Fix handling of the mixer-module adapter combo on IPC3 platforms

src/audio/mixer/mixer.c

@@ -82,11 +82,12 @@ static int mixer_process(struct processing_module *mod,
 	struct mixer_data *md = module_get_private_data(mod);
 	struct comp_dev *dev = mod->dev;
 	const struct audio_stream __sparse_cache *sources_stream[PLATFORM_MAX_STREAMS];
-	int32_t i = 0;
+	int32_t i = 0, j = 0;
 	uint32_t frames = INT32_MAX;
 	/* Redundant, but helps the compiler */
 	uint32_t source_bytes = 0;
 	uint32_t sink_bytes;
+	int active_input_buffers = 0;
 
 	comp_dbg(dev, "mixer_process() %d", num_input_buffers);
 
@@ -105,10 +106,11 @@ static int mixer_process(struct processing_module *mod,
 		if (avail_frames == 0)
 			continue;
 
+		active_input_buffers++;
 		frames = MIN(frames, avail_frames);
 	}
 
-	if (!num_input_buffers || (frames == 0 && md->sources_inactive)) {
+	if (!active_input_buffers) {
 		/*
 		 * Generate silence when sources are inactive. When
 		 * sources change to active, additionally keep
@@ -119,33 +121,37 @@ static int mixer_process(struct processing_module *mod,
 		if (!audio_stream_set_zero(mod->output_buffers[0].data, sink_bytes))
 			mod->output_buffers[0].size = sink_bytes;
 
-		md->sources_inactive = true;
-
 		return 0;
 	}
 
 	/* Every source has the same format, so calculate bytes based on the first one */
 	source_bytes = frames * audio_stream_frame_bytes(mod->input_buffers[0].data);
 
-	if (md->sources_inactive) {
-		md->sources_inactive = false;
-		comp_dbg(dev, "mixer_copy exit sources_inactive state");
-	}
-
 	sink_bytes = frames * audio_stream_frame_bytes(mod->output_buffers[0].data);
 
 	comp_dbg(dev, "mixer_process(), source_bytes = 0x%x, sink_bytes = 0x%x",
 		 source_bytes, sink_bytes);
 
 	/* mix streams */
-	for (i = 0; i < num_input_buffers; i++)
-		sources_stream[i] = mod->input_buffers[i].data;
+	for (i = 0; i < num_input_buffers; i++) {
+		uint32_t avail_frames;
+
+		avail_frames = audio_stream_avail_frames_aligned(mod->input_buffers[i].data,
+								 mod->output_buffers[0].data);
+
+		/* if one source is inactive, skip it */
+		if (avail_frames == 0)
+			continue;
+
+		sources_stream[j++] = mod->input_buffers[i].data;
+	}
 
-	md->mix_func(dev, mod->output_buffers[0].data, sources_stream, num_input_buffers, frames);
+	if (j)
+		md->mix_func(dev, mod->output_buffers[0].data, sources_stream, j, frames);
 	mod->output_buffers[0].size = sink_bytes;
 
 	/* update source buffer consumed bytes */
-	for (i = 0; i < num_input_buffers; i++)
+	for (i = 0; i < j; i++)
 		mod->input_buffers[i].consumed = source_bytes;
 
 	return 0;

src/audio/module_adapter/module_adapter.c

@@ -167,21 +167,16 @@ int module_adapter_prepare(struct comp_dev *dev)
 
 	comp_dbg(dev, "module_adapter_prepare() start");
 
-	/*
-	 * check if the component is already active. This could happen in the case of mixer when
-	 * one of the sources is already active
-	 */
-	if (dev->state == COMP_STATE_ACTIVE)
-		return 0;
+	/* Prepare module */
+	ret = module_prepare(mod);
+	if (ret) {
+		if (ret == PPL_STATUS_PATH_STOP)
+			return ret;
 
-	/* Are we already prepared? */
-	ret = comp_set_state(dev, COMP_TRIGGER_PREPARE);
-	if (ret < 0)
-		return ret;
+		comp_err(dev, "module_adapter_prepare() error %x: module prepare failed",
+			 ret);
 
-	if (ret == COMP_STATUS_STATE_ALREADY_SET) {
-		comp_warn(dev, "module_adapter_prepare(): module has already been prepared");
-		return PPL_STATUS_PATH_STOP;
+		return -EIO;
 	}
 
 	/* Get period_bytes first on prepare(). At this point it is guaranteed that the stream
@@ -195,16 +190,21 @@ int module_adapter_prepare(struct comp_dev *dev)
 
 	buffer_release(sink_c);
 
-	/* Prepare module */
-	ret = module_prepare(mod);
-	if (ret) {
-		if (ret == PPL_STATUS_PATH_STOP)
-			return ret;
+	/*
+	 * check if the component is already active. This could happen in the case of mixer when
+	 * one of the sources is already active
+	 */
+	if (dev->state == COMP_STATE_ACTIVE)
+		return PPL_STATUS_PATH_STOP;
 
-		comp_err(dev, "module_adapter_prepare() error %x: module prepare failed",
-			 ret);
+	/* Are we already prepared? */
+	ret = comp_set_state(dev, COMP_TRIGGER_PREPARE);
+	if (ret < 0)
+		return ret;
 
-		return -EIO;
+	if (ret == COMP_STATUS_STATE_ALREADY_SET) {
+		comp_warn(dev, "module_adapter_prepare(): module has already been prepared");
+		return PPL_STATUS_PATH_STOP;
 	}
 
 	mod->deep_buff_bytes = 0;

src/include/sof/audio/mixer.h

@@ -32,8 +32,6 @@ void sys_comp_module_mixer_interface_init(void);
 
 /* mixer component private data */
 struct mixer_data {
-	bool sources_inactive;
-
 	void (*mix_func)(struct comp_dev *dev, struct audio_stream __sparse_cache *sink,
 			 const struct audio_stream __sparse_cache **sources, uint32_t count,
 			 uint32_t frames);