Hi Thomas,
2015-10-09 9:52 GMT+02:00 Thomas Petazzoni
<thomas.petazz...@free-electrons.com>:
> Dear Marcin Wojtas,
>
> On Fri, 9 Oct 2015 03:03:53 +0200, Marcin Wojtas wrote:
>> The newest revisions of A388-GP (v1.5 and higher) support only
>> DAT3-based card detection. Revisions < v1.5 based on GPIO detection
>> via I2C expander, but this solution is supposed to be deprecated on
>> new boards. In order to satisfy all type of hardware this commit
>> changes card detection to use software polling mechanism.
>>
>> Signed-off-by: Marcin Wojtas <m...@semihalf.com>
>
> Can we add a comment on the DT that explains why SW polling is used,
> and which other mechanism can be used depending on the board revision?
Sure, good idea. Do you think the below would be sufficient?
sdhci@d8000 {
pinctrl-names = "default";
pinctrl-0 = <&sdhci_pins>;
no-1-8-v;
/*
* A388-GP board v1.5 and higher replace
* hitherto card detection method based on GPIO
* with the one using DAT3 pin. As they are
* incompatible, software-based polling is
* enabled with 'broken-cd' property. For boards
* older than v1.5 it can be replaced with:
* 'cd-gpios = <&expander0 5 GPIO_ACTIVE_LOW>;',
* whereas for the newer ones following can be
* used instead:
* 'dat3-cd;'
* 'cd-inverted;'
*/
broken-cd;
wp-inverted;
bus-width = <8>;
status = "okay";
};
Best regards,
Marcin
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