Re: [PATCH RFC v3 3/6] dt-bindings: display: add Unisoc's dpu bindings

[Sam Ravnborg]

Hi Kevin.

On Fri, Feb 21, 2020 at 03:48:53PM +0800, Kevin Tang wrote:
> From: Kevin Tang <kevin.tang@xxxxxxxxxx>
> 
> DPU (Display Processor Unit) is the Display Controller for the Unisoc SoCs
> which transfers the image data from a video memory buffer to an internal
> LCD interface.
> 
> Cc: Orson Zhai <orsonzhai@xxxxxxxxx>
> Cc: Baolin Wang <baolin.wang@xxxxxxxxxx>
> Cc: Chunyan Zhang <zhang.lyra@xxxxxxxxx>
> Signed-off-by: Kevin Tang <kevin.tang@xxxxxxxxxx>
> ---
>  .../devicetree/bindings/display/sprd/dpu.yaml      | 85 ++++++++++++++++++++++
>  1 file changed, 85 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/sprd/dpu.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/sprd/dpu.yaml b/Documentation/devicetree/bindings/display/sprd/dpu.yaml
> new file mode 100644
> index 0000000..7695d94
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/sprd/dpu.yaml
> @@ -0,0 +1,85 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/sprd/dpu.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Unisoc SoC Display Processor Unit (DPU)
> +
> +maintainers:
> +  - David Airlie <airlied@xxxxxxxx>
> +  - Daniel Vetter <daniel@xxxxxxxx>
> +  - Rob Herring <robh+dt@xxxxxxxxxx>
> +  - Mark Rutland <mark.rutland@xxxxxxx>
> +
> +description: |
> +  DPU (Display Processor Unit) is the Display Controller for the Unisoc SoCs
> +  which transfers the image data from a video memory buffer to an internal
> +  LCD interface.
> +
> +properties:
> +  compatible:
> +    const: sprd,sharkl3-dpu
> +
> +  reg:
> +    maxItems: 1
> +    description:
> +      Physical base address and length of the DPU registers set
> +
> +  interrupts:
> +    maxItems: 1
> +    description:
> +      The interrupt signal from DPU
> +
> +  clocks:
> +    minItems: 2
Should this be maxItems: 2?
That would imply minItems: 2.


> +
> +  clock-names:
> +    items:
> +      - const: clk_src_128m
> +      - const: clk_src_384m
> +
> +  power-domains:
> +    description: A phandle to DPU power domain node.
> +
> +  iommus:
> +    description: A phandle to DPU iommu node.
> +
> +  port:
> +    type: object
> +    description:
> +      A port node with endpoint definitions as defined in
> +      Documentation/devicetree/bindings/media/video-interfaces.txt.
> +      That port should be the output endpoint, usually output to
> +      the associated DSI.
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clocks
> +  - clock-names
> +  - port
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/clock/sprd,sc9860-clk.h>
> +    dpu: dpu@0x63000000 {
> +          compatible = "sprd,sharkl3-dpu";
> +          reg = <0x0 0x63000000 0x0 0x1000>;
> +          interrupts = <GIC_SPI 46 IRQ_TYPE_LEVEL_HIGH>;
> +          clock-names = "clk_src_128m",
> +      	        "clk_src_384m";
> +
> +          clocks = <&pll CLK_TWPLL_128M>,
> +                <&pll CLK_TWPLL_384M>;
> +
> +          dpu_port: port {
> +                  dpu_out: endpoint {
> +                          remote-endpoint = <&dsi_in>;
> +                  };
> +          };
> +    };
Did this example pass dt_binding_check with no warnings?
I wonder how the reg property could avoid generating warnings as the
upper node do not have #address_cells, #node_cells

	Sam