[U-Boot] [PATCH] Fix problems in chip select selection in imx23, 28 spi code

[Asok Subramanian]

 Fix problems in chip select selection in imx23,28 spi code

The spi function code for imx23,28 currently does not work for chip select other than 0.
This is because the register HW_SSP_CTRL0 is first  reset and the code does not load the CS bits
again into HW_SSP_CTRL0 after the reset. The proposed fix reloads the CS bits after the reset.

Signed-off-by: Asok Subramanian <asok at vyassoft.com>
---
 drivers/spi/mxs_spi.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c
index 3cf7142..15681dc 100644
--- a/drivers/spi/mxs_spi.c
+++ b/drivers/spi/mxs_spi.c
@@ -32,6 +32,7 @@ struct mxs_spi_slave {
     uint32_t        max_khz;
     uint32_t        mode;
     struct mxs_ssp_regs    *regs;
+    unsigned int            cs;
 };
 
 static inline struct mxs_spi_slave *to_mxs_slave(struct spi_slave *slave)
@@ -74,6 +75,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
     mxs_slave->max_khz = max_hz / 1000;
     mxs_slave->mode = mode;
     mxs_slave->regs = mxs_ssp_regs_by_bus(bus);
+    mxs_slave->cs = cs;
     ssp_regs = mxs_slave->regs;
 
     reg = readl(&ssp_regs->hw_ssp_ctrl0);
@@ -102,7 +104,7 @@ int spi_claim_bus(struct spi_slave *slave)
 
     mxs_reset_block(&ssp_regs->hw_ssp_ctrl0_reg);
 
-    writel(SSP_CTRL0_BUS_WIDTH_ONE_BIT, &ssp_regs->hw_ssp_ctrl0);
+    writel(SSP_CTRL0_BUS_WIDTH_ONE_BIT | (mxs_slave->cs) << MXS_SSP_CHIPSELECT_SHIFT, &ssp_regs->hw_ssp_ctrl0);
 
     reg = SSP_CTRL1_SSP_MODE_SPI | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS;
     reg |= (mxs_slave->mode & SPI_CPOL) ? SSP_CTRL1_POLARITY : 0;
-- 
1.7.9.5