Re: [PATCH v2 2/2] dt-bindings: google,cros-ec-keyb: add use-fn-overlay prop

[Fabio Baltieri]

On Mon, Dec 29, 2025 at 03:59:44PM +0100, Krzysztof Kozlowski wrote:
> On 29/12/2025 14:33, Fabio Baltieri wrote:
> > On Mon, Dec 29, 2025 at 01:49:05PM +0100, Krzysztof Kozlowski wrote:
> >> On 27/12/2025 16:48, Fabio Baltieri wrote:
> >>> On Sat, Dec 27, 2025 at 01:44:26PM +0100, Krzysztof Kozlowski wrote:
> >>>>> diff --git a/Documentation/devicetree/bindings/input/google,cros-ec-keyb.yaml b/Documentation/devicetree/bindings/input/google,cros-ec-keyb.yaml
> >>>>> index fefaaf46a240..437575cdf352 100644
> >>>>> --- a/Documentation/devicetree/bindings/input/google,cros-ec-keyb.yaml
> >>>>> +++ b/Documentation/devicetree/bindings/input/google,cros-ec-keyb.yaml
> >>>>> @@ -44,6 +44,14 @@ properties:
> >>>>>        where the lower 16 bits are reserved. This property is specified only
> >>>>>        when the keyboard has a custom design for the top row keys.
> >>>>>  
> >>>>> +  google,use-fn-overlay:
> >>>>> +    description: |
> >>>>> +      Use a function key overlay. This allows defining an extra set of codes
> >>>>
> >>>> What is a function key overlay? Overlays are DT term and therefore are
> >>>> not suitable for bindings.
> >>>
> >>> Ok, guess I can rename it to `use-fn-key` or `use-fn-layer`, open to
> >>> suggestions really.
> >>
> >> Use as Linux should use? Then it's software, so not suitable for DT.
> > 
> > Sorry I'm not sure how I understand the comment, this describes how the
> > driver handles a keyboard with Fn keys, the codes are defined in the DT
> 
> Exactly. The purpose of DT is not to describe how driver should handle
> anything.
> 
> See also DTS101 from this year's ELCE.

Sure so I guess this falls into the "describe the hardware feature"
category, so is the suggestion to rename it to something like
"has-fn-key"? That would be the hardware feature.