[PATCH] SPI: remove superfluous DMA buffer syncs on PL022
Linus Walleij
linus.walleij at stericsson.com
Tue Aug 17 18:08:44 EDT 2010
This removes the superfluous DMA buffer syncs identified by Russell
in the DMA support for PL022.
Cc: yuanyabin1978 at sina.com
Cc: Dan Williams <dan.j.williams at intel.com>
Cc: Russell King <linux at arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij at stericsson.com>
---
drivers/spi/amba-pl022.c | 16 +++++-----------
1 files changed, 5 insertions(+), 11 deletions(-)
diff --git a/drivers/spi/amba-pl022.c b/drivers/spi/amba-pl022.c
index 59b3948..521d3d9 100644
--- a/drivers/spi/amba-pl022.c
+++ b/drivers/spi/amba-pl022.c
@@ -794,12 +794,7 @@ static void dma_callback(void *data)
struct pl022 *pl022 = data;
struct spi_message *msg = pl022->cur_msg;
- /* Sync in RX buffer to CPU */
BUG_ON(!pl022->sgt_rx.sgl);
- dma_sync_sg_for_cpu(&pl022->adev->dev,
- pl022->sgt_rx.sgl,
- pl022->sgt_rx.nents,
- DMA_FROM_DEVICE);
#ifdef VERBOSE_DEBUG
/*
@@ -812,6 +807,11 @@ static void dma_callback(void *data)
struct scatterlist *sg;
unsigned int i;
+ dma_sync_sg_for_cpu(&pl022->adev->dev,
+ pl022->sgt_rx.sgl,
+ pl022->sgt_rx.nents,
+ DMA_FROM_DEVICE);
+
for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
print_hex_dump(KERN_ERR, "SPI RX: ",
@@ -1001,12 +1001,6 @@ static int configure_dma(struct pl022 *pl022)
if (sglen != pages)
goto err_tx_sgmap;
- /* Synchronize the TX scatterlist, invalidate buffers, caches etc */
- dma_sync_sg_for_device(&pl022->adev->dev,
- pl022->sgt_tx.sgl,
- pl022->sgt_tx.nents,
- DMA_TO_DEVICE);
-
/* Send both scatterlists */
rxdesc = rxchan->device->device_prep_slave_sg(rxchan,
pl022->sgt_rx.sgl,
--
1.6.3.3
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