[PATCH v8 1/2] dt-bindings: drm/bridge: anx7625: MIPI to DP transmitter binding

[Sam Ravnborg]

Hi Xin Ji

On Mon, Apr 27, 2020 at 02:17:46PM +0800, Xin Ji wrote:
> The ANX7625 is an ultra-low power 4K Mobile HD Transmitter designed
> for portable device. It converts MIPI to DisplayPort 1.3 4K.

Thanks for providing this binding.
When you re-submit please also send to devicetree at vger.kernel.org.

Running the binding through dt_binding_check gives me:

/home/sam/drm/linux.git/Documentation/devicetree/bindings/display/bridge/anx7625.yaml: ignoring, error in schema:
warning: no schema found in file: /home/sam/drm/linux.git/Documentation/devicetree/bindings/display/bridge/anx7625.yaml
make[2]: *** [/home/sam/drm/linux.git/Documentation/devicetree/bindings/Makefile:42: Documentation/devicetree/bindings/processed-schema.yaml] Error 255
make[2]: *** Waiting for unfinished jobs....
/home/sam/drm/linux.git/Documentation/devicetree/bindings/display/bridge/anx7625.yaml: Additional properties are not allowed ('example' was unexpected)
/home/sam/drm/linux.git/Documentation/devicetree/bindings/display/bridge/anx7625.yaml: Additional properties are not allowed ('example' was unexpected)

See writing-schemas.rst for instruction installing tools etc.

> 
> You can add support to your board with binding.
> 
> Example:
> 	anx7625_bridge: encoder at 58 {
> 		compatible = "analogix,anx7625";
> 		reg = <0x58>;
> 		status = "okay";
> 		panel-flags = <1>;
> 		enable-gpios = <&pio 45 GPIO_ACTIVE_HIGH>;
> 		reset-gpios = <&pio 73 GPIO_ACTIVE_HIGH>;
> 		#address-cells = <1>;
> 		#size-cells = <0>;
> 
> 		port at 0 {
> 		  reg = <0>;
> 		  anx_1_in: endpoint {
> 		    remote-endpoint = <&mipi_dsi>;
> 		  };
> 		};
> 
> 		port at 2 {
> 		  reg = <2>;
> 		  anx_1_out: endpoint {
> 		    remote-endpoint = <&panel_in>;
> 		  };
> 		};
> 	};
> 
> Signed-off-by: Xin Ji <xji at analogixsemi.com>
> ---
>  .../bindings/display/bridge/anx7625.yaml           | 91 ++++++++++++++++++++++
>  1 file changed, 91 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/bridge/anx7625.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/anx7625.yaml b/Documentation/devicetree/bindings/display/bridge/anx7625.yaml
> new file mode 100644
> index 0000000..1149ebb
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/anx7625.yaml

Name the file "analogix,anx7625.yaml".
(We should rename anx6345.yaml, so others do not omit the company name)

> @@ -0,0 +1,91 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +# Copyright 2019 Analogix Semiconductor, Inc.
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/display/bridge/anx7625.yaml#"
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> +
> +title: Analogix ANX7625 SlimPort (4K Mobile HD Transmitter)
> +
> +maintainers:
> +  - Xin Ji <xji at analogixsemi.com>
> +
> +description: |
> +  The ANX7625 is an ultra-low power 4K Mobile HD Transmitter
> +  designed for portable devices.
> +
> +properties:
> +  "#address-cells": true
> +  "#size-cells": true
> +
> +  compatible:
> +    items:
> +      - const: analogix,anx7625
> +
> +  reg:
> +    maxItems: 1
> +
> +  panel-flags:
> +    description: indicate the panel is internal or external.
> +    maxItems: 1
This property hint at something needs to be modelled in a different way.
I do not recall other bindings need similar info.

> +
> +  interrupts:
> +    maxItems: 1
A description would be nice.

> +
> +  enable-gpios:
> +    description: used for power on chip control, POWER_EN pin D2.
> +    maxItems: 1
> +
> +  reset-gpios:
> +    description: used for reset chip control, RESET_N pin B7.
> +    maxItems: 1
> +
> +  port at 0:
> +    type: object
> +    description:
> +      A port node pointing to MIPI DSI host port node.
> +
> +  port at 1:
> +    type: object
> +    description:
> +      A port node pointing to MIPI DPI host port node.
Maybe explain how it differs from port at 0 and why it is optional.

> +
> +  port at 2:
> +    type: object
> +    description:
> +      A port node pointing to panel port node.
Unless there is a good reason not to then please use a ports node, like
you see in almost (all?) other bridge bindings.

> +
> +required:
> +  - "#address-cells"
> +  - "#size-cells"
> +  - compatible
> +  - reg
> +  - port at 0
> +  - port at 2

additionalProperties: false??


> +
> +example:
It must be named "examples:" - this is what dt_binding_check complains
about.

> +  - |
> +    anx7625_bridge: encoder at 58 {
> +        compatible = "analogix,anx7625";
> +        reg = <0x58>;
> +        status = "okay";
No status in examples.

> +        panel-flags = <1>;
> +        enable-gpios = <&pio 45 GPIO_ACTIVE_HIGH>;
You need to include a header file to pull in GPIO_ACTIVE_HIGH - see what
other bindings do.
> +        reset-gpios = <&pio 73 GPIO_ACTIVE_HIGH>;
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        port at 0 {
> +          reg = <0>;
Be consistent with indent. My personal preference is 4 spaces.

> +          anx_1_in: endpoint {
> +            remote-endpoint = <&mipi_dsi>;
> +          };
> +        };
> +
> +        port at 2 {
> +          reg = <2>;
> +          anx_1_out: endpoint {
> +            remote-endpoint = <&panel_in>;
> +          };
> +        };
> +    };

Lot's of small comments. But if this is your first binding then this is
expected.
Looks forward for v2.

	Sam