Re: [PATCH v1 1/8] dt-bindings: display: panel: properly document LG LD070WX3 panel

[Doug Anderson]

Hi,

On Mon, Sep 29, 2025 at 7:25 AM Svyatoslav Ryhel <clamor95@xxxxxxxxx> wrote:
>
> LG LD070WX3-SL01 was mistakenly documented as a simple DSI panel, which it
> clearly is not. Address this by adding the proper schema for this panel.
>
> Signed-off-by: Svyatoslav Ryhel <clamor95@xxxxxxxxx>
> ---
>  .../bindings/display/panel/lg,ld070wx3.yaml   | 60 +++++++++++++++++++
>  .../display/panel/panel-simple-dsi.yaml       |  2 -
>  2 files changed, 60 insertions(+), 2 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/display/panel/lg,ld070wx3.yaml
>
> diff --git a/Documentation/devicetree/bindings/display/panel/lg,ld070wx3.yaml b/Documentation/devicetree/bindings/display/panel/lg,ld070wx3.yaml
> new file mode 100644
> index 000000000000..0a82cf311452
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/panel/lg,ld070wx3.yaml
> @@ -0,0 +1,60 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/panel/lg,ld070wx3.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: LG Corporation 7" WXGA TFT LCD panel
> +
> +maintainers:
> +  - Svyatoslav Ryhel <clamor95@xxxxxxxxx>
> +
> +allOf:
> +  - $ref: panel-common.yaml#
> +
> +properties:
> +  compatible:
> +    items:
> +      - const: lg,ld070wx3-sl01
> +
> +  reg:
> +    maxItems: 1
> +
> +  vdd-supply: true
> +  vcc-supply: true
> +
> +  backlight: true
> +  port: true
> +
> +required:
> +  - compatible
> +  - vdd-supply
> +  - vcc-supply

I suspect you'll get a NAK here because you're not preserving backward
compatibility for existing device trees. While there can sometimes be
reasons to do that, you'd need to provide a very strong justification.


It seems like instead of breaking compatibility you could just have
two supplies:

* power-supply - The name for the "dvdd" supply.
* avdd-supply - The name for the "avdd" supply.

...and then you make both of them not "required". Maybe you'd add some
documentation saying that things might not work 100% correctly if they
weren't provided but that old device trees didn't specify them?