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dmaenegine: edma: allow pause/resume for non-cyclic mode

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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>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
John Ogness 2015-04-27 13:52:25 +02:00 committed by Greg Kroah-Hartman
parent c2d4bb9d93
commit 02ec6041a8
1 changed files with 1 additions and 6 deletions
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7
drivers/dma/edma.c
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@ -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;
}