diff options
Diffstat (limited to 'drivers/spi/spi-s3c64xx.c')
-rw-r--r-- | drivers/spi/spi-s3c64xx.c | 207 |
1 files changed, 99 insertions, 108 deletions
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c index ae907dde1371..25c9bd409a87 100644 --- a/drivers/spi/spi-s3c64xx.c +++ b/drivers/spi/spi-s3c64xx.c @@ -381,7 +381,7 @@ static void s3c64xx_spi_dma_stop(struct s3c64xx_spi_driver_data *sdd, #else static void prepare_dma(struct s3c64xx_spi_dma_data *dma, - unsigned len, dma_addr_t buf) + struct sg_table *sgt) { struct s3c64xx_spi_driver_data *sdd; struct dma_slave_config config; @@ -407,8 +407,8 @@ static void prepare_dma(struct s3c64xx_spi_dma_data *dma, dmaengine_slave_config(dma->ch, &config); } - desc = dmaengine_prep_slave_single(dma->ch, buf, len, - dma->direction, DMA_PREP_INTERRUPT); + desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents, + dma->direction, DMA_PREP_INTERRUPT); desc->callback = s3c64xx_spi_dmacb; desc->callback_param = dma; @@ -515,7 +515,11 @@ 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; +#ifndef CONFIG_S3C_DMA + prepare_dma(&sdd->tx_dma, &xfer->tx_sg); +#else prepare_dma(&sdd->tx_dma, xfer->len, xfer->tx_dma); +#endif } else { switch (sdd->cur_bpw) { case 32: @@ -547,7 +551,11 @@ 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); +#ifndef CONFIG_S3C_DMA + prepare_dma(&sdd->rx_dma, &xfer->rx_sg); +#else prepare_dma(&sdd->rx_dma, xfer->len, xfer->rx_dma); +#endif } } @@ -555,23 +563,6 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd, writel(chcfg, regs + S3C64XX_SPI_CH_CFG); } -static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd, - struct spi_device *spi) -{ - if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */ - if (sdd->tgl_spi != spi) { /* if last mssg on diff device */ - /* Deselect the last toggled device */ - if (spi->cs_gpio >= 0) - gpio_set_value(spi->cs_gpio, - spi->mode & SPI_CS_HIGH ? 0 : 1); - } - sdd->tgl_spi = NULL; - } - - if (spi->cs_gpio >= 0) - gpio_set_value(spi->cs_gpio, spi->mode & SPI_CS_HIGH ? 1 : 0); -} - static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd, int timeout_ms) { @@ -593,112 +584,111 @@ static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd, return RX_FIFO_LVL(status, sdd); } -static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd, - struct spi_transfer *xfer, int dma_mode) +static int wait_for_dma(struct s3c64xx_spi_driver_data *sdd, + struct spi_transfer *xfer) { void __iomem *regs = sdd->regs; unsigned long val; + u32 status; int ms; /* millisecs to xfer 'len' bytes @ 'cur_speed' */ ms = xfer->len * 8 * 1000 / sdd->cur_speed; ms += 10; /* some tolerance */ - if (dma_mode) { - val = msecs_to_jiffies(ms) + 10; - val = wait_for_completion_timeout(&sdd->xfer_completion, val); - } else { - u32 status; - val = msecs_to_loops(ms); - do { + val = msecs_to_jiffies(ms) + 10; + val = wait_for_completion_timeout(&sdd->xfer_completion, val); + + /* + * If the previous xfer was completed within timeout, then + * proceed further else return -EIO. + * DmaTx returns after simply writing data in the FIFO, + * w/o waiting for real transmission on the bus to finish. + * DmaRx returns only after Dma read data from FIFO which + * needs bus transmission to finish, so we don't worry if + * Xfer involved Rx(with or without Tx). + */ + if (val && !xfer->rx_buf) { + val = msecs_to_loops(10); + status = readl(regs + S3C64XX_SPI_STATUS); + while ((TX_FIFO_LVL(status, sdd) + || !S3C64XX_SPI_ST_TX_DONE(status, sdd)) + && --val) { + cpu_relax(); status = readl(regs + S3C64XX_SPI_STATUS); - } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val); + } + } - if (dma_mode) { - u32 status; - - /* - * If the previous xfer was completed within timeout, then - * proceed further else return -EIO. - * DmaTx returns after simply writing data in the FIFO, - * w/o waiting for real transmission on the bus to finish. - * DmaRx returns only after Dma read data from FIFO which - * needs bus transmission to finish, so we don't worry if - * Xfer