ASoC: omap-pcm: Fix the no period wakeup implementation

After omap_request_dma the BLOCK_IRQ is enabled as default
configuration for the channel.
If we are requested for no period wakeup, we need to disable
the BLOCK_IRQ in order to not receive any interrupts.
Signed-off-by: NPeter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: NJarkko Nikula <jarkko.nikula@bitmer.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/omap/omap-pcm.c

@@ -198,6 +198,14 @@ static int omap_pcm_prepare(struct snd_pcm_substream *substream)
 			      OMAP_DMA_LAST_IRQ | OMAP_DMA_BLOCK_IRQ);
 	else if (!substream->runtime->no_period_wakeup)
 		omap_enable_dma_irq(prtd->dma_ch, OMAP_DMA_FRAME_IRQ);
+	else {
+		/*
+		 * No period wakeup:
+		 * we need to disable BLOCK_IRQ, which is enabled by the omap
+		 * dma core at request dma time.
+		 */
+		omap_disable_dma_irq(prtd->dma_ch, OMAP_DMA_BLOCK_IRQ);
+	}
 
 	if (!(cpu_class_is_omap1())) {
 		omap_set_dma_src_burst_mode(prtd->dma_ch,