On Tue, Oct 27, 2026 at 07:24:08PM +0100, Krzysztof Kozlowski wrote:
> On 27/10/2026 19:18, Vishnu Saini wrote:
> >>>>> Declare 'backlight: true' so the property is explicitly allowed by the
> >>>>> schema.
> >>>>
> >>>> Why do you need to explicitly allow it? Since when?
> >>>>
> >>>> I see no benefit of this patch and commit msg does not explain me what
> >>>> that benefit would be.
> >>> It is required for below DLC panel, when enabling backlight using
> >>> gpio-backlight driver,
> >>
> >> How is it required? You did not really answer, so again:
> >>
> >> Why do you need to explicitly allow it?
> >>
> >> Answer starts "because ... " and you provide technical arguments, not
> >> wishes.
> > Because the DLC panel node references an external gpio-backlight device
> > through the
> > backlight property, but the current DLC binding does not allow this
> > property.
> > As a result, adding the backlight phandle to the panel node causes a
> > dtbs_check validation error.
>
> Thanks, but that's confusing or we looked at different source code,
> because to my eyes it clearly lists backlight already. Can you show me
> how can I reproduce the dtbs_check error?
You are right. I was looking at an older version of the binding which used
additionalProperties: false.
The current binding uses unevaluatedProperties: false and references
panel-common.yaml,
where the backlight property is already defined.
Therefore, I cannot reproduce the dtbs_check error with the current binding.
Thanks for pointing this out. This patch is redundent.
>
> Best regards,
> Krzysztof
