Re: [RESEND PATCH v2 3/3] ARM: dts: imx28-cfa10036: Fix the reset gpio signal polarity
From: VokÃÄ Michal
Date: Tue Oct 09 2018 - 09:18:32 EST
On 9.10.2018 14:36, Fabio Estevam wrote:
> Hi Michal,
>
> On Tue, Oct 9, 2018 at 5:30 AM VokÃÄ Michal <Michal.Vokac@xxxxxxxxx> wrote:
>
>> Sorry for the inconvenience :( Lesson learned..
>>
>> So in other words (no offense): broken drivers need to stay broken because
>> users may already get used to the broken behavior?
>
> In order to keep the old dtb's working you could introduce a new
> property (like reset-gpio-active-low, for example).
>
> Then the driver behavior can be made untouched for the old dtb's and
> only new dtb's with this new property would have the correct GPIO
> reset behavior.
Thank you very much Fabio!
I saw these xxx-active-low/high properties in many device tree
sources wondering why the heck people use them when they could
use GPIO_ACTIVE_LOW/HIGH. And this is the explanation.
And I feel like an idiot once again: git grep -l "reset-active-low"
first hit is:
Documentation/devicetree/bindings/display/ssd1307fb.txt
Oooops.
The weird thing is that usage of reset-active-low is documented
in the example but it is not implemented.
So the patch no.2 should be reverted and patch no.3 not applied at all.
I will prepare a new patch utilizing the reset-active-low property.
Again, sorry for the troubles and thank you for your comments.
Michal