Re: [PATCH v3 2/7] dt-bindings: mdf: ti,j721e-syscon.yaml: Add J721e system controller

[Rob Herring]

On Fri, May 08, 2020 at 11:29:32AM +0300, Roger Quadros wrote:
> Add DT binding schema for J721e system controller.
> 
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> ---
>  .../bindings/mfd/ti,j721e-syscon.yaml         | 69 +++++++++++++++++++
>  1 file changed, 69 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/ti,j721e-syscon.yaml

Use the compatible string for filename.

> 
> diff --git a/Documentation/devicetree/bindings/mfd/ti,j721e-syscon.yaml b/Documentation/devicetree/bindings/mfd/ti,j721e-syscon.yaml
> new file mode 100644
> index 000000000000..e832fb43f884
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/ti,j721e-syscon.yaml
> @@ -0,0 +1,69 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com/
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/ti,j721e-syscon.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: TI J721e System Controller Registers R/W Device Tree Bindings
> +
> +description: |
> +  This represents the Control Module registers (CTRL_MMR0) on the SoC.
> +  System controller node represents a register region containing a set
> +  of miscellaneous registers. The registers are not cohesive enough to
> +  represent as any specific type of device. The typical use-case is
> +  for some other node's driver, or platform-specific code, to acquire
> +  a reference to the syscon node (e.g. by phandle, node path, or
> +  search using a specific compatible value), interrogate the node (or
> +  associated OS driver) to determine the location of the registers,
> +  and access the registers directly.
> +
> +maintainers:
> +  - Kishon Vijay Abraham I <kishon@xxxxxx>
> +  - Roger Quadros <rogerq@xxxxxx
> +
> +allOf:
> +  - $ref: "syscon.yaml#"

Drop this as it is not needed.

> +
> +properties:
> +  compatible:
> +    anyOf:
> +      - items:
> +        - enum:
> +          - ti,j721e-system-controller
> +
> +        - const: syscon

What about simple-mfd?

> +
> +      - contains:
> +          const: syscon
> +        additionalItems: true

Should be dropped.

You are going to need a 'select' entry or this will match on any syscon 
or simple-mfd node:

select:
  properties:
    compatible:
      contains:
        const: ti,j721e-system-controller
  required:
    - compatible


> +
> +# Optional children
> +
> +  "^serdes-ln-ctrl@[0-9a-f]+$":
> +    type: object
> +    description: |
> +      This is the SERDES lane control mux. It should follow the bindings
> +      specified in
> +      Documentation/devicetree/bindings/mux/reg-mux.txt

Really this should reference a 'reg-mux' schema, but fine for now. Bonus 
points if you do convert reg-mux.txt though. 

> +
> +required:
> +  - compatible
> +  - reg
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    scm_conf: scm-conf@100000 {
> +        compatible = "ti,j721e-system-controller", "syscon", "simple-mfd";
> +        reg = <0x00100000 0x1c000>;
> +        #address-cells = <1>;
> +        #size-cells = <1>;

These aren't documented and you need 'ranges' for the child address to 
be translatable.

> +
> +        serdes_ln_ctrl: serdes-ln-ctrl@4080 {
> +            compatible = "mmio-mux";
> +            reg = <0x00004080 0x50>;
> +        };
> +    };
> +...
> -- 
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