This patch enables word transfer for s3c64xx spi driver.
User can set bits_per_word to 32 before calling spi_setup,
which would enable the word transfer mode.
Signed-off-by: Rajeshwari S Shinde <rajeshwari.s@xxxxxxxxxxx>
---
drivers/spi/spi-s3c64xx.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 512b889..893361b 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -498,6 +498,17 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
+ if(sdd->cur_bpw == 32) {
+ /* For word transfer we need to swap bytes */
+ u32 swapcfg = (S3C64XX_SPI_SWAP_TX_EN | S3C64XX_SPI_SWAP_TX_BYTE |
+ S3C64XX_SPI_SWAP_TX_HALF_WORD |
+ S3C64XX_SPI_SWAP_RX_EN |
+ S3C64XX_SPI_SWAP_RX_BYTE |
+ S3C64XX_SPI_SWAP_RX_HALF_WORD);
+ writel(swapcfg, regs + S3C64XX_SPI_SWAP_CFG);
+ } else
+ writel(0, regs + S3C64XX_SPI_SWAP_CFG);
+
if (dma_mode) {
chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
} else {
@@ -905,19 +916,16 @@ static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
bpw = xfer->bits_per_word;
speed = xfer->speed_hz ? : spi->max_speed_hz;
- if (xfer->len % (bpw / 8)) {
- dev_err(&spi->dev,
- "Xfer length(%u) not a multiple of word size(%u)\n",
- xfer->len, bpw / 8);
- status = -EIO;
- goto out;
+ if (speed != sdd->cur_speed) {
+ sdd->cur_speed = speed;
}
- if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
+ if (xfer->len % (bpw / 8))
+ sdd->cur_bpw = 8;
+ else
sdd->cur_bpw = bpw;
- sdd->cur_speed = speed;
- s3c64xx_spi_config(sdd);
- }
+
+ s3c64xx_spi_config(sdd);
/* Polling method for xfers not bigger than FIFO capacity */
use_dma = 0;
--
1.7.12.4
--
To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
