ASoC: SOF: ipc4-pcm: Handle COMPR DRAIN triggers as EOS pipeline state

The DRAIN trigger is received by a compr device when user space wrote all
the data to the buffer and it is waiting for the decoding to be completed.

Set the pipeline state to EOS in firmware so it can expect the stream to
be stopping anytime soon.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>

Author: ujfalusi

sound/soc/sof/ipc4-pcm.c

@@ -153,7 +153,8 @@ sof_ipc4_add_pipeline_to_trigger_list(struct snd_sof_dev *sdev, int state,
 	struct snd_sof_widget *pipe_widget = spipe->pipe_widget;
 	struct sof_ipc4_pipeline *pipeline = pipe_widget->private;
 
-	if (pipeline->skip_during_fe_trigger && state != SOF_IPC4_PIPE_RESET)
+	if (pipeline->skip_during_fe_trigger && state != SOF_IPC4_PIPE_RESET &&
+	    state != SOF_IPC4_PIPE_EOS)
 		return;
 
 	switch (state) {
@@ -173,7 +174,12 @@ sof_ipc4_add_pipeline_to_trigger_list(struct snd_sof_dev *sdev, int state,
 							  true);
 		break;
 	case SOF_IPC4_PIPE_PAUSED:
-		/* Pause the pipeline only when its started_count is 1 more than paused_count */
+	case SOF_IPC4_PIPE_EOS:
+		/*
+		 * Pause the pipeline only when its started_count is 1 more than
+		 * paused_count.
+		 * Same rule applies to EOS state.
+		 */
 		if (spipe->paused_count == (spipe->started_count - 1))
 			sof_ipc4_add_pipeline_by_priority(trigger_list, pipe_widget, pipe_priority,
 							  true);
@@ -499,8 +505,9 @@ static int sof_ipc4_trigger_pipelines(struct snd_soc_component *component,
 		goto free;
 	}
 
-	/* no need to pause before reset or before pause release */
-	if (state == SOF_IPC4_PIPE_RESET || cmd == SNDRV_PCM_TRIGGER_PAUSE_RELEASE)
+	/* no need to pause before reset, EOS or before pause release */
+	if (state == SOF_IPC4_PIPE_RESET || state == SOF_IPC4_PIPE_EOS ||
+	    cmd == SNDRV_PCM_TRIGGER_PAUSE_RELEASE)
 		goto skip_pause_transition;
 
 	/*
@@ -602,6 +609,10 @@ static int sof_ipc4_pcm_trigger(struct snd_soc_component *component,
 	case SNDRV_PCM_TRIGGER_STOP:
 		state = SOF_IPC4_PIPE_PAUSED;
 		break;
+	case SND_COMPR_TRIGGER_DRAIN:
+	case SND_COMPR_TRIGGER_PARTIAL_DRAIN:
+		state = SOF_IPC4_PIPE_EOS;
+		break;
 	default:
 		dev_err(component->dev, "%s: unhandled trigger cmd %d\n", __func__, cmd);
 		return -EINVAL;