spi: dw-mid: follow new DMAengine workflow

Though intel-mid-dma does not follow a new DMA workflow (*) let's prepare SPI
DW driver for that.

(*) The client is obliged to call dma_async_issue_pending() which starts the
actual transfers. Old DMA drivers do not follow this, since requirement was
introduced in the discussion of [1].

[1] http://www.spinics.net/lists/arm-kernel/msg125987.html

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c
index a507add6231e..46c6d58e1fda 100644
--- a/drivers/spi/spi-dw-mid.c
+++ b/drivers/spi/spi-dw-mid.c
@@ -150,7 +150,7 @@ static int mid_spi_dma_transfer(struct dw_spi *dws, int cs_change)
                                 &dws->tx_sgl,
                                 1,
                                 DMA_MEM_TO_DEV,
-                                DMA_PREP_INTERRUPT);
+                                DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
         txdesc->callback = dw_spi_dma_done;
         txdesc->callback_param = dws;
 
@@ -172,13 +172,17 @@ static int mid_spi_dma_transfer(struct dw_spi *dws, int cs_change)
                                 &dws->rx_sgl,
                                 1,
                                 DMA_DEV_TO_MEM,
-                                DMA_PREP_INTERRUPT);
+                                DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
         rxdesc->callback = dw_spi_dma_done;
         rxdesc->callback_param = dws;
 
         /* rx must be started before tx due to spi instinct */
         dmaengine_submit(rxdesc);
+        dma_async_issue_pending(dws->rxchan);
+
         dmaengine_submit(txdesc);
+        dma_async_issue_pending(dws->txchan);
+
         return 0;
 }