From b3d09da7e1771decc6833d1fa662bf994948c8e6 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Tue, 16 Sep 2014 22:45:56 +0300 Subject: dmaengine: omap-dma: Add memory barrier to dma_resume path Add mb() call to resume path to ensure the necessary barrier. Resume can happen after waking up from suspend for example. Signed-off-by: Peter Ujfalusi Acked-by: Russell King Signed-off-by: Vinod Koul diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c index 4cf7d9a..c01ea50 100644 --- a/drivers/dma/omap-dma.c +++ b/drivers/dma/omap-dma.c @@ -1017,6 +1017,8 @@ static int omap_dma_resume(struct omap_chan *c) return -EINVAL; if (c->paused) { + mb(); + omap_dma_start(c, c->desc); c->paused = false; } -- cgit v0.10.2 From bfb607451786829430ecdd5bcd51c5dac03e3639 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Tue, 16 Sep 2014 22:45:57 +0300 Subject: dmaengine: omap-dma: Restore the CLINK_CTRL in resume path When the audio stream is paused or suspended we stop the sDMA and when it is unpaused/resumed we start the channel without reconfiguring it. The omap_dma_stop() clears the link configuration when we pause the dma, but it is not setting it back on start. This will result only one audio buffer to be played back and the DMA will stop, since the linking is disabled. We need to restore the CLINK_CTRL register in case of resume. Signed-off-by: Peter Ujfalusi Acked-by: Russell King Signed-off-by: Vinod Koul diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c index c01ea50..bbea824 100644 --- a/drivers/dma/omap-dma.c +++ b/drivers/dma/omap-dma.c @@ -1019,6 +1019,9 @@ static int omap_dma_resume(struct omap_chan *c) if (c->paused) { mb(); + /* Restore channel link register */ + omap_dma_chan_write(c, CLNK_CTRL, c->desc->clnk_ctrl); + omap_dma_start(c, c->desc); c->paused = false; } -- cgit v0.10.2