_volume(scale);
 	} else
 		filter->volume = PCM_VOLUME_1;
+
+	if (filter->mixer != NULL) {
+		/* update the hardware mixer volume */
+
+		unsigned volume = (filter->volume * filter->base) / PCM_VOLUME_1;
+		if (volume > 100)
+			volume = 100;
+
+		GError *error = NULL;
+		if (!mixer_set_volume(filter->mixer, volume, &error)) {
+			g_warning("Failed to update hardware mixer: %s",
+				  error->message);
+			g_error_free(error);
+		}
+	}
 }
 
 static struct filter *
@@ -83,6 +112,7 @@ replay_gain_filter_init(G_GNUC_UNUSED const struct config_param *param,
 	struct replay_gain_filter *filter = g_new(struct replay_gain_filter, 1);
 
 	filter_init(&filter->filter, &replay_gain_filter_plugin);
+	filter->mixer = NULL;
 
 	filter->mode = replay_gain_mode;
 	replay_gain_info_init(&filter->info);
@@ -178,6 +208,21 @@ const struct filter_plugin replay_gain_filter_plugin = {
 };
 
 void
+replay_gain_filter_set_mixer(struct filter *_filter, struct mixer *mixer,
+			     unsigned base)
+{
+	struct replay_gain_filter *filter =
+		(struct replay_gain_filter *)_filter;
+
+	assert(mixer == NULL || (base > 0 && base <= 100));
+
+	filter->mixer = mixer;
+	filter->base = base;
+
+	replay_gain_filter_update(filter);
+}
+
+void
 replay_gain_filter_set_info(struct filter *_filter,
 			    const struct replay_gain_info *info)
 {
diff --git a/src/filter/replay_gain_filter_plugin.h b/src/filter/replay_gain_filter_plugin.h
index 4ab9f42a6..348b4f50c 100644
--- a/src/filter/replay_gain_filter_plugin.h
+++ b/src/filter/replay_gain_filter_plugin.h
@@ -23,6 +23,19 @@
 #include "replay_gain_info.h"
 
 struct filter;
+struct mixer;
+
+/**
+ * Enables or disables the hardware mixer for applying replay gain.
+ *
+ * @param mixer the hardware mixer, or NULL to fall back to software
+ * volume
+ * @param base the base volume level for scale=1.0, between 1 and 100
+ * (including).
+ */
+void
+replay_gain_filter_set_mixer(struct filter *_filter, struct mixer *mixer,
+			     unsigned base);
 
 /**
  * Sets a new #replay_gain_info at the beginning of a new song.
diff --git a/src/output_init.c b/src/output_init.c
index 387915ddc..f3d22ace1 100644
--- a/src/output_init.c
+++ b/src/output_init.c
@@ -32,6 +32,7 @@
 #include "filter_config.h"
 #include "filter/chain_filter_plugin.h"
 #include "filter/autoconvert_filter_plugin.h"
+#include "filter/replay_gain_filter_plugin.h"
 
 #include <glib.h>
 
@@ -196,12 +197,19 @@ audio_output_init(struct audio_output *ao, const struct config_param *param,
 
 	/* create the replay_gain filter */
 
-	ao->replay_gain_filter = filter_new(&replay_gain_filter_plugin,
-					    param, NULL);
-	assert(ao->replay_gain_filter != NULL);
+	const char *replay_gain_handler =
+		config_get_block_string(param, "replay_gain_handler",
+					"software");
 
-	filter_chain_append(ao->filter, ao->replay_gain_filter);
-	ao->replay_gain_serial = 0;
+	if (strcmp(replay_gain_handler, "none") != 0) {
+		ao->replay_gain_filter = filter_new(&replay_gain_filter_plugin,
+						    param, NULL);
+		assert(ao->replay_gain_filter != NULL);
+
+		filter_chain_append(ao->filter, ao->replay_gain_filter);
+		ao->replay_gain_serial = 0;
+	} else
+		ao->replay_gain_filter = NULL;
 
 	/* create the normalization filter (if configured) */
 
@@ -247,6 +255,21 @@ audio_output_init(struct audio_output *ao, const struct config_param *param,
 		g_error_free(error);
 	}
 
+	/* use the hardware mixer for replay gain? */
+
+	if (strcmp(replay_gain_handler, "mixer") == 0) {
+		if (ao->mixer != NULL)
+			replay_gain_filter_set_mixer(ao->replay_gain_filter,
+						     ao->mixer, 100);
+		else
+			g_warning("No such mixer for output '%s'", ao->name);
+	} else if (strcmp(replay_gain_handler, "software") != 0 &&
+		   ao->replay_gain_filter != NULL) {
+		g_set_error(error_r, audio_output_quark(), 0,
+			    "Invalid \"replay_gain_handler\" value");
+		return false;
+	}
+
 	/* the "convert" filter must be the last one in the chain */
 
 	ao->convert_filter = filter_new(&convert_filter_plugin, NULL, NULL);
diff --git a/src/output_thread.c b/src/output_thread.c
index 0e34c64b7..4bf0827f6 100644
--- a/src/output_thread.c
+++ b/src/output_thread.c
@@ -264,7 +264,8 @@ ao_play_chunk(struct audio_output *ao, const struct music_chunk *chunk)
 
 	/* update replay gain */
 
-	if (chunk->replay_gain_serial != ao->replay_gain_serial) {
+	if (ao->replay_gain_filter != NULL &&
+	    chunk->replay_gain_serial != ao->replay_gain_serial) {
 		replay_gain_filter_set_info(ao->replay_gain_filter,
 					    chunk->replay_gain_serial != 0
 					    ? &chunk->replay_gain_info