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Subject[PATCH 2/3] dmaenegine: edma: allow pause/resume for non-cyclic mode
Date
The 8250_omap serial driver relies on dmaengine_pause() actually
pausing the DMA transfer. Before this patch dmaengine_pause() is
a NOP for non-cylic DMA transfers. This allowed the 8250_omap
driver to read DMA buffers while the DMA was still active,
resulting in lost serial data.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
---
drivers/dma/edma.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
index bf09db7..88853af 100644
--- a/drivers/dma/edma.c
+++ b/drivers/dma/edma.c
@@ -300,8 +300,7 @@ static int edma_dma_pause(struct dma_chan *chan)
{
struct edma_chan *echan = to_edma_chan(chan);

- /* Pause/Resume only allowed with cyclic mode */
- if (!echan->edesc || !echan->edesc->cyclic)
+ if (!echan->edesc)
return -EINVAL;

edma_pause(echan->ch_num);
@@ -312,10 +311,6 @@ static int edma_dma_resume(struct dma_chan *chan)
{
struct edma_chan *echan = to_edma_chan(chan);

- /* Pause/Resume only allowed with cyclic mode */
- if (!echan->edesc->cyclic)
- return -EINVAL;
-
edma_resume(echan->ch_num);
return 0;
}
--
1.7.10.4

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