From 0c92ecf10d9fb80b1798d2a9adfdea17f8f5e6d9 Mon Sep 17 00:00:00 2001 From: Jassi Brar Date: Wed, 29 Sep 2010 17:31:33 +0900 Subject: [PATCH] spi/s3c64xx: Correction for 16,32 bits bus width We can't do without setting channel and bus width to same size. In order to do that, use loop read/writes in polling mode and appropriate burst size in DMA mode. Signed-off-by: Jassi Brar Signed-off-by: Grant Likely --- drivers/spi/spi_s3c64xx.c | 56 ++++++++++++++++++++++++++++----------- 1 file changed, 41 insertions(+), 15 deletions(-) diff --git a/drivers/spi/spi_s3c64xx.c b/drivers/spi/spi_s3c64xx.c index 9e0aa3c7b4d1..795828b90f45 100644 --- a/drivers/spi/spi_s3c64xx.c +++ b/drivers/spi/spi_s3c64xx.c @@ -261,15 +261,25 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd, chcfg |= S3C64XX_SPI_CH_TXCH_ON; if (dma_mode) { modecfg |= S3C64XX_SPI_MODE_TXDMA_ON; - s3c2410_dma_config(sdd->tx_dmach, 1); + s3c2410_dma_config(sdd->tx_dmach, sdd->cur_bpw / 8); s3c2410_dma_enqueue(sdd->tx_dmach, (void *)sdd, xfer->tx_dma, xfer->len); s3c2410_dma_ctrl(sdd->tx_dmach, S3C2410_DMAOP_START); } else { - unsigned char *buf = (unsigned char *) xfer->tx_buf; - int i = 0; - while (i < xfer->len) - writeb(buf[i++], regs + S3C64XX_SPI_TX_DATA); + switch (sdd->cur_bpw) { + case 32: + iowrite32_rep(regs + S3C64XX_SPI_TX_DATA, + xfer->tx_buf, xfer->len / 4); + break; + case 16: + iowrite16_rep(regs + S3C64XX_SPI_TX_DATA, + xfer->tx_buf, xfer->len / 2); + break; + default: + iowrite8_rep(regs + S3C64XX_SPI_TX_DATA, + xfer->tx_buf, xfer->len); + break; + } } } @@ -286,7 +296,7 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd, writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff) | S3C64XX_SPI_PACKET_CNT_EN, regs + S3C64XX_SPI_PACKET_CNT); - s3c2410_dma_config(sdd->rx_dmach, 1); + s3c2410_dma_config(sdd->rx_dmach, sdd->cur_bpw / 8); s3c2410_dma_enqueue(sdd->rx_dmach, (void *)sdd, xfer->rx_dma, xfer->len); s3c2410_dma_ctrl(sdd->rx_dmach, S3C2410_DMAOP_START); @@ -366,20 +376,26 @@ static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd, return -EIO; } } else { - unsigned char *buf; - int i; - /* If it was only Tx */ if (xfer->rx_buf == NULL) { sdd->state &= ~TXBUSY; return 0; } - i = 0; - buf = xfer->rx_buf; - while (i < xfer->len) - buf[i++] = readb(regs + S3C64XX_SPI_RX_DATA); - + switch (sdd->cur_bpw) { + case 32: + ioread32_rep(regs + S3C64XX_SPI_RX_DATA, + xfer->rx_buf, xfer->len / 4); + break; + case 16: + ioread16_rep(regs + S3C64XX_SPI_RX_DATA, + xfer->rx_buf, xfer->len / 2); + break; + default: + ioread8_rep(regs + S3C64XX_SPI_RX_DATA, + xfer->rx_buf, xfer->len); + break; + } sdd->state &= ~RXBUSY; } @@ -434,15 +450,17 @@ static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd) switch (sdd->cur_bpw) { case 32: val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD; + val |= S3C64XX_SPI_MODE_CH_TSZ_WORD; break; case 16: val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD; + val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD; break; default: val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE; + val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE; break; } - val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE; /* Always 8bits wide */ writel(val, regs + S3C64XX_SPI_MODE_CFG); @@ -629,6 +647,14 @@ static void handle_msg(struct s3c64xx_spi_driver_data *sdd, bpw = xfer->bits_per_word ? : spi->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 (bpw != sdd->cur_bpw || speed != sdd->cur_speed) { sdd->cur_bpw = bpw; sdd->cur_speed = speed;