Re: [PATCH RFC 1/3] dt-bindings: input: elan: Introduce Elan eKTP1059 Touchpad

[Andreas Kemnade <andreas@kemnade.info>]

On Mon, 25 Aug 2025 17:40:56 +0100
Conor Dooley <conor@kernel.org> wrote:

> On Mon, Aug 25, 2025 at 12:07:28AM +0200, Andreas Kemnade wrote:
> > The Elan eKTP1059 Touchpad is seen in the Epson Moverio BT-200
> > attached via SPI. Add a binding for this chip. Little is known.
> > 
> > Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
> > ---
> >  .../devicetree/bindings/input/elan,ektp1059.yaml   | 45 ++++++++++++++++++++++
> >  1 file changed, 45 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/input/elan,ektp1059.yaml b/Documentation/devicetree/bindings/input/elan,ektp1059.yaml
> > new file mode 100644
> > index 000000000000..a10256a271e0
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/input/elan,ektp1059.yaml
> > @@ -0,0 +1,45 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/input/elan,ektp1059.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Elantech SPI Touchpad
> > +
> > +maintainers:
> > +  - Andreas Kemnade <andreas@kemnade.info>
> > +
> > +allOf:
> > +  - $ref: touchscreen/touchscreen.yaml#
> > +
> > +properties:
> > +  compatible:
> > +    const: elan,ektp1059
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - interrupts
> > +
> > +additionalProperties: false  
> 
> Shouldn't this be unevalutedProperties: false, since you want to make
> use of what's in touchscreen.yaml?
>
did not do too much thought about this yet. But am I allowed to use this
in a touchpad? BTW: who defines whether the chip is a touchpad? T*P* in
its part number might be a hint, the device where I am using it, uses it
as a touchpad. But who says it cannot be glued onto some screen?

Regards,
Andreas