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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 <jassi.brar@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This commit is contained in:
Jassi Brar 2010-09-29 17:31:33 +09:00 committed by Grant Likely
parent b42a81ca0f
commit 0c92ecf10d
1 changed files with 41 additions and 15 deletions
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56
drivers/spi/spi_s3c64xx.c
View File

@ -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;