[PATCH v1 2/3] spi: s3c64xx: Added provision for dedicated cs pin

Girish KS girishks2000 at gmail.com
Thu Jun 20 05:22:07 EDT 2013


On Wed, Jun 19, 2013 at 11:53 PM, Mark Brown <broonie at kernel.org> wrote:
> On Mon, May 20, 2013 at 12:21:33PM +0530, Girish K S wrote:
>> From: Girish K S <girishks2000 at gmail.com>
>>
>> The existing driver supports gpio based /cs signal.
>> For controller's that have one device per controller,
>> the slave device's /cs signal might be internally controlled
>> by the chip select bit of slave select register. They are not
>> externally asserted/deasserted using gpio pin.
>>
>> This patch adds support for controllers with dedicated /cs pin.
>> if "cs-gpio" property doesnt exist in a spi dts node, the controller
>> would treat the /cs pin as dedicated.
>
> This breaks SPI operation on my s3c64xx based system since...
>
>>       if (pdev->dev.of_node) {
>> +             if (of_find_property(pdev->dev.of_node, "cs-gpio", NULL))
>> +                     sdd->cs_gpio = true;
>> +
>>               ret = of_alias_get_id(pdev->dev.of_node, "spi");
>>               if (ret < 0) {
>>                       dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
>
> sdd->cs_gpio is only set to true by this code so if you're using a board
> file then the GPIO will be ignored.

Reversing the default assignment for "sdd->cs_gpio" and the following
"if condition" shall handle both dt and non-dt case. Will do it and
resubmit only this patch in the series.



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