ASoC: OMAP: Add checking to detect bufferless pcms

Add checking in hw_params and prepare to detect bufferless pcms(i.e. BT
<--> codec).
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/omap/omap-pcm.c

@@ -87,8 +87,10 @@ static int omap_pcm_hw_params(struct snd_pcm_substream *substream,
 	struct omap_pcm_dma_data *dma_data = rtd->dai->cpu_dai->dma_data;
 	int err = 0;
 
+	/* return if this is a bufferless transfer e.g.
+	 * codec <--> BT codec or GSM modem -- lg FIXME */
 	if (!dma_data)
-		return -ENODEV;
+		return 0;
 
 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 	runtime->dma_bytes = params_buffer_bytes(params);
@@ -134,6 +136,11 @@ static int omap_pcm_prepare(struct snd_pcm_substream *substream)
 	struct omap_pcm_dma_data *dma_data = prtd->dma_data;
 	struct omap_dma_channel_params dma_params;
 
+	/* return if this is a bufferless transfer e.g.
+	 * codec <--> BT codec or GSM modem -- lg FIXME */
+	if (!prtd->dma_data)
+		return 0;
+
 	memset(&dma_params, 0, sizeof(dma_params));
 	/*
 	 * Note: Regardless of interface data formats supported by OMAP McBSP