From: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>

This is required to reset the DMA read/write pointers when the stream is
prepared and restarted after a call to snd_pcm_drain()/snd_pcm_drop().
Also, now that the stream is reset during stop, do not save LLP registers
in the case of STOP/suspend to avoid erroneous delay reporting.

Link: https://github.com/thesofproject/sof/issues/9502
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
---
 sound/soc/sof/intel/hda-dai-ops.c | 23 ++++++++++-------------
 sound/soc/sof/intel/hda-dai.c     |  1 +
 2 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/sound/soc/sof/intel/hda-dai-ops.c b/sound/soc/sof/intel/hda-dai-ops.c
index 484c76147885..92681ca7f24d 100644
--- a/sound/soc/sof/intel/hda-dai-ops.c
+++ b/sound/soc/sof/intel/hda-dai-ops.c
@@ -346,20 +346,21 @@ static int hda_trigger(struct snd_sof_dev *sdev, struct snd_soc_dai *cpu_dai,
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 		snd_hdac_ext_stream_start(hext_stream);
 		break;
-	case SNDRV_PCM_TRIGGER_SUSPEND:
-	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
-		snd_hdac_ext_stream_clear(hext_stream);
-
 		/*
-		 * Save the LLP registers in case the stream is
-		 * restarting due PAUSE_RELEASE, or START without a pcm
-		 * close/open since in this case the LLP register is not reset
-		 * to 0 and the delay calculation will return with invalid
-		 * results.
+		 * Save the LLP registers since in case of PAUSE the LLP
+		 * register are not reset to 0, the delay calculation will use
+		 * the saved offsets for compensating the delay calculation.
 		 */
 		hext_stream->pplcllpl = readl(hext_stream->pplc_addr + AZX_REG_PPLCLLPL);
 		hext_stream->pplcllpu = readl(hext_stream->pplc_addr + AZX_REG_PPLCLLPU);
+		snd_hdac_ext_stream_clear(hext_stream);
+		break;
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_STOP:
+		hext_stream->pplcllpl = 0;
+		hext_stream->pplcllpu = 0;
+		snd_hdac_ext_stream_clear(hext_stream);
 		break;
 	default:
 		dev_err(sdev->dev, "unknown trigger command %d\n", cmd);
@@ -512,7 +513,6 @@ static const struct hda_dai_widget_dma_ops sdw_ipc4_chain_dma_ops = {
 static int hda_ipc3_post_trigger(struct snd_sof_dev *sdev, struct snd_soc_dai *cpu_dai,
 				 struct snd_pcm_substream *substream, int cmd)
 {
-	struct hdac_ext_stream *hext_stream = hda_get_hext_stream(sdev, cpu_dai, substream);
 	struct snd_soc_dapm_widget *w = snd_soc_dai_get_widget(cpu_dai, substream->stream);
 
 	switch (cmd) {
@@ -527,9 +527,6 @@ static int hda_ipc3_post_trigger(struct snd_sof_dev *sdev, struct snd_soc_dai *c
 		if (ret < 0)
 			return ret;
 
-		if (cmd == SNDRV_PCM_TRIGGER_STOP)
-			return hda_link_dma_cleanup(substream, hext_stream, cpu_dai);
-
 		break;
 	}
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
diff --git a/sound/soc/sof/intel/hda-dai.c b/sound/soc/sof/intel/hda-dai.c
index 8cccf38967e7..ac505c7ad342 100644
--- a/sound/soc/sof/intel/hda-dai.c
+++ b/sound/soc/sof/intel/hda-dai.c
@@ -302,6 +302,7 @@ static int __maybe_unused hda_dai_trigger(struct snd_pcm_substream *substream, i
 	}
 
 	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 		ret = hda_link_dma_cleanup(substream, hext_stream, dai);
 		if (ret < 0) {
-- 
2.43.0