carma-fpga: pass correct flags to ->device_prep_dma_memcpy()

DMA unmapping is handled by a driver so tell fsldma.c driver
(which is the DMA engine driver used by carma-fpga) to skip
unmapping destination and source buffers.

Cc: Ira W. Snyder <iws@ovro.caltech.edu>
Cc: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Dan Williams <djbw@fb.com>

drivers/misc/carma/carma-fpga.c

@@ -631,6 +631,8 @@ static int data_submit_dma(struct fpga_device *priv, struct data_buf *buf)
 	struct dma_async_tx_descriptor *tx;
 	dma_cookie_t cookie;
 	dma_addr_t dst, src;
+	unsigned long dma_flags = DMA_COMPL_SKIP_DEST_UNMAP |
+				  DMA_COMPL_SKIP_SRC_UNMAP;
 
 	dst_sg = buf->vb.sglist;
 	dst_nents = buf->vb.sglen;
@@ -666,7 +668,7 @@ static int data_submit_dma(struct fpga_device *priv, struct data_buf *buf)
 	src = SYS_FPGA_BLOCK;
 	tx = chan->device->device_prep_dma_memcpy(chan, dst, src,
 						  REG_BLOCK_SIZE,
-						  0);
+						  dma_flags);
 	if (!tx) {
 		dev_err(priv->dev, "unable to prep SYS-FPGA DMA\n");
 		return -ENOMEM;