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

[Jagan Teki]

Hi,

Try to fix the above issues.
Use u-boot-spi.git repo with master-probe branch.
Please test the same on your hw and let me know for any issues.

On Tue, Aug 27, 2013 at 6:54 PM, Jagan Teki <jagannadh.teki at gmail.com> wrote:
> On Tue, Aug 27, 2013 at 2:40 PM, Jagan Teki <jagannadh.teki at gmail.com> wrote:
>> 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>
>
> And also please fix the check-patch errors:
>
> ERROR: Unrecognized email address: 'Asok Subramanian <asok at vyassoft.com>'
> #18:
> Signed-off-by: Asok Subramanian <asok at vyassoft.com>
>
> ERROR: patch seems to be corrupt (line wrapped?)
> #29: FILE: drivers/spi/mxs_spi.c:31:
>      uint32_t        max_khz;
>
> WARNING: line over 80 characters
> #49: FILE: drivers/spi/mxs_spi.c:104:
> +    writel(SSP_CTRL0_BUS_WIDTH_ONE_BIT | (mxs_slave->cs) <<
> MXS_SSP_CHIPSELECT_SHIFT, &ssp_regs->hw_ssp_ctrl0);
>
> total: 2 errors, 1 warnings, 22 lines checked
>
>
> --
> Thanks,
> Jagan.



-- 
Thanks,
Jagan.
--------
Jagannadha Sutradharudu Teki,
E: jagannadh.teki at gmail.com, P: +91-9676773388
Engineer - System Software Hacker
U-boot - SPI Custodian and Zynq APSOC
Ln: http://www.linkedin.com/in/jaganteki