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

[Jagan Teki]

Hi,

On Tue, Aug 27, 2013 at 4:11 AM, Asok Subramanian <asok at vyassoft.com> wrote:
>  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

Please use the proper commit head.
Fix problems in chip select selection in imx23,28 spi code
spi: mxs_spi: <EDIT THE TEXT>

--
Thanks,
Jagan.