Re: [PATCH v8 1/2] dt-bindings: input: touchscreen: add hynitron cst816x

[Krzysztof Kozlowski <krzk@kernel.org>]

On 29/06/2025 18:25, Oleh Kuzhylnyi wrote:
> Add documentation for Hynitron CST816x series touchscreen bindings.
> 
> Signed-off-by: Oleh Kuzhylnyi <kuzhylol@gmail.com>
> ---
> Changes in v8:
>  - Use linux,keycodes to map touch gestures to key events
>  - Refactore binding properties based on feedback from Jeff LaBundy
>    and Krzysztof Kozlowski to align with official documentation

This is vague. Anything can be "refactor". What changed specifically?

b4 diff shows no changes.


> 
> Changes in v7:
>  - Introduce the gestures field along with its sub-fields
>  - Make reset-gpio property optional
>  - Extend main description
>  - Remove "touchscreen" reference
> 
> Changes in v6:
>  - Fix minor tweak adviced by Krzysztof:
>  - Move additionalProperties field after required
> 
> Changes in v5:
>  - No code changes
> 
> Changes in v4:
>  - Add Conor's Dooley "Reviewed-by" tag
> 
> Changes in v3:
>  - Rename filename to hynitron,cst816s.yaml
>  - Update description with display details
> 
> Changes in v2:
>  - Apply pin definitions and DT headers
>  - Use generic name for DT node
>  - Drop status field
> 
>  .../input/touchscreen/hynitron,cst816x.yaml   | 82 +++++++++++++++++++
>  1 file changed, 82 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/input/touchscreen/hynitron,cst816x.yaml
> 
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/hynitron,cst816x.yaml b/Documentation/devicetree/bindings/input/touchscreen/hynitron,cst816x.yaml
> new file mode 100644
> index 000000000000..0d358463d7f8
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/touchscreen/hynitron,cst816x.yaml
> @@ -0,0 +1,82 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/input/touchscreen/hynitron,cst816x.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Hynitron CST816x Series Capacitive Touch controller
> +
> +maintainers:
> +  - Oleh Kuzhylnyi <kuzhylol@gmail.com>
> +
> +description: |
> +  Bindings for CST816x high performance self-capacitance touch chip series
> +  with single point gesture and real two-point operation.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - hynitron,cst816s
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  reset-gpios:
> +    maxItems: 1
> +
> +  linux,keycodes:
> +    minItems: 1
> +    maxItems: 16
> +    description: |
> +      Specifies the numeric keycodes associated with each available gesture in
> +      the following order (enter 0 for unused and reserved gestures):
> +      0: Touch
> +      1: Swipe up
> +      2: Swipe down
> +      3: Swipe left
> +      4: Swipe right
> +      5-11: Reserved
> +      12: Long press
> +      13-15: Reserved

Fields like "reserved" makes no sense. If this is reserved, why would it
be put into the DTS?

No, just list the items with description:
minItems: 1
items:
  - description: Touch gesture (although what is a touch gesture? This
is just a touch....)
  - description: ...


> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts


Where is (or why there is no) the ref to touchscreen.yaml?

> +
> +additionalProperties: false

And this not unevaluatedProperties then?

> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/input/linux-event-codes.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    i2c {
> +          #address-cells = <1>;
> +          #size-cells = <0>;

Messed indentation.

> +          touchscreen@15 {
> +              compatible = "hynitron,cst816s";
> +              reg = <0x15>;
> +              interrupt-parent = <&gpio0>;
> +              interrupts = <4 IRQ_TYPE_EDGE_RISING>;
> +              reset-gpios = <&gpio 17 GPIO_ACTIVE_LOW>;
> +              linux,keycodes = <BTN_TOUCH>,




Best regards,
Krzysztof