Re: [PATCH v5 2/4] dt-bindings: input: Add Cypress TT2100 touchscreen controller

[Rob Herring <robh@kernel.org>]

On Sun, Jan 09, 2022 at 09:53:29PM +1000, Alistair Francis wrote:
> From: Mylène Josserand <mylene.josserand@free-electrons.com>
> 
> Add the Cypress TrueTouch Generation 5 touchscreen device tree bindings
> documentation. It can use I2C or SPI bus.
> This touchscreen can handle some defined zone that are designed and
> sent as button. To be able to customize the keycode sent, the
> "linux,code" property in a "button" sub-node can be used.
> 
> Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com>
> Signed-off-by: Alistair Francis <alistair@alistair23.me>
> ---
>  .../input/touchscreen/cypress,tt21000.yaml    | 92 +++++++++++++++++++
>  1 file changed, 92 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/input/touchscreen/cypress,tt21000.yaml
> 
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/cypress,tt21000.yaml b/Documentation/devicetree/bindings/input/touchscreen/cypress,tt21000.yaml
> new file mode 100644
> index 000000000000..acd2d9389f8c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/touchscreen/cypress,tt21000.yaml
> @@ -0,0 +1,92 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/input/touchscreen/cypress,tt21000.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Cypress TT2100 touchscreen controller
> +
> +description: The Cypress TT2100 series (also known as "CYTTSP5" after
> +  the marketing name Cypress TrueTouch Standard Product series 5).
> +
> +maintainers:
> +  - Alistair Francis <alistair@alistair23.me>
> +
> +allOf:
> +  - $ref: touchscreen.yaml#
> +
> +properties:
> +  compatible:
> +    const: cypress,tt21000
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  vdd-supply:
> +    description: Regulator for voltage.
> +
> +  reset-gpios:
> +    maxItems: 1
> +
> +  linux,code:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: EV_ABS specific event code generated by the axis.
> +
> +patternProperties:
> +  "^button-[0-9]+$":

Where does the numbering come from? I assume it correlates to something 
in the h/w. If so, I think you should use 'reg' and a unit-address here. 
Generally, we don't want the node names to be important (i.e. used by 
the OS).

> +    type: object
> +    properties:
> +      linux,code:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description: Keycode to emit
> +
> +    required:
> +      - linux,code
> +
> +    additionalProperties: false
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - vdd-supply
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/input/linux-event-codes.h>
> +
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        touchscreen@24 {
> +            compatible = "cypress,tt21000";
> +            reg = <0x24>;
> +            pinctrl-names = "default";
> +            pinctrl-0 = <&tp_reset_ds203>;
> +            interrupt-parent = <&pio>;
> +            interrupts = <1 5 IRQ_TYPE_LEVEL_LOW>;
> +            reset-gpios = <&pio 7 1 GPIO_ACTIVE_LOW>;
> +            vdd-supply = <&reg_touch>;
> +
> +            button-0 {
> +                linux,code = <KEY_HOMEPAGE>;
> +            };
> +
> +            button-1 {
> +                linux,code = <KEY_MENU>;
> +            };
> +
> +            button-2 {
> +                linux,code = <KEY_BACK>;
> +            };
> +        };
> +    };
> +...
> -- 
> 2.31.1
> 
>