dmaengine: sun6i: Set default maxburst size and bus width

Some DMA clients, as audio, don't set the maxburst size and bus width
on the memory side when starting DMA transfers.
This patch prevents such transfers to be aborted by providing system
default values to the lacking ones.

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c
index b08245e..cd436c6 100644
--- a/drivers/dma/sun6i-dma.c
+++ b/drivers/dma/sun6i-dma.c
@@ -470,10 +470,30 @@
 {
 	s8 src_width, dst_width, src_burst, dst_burst;
 
-	src_burst = convert_burst(sconfig->src_maxburst);
-	src_width = convert_buswidth(sconfig->src_addr_width);
-	dst_burst = convert_burst(sconfig->dst_maxburst);
-	dst_width = convert_buswidth(sconfig->dst_addr_width);
+	switch (direction) {
+	case DMA_MEM_TO_DEV:
+		src_burst = convert_burst(sconfig->src_maxburst ?
+					sconfig->src_maxburst : 8);
+		src_width = convert_buswidth(sconfig->src_addr_width !=
+						DMA_SLAVE_BUSWIDTH_UNDEFINED ?
+				sconfig->src_addr_width :
+				DMA_SLAVE_BUSWIDTH_4_BYTES);
+		dst_burst = convert_burst(sconfig->dst_maxburst);
+		dst_width = convert_buswidth(sconfig->dst_addr_width);
+		break;
+	case DMA_DEV_TO_MEM:
+		src_burst = convert_burst(sconfig->src_maxburst);
+		src_width = convert_buswidth(sconfig->src_addr_width);
+		dst_burst = convert_burst(sconfig->dst_maxburst ?
+					sconfig->dst_maxburst : 8);
+		dst_width = convert_buswidth(sconfig->dst_addr_width !=
+						DMA_SLAVE_BUSWIDTH_UNDEFINED ?
+				sconfig->dst_addr_width :
+				DMA_SLAVE_BUSWIDTH_4_BYTES);
+		break;
+	default:
+		return -EINVAL;
+	}
 
 	if (src_burst < 0)
 		return src_burst;