spi: dw-mid: convert to use DMAengine wrappers

Instead of direct dereference to dmaengine callbacks we are going to use
DMAengine wrappers.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c
index 7bdf9374..a507add 100644
--- a/drivers/spi/spi-dw-mid.c
+++ b/drivers/spi/spi-dw-mid.c
@@ -113,8 +113,7 @@
 
 static int mid_spi_dma_transfer(struct dw_spi *dws, int cs_change)
 {
-	struct dma_async_tx_descriptor *txdesc = NULL, *rxdesc = NULL;
-	struct dma_chan *txchan, *rxchan;
+	struct dma_async_tx_descriptor *txdesc, *rxdesc;
 	struct dma_slave_config txconf, rxconf;
 	u16 dma_ctrl = 0;
 
@@ -132,8 +131,6 @@
 	}
 
 	dws->dma_chan_done = 0;
-	txchan = dws->txchan;
-	rxchan = dws->rxchan;
 
 	/* 2. Prepare the TX dma transfer */
 	txconf.direction = DMA_MEM_TO_DEV;
@@ -143,14 +140,13 @@
 	txconf.dst_addr_width = dws->dma_width;
 	txconf.device_fc = false;
 
-	txchan->device->device_control(txchan, DMA_SLAVE_CONFIG,
-				       (unsigned long) &txconf);
+	dmaengine_slave_config(dws->txchan, &txconf);
 
 	memset(&dws->tx_sgl, 0, sizeof(dws->tx_sgl));
 	dws->tx_sgl.dma_address = dws->tx_dma;
 	dws->tx_sgl.length = dws->len;
 
-	txdesc = dmaengine_prep_slave_sg(txchan,
+	txdesc = dmaengine_prep_slave_sg(dws->txchan,
 				&dws->tx_sgl,
 				1,
 				DMA_MEM_TO_DEV,
@@ -166,14 +162,13 @@
 	rxconf.src_addr_width = dws->dma_width;
 	rxconf.device_fc = false;
 
-	rxchan->device->device_control(rxchan, DMA_SLAVE_CONFIG,
-				       (unsigned long) &rxconf);
+	dmaengine_slave_config(dws->rxchan, &rxconf);
 
 	memset(&dws->rx_sgl, 0, sizeof(dws->rx_sgl));
 	dws->rx_sgl.dma_address = dws->rx_dma;
 	dws->rx_sgl.length = dws->len;
 
-	rxdesc = dmaengine_prep_slave_sg(rxchan,
+	rxdesc = dmaengine_prep_slave_sg(dws->rxchan,
 				&dws->rx_sgl,
 				1,
 				DMA_DEV_TO_MEM,
@@ -182,8 +177,8 @@
 	rxdesc->callback_param = dws;
 
 	/* rx must be started before tx due to spi instinct */
-	rxdesc->tx_submit(rxdesc);
-	txdesc->tx_submit(txdesc);
+	dmaengine_submit(rxdesc);
+	dmaengine_submit(txdesc);
 	return 0;
 }