soundwire: intel: implement get_sdw_stream() operations

This is needed to retrieve the information when the stream is
allocated at the dai_link level.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200630184356.24939-2-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/soundwire/intel.c

@@ -883,6 +883,22 @@ static int intel_pdm_set_sdw_stream(struct snd_soc_dai *dai,
 	return cdns_set_sdw_stream(dai, stream, false, direction);
 }
 
+static void *intel_get_sdw_stream(struct snd_soc_dai *dai,
+				  int direction)
+{
+	struct sdw_cdns_dma_data *dma;
+
+	if (direction == SNDRV_PCM_STREAM_PLAYBACK)
+		dma = dai->playback_dma_data;
+	else
+		dma = dai->capture_dma_data;
+
+	if (!dma)
+		return NULL;
+
+	return dma->stream;
+}
+
 static const struct snd_soc_dai_ops intel_pcm_dai_ops = {
 	.startup = intel_startup,
 	.hw_params = intel_hw_params,
@@ -891,6 +907,7 @@ static const struct snd_soc_dai_ops intel_pcm_dai_ops = {
 	.hw_free = intel_hw_free,
 	.shutdown = intel_shutdown,
 	.set_sdw_stream = intel_pcm_set_sdw_stream,
+	.get_sdw_stream = intel_get_sdw_stream,
 };
 
 static const struct snd_soc_dai_ops intel_pdm_dai_ops = {
@@ -901,6 +918,7 @@ static const struct snd_soc_dai_ops intel_pdm_dai_ops = {
 	.hw_free = intel_hw_free,
 	.shutdown = intel_shutdown,
 	.set_sdw_stream = intel_pdm_set_sdw_stream,
+	.get_sdw_stream = intel_get_sdw_stream,
 };
 
 static const struct snd_soc_component_driver dai_component = {