Re: [PATCH v2 01/16] arm64: dts: qcom: x1-crd: Mark the EC reset gpio as reserved

[Abel Vesa]

On 26-09-03 11:37:09, Konrad Dybcio wrote:
> On 9/3/26 11:29 AM, Abel Vesa wrote:
> > On 26-09-03 11:16:20, Konrad Dybcio wrote:
> >> On 9/3/26 10:34 AM, Abel Vesa wrote:
> >>> On 26-09-02 17:53:23, Konrad Dybcio wrote:
> >>>> On 9/1/26 10:06 AM, Abel Vesa wrote:
> >>>>> GPIO 65 from TLMM is used by the embedded controller as its reset line.
> >>>>>
> >>>>> On some devices, toggling the embedded controller reset line makes the
> >>>>> device not power up at all, unless the battery is unplugged.
> >>>>
> >>>> Have you confirmed that behavior on the CRD?
> >>>
> >>> Toggling it does nothing observable.
> >>>
> >>> However, the documentation says this GPIO is actually tied to EC reset.
> >>>
> >>> I still think we should reserve it, just to be safe.
> >>>
> >>> What do you think?
> >>
> >> I believe that contradicts the reasoning you gave in the commit
> >> message then..
> > 
> > Yep, will rephrase it for this platform as:
> > 
> > While toggling it from linux doesn't seem to have any observable impact,
> > since documentation does confrm it is connected to EC reset, lets reserve
> > it just to be on the safe side.
> 
> Have you toggled the pin into the correct polarity? The EC FW seems not
> to be handling that pin at all, so I'm guessing it should be just a dumb
> chip reset

Hm. Good catch. It is actually active high, and it renders keyboard
broken after EC reset. Also fans start spinning full speed during EC
reset.