Re: [PATCH v8 2/2] dt-bindings: input: Goodix SPI HID Touchscreen

[Charles Wang <charles.goodix@gmail.com>]

Hi Krzysztof,
Thank you very much for your advice.

On Thu, Sep 26, 2024 at 02:32:05PM +0200, Krzysztof Kozlowski wrote:
> On 26/09/2024 11:57, Charles Wang wrote:
> >>>  1 file changed, 71 insertions(+)
> >>>  create mode 100644 Documentation/devicetree/bindings/input/goodix,gt7986u.yaml
> >>>
> >>> diff --git a/Documentation/devicetree/bindings/input/goodix,gt7986u.yaml b/Documentation/devicetree/bindings/input/goodix,gt7986u.yaml
> >>> new file mode 100644
> >>> index 000000000..849117639
> >>> --- /dev/null
> >>> +++ b/Documentation/devicetree/bindings/input/goodix,gt7986u.yaml
> >>> @@ -0,0 +1,71 @@
> >>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> >>> +%YAML 1.2
> >>> +---
> >>> +$id: http://devicetree.org/schemas/input/goodix,gt7986u.yaml#
> >>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> >>> +
> >>> +title: GOODIX GT7986U SPI HID Touchscreen
> >>> +
> >>> +maintainers:
> >>> +  - Charles Wang <charles.goodix@gmail.com>
> >>> +
> >>> +description: Supports the Goodix GT7986U touchscreen.
> >>> +  This touch controller reports data packaged according to the HID protocol,
> >>> +  but is incompatible with Microsoft's HID-over-SPI protocol.
> >>> +
> >>> +allOf:
> >>> +  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> >>> +
> >>> +properties:
> >>> +  compatible:
> >>> +    enum:
> >>> +      - goodix,gt7986u-spi
> >>
> >> NAK, you duplicate again the binding. You cannot have bus-flavors.
> >> Device is the same.
> >>
> > 
> > Could you provide some suggestions regarding this issue?
> 
> What is exactly the question or problem? There is a binding for this
> device. Extend it with SPI parts, e.g.
> https://elixir.bootlin.com/linux/v6.4-rc7/source/Documentation/devicetree/bindings/iio/accel/adi,adxl313.yaml#L22
> 

This seems a little different from the adxl313.yaml.

The issue we're encountering involves the chip model gt7986u,
which supports both I2C and SPI interfaces. For the I2C interface
(using the HID-over-I2C driver), it has already been declared in
the goodix,gt7375p.yaml file as follows:

i2c {
  #address-cells = <1>;
  #size-cells = <0>;

  ap_ts: touchscreen@5d {
    compatible = "goodix,gt7986u";
  }
}

Currently, our design requires utilizing the SPI interface with
a custom SPI driver. However, the declarations within the binding
file have led to conflicts, as shown here:

spi {
  #address-cells = <1>;
  #size-cells = <0>;

  touchscreen@0 {
    compatible = "goodix,gt7986u";
  }
}

Should I consider merging both YAML files into a single one to fix this?

Best regards!
Charles