When working with non-coherent transfer buffers, we have to sync
device and cpu for outgoing and incoming buffers. Fix the driver where
non-coherent buffers are used in device context.
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>