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authorJassi Brar <jassi.brar@samsung.com>2010-09-29 17:31:31 +0900
committerGrant Likely <grant.likely@secretlab.ca>2010-09-29 17:31:31 +0900
commite02ddd442a532c73e547ae3735c8012e3bd719a5 (patch)
tree68343f5c171c15286c275d40dd2bc2577daa5845 /drivers
parent4a4fd47155ac49b62de5177a780c245e967752f3 (diff)
spi/s3c64xx: Prevent unnecessary map-unmap
Since we use DMA mode only for xfers bigger than FIFO size, do not map/unmap buffers for polling mode transfers. Signed-off-by: Jassi Brar <jassi.brar@samsung.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/spi/spi_s3c64xx.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/spi/spi_s3c64xx.c b/drivers/spi/spi_s3c64xx.c
index c3038da2648..e7b893f2a21 100644
--- a/drivers/spi/spi_s3c64xx.c
+++ b/drivers/spi/spi_s3c64xx.c
@@ -499,6 +499,7 @@ static void s3c64xx_spi_dma_txcb(struct s3c2410_dma_chan *chan, void *buf_id,
static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
struct spi_message *msg)
{
+ struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
struct device *dev = &sdd->pdev->dev;
struct spi_transfer *xfer;
@@ -514,6 +515,9 @@ static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
/* Map until end or first fail */
list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+ if (xfer->len <= ((sci->fifo_lvl_mask >> 1) + 1))
+ continue;
+
if (xfer->tx_buf != NULL) {
xfer->tx_dma = dma_map_single(dev,
(void *)xfer->tx_buf, xfer->len,
@@ -545,6 +549,7 @@ static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
struct spi_message *msg)
{
+ struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
struct device *dev = &sdd->pdev->dev;
struct spi_transfer *xfer;
@@ -553,6 +558,9 @@ static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+ if (xfer->len <= ((sci->fifo_lvl_mask >> 1) + 1))
+ continue;
+
if (xfer->rx_buf != NULL
&& xfer->rx_dma != XFER_DMAADDR_INVALID)
dma_unmap_single(dev, xfer->rx_dma,