[alsa-devel] [PATCH v3 05/15] dmaengine: omap-dma: Add support to suppress interrupts in cyclic mode

[Peter Ujfalusi]

When requested (DMA_PREP_INTERRUPT is cleared in flags) disable all DMA
interrupts for the channel. In this mode user space does not expect
periodic reports from kernel about the progress of the audio stream.
PulseAudio for example support this type of mode.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi at ti.com>
CC: Russell King <rmk+kernel at arm.linux.org.uk>
---
 drivers/dma/omap-dma.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index 4d2650f..f59f244 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -429,7 +429,10 @@ static struct dma_async_tx_descriptor *omap_dma_prep_dma_cyclic(
 	if (!c->cyclic) {
 		c->cyclic = true;
 		omap_dma_link_lch(c->dma_ch, c->dma_ch);
-		omap_enable_dma_irq(c->dma_ch, OMAP_DMA_FRAME_IRQ);
+
+		if (flags & DMA_PREP_INTERRUPT)
+			omap_enable_dma_irq(c->dma_ch, OMAP_DMA_FRAME_IRQ);
+
 		omap_disable_dma_irq(c->dma_ch, OMAP_DMA_BLOCK_IRQ);
 	}
 
@@ -438,7 +441,7 @@ static struct dma_async_tx_descriptor *omap_dma_prep_dma_cyclic(
 		omap_set_dma_dest_burst_mode(c->dma_ch, OMAP_DMA_DATA_BURST_16);
 	}
 
-	return vchan_tx_prep(&c->vc, &d->vd, DMA_CTRL_ACK | DMA_PREP_INTERRUPT);
+	return vchan_tx_prep(&c->vc, &d->vd, flags);
 }
 
 static int omap_dma_slave_config(struct omap_chan *c, struct dma_slave_config *cfg)
-- 
1.7.12