[PATCH v2 05/15] dmaengine: omap-dma: Add support for no_wakeup in cyclic mode
Peter Ujfalusi
peter.ujfalusi at ti.com
Thu Sep 13 09:37:55 EDT 2012
When requested 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 | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index c6a711d..cbe087e 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -374,6 +374,7 @@ static struct dma_async_tx_descriptor *omap_dma_prep_dma_cyclic(
struct omap_desc *d;
dma_addr_t dev_addr;
unsigned es, sync_type;
+ unsigned long tx_flags = 0;
u32 burst;
if (dir == DMA_DEV_TO_MEM) {
@@ -429,7 +430,11 @@ 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 (!no_wakeup) {
+ omap_enable_dma_irq(c->dma_ch, OMAP_DMA_FRAME_IRQ);
+ tx_flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
+ }
omap_disable_dma_irq(c->dma_ch, OMAP_DMA_BLOCK_IRQ);
}
@@ -438,7 +443,7 @@ 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, tx_flags);
}
static int omap_dma_slave_config(struct omap_chan *c, struct dma_slave_config *cfg)
--
1.7.12
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