spi: dw-mid: convert value of dma_width to enum dma_slave_buswidth

DMAEngine has a specific type to be used for bus width. This patch converts the
code to use the values of the specific type when configure DMA transfer.

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 c8416ef..25c8fa7 100644
--- a/drivers/spi/spi-dw-mid.c
+++ b/drivers/spi/spi-dw-mid.c
@@ -100,6 +100,15 @@
 	dma_release_channel(dws->rxchan);
 }
 
+static enum dma_slave_buswidth convert_dma_width(u32 dma_width) {
+	if (dma_width == 1)
+		return DMA_SLAVE_BUSWIDTH_1_BYTE;
+	else if (dma_width == 2)
+		return DMA_SLAVE_BUSWIDTH_2_BYTES;
+
+	return DMA_SLAVE_BUSWIDTH_UNDEFINED;
+}
+
 /*
  * dws->dma_chan_busy is set before the dma transfer starts, callback for tx
  * channel will clear a corresponding bit.
@@ -126,7 +135,7 @@
 	txconf.dst_addr = dws->dma_addr;
 	txconf.dst_maxburst = LNW_DMA_MSIZE_16;
 	txconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
-	txconf.dst_addr_width = dws->dma_width;
+	txconf.dst_addr_width = convert_dma_width(dws->dma_width);
 	txconf.device_fc = false;
 
 	dmaengine_slave_config(dws->txchan, &txconf);
@@ -175,7 +184,7 @@
 	rxconf.src_addr = dws->dma_addr;
 	rxconf.src_maxburst = LNW_DMA_MSIZE_16;
 	rxconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
-	rxconf.src_addr_width = dws->dma_width;
+	rxconf.src_addr_width = convert_dma_width(dws->dma_width);
 	rxconf.device_fc = false;
 
 	dmaengine_slave_config(dws->rxchan, &rxconf);