[RFC 14/34] dmaengine: PL08x: extract function to to generate cctl values
Russell King
rmk+kernel at arm.linux.org.uk
Tue May 29 05:39:59 EDT 2012
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.
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
drivers/dma/amba-pl08x.c | 53 +++++++++++++++++++++++++++------------------
1 files changed, 32 insertions(+), 21 deletions(-)
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index 93ad50d..54aa290 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -1203,14 +1203,40 @@ 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;
@@ -1229,8 +1255,8 @@ 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;
@@ -1238,25 +1264,10 @@ 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,
--
1.7.4.4
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