Documentation clearly states, that mode should not be changed
till SPMODE_ENABLE bit set. I've seen hangs w/o this patch.

Signed-off-by: Anton Vorontsov <[EMAIL PROTECTED]>
---
 drivers/spi/spi_mpc83xx.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 3295cfc..0b99fd9 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -176,6 +176,8 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, 
int value)
                        regval |= SPMODE_PM(pm);
                }
 
+               /* Turn off SPI unit prior changing mode */
+               mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
                mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
                if (mpc83xx_spi->activate_cs)
                        mpc83xx_spi->activate_cs(spi->chip_select, pol);
@@ -249,6 +251,8 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, 
struct spi_transfer *t)
        regval &= 0xff0fffff;
        regval |= SPMODE_LEN(bits_per_word);
 
+       /* Turn off SPI unit prior changing mode */
+       mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
        mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
 
        return 0;
-- 
1.5.0.6

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