Re: [PATCH 2/2] dt-bindings: touchscreen: ad7877: add bindings

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Thu, Aug 29, 2024 at 05:16:30PM +0100, Conor Dooley wrote:
> On Thu, Aug 29, 2024 at 12:19:36PM +0300, Antoniu Miclaus wrote:
> > Add device tree bindings for the ad7877 driver.
> > 
> > Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
> > ---
> >  .../input/touchscreen/adi,ad7877.yaml         | 58 +++++++++++++++++++
> >  1 file changed, 58 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/input/touchscreen/adi,ad7877.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/input/touchscreen/adi,ad7877.yaml b/Documentation/devicetree/bindings/input/touchscreen/adi,ad7877.yaml
> > new file mode 100644
> > index 000000000000..5fc5124c5999
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/input/touchscreen/adi,ad7877.yaml
> > @@ -0,0 +1,58 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/input/touchscreen/adi,ad7877.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Analog Devices AD7877 Touch Screen Controller
> > +
> > +maintainers:
> > +  - Antoniu Miclaus <antoniu.miclaus@analog.com>
> > +
> > +description: |
> > +  Analog Devices Touch Screen Controller
> > +  https://www.analog.com/media/en/technical-documentation/data-sheets/AD7877.pdf
> > +
> > +allOf:
> > +  - $ref: touchscreen.yaml#
> > +  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> 
> > +
> > +unevaluatedProperties: false
> 
> So, all of the properties in those two files are valid for this
> touchscreen controller?

No, the driver does not support transformations (swapping axes,
inverting, etc) but that is driver limitation, not property of the
hardware, which DT supposed to be, right?

Still I think we need to extend the driver to do that before adding DT
match tables and adding DT bindings (or maybe together with it).

The driver also need to have proper GPIO controller support instead of
having ad-hoc sysfs attributes, and converting in now before there are
mainline users would be a good time.

Thanks.

-- 
Dmitry