Re: [PATCH v3 1/2] dt-bindings: input: Goodix GT7986U SPI HID Touchscreen

[Charles Wang]

Hi Rob,

On Fri, Nov 08, 2024 at 10:10:00AM -0600, Rob Herring wrote:
> On Fri, Nov 08, 2024 at 08:03:10PM +0800, Charles Wang wrote:
> > The Goodix GT7986U touch controller report touch data according to the
> > HID protocol through the SPI bus. However, it is incompatible with
> > Microsoft's HID-over-SPI protocol.
> > 
> > NOTE: these bindings are distinct from the bindings used with the
> > GT7986U when the chip is running I2C firmware. For some background,
> > see discussion on the mailing lists in the thread:
> > 
> > https://lore.kernel.org/r/20241018020815.3098263-2-charles.goodix@xxxxxxxxx
> > 
> > Signed-off-by: Charles Wang <charles.goodix@xxxxxxxxx>
> > ---
> >  .../bindings/input/goodix,gt7986u-spifw.yaml  | 75 +++++++++++++++++++
> >  1 file changed, 75 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/input/goodix,gt7986u-spifw.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/input/goodix,gt7986u-spifw.yaml b/Documentation/devicetree/bindings/input/goodix,gt7986u-spifw.yaml
> > new file mode 100644
> > index 000000000..8105b9ce2
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/input/goodix,gt7986u-spifw.yaml
> > @@ -0,0 +1,75 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/input/goodix,gt7986u-spifw.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Goodix GT7986U SPI HID Touchscreen
> > +
> > +maintainers:
> > +  - Charles Wang <charles.goodix@xxxxxxxxx>
> > +
> > +description: Supports the Goodix GT7986U touchscreen.
> 
> Move to next line.
> 

Ack,

>
> > +  This touch controller reports data packaged according to the HID protocol
> > +  over the SPI bus, but it is incompatible with Microsoft's HID-over-SPI protocol.
> > +
> 
> If you want to maintain paragraphs you need '>' or '|' after 
> 'description:'. IIRC, it has to be '|' due to the "NOTE: " here:
> 

Ack, using '|' works.

Best regars,
Charles

>
> > +  NOTE: these bindings are distinct from the bindings used with the
> > +  GT7986U when the chip is running I2C firmware. This is because there's
> > +  not a single device that talks over both I2C and SPI but rather
> > +  distinct touchscreens that happen to be built with the same ASIC but
> > +  that are distinct products running distinct firmware.
> > +
> > +allOf:
> > +  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - goodix,gt7986u-spifw
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  reset-gpios:
> > +    maxItems: 1
> > +
> > +  goodix,hid-report-addr:
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    description:
> > +      The register address for retrieving HID report data.
> > +
> > +  spi-max-frequency: true
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - interrupts
> > +  - reset-gpios
> > +  - goodix,hid-report-addr
> > +
> > +unevaluatedProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/interrupt-controller/irq.h>
> > +    #include <dt-bindings/gpio/gpio.h>
> > +
> > +    spi {
> > +      #address-cells = <1>;
> > +      #size-cells = <0>;
> > +
> > +      touchscreen@0 {
> > +        compatible = "goodix,gt7986u-spifw";
> > +        reg = <0>;
> > +        interrupt-parent = <&gpio>;
> > +        interrupts = <25 IRQ_TYPE_LEVEL_LOW>;
> > +        reset-gpios = <&gpio1 1 GPIO_ACTIVE_LOW>;
> > +        spi-max-frequency = <10000000>;
> > +        goodix,hid-report-addr = <0x22c8c>;
> > +      };
> > +    };
> > +
> > +...
> > -- 
> > 2.43.0
> >