Hi Rob,
On Fri, Jun 10, 2022 at 02:38:18PM -0600, Rob Herring wrote:
> 'arm,rtsm-display' is a panel for Arm, Ltd. virtual platforms (e.g. FVP).
> The binding has been in use for a long time, but was never documented.
>
> Some users and an example have a 'panel-dpi' compatible, but that's not
> needed without a 'panel-timing' node which none of the users have since
> commit 928faf5e3e8d ("arm64: dts: fvp: Remove panel timings"). The
> example does have a 'panel-timing' node, but it should not for the
> same reasons the node was removed in the dts files. So update the
> example in arm,pl11x.yaml to match the schema.
>
> Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
> Cc: Robin Murphy <robin.murphy@xxxxxxx>
> Cc: Andre Przywara <andre.przywara@xxxxxxx>
> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> .../bindings/display/arm,pl11x.yaml | 15 +-------------
> .../bindings/display/panel/panel-simple.yaml | 20 +++++++++++++------
> 2 files changed, 15 insertions(+), 20 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/display/arm,pl11x.yaml b/Documentation/devicetree/bindings/display/arm,pl11x.yaml
> index b545c6d20325..6cc9045e5c68 100644
> --- a/Documentation/devicetree/bindings/display/arm,pl11x.yaml
> +++ b/Documentation/devicetree/bindings/display/arm,pl11x.yaml
> @@ -159,25 +159,12 @@ examples:
> };
>
> panel {
> - compatible = "arm,rtsm-display", "panel-dpi";
> - power-supply = <&vcc_supply>;
> + compatible = "arm,rtsm-display";
>
> port {
> clcd_panel: endpoint {
> remote-endpoint = <&clcd_pads>;
> };
> };
> -
> - panel-timing {
> - clock-frequency = <25175000>;
> - hactive = <640>;
> - hback-porch = <40>;
> - hfront-porch = <24>;
> - hsync-len = <96>;
> - vactive = <480>;
> - vback-porch = <32>;
> - vfront-porch = <11>;
> - vsync-len = <2>;
> - };
> };
> ...
> diff --git a/Documentation/devicetree/bindings/display/panel/panel-simple.yaml b/Documentation/devicetree/bindings/display/panel/panel-simple.yaml
> index 21ba90c9fe33..97afd276c54a 100644
> --- a/Documentation/devicetree/bindings/display/panel/panel-simple.yaml
> +++ b/Documentation/devicetree/bindings/display/panel/panel-simple.yaml
> @@ -19,9 +19,6 @@ description: |
>
> If the panel is more advanced a dedicated binding file is required.
>
> -allOf:
> - - $ref: panel-common.yaml#
> -
> properties:
>
> compatible:
> @@ -35,6 +32,8 @@ properties:
> - ampire,am-480272h3tmqw-t01h
> # Ampire AM-800480R3TMQW-A1H 7.0" WVGA TFT LCD panel
> - ampire,am800480r3tmqwa1h
> + # Arm, Ltd. Virtual Platforms Display
> + - arm,rtsm-display
> # AU Optronics Corporation 10.1" WSVGA TFT LCD panel
> - auo,b101aw03
> # AU Optronics Corporation 10.1" WSVGA TFT LCD panel
> @@ -340,9 +339,18 @@ properties:
>
> additionalProperties: false
>
> -required:
> - - compatible
> - - power-supply
> +allOf:
> + - $ref: panel-common.yaml#
> + - if:
> + # Most 'simple' panels must have a single supply, but a virtual display does not
> + not:
> + properties:
> + compatible:
> + contains:
> + const: arm,rtsm-display
> + then:
> + required:
> + - power-supply
Sorry, but I do not like this change. The beauty of panel-simple is that
this is a collection of simple display with identical bindings because
the HW is more or less the same (in general - not in details like size
etc).
Any panels that requires more are pushed out to their own binding and
for arm,rtsm-display that would be better.
It is not this single exceptions that bothers me, it is the many
exceptions we will have in a few years from now.
Sam
