On 2/18/19 11:18 PM, Harald Geyer wrote:
> Marek Vasut writes:
>> So what about
>>
>> gpios-states : Initial state of GPIO pins in "gpios" array, set on
>> system start and retained until consumer changes the state. 0: LOW, 1:
>> HIGH. Default is LOW if nothing else is specified.
> 
> No. "retained until consumer changes the state" is promising more then
> is guaranteed.
> 
> From the explanations provided by Mark it is clear that this property
> is an artifact of the implementation in linux. I think we should document
> is as such. How about:
> 
> gpios-states : On operating systems, that don't support reading back gpio
>              values in output mode (most notably linux), this array
>              provides the state of GPIO pins set when requesting them
>              from the gpio controller.

That's good.

> Systems, that are capable of
>              preserving state when requesting the lines, are free to
>              ignore this property.

Are they ? I think there are systems which depend on preconfiguring the
GPIO according to this property.

> 0: LOW, 1: HIGH. Default is LOW if
>              nothing else is specified.
> 
> HTH,
> Harald
> 


-- 
Best regards,
Marek Vasut

Reply via email to