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| author | Jassi Brar <jassi.brar@samsung.com> | 2010-09-29 17:31:31 +0900 |
|---|---|---|
| committer | Grant Likely <grant.likely@secretlab.ca> | 2010-09-29 17:31:31 +0900 |
| commit | e02ddd442a532c73e547ae3735c8012e3bd719a5 (patch) | |
| tree | 68343f5c171c15286c275d40dd2bc2577daa5845 | |
| parent | 4a4fd47155ac49b62de5177a780c245e967752f3 (diff) | |
| download | kernel_samsung_smdk4412-e02ddd442a532c73e547ae3735c8012e3bd719a5.zip kernel_samsung_smdk4412-e02ddd442a532c73e547ae3735c8012e3bd719a5.tar.gz kernel_samsung_smdk4412-e02ddd442a532c73e547ae3735c8012e3bd719a5.tar.bz2 | |
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>
| -rw-r--r-- | drivers/spi/spi_s3c64xx.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/spi/spi_s3c64xx.c b/drivers/spi/spi_s3c64xx.c index c3038da..e7b893f 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, |