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

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>

diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
index bf09db7ca9ee9c691bcb59888575d2679b4ddd3e..88853af6948967defce011b65fa88b4ae2ace5d6 100644 (file)
--- 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;
 }