diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/omap2_mcspi.c | 39 |
1 files changed, 26 insertions, 13 deletions
diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c index 27a3fa1f3bf4..2a651e61bfbf 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) { |