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 <peter.ujfalusi@ti.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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 <peter.ujfalusi@ti.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Merge branch 'fixes' of git://git.infradead.org/users/vkoul/slave-dma

Pull slave-dmaengine fixes from Vinod Koul:
 "Two small fixes for omap dmaengine driver which fixes cyclic suspend
  and resume"

* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: omap-dma: Restore the CLINK_CTRL in resume path
  dmaengine: omap-dma: Add memory barrier to dma_resume path