Start the graph at trigger callback. Staring the graph at prepare does
not make sense as there is no data transfer at this point.
Moving this to trigger will also helps fix some of the issues seen with
pipewire and display port. This should also fix some of the Qualcomm DP codec
issues discussed at https://lkml.org/lkml/2025/5/29/102

CC: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
---
 sound/soc/qcom/qdsp6/q6apm-lpass-dais.c | 39 +++++++++++++++++--------
 1 file changed, 27 insertions(+), 12 deletions(-)

diff --git a/sound/soc/qcom/qdsp6/q6apm-lpass-dais.c b/sound/soc/qcom/qdsp6/q6apm-lpass-dais.c
index fc246485e326..21624a2803a6 100644
--- a/sound/soc/qcom/qdsp6/q6apm-lpass-dais.c
+++ b/sound/soc/qcom/qdsp6/q6apm-lpass-dais.c
@@ -159,6 +159,30 @@ static void q6apm_lpass_dai_shutdown(struct snd_pcm_substream *substream, struct
 	}
 }
 
+static int q6apm_lpass_dai_trigger(struct snd_pcm_substream *substream, int cmd, struct snd_soc_dai *dai)
+{
+	struct q6apm_lpass_dai_data *dai_data = dev_get_drvdata(dai->dev);
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		if (!dai_data->is_port_started[dai->id]) {
+			ret = q6apm_graph_start(dai_data->graph[dai->id]);
+			if (ret < 0)
+				dev_err(dai->dev, "Failed to start APM port %d\n", dai->id);
+			else
+				dai_data->is_port_started[dai->id] = true;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return ret;
+}
+
 static int q6apm_lpass_dai_prepare(struct snd_pcm_substream *substream, struct snd_soc_dai *dai)
 {
 	struct q6apm_lpass_dai_data *dai_data = dev_get_drvdata(dai->dev);
@@ -171,10 +195,6 @@ static int q6apm_lpass_dai_prepare(struct snd_pcm_substream *substream, struct s
 		q6apm_graph_stop(dai_data->graph[dai->id]);
 		dai_data->is_port_started[dai->id] = false;
 
-		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-			q6apm_graph_close(dai_data->graph[dai->id]);
-			dai_data->graph[dai->id] = NULL;
-		}
 	}
 
 	/**
@@ -203,14 +223,6 @@ static int q6apm_lpass_dai_prepare(struct snd_pcm_substream *substream, struct s
 		dev_err(dai->dev, "Failed to prepare Graph %d\n", rc);
 		goto err;
 	}
-
-	rc = q6apm_graph_start(dai_data->graph[dai->id]);
-	if (rc < 0) {
-		dev_err(dai->dev, "Failed to start APM port %d\n", dai->id);
-		goto err;
-	}
-	dai_data->is_port_started[dai->id] = true;
-
 	return 0;
 err:
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
@@ -254,6 +266,7 @@ static const struct snd_soc_dai_ops q6dma_ops = {
 	.shutdown	= q6apm_lpass_dai_shutdown,
 	.set_channel_map  = q6dma_set_channel_map,
 	.hw_params        = q6dma_hw_params,
+	.trigger	= q6apm_lpass_dai_trigger,
 };
 
 static const struct snd_soc_dai_ops q6i2s_ops = {
@@ -263,6 +276,7 @@ static const struct snd_soc_dai_ops q6i2s_ops = {
 	.set_channel_map  = q6dma_set_channel_map,
 	.hw_params        = q6dma_hw_params,
 	.set_fmt	= q6i2s_set_fmt,
+	.trigger	= q6apm_lpass_dai_trigger,
 };
 
 static const struct snd_soc_dai_ops q6hdmi_ops = {
@@ -271,6 +285,7 @@ static const struct snd_soc_dai_ops q6hdmi_ops = {
 	.shutdown	= q6apm_lpass_dai_shutdown,
 	.hw_params	= q6hdmi_hw_params,
 	.set_fmt	= q6i2s_set_fmt,
+	.trigger	= q6apm_lpass_dai_trigger,
 };
 
 static const struct snd_soc_component_driver q6apm_lpass_dai_component = {
-- 
2.47.3

On Thu, Feb 05, 2026 at 12:14:09PM -0500, Srinivas Kandagatla wrote:
> Start the graph at trigger callback. Staring the graph at prepare does
> not make sense as there is no data transfer at this point.
> Moving this to trigger will also helps fix some of the issues seen with
> pipewire and display port. This should also fix some of the Qualcomm DP codec
> issues discussed at https://lkml.org/lkml/2025/5/29/102

There is exactly one issue discussed there. Is it now fixed or not? If
it is, then you need a proper Fixes, Reported-by, Closes, etc. If it is
not, please drop it from the commit message.

> 
> CC: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
> ---
>  sound/soc/qcom/qdsp6/q6apm-lpass-dais.c | 39 +++++++++++++++++--------
>  1 file changed, 27 insertions(+), 12 deletions(-)
> 

-- 
With best wishes
Dmitry