From: Peter Ujfalusi <peter.ujfalusi@ti.com>
Date: Fri, 14 Sep 2012 12:05:48 +0000 (+0300)
Subject: dmaengine: omap-dma: Add support to suppress interrupts in cyclic mode
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=2dde5b909e117cc95a5e31604f9bfd043e78ad9d;p=openwrt%2Fstaging%2Fblogic.git

dmaengine: omap-dma: Add support to suppress interrupts in cyclic mode

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@ti.com>
Acked-by: Vinod Koul <vinod.koul@linux.intel.com>
Tested-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---

diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index 4d2650f4202c..f59f244f60fc 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)