Subject: [PATCH 1/2] dmaengine: Add flags parameter to dmaengine_prep_dma_cyclic()

From: Peter Ujfalusi <[email-masked]>
Date: Mon, 24 Sep 2012 10:58:04 +0300

With this parameter added to dmaengine_prep_dma_cyclic() the API will be in
sync with other dmaengine_prep_*() functions.
The dmaengine_prep_dma_cyclic() function primarily used by audio for cyclic
transfer required by ALSA, we use the from audio to ask dma drivers to
suppress interrupts (if DMA_PREP_INTERRUPT is cleared) when it is supported
on the platform.

Signed-off-by: Peter Ujfalusi <[email-masked]>
CC: Lars-Peter Clausen <[email-masked]>
---
 include/linux/dmaengine.h     | 3 ++-
 sound/soc/soc-dmaengine-pcm.c | 6 +++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 09da4e5..d3201e4 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -653,7 +653,8 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_rio_sg(
 
 static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
 		struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
-		size_t period_len, enum dma_transfer_direction dir)
+		size_t period_len, enum dma_transfer_direction dir,
+		unsigned long flags)
 {
 	return chan->device->device_prep_dma_cyclic(chan, buf_addr, buf_len,
 						period_len, dir, flags, NULL);
diff --git a/sound/soc/soc-dmaengine-pcm.c b/sound/soc/soc-dmaengine-pcm.c
index 5df529e..bbc1257 100644
--- a/sound/soc/soc-dmaengine-pcm.c
+++ b/sound/soc/soc-dmaengine-pcm.c
@@ -140,14 +140,18 @@ static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)
 	struct dma_chan *chan = prtd->dma_chan;
 	struct dma_async_tx_descriptor *desc;
 	enum dma_transfer_direction direction;
+	unsigned long flags = DMA_CTRL_ACK;
 
 	direction = snd_pcm_substream_to_dma_direction(substream);
 
+	if (!substream->runtime->no_period_wakeup)
+		flags |= DMA_PREP_INTERRUPT;
+
 	prtd->pos = 0;
 	desc = dmaengine_prep_dma_cyclic(chan,
 		substream->runtime->dma_addr,
 		snd_pcm_lib_buffer_bytes(substream),
-		snd_pcm_lib_period_bytes(substream), direction);
+		snd_pcm_lib_period_bytes(substream), direction, flags);
 
 	if (!desc)
 		return -ENOMEM;
-- 
1.7.12