DMA: PL08x: cleanup selection of buswidth

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 19 insertions, 15 deletions

diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index ba617e3f23f..2dd37ff753c 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -1105,13 +1105,26 @@ static u32 pl08x_cctl(u32 cctl)
         return cctl | PL080_CONTROL_PROT_SYS;
 }
 
+static u32 pl08x_width(enum dma_slave_buswidth width)
+{
+        switch (width) {
+        case DMA_SLAVE_BUSWIDTH_1_BYTE:
+                return PL080_WIDTH_8BIT;
+        case DMA_SLAVE_BUSWIDTH_2_BYTES:
+                return PL080_WIDTH_16BIT;
+        case DMA_SLAVE_BUSWIDTH_4_BYTES:
+                return PL080_WIDTH_32BIT;
+        }
+        return ~0;
+}
+
 static int dma_set_runtime_config(struct dma_chan *chan,
                                   struct dma_slave_config *config)
 {
         struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
         struct pl08x_driver_data *pl08x = plchan->host;
         enum dma_slave_buswidth addr_width;
-        u32 maxburst;
+        u32 width, maxburst;
         u32 cctl = 0;
         int i;
 
@@ -1132,25 +1145,16 @@ static int dma_set_runtime_config(struct dma_chan *chan,
                 return -EINVAL;
         }
 
-        switch (addr_width) {
-        case DMA_SLAVE_BUSWIDTH_1_BYTE:
-                cctl |= (PL080_WIDTH_8BIT << PL080_CONTROL_SWIDTH_SHIFT) |
-                        (PL080_WIDTH_8BIT << PL080_CONTROL_DWIDTH_SHIFT);
-                break;
-        case DMA_SLAVE_BUSWIDTH_2_BYTES:
-                cctl |= (PL080_WIDTH_16BIT << PL080_CONTROL_SWIDTH_SHIFT) |
-                        (PL080_WIDTH_16BIT << PL080_CONTROL_DWIDTH_SHIFT);
-                break;
-        case DMA_SLAVE_BUSWIDTH_4_BYTES:
-                cctl |= (PL080_WIDTH_32BIT << PL080_CONTROL_SWIDTH_SHIFT) |
-                        (PL080_WIDTH_32BIT << PL080_CONTROL_DWIDTH_SHIFT);
-                break;
-        default:
+        width = pl08x_width(addr_width);
+        if (width == ~0) {
                 dev_err(&pl08x->adev->dev,
                         "bad runtime_config: alien address width\n");
                 return -EINVAL;
         }
 
+        cctl |= width << PL080_CONTROL_SWIDTH_SHIFT;
+        cctl |= width << PL080_CONTROL_DWIDTH_SHIFT;
+
         /*
          * Now decide on a maxburst:
          * If this channel will only request single transfers, set this