On Wed, Oct 20, 2010 at 09:23:57AM -0700, Tony Lindgren wrote:
> * Ilkka Koskinen <[email protected]> [101019 06:55]:
> > In case of TX only with DMA, the driver assumes that the data
> > has been transferred once DMA callback in invoked. However,
> > SPI's shift register may still contain data. Thus, the driver
> > is supposed to verify that the register is empty and the end of
> > the SPI transfer has been reached.
> >
> > Signed-off-by: Ilkka Koskinen <[email protected]>
> > Tested-by: Tuomas Katila <[email protected]>
>
> Grant, can you please queue this one?
>
> Acked-by: Tony Lindgren <[email protected]>
Applied, thanks.
g.
>
>
> > ---
> > 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 b3a94ca..a2e053c 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)
> > {
> > --
> > 1.6.0.4
> >
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