ASoC: soc-pcm: add a flag to reverse the stop sequence

On stream stop, currently CPU DAI stop sequence invoked first
followed by DMA. For Few platforms, it is required to stop the
DMA first before stopping CPU DAI.

Introduced new flag in dai_link structure for reordering stop sequence.
Based on flag check, ASoC core will re-order the stop sequence.

Fixes: 4378f1fb ("ASoC: soc-pcm: Use different sequence for start/stop trigger")
Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Link: https://lore.kernel.org/r/20210716123015.15697-1-vijendar.mukunda@amd.comSigned-off-by: Mark Brown <broonie@kernel.org>

include/sound/soc.h

@@ -712,6 +712,12 @@ struct snd_soc_dai_link {
 	/* Do not create a PCM for this DAI link (Backend link) */
 	unsigned int ignore:1;
 
+	/* This flag will reorder stop sequence. By enabling this flag
+	 * DMA controller stop sequence will be invoked first followed by
+	 * CPU DAI driver stop sequence
+	 */
+	unsigned int stop_dma_first:1;
+
 #ifdef CONFIG_SND_SOC_TOPOLOGY
 	struct snd_soc_dobj dobj; /* For topology */
 #endif

sound/soc/soc-pcm.c

@@ -1015,6 +1015,7 @@ static int soc_pcm_hw_params(struct snd_pcm_substream *substream,
 
 static int soc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 {
+	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 	int ret = -EINVAL, _ret = 0;
 	int rollback = 0;
 
@@ -1055,6 +1056,15 @@ static int soc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		if (rtd->dai_link->stop_dma_first) {
+			ret = snd_soc_pcm_component_trigger(substream, cmd, rollback);
+			if (ret < 0)
+				break;
+
+			ret = snd_soc_pcm_dai_trigger(substream, cmd, rollback);
+			if (ret < 0)
+				break;
+		} else {
 			ret = snd_soc_pcm_dai_trigger(substream, cmd, rollback);
 			if (ret < 0)
 				break;
@@ -1062,7 +1072,7 @@ static int soc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 			ret = snd_soc_pcm_component_trigger(substream, cmd, rollback);
 			if (ret < 0)
 				break;
-
+		}
 		ret = snd_soc_link_trigger(substream, cmd, rollback);
 		break;
 	}