Re: [PATCH v4 04/17] dt-bindings: fsi: p9-occ: Convert to json-schema

[Krzysztof Kozlowski <krzk@xxxxxxxxxx>]

On 29/04/2024 23:01, Eddie James wrote:
> Conver to json-schema for the OCC documentation. Also document the fact
> that the OCC "bridge" device will often have the hwmon node as a
> child.
> 
> Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx>
> ---
> Changes since v3:
>  - Move required below other properties
>  - Drop "occ-" in child node
>  - Drop hwmon unit address
>  - Complete example
>  - Change commit message to match similar commits
> 
>  .../devicetree/bindings/fsi/ibm,p9-occ.txt    | 16 --------
>  .../devicetree/bindings/fsi/ibm,p9-occ.yaml   | 41 +++++++++++++++++++
>  2 files changed, 41 insertions(+), 16 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/fsi/ibm,p9-occ.txt
>  create mode 100644 Documentation/devicetree/bindings/fsi/ibm,p9-occ.yaml
> 
> diff --git a/Documentation/devicetree/bindings/fsi/ibm,p9-occ.txt b/Documentation/devicetree/bindings/fsi/ibm,p9-occ.txt
> deleted file mode 100644
> index e73358075a90..000000000000
> --- a/Documentation/devicetree/bindings/fsi/ibm,p9-occ.txt
> +++ /dev/null
> @@ -1,16 +0,0 @@
> -Device-tree bindings for FSI-attached POWER9/POWER10 On-Chip Controller (OCC)
> ------------------------------------------------------------------------------
> -
> -This is the binding for the P9 or P10 On-Chip Controller accessed over FSI from
> -a service processor. See fsi.txt for details on bindings for FSI slave and CFAM
> -nodes. The OCC is not an FSI slave device itself, rather it is accessed
> -through the SBE FIFO.
> -
> -Required properties:
> - - compatible = "ibm,p9-occ" or "ibm,p10-occ"
> -
> -Examples:
> -
> -    occ {
> -        compatible = "ibm,p9-occ";
> -    };
> diff --git a/Documentation/devicetree/bindings/fsi/ibm,p9-occ.yaml b/Documentation/devicetree/bindings/fsi/ibm,p9-occ.yaml
> new file mode 100644
> index 000000000000..3ab2582cb8a0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/fsi/ibm,p9-occ.yaml
> @@ -0,0 +1,41 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/fsi/ibm,p9-occ.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: IBM FSI-attached On-Chip Controller (OCC)
> +
> +maintainers:
> +  - Eddie James <eajames@xxxxxxxxxxxxx>
> +
> +description:
> +  The POWER processor On-Chip Controller (OCC) helps manage power and
> +  thermals for the system, accessed through the FSI-attached SBEFIFO
> +  from a service processor.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - ibm,p9-occ
> +      - ibm,p10-occ
> +
> +patternProperties:
> +  "^hwmon":

And now it raises questions:
1. Other devices on FSI bus have unit addresses, so why this does not?
2. This suggest only one hwmon, so ^hwmon$, which is then not a
patternProperty but property.
3. But the true problem why do you even need two empty nodes? These
should be combined into one node.

> +    type: object
> +    $ref: /schemas/hwmon/ibm,occ-hwmon.yaml
> +
> +required:
> +  - compatible
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    occ {
> +        compatible = "ibm,p9-occ";
> +
> +        hwmon {
> +            compatible = "ibm,p9-occ-hwmon";
> +        };
> +    };

Best regards,
Krzysztof