involved Rx(with or without Tx). - */ - if (val && !xfer->rx_buf) { - val = msecs_to_loops(10); - status = readl(regs + S3C64XX_SPI_STATUS); - while ((TX_FIFO_LVL(status, sdd) - || !S3C64XX_SPI_ST_TX_DONE(status, sdd)) - && --val) { - cpu_relax(); - status = readl(regs + S3C64XX_SPI_STATUS); - } + /* If timed out while checking rx/tx status return error */ + if (!val) + return -EIO; - } + return 0; +} - /* If timed out while checking rx/tx status return error */ - if (!val) - return -EIO; - } else { - int loops; - u32 cpy_len; - u8 *buf; - - /* If it was only Tx */ - if (!xfer->rx_buf) { - sdd->state &= ~TXBUSY; - return 0; - } +static int wait_for_pio(struct s3c64xx_spi_driver_data *sdd, + struct spi_transfer *xfer) +{ + void __iomem *regs = sdd->regs; + unsigned long val; + u32 status; + int loops; + u32 cpy_len; + u8 *buf; + int ms; - /* - * If the receive length is bigger than the controller fifo - * size, calculate the loops and read the fifo as many times. - * loops = length / max fifo size (calculated by using the - * fifo mask). - * For any size less than the fifo size the below code is - * executed atleast once. - */ - loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1); - buf = xfer->rx_buf; - do { - /* wait for data to be received in the fifo */ - cpy_len = s3c64xx_spi_wait_for_timeout(sdd, - (loops ? ms : 0)); + /* millisecs to xfer 'len' bytes @ 'cur_speed' */ + ms = xfer->len * 8 * 1000 / sdd->cur_speed; + ms += 10; /* some tolerance */ - switch (sdd->cur_bpw) { - case 32: - ioread32_rep(regs + S3C64XX_SPI_RX_DATA, - buf, cpy_len / 4); - break; - case 16: - ioread16_rep(regs + S3C64XX_SPI_RX_DATA, - buf, cpy_len / 2); - break; - default: - ioread8_rep(regs + S3C64XX_SPI_RX_DATA, - buf, cpy_len); - break; - } + val = msecs_to_loops(ms); + do { + status = readl(regs + S3C64XX_SPI_STATUS); + } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val); - buf = buf + cpy_len; - } while (loops--); - sdd->state &= ~RXBUSY; + + /* If it was only Tx */ + if (!xfer->rx_buf) { + sdd->state &= ~TXBUSY; + return 0; } - return 0; -} + /* + * If the receive length is bigger than the controller fifo + * size, calculate the loops and read the fifo as many times. + * loops = length / max fifo size (calculated by using the + * fifo mask). + * For any size less than the fifo size the below code is + * executed atleast once. + */ + loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1); + buf = xfer->rx_buf; + do { + /* wait for data to be received in the fifo */ + cpy_len = s3c64xx_spi_wait_for_timeout(sdd, + (loops ? ms : 0)); + + switch (sdd->cur_bpw) { + case 32: + ioread32_rep(regs + S3C64XX_SPI_RX_DATA, + buf, cpy_len / 4); + break; + case 16: + ioread16_rep(regs + S3C64XX_SPI_RX_DATA, + buf, cpy_len / 2); + break; + default: + ioread8_rep(regs + S3C64XX_SPI_RX_DATA, + buf, cpy_len); + break; + } -static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd, - struct spi_device *spi) -{ - if (sdd->tgl_spi == spi) - sdd->tgl_spi = NULL; + buf = buf + cpy_len; + } while (loops--); + sdd->state &= ~RXBUSY; - if (spi->cs_gpio >= 0) - gpio_set_value(spi->cs_gpio, spi->mode & SPI_CS_HIGH ? 0 : 1); + return 0; } static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd) @@ -929,7 +919,10 @@ static int s3c64xx_spi_transfer_one(struct spi_master *master, spin_unlock_irqrestore(&sdd->lock, flags); - status = wait_for_xfer(sdd, xfer, use_dma); + if (use_dma) + status = wait_for_dma(sdd, xfer); + else + status = wait_for_pio(sdd, xfer); if (status) { dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n", @@ -1092,14 +1085,12 @@ static int s3c64xx_spi_setup(struct spi_device *spi) pm_runtime_put(&sdd->pdev->dev); writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); - disable_cs(sdd, spi); return 0; setup_exit: pm_runtime_put(&sdd->pdev->dev); /* setup() returns with device de-selected */ writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); - disable_cs(sdd, spi); gpio_free(cs->line); spi_set_ctldata(spi, NULL); |