[PATCH V2 09/20] dmaengine/amba-pl08x: Simplify pl08x_ensure_on()

From: Viresh Kumar
Date: Mon Aug 01 2011 - 05:40:00 EST


Simply writing 1 on bit 0 is sufficient instead of reading and clearing bits.
Also as per manual, for bit 3-31 of DMACConfiguration register:
"read undefined, write as 0"

So, we must not rely on values read from this registers bit 3-31.

Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxx>
Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
drivers/dma/amba-pl08x.c | 8 +-------
1 files changed, 1 insertions(+), 7 deletions(-)

diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index 428a67b..da17249 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -1507,13 +1507,7 @@ bool pl08x_filter_id(struct dma_chan *chan, void *chan_id)
*/
static void pl08x_ensure_on(struct pl08x_driver_data *pl08x)
{
- u32 val;
-
- val = readl(pl08x->base + PL080_CONFIG);
- val &= ~(PL080_CONFIG_M2_BE | PL080_CONFIG_M1_BE | PL080_CONFIG_ENABLE);
- /* We implicitly clear bit 1 and that means little-endian mode */
- val |= PL080_CONFIG_ENABLE;
- writel(val, pl08x->base + PL080_CONFIG);
+ writel(PL080_CONFIG_ENABLE, pl08x->base + PL080_CONFIG);
}

static void pl08x_unmap_buffers(struct pl08x_txd *txd)
--
1.7.2.2

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