[U-Boot] [PATCH V2] spi: mxs: Configure chipselect after block reset

[Stefano Babic <sbabic@denx.de>]

On 27/08/2013 11:05, Marek Vasut wrote:
> Dear Stefano Babic,
> 
>> On 26/08/2013 17:45, Marek Vasut wrote:
>>> The chipselect must be written into the CTRL0 register after the SSP
>>> block is reset, otherwise the block will always use ChipSelect #0.
>>>
>>> Signed-off-by: Marek Vasut <marex@denx.de>
>>> Cc: Fabio Estevam <fabio.estevam@freescale.com>
>>> Cc: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
>>> Cc: Otavio Salvador <otavio@ossystems.com.br>
>>> Cc: Stefano Babic <sbabic@denx.de>
>>> ---
>>>
>>>  drivers/spi/mxs_spi.c |   12 +++---------
>>>  1 file changed, 3 insertions(+), 9 deletions(-)
>>>
>>> V2: Clean up a warning that "ssp_regs" are not used
>>>
>>> diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c
>>> index 3cf7142..2b9f395 100644
>>> --- a/drivers/spi/mxs_spi.c
>>> +++ b/drivers/spi/mxs_spi.c
>>> @@ -56,8 +56,6 @@ struct spi_slave *spi_setup_slave(unsigned int bus,
>>> unsigned int cs,
>>>
>>>  				  unsigned int max_hz, unsigned int mode)
>>>  
>>>  {
>>>  
>>>  	struct mxs_spi_slave *mxs_slave;
>>>
>>> -	struct mxs_ssp_regs *ssp_regs;
>>> -	int reg;
>>>
>>>  	if (!spi_cs_is_valid(bus, cs)) {
>>>  	
>>>  		printf("mxs_spi: invalid bus %d / chip select %d\n", bus, cs);
>>>
>>> @@ -74,13 +72,7 @@ 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);
>>>
>>> -	ssp_regs = mxs_slave->regs;
>>>
>>> -	reg = readl(&ssp_regs->hw_ssp_ctrl0);
>>> -	reg &= ~(MXS_SSP_CHIPSELECT_MASK);
>>> -	reg |= cs << MXS_SSP_CHIPSELECT_SHIFT;
>>> -
>>> -	writel(reg, &ssp_regs->hw_ssp_ctrl0);
>>>
>>>  	return &mxs_slave->slave;
>>>  
>>>  err_init:
>>> @@ -102,7 +94,9 @@ 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((slave->cs << MXS_SSP_CHIPSELECT_SHIFT) |
>>> +	       SSP_CTRL0_BUS_WIDTH_ONE_BIT,
>>> +	       &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;
>>
>> Acked-by: Stefano Babic <sbabic@denx.de>
> 
> Can we push this via IMX tree ?

Maybe, but correctly this should be push via u-boot-spi.

Best regards,
Stefano Babic

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