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

[Conor Dooley <conor@kernel.org>]

[-- Attachment #1: Type: text/plain, Size: 2705 bytes --]

On Thu, Aug 29, 2024 at 11:07:45AM -0700, Dmitry Torokhov wrote:
> 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?

Yeah, I'm only interested in whether or not the properties are actually
applicable to the hardware. In particular, if there are properties in
spi-peripheral-props required for functionality (eg active high cs) I
would like to see them required.

> 
> 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.

Do you mean that this device is a provider of GPIOs? If so, then
absolutely I would want to see gpio controller properties in the binding
here before adding support.


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]