[PATCH 4/4] dma: imx-sdma: start transfer in issue_pending

Sascha Hauer s.hauer at pengutronix.de
Mon Jan 9 04:32:50 EST 2012


The DMA API requires that transfers are started in issue_pending
instead of tx_submit. Fix this.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 drivers/dma/imx-sdma.c |   11 +++++------
 1 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index f993955..eb28bb0 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -833,15 +833,12 @@ static struct sdma_channel *to_sdma_chan(struct dma_chan *chan)
 static dma_cookie_t sdma_tx_submit(struct dma_async_tx_descriptor *tx)
 {
 	struct sdma_channel *sdmac = to_sdma_chan(tx->chan);
-	struct sdma_engine *sdma = sdmac->sdma;
 	dma_cookie_t cookie;
 
 	spin_lock_irq(&sdmac->lock);
 
 	cookie = sdma_assign_cookie(sdmac);
 
-	sdma_enable_channel(sdma, sdmac->channel);
-
 	spin_unlock_irq(&sdmac->lock);
 
 	return cookie;
@@ -1126,9 +1123,11 @@ static enum dma_status sdma_tx_status(struct dma_chan *chan,
 
 static void sdma_issue_pending(struct dma_chan *chan)
 {
-	/*
-	 * Nothing to do. We only have a single descriptor
-	 */
+	struct sdma_channel *sdmac = to_sdma_chan(chan);
+	struct sdma_engine *sdma = sdmac->sdma;
+
+	if (sdmac->status == DMA_IN_PROGRESS)
+		sdma_enable_channel(sdma, sdmac->channel);
 }
 
 #define SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V1	34
-- 
1.7.7.3




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