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spi/s3c64xx: Prevent unnecessary map-unmap

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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>
This commit is contained in:
Jassi Brar 2010-09-29 17:31:31 +09:00 committed by Grant Likely
parent 4a4fd47155
commit e02ddd442a
1 changed files with 8 additions and 0 deletions
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8
drivers/spi/spi_s3c64xx.c
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@ -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,