Re: [PATCH 2/2] dt-bindings: display: panel: Add Novatek NT35596S panel bindings

[Sam Ravnborg]

Hi Molly,

On Fri, Jul 08, 2022 at 10:18:24AM +0800, MollySophia wrote:
> Add documentation for "novatek,nt35596s" panel.

As a general note, we cannot apply a driver without the binding.
So this patch should be the first in the series.

Not a big deal, but it makes it easier on the committer later.

A few comments below.

	Sam

> 
> Signed-off-by: MollySophia <mollysophia379@xxxxxxxxx>
> ---
>  .../display/panel/novatek,nt35596s.yaml       | 88 +++++++++++++++++++
>  1 file changed, 88 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/panel/novatek,nt35596s.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/panel/novatek,nt35596s.yaml b/Documentation/devicetree/bindings/display/panel/novatek,nt35596s.yaml
> new file mode 100644
> index 000000000000..937b194a6f18
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/panel/novatek,nt35596s.yaml
> @@ -0,0 +1,88 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/panel/novatek,nt35596s.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Novatek NT35596S based DSI display Panels
> +
> +maintainers:
> +  - Molly Sophia <mollysophia379@xxxxxxxxx>
> +
> +description: |
> +  The nt35596s IC from Novatek is a generic DSI Panel IC used to drive dsi
> +  panels.
> +  Right now, support is added only for a JDI FHD+ LCD display panel with a
> +  resolution of 1080x2160. It is a video mode DSI panel.
> +
> +allOf:
> +  - $ref: panel-common.yaml#
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +          - jdi,fhd-nt35596s
> +      - const: novatek,nt35596s
> +    description: This indicates the panel manufacturer of the panel that is
> +      in turn using the NT35596S panel driver. This compatible string
> +      determines how the NT35596S panel driver is configured for the indicated
> +      panel. The novatek,nt35596s compatible shall always be provided as a fallback.
> +
> +  reset-gpios:
> +    maxItems: 1
> +    description: phandle of gpio for reset line - This should be 8mA, gpio
> +      can be configured using mux, pinctrl, pinctrl-names (active high)
reset-gpios is part of panel-common and there is no need to describe it
here. The description, which looks like a copy from another binding,
does not really tell anything that is specific for this HW.
So replace it with a
    reset-gpios: true
later in the binding would be better.

> +
> +  vddi0-supply:
> +    description: phandle of the regulator that provides the supply voltage
> +      Power IC supply
Please drop the "phandle of the" part. This is implicit and does not
provide any extra info on the actual HW.
This comments applies for all *-supply.

> +
> +  vddpos-supply:
> +    description: phandle of the positive boost supply regulator
> +
> +  vddneg-supply:
> +    description: phandle of the negative boost supply regulator
> +
> +  reg: true
> +  port: true
> +  backlight: true
> +
> +required:
> +  - compatible
> +  - reg
> +  - vddi0-supply
> +  - vddpos-supply
> +  - vddneg-supply
> +  - reset-gpios
> +  - port
> +
> +unevaluatedProperties: false

Use:
additionalProperties: false

This will catch if the DT file contains any properties that is not
mentioned here.
The use of unevaluatedProperties in the file you copied from looks
wrong.

> +
> +examples:
> +  - |+
No need for the + sign here.

> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    dsi0 {
dsi {


> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        panel@0 {
> +            compatible = "jdi,fhd-nt35596s", "novatek,nt35596s";
> +            reg = <0>;
> +            vddi0-supply = <&vreg_l14a_1p88>;
> +            vddpos-supply = <&lab>;
> +            vddneg-supply = <&ibb>;
> +
> +            backlight = <&pmi8998_wled>;
> +            reset-gpios = <&tlmm 6 GPIO_ACTIVE_HIGH>;
> +
> +            port {
> +                jdi_nt35596s_in_0: endpoint {
> +                    remote-endpoint = <&dsi0_out>;
> +                };
> +            };
> +        };
> +    };
> +
> +...
> -- 
> 2.37.0