pipeline: handle failed latency calculation

copier_comp_trigger() calls pipeline_get_dai_comp_latency() for
playback pipelines to obtain the pipeline DAI copier, if there is
one, and to calculate the pipeline latency. The latency is
calculated using the .get_total_data_processed() component
operation, but that operation is only available for DAI, host and
copier components. SOF pipelines often have other components at one
of the pipeline ends, so the latency calculation fails. However, that
shouldn't prevent pipeline_get_dai_comp_latency() from finding the
DAI component.
This fixes the notorious "failed to find dai comp or sink pipeline
not running." error message.

Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>

Author: lyakh

src/audio/copier/copier.c

@@ -551,6 +551,7 @@ static int create_ipcgtw(struct comp_dev *parent_dev, struct copier_data *cd,
 }
 #endif
 
+/* Playback only */
 static int init_pipeline_reg(struct comp_dev *dev)
 {
 	struct copier_data *cd = comp_get_drvdata(dev);
@@ -985,6 +986,7 @@ static int copier_comp_trigger(struct comp_dev *dev, int cmd)
 		}
 	}
 
+	/* For capture cd->pipeline_reg_offset == 0 */
 	if (ret < 0 || !cd->endpoint_num || !cd->pipeline_reg_offset)
 		return ret;
 

src/audio/pipeline/pipeline-graph.c

@@ -486,7 +486,7 @@ struct comp_dev *pipeline_get_dai_comp(uint32_t pipeline_id, int dir)
 }
 
 #if CONFIG_IPC_MAJOR_4
-/* visit connected pipeline to find the dai comp and latency.
+/* Playback only: visit connected pipeline to find the dai comp and latency.
  * This function walks down through a pipelines chain looking for the target dai component.
  * Calculates the delay of each pipeline by determining the number of buffered blocks.
  */
@@ -521,8 +521,6 @@ struct comp_dev *pipeline_get_dai_comp_latency(uint32_t pipeline_id, uint32_t *l
 		/* Calculate pipeline latency */
 		input_data = comp_get_total_data_processed(source, 0, true);
 		output_data = comp_get_total_data_processed(ipc_sink->cd, 0, false);
-		if (!input_data || !output_data)
-			return NULL;
 
 		ret = comp_get_attribute(source, COMP_ATTR_BASE_CONFIG, &input_base_cfg);
 		if (ret < 0)
@@ -532,19 +530,21 @@ struct comp_dev *pipeline_get_dai_comp_latency(uint32_t pipeline_id, uint32_t *l
 		if (ret < 0)
 			return NULL;
 
-		*latency += input_data / input_base_cfg.ibs - output_data / output_base_cfg.obs;
+		if (input_data && output_data)
+			*latency += input_data / input_base_cfg.ibs -
+				output_data / output_base_cfg.obs;
 
-		/* If the component doesn't have a sink buffer, this is a dai. */
+		/* If the component doesn't have a sink buffer, it can be a dai. */
 		if (list_is_empty(&ipc_sink->cd->bsink_list))
-			return ipc_sink->cd;
+			return dev_comp_type(ipc_sink->cd) == SOF_COMP_DAI ? ipc_sink->cd : NULL;
 
 		/* Get a component connected to our sink buffer - hop to a next pipeline */
 		buffer = buffer_from_list(comp_buffer_list(ipc_sink->cd, PPL_DIR_DOWNSTREAM)->next,
 					  PPL_DIR_DOWNSTREAM);
 		source = buffer_get_comp(buffer, PPL_DIR_DOWNSTREAM);
 
 		/* buffer_comp is in another pipeline and it is not complete */
-		if (!source->pipeline)
+		if (!source || !source->pipeline)
 			return NULL;
 
 		/* Get a next sink component */