This patch enables word transfer for s3c64xx spi driver. User can set bits_per_word to 32 or 16 or 8, before calling spi_setup, which would enable the corresponding transfer mode.
Change-Id: Ib04f9851a3ea891d2bfa527f2100acd314fe1c98 Signed-off-by: Rajeshwari S Shinde <[email protected]> --- Changes in V2 - Reduced the call for s3c64xx_spi_config. Changes in V3: - Corrected the coding style nits. Chnages in V4: - Add switch case to support both 16 and 32 bit transfer. - Corrected checkpatch error. drivers/spi/spi-s3c64xx.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c index 512b889..1620b74 100644 --- a/drivers/spi/spi-s3c64xx.c +++ b/drivers/spi/spi-s3c64xx.c @@ -491,6 +491,7 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd, { void __iomem *regs = sdd->regs; u32 modecfg, chcfg; + u32 swapcfg = 0; modecfg = readl(regs + S3C64XX_SPI_MODE_CFG); modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON); @@ -498,6 +499,22 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd, chcfg = readl(regs + S3C64XX_SPI_CH_CFG); chcfg &= ~S3C64XX_SPI_CH_TXCH_ON; + switch (sdd->cur_bpw) { + case 32: + swapcfg = S3C64XX_SPI_SWAP_TX_HALF_WORD | + S3C64XX_SPI_SWAP_RX_HALF_WORD; + case 16: + swapcfg |= S3C64XX_SPI_SWAP_TX_EN | + S3C64XX_SPI_SWAP_RX_EN | + S3C64XX_SPI_SWAP_RX_BYTE | + S3C64XX_SPI_SWAP_TX_BYTE; + writel(swapcfg, regs + S3C64XX_SPI_SWAP_CFG); + break; + default: + writel(0, regs + S3C64XX_SPI_SWAP_CFG); + break; + } + if (dma_mode) { chcfg &= ~S3C64XX_SPI_CH_RXCH_ON; } else { @@ -905,13 +922,12 @@ 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; - } + /* + * Enable byte transfer if transfer length not a multiple of + * word size + */ + if (xfer->len % (bpw / 8)) + bpw = 8; if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) { sdd->cur_bpw = bpw; -- 1.7.12.4 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
