dmaengine: PL08x: extract function to to generate cctl values

Extract the functionality from dma_slave_config to generate the cctl
values for a given bus width and burst size.  This allows us to use
this elsewhere in the driver, namely the prepare functions.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index bd51a44746bed082b462572f7c968f4d3efaa66b..fde801f787cdcc37ed8f3939061f2ad8c08d346c 100644 (file)
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -1207,14 +1207,40 @@ static u32 pl08x_burst(u32 maxburst)
        return burst_sizes[i].reg;
 }
 
+static u32 pl08x_get_cctl(struct pl08x_dma_chan *plchan,
+       enum dma_slave_buswidth addr_width, u32 maxburst)
+{
+       u32 width, burst, cctl = 0;
+
+       width = pl08x_width(addr_width);
+       if (width == ~0)
+               return ~0;
+
+       cctl |= width << PL080_CONTROL_SWIDTH_SHIFT;
+       cctl |= width << PL080_CONTROL_DWIDTH_SHIFT;
+
+       /*
+        * If this channel will only request single transfers, set this
+        * down to ONE element.  Also select one element if no maxburst
+        * is specified.
+        */
+       if (plchan->cd->single)
+               maxburst = 1;
+
+       burst = pl08x_burst(maxburst);
+       cctl |= burst << PL080_CONTROL_SB_SIZE_SHIFT;
+       cctl |= burst << PL080_CONTROL_DB_SIZE_SHIFT;
+
+       return pl08x_cctl(cctl);
+}
+
 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 width, burst, maxburst;
-       u32 cctl = 0;
+       u32 maxburst, cctl = 0;
 
        if (!plchan->slave)
                return -EINVAL;
@@ -1233,8 +1259,8 @@ static int dma_set_runtime_config(struct dma_chan *chan,
                return -EINVAL;
        }
 
-       width = pl08x_width(addr_width);
-       if (width == ~0) {
+       cctl = pl08x_get_cctl(plchan, addr_width, maxburst);
+       if (cctl == ~0) {
                dev_err(&pl08x->adev->dev,
                        "bad runtime_config: alien address width\n");
                return -EINVAL;
@@ -1242,25 +1268,10 @@ static int dma_set_runtime_config(struct dma_chan *chan,
 
        plchan->cfg = *config;
 
-       cctl |= width << PL080_CONTROL_SWIDTH_SHIFT;
-       cctl |= width << PL080_CONTROL_DWIDTH_SHIFT;
-
-       /*
-        * If this channel will only request single transfers, set this
-        * down to ONE element.  Also select one element if no maxburst
-        * is specified.
-        */
-       if (plchan->cd->single)
-               maxburst = 1;
-
-       burst = pl08x_burst(maxburst);
-       cctl |= burst << PL080_CONTROL_SB_SIZE_SHIFT;
-       cctl |= burst << PL080_CONTROL_DB_SIZE_SHIFT;
-
        if (plchan->runtime_direction == DMA_DEV_TO_MEM) {
-               plchan->src_cctl = pl08x_cctl(cctl);
+               plchan->src_cctl = cctl;
        } else {
-               plchan->dst_cctl = pl08x_cctl(cctl);
+               plchan->dst_cctl = cctl;
        }
 
        dev_dbg(&pl08x->adev->dev,