[PATCH] mmc: dw_mmc: Reset DMA before enabling IDMAC

Acked-by: Jaehoon Chung <jh80.chung@samsung.com>

On 10/07/2014 03:11 AM, Doug Anderson wrote:

Sonny,

On Mon, Oct 6, 2014 at 10:53 AM, Sonny Rao [off-list ref] wrote:

quoted

We've already got a reset of DMA after it's done.  Add one before we
start DMA too.  This fixes a data corruption on Rockchip SoCs which
will get bad data when doing a DMA transfer after doing a PIO transfer.

We tested this on an Exynos 5800 with HS200 and didn't notice any
difference in sequential read throughput.

Signed-off-by: Sonny Rao <redacted>
Signed-off-by: Doug Anderson <dianders@chromium.org>
---
 drivers/mmc/host/dw_mmc.c | 4 ++++
 1 file changed, 4 insertions(+)

Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>