diff options
Diffstat (limited to 'drivers/spi/omap2_mcspi.c')
-rw-r--r-- | drivers/spi/omap2_mcspi.c | 81 |
1 files changed, 41 insertions, 40 deletions
diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c index b3a94ca0a75..2a651e61bfb 100644 --- a/drivers/spi/omap2_mcspi.c +++ b/drivers/spi/omap2_mcspi.c @@ -296,6 +296,19 @@ static int omap2_mcspi_enable_clocks(struct omap2_mcspi *mcspi) return 0; } +static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit) +{ + unsigned long timeout; + + timeout = jiffies + msecs_to_jiffies(1000); + while (!(__raw_readl(reg) & bit)) { + if (time_after(jiffies, timeout)) + return -1; + cpu_relax(); + } + return 0; +} + static unsigned omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) { @@ -309,11 +322,14 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) u32 l; u8 * rx; const u8 * tx; + void __iomem *chstat_reg; mcspi = spi_master_get_devdata(spi->master); mcspi_dma = &mcspi->dma_channels[spi->chip_select]; l = mcspi_cached_chconf0(spi); + chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; + count = xfer->len; c = count; word_len = cs->word_len; @@ -382,6 +398,16 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) if (tx != NULL) { wait_for_completion(&mcspi_dma->dma_tx_completion); dma_unmap_single(NULL, xfer->tx_dma, count, DMA_TO_DEVICE); + + /* for TX_ONLY mode, be sure all words have shifted out */ + if (rx == NULL) { + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXS) < 0) + dev_err(&spi->dev, "TXS timed out\n"); + else if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_EOT) < 0) + dev_err(&spi->dev, "EOT timed out\n"); + } } if (rx != NULL) { @@ -435,19 +461,6 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) return count; } -static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit) -{ - unsigned long timeout; - - timeout = jiffies + msecs_to_jiffies(1000); - while (!(__raw_readl(reg) & bit)) { - if (time_after(jiffies, timeout)) - return -1; - cpu_relax(); - } - return 0; -} - static unsigned omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) { @@ -489,10 +502,8 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) dev_err(&spi->dev, "TXS timed out\n"); goto out; } -#ifdef VERBOSE - dev_dbg(&spi->dev, "write-%d %02x\n", + dev_vdbg(&spi->dev, "write-%d %02x\n", word_len, *tx); -#endif __raw_writel(*tx++, tx_reg); } if (rx != NULL) { @@ -506,10 +517,8 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) (l & OMAP2_MCSPI_CHCONF_TURBO)) { omap2_mcspi_set_enable(spi, 0); *rx++ = __raw_readl(rx_reg); -#ifdef VERBOSE - dev_dbg(&spi->dev, "read-%d %02x\n", + dev_vdbg(&spi->dev, "read-%d %02x\n", word_len, *(rx - 1)); -#endif if (mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS) < 0) { dev_err(&spi->dev, @@ -522,10 +531,8 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) } *rx++ = __raw_readl(rx_reg); -#ifdef VERBOSE - dev_dbg(&spi->dev, "read-%d %02x\n", + dev_vdbg(&spi->dev, "read-%d %02x\n", word_len, *(rx - 1)); -#endif } } while (c); } else if (word_len <= 16) { @@ -542,10 +549,8 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) dev_err(&spi->dev, "TXS timed out\n"); goto out; } -#ifdef VERBOSE - dev_dbg(&spi->dev, "write-%d %04x\n", + dev_vdbg(&spi->dev, "write-%d %04x\n", word_len, *tx); -#endif __raw_writel(*tx++, tx_reg); } if (rx != NULL) { @@ -559,10 +564,8 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) (l & OMAP2_MCSPI_CHCONF_TURBO)) { omap2_mcspi_set_enable(spi, 0); *rx++ = __raw_readl(rx_reg); -#ifdef VERBOSE - dev_dbg(&spi->dev, "read-%d %04x\n", + dev_vdbg(&spi->dev, "read-%d %04x\n", word_len, *(rx - 1)); -#endif if (mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS) < 0) { dev_err(&spi->dev, @@ -575,10 +578,8 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) } *rx++ = __raw_readl(rx_reg); -#ifdef VERBOSE - dev_dbg(&spi->dev, "read-%d %04x\n", + dev_vdbg(&spi->dev, "read-%d %04x\n", word_len, *(rx - 1)); -#endif } } while (c); } else if (word_len <= 32) { @@ -595,10 +596,8 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) dev_err(&spi->dev, "TXS timed out\n"); goto out; } -#ifdef VERBOSE - dev_dbg(&spi->dev, "write-%d %08x\n", + dev_vdbg(&spi->dev, "write-%d %08x\n", word_len, *tx); -#endif __raw_writel(*tx++, tx_reg); } if (rx != NULL) { @@ -612,10 +611,8 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) (l & OMAP2_MCSPI_CHCONF_TURBO)) { omap2_mcspi_set_enable(spi, 0); *rx++ = __raw_readl(rx_reg); -#ifdef VERBOSE - dev_dbg(&spi->dev, "read-%d %08x\n", + dev_vdbg(&spi->dev, "read-%d %08x\n", word_len, *(rx - 1)); -#endif if (mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS) < 0) { dev_err(&spi->dev, @@ -628,10 +625,8 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) } *rx++ = __raw_readl(rx_reg); -#ifdef VERBOSE - dev_dbg(&spi->dev, "read-%d %08x\n", + dev_vdbg(&spi->dev, "read-%d %08x\n", word_len, *(rx - 1)); -#endif } } while (c); } @@ -644,6 +639,12 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) } else if (mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_EOT) < 0) dev_err(&spi->dev, "EOT timed out\n"); + + /* disable chan to purge rx datas received in TX_ONLY transfer, + * otherwise these rx datas will affect the direct following + * RX_ONLY transfer. + */ + omap2_mcspi_set_enable(spi, 0); } out: omap2_mcspi_set_enable(spi, 1); |