Re: [PATCH v9 2/2] dt-bindings: msm/dp: Add bindings of MSM DisplayPort controller

[Stephen Boyd <swboyd@xxxxxxxxxxxx>]

Quoting Krishna Manikandan (2020-12-10 23:09:45)
> Changes in v10:
> - Change title of this patch as it does not contain PLL bindings anymore
> - Remove redundant properties
> - Remove use of IRQ flag
> - Fix ports property
> 
> Previous Change log:
> https://lkml.kernel.org/lkml/1597066683-6044-2-git-send-email-mkrishn@xxxxxxxxxxxxxx/

Why can't that be put in here instead of making me click the link?

> diff --git a/Documentation/devicetree/bindings/display/msm/dp-controller.yaml b/Documentation/devicetree/bindings/display/msm/dp-controller.yaml
> new file mode 100644
> index 0000000..bc80632
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/msm/dp-controller.yaml
> @@ -0,0 +1,120 @@
> +# SPDX-License-Identifier: (GPL-2.0-only  OR BSD-2-Clause)

Why two spaces between 'only and 'OR'?

> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/msm/dp-controller.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: MSM Display Port Controller.

Drop the full-stop?

> +
> +maintainers:
> +  - Chandan Uddaraju <chandanu@xxxxxxxxxxxxxx>
> +  - Vara Reddy <varar@xxxxxxxxxxxxxx>
> +  - Tanmay Shah <tanmay@xxxxxxxxxxxxxx>
> +
> +description: |
> +  Device tree bindings for DisplayPort host controller for MSM targets
> +  that are compatible with VESA DisplayPort interface specification.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - qcom,sc7180-dp
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  clocks:
> +    items:
> +      - description: AHB clock to enable register access
> +      - description: Display Port AUX clock
> +      - description: Display Port Link clock
> +      - description: Link interface clock between DP and PHY
> +      - description: Display Port Pixel clock
> +
> +  clock-names:
> +    items:
> +      - const: core_iface
> +      - const: core_aux
> +      - const: ctrl_link
> +      - const: ctrl_link_iface
> +      - const: stream_pixel

There should be a dp-phy too, so 'phy' and 'phy-names' property. I see a
'power-domains' property downstream, so please add that too. And also
'#sound-dai-cells".

> +
> +  ports:
> +    type: object
> +    description: |
> +      A ports node with endpoint definitions as defined in
> +      Documentation/devicetree/bindings/media/video-interfaces.txt.
> +    properties:
> +      "#address-cells":
> +        const: 1
> +
> +      "#size-cells":
> +        const: 0
> +
> +      port@0:
> +        type: object
> +        description: Input endpoint of the controller.
> +
> +      port@1:
> +        type: object
> +        description: Output endpoint of the controller.

This should have a required section too, and state that all the above
properties are required.

> +
> +    additionalProperties: false
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clocks
> +  - clock-names
> +  - ports
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/clock/qcom,dispcc-sc7180.h>
> +
> +    mdss: mdss {

Can drop the label. Also this node name is bad! Should be
'subsystem@<reg>' I guess? And then the reg can just be the first
address in a reg property that is remapped for the children nodes.

> +      #address-cells = <2>;
> +      #size-cells = <2>;
> +      interrupt-controller;
> +
> +      msm_dp: displayport-controller@ae90000 {

Can drop the label.

> +        compatible = "qcom,sc7180-dp";
> +        reg = <0 0xae90000 0 0x1400>;
> +        interrupt-parent = <&mdss>;
> +        interrupts = <12>;
> +        clocks = <&dispcc DISP_CC_MDSS_AHB_CLK>,
> +                 <&dispcc DISP_CC_MDSS_DP_AUX_CLK>,
> +                 <&dispcc DISP_CC_MDSS_DP_LINK_CLK>,
> +                 <&dispcc DISP_CC_MDSS_DP_LINK_INTF_CLK>,
> +                 <&dispcc DISP_CC_MDSS_DP_PIXEL_CLK>;
> +        clock-names = "core_iface", "core_aux",
> +                      "ctrl_link",
> +                      "ctrl_link_iface", "stream_pixel";
> +
> +        ports {
> +            #address-cells = <1>;
> +            #size-cells = <0>;
> +
> +            port@0 {
> +                reg = <0>;
> +                dp_in: endpoint {

Can drop the label.

> +                    remote-endpoint = <&dpu_intf0_out>;
> +                };
> +            };
> +
> +            port@1 {
> +                reg = <1>;
> +                dp_out: endpoint {

Can drop the label and show some remote-endpoint connection?

> +                };
> +            };
> +        };
> +      };
> +    };
> +...