Re: [PATCH v1 09/30] reset: starfive: jh7100: Move necessary properties to device tree

[Rob Herring <robh@xxxxxxxxxx>]

On Thu, Sep 29, 2022 at 10:32:04PM +0800, Hal Feng wrote:
> Store the necessary properties in device tree instead of .c file,
> in order to apply this reset driver to other StarFive SoCs.
> 
> Signed-off-by: Hal Feng <hal.feng@xxxxxxxxxxxxxxxxxxxxxx>
> ---
>  .../bindings/reset/starfive,jh7100-reset.yaml | 20 ++++++++
>  arch/riscv/boot/dts/starfive/jh7100.dtsi      |  3 ++
>  drivers/reset/reset-starfive-jh7100.c         | 50 +++++++++++++------
>  3 files changed, 57 insertions(+), 16 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/reset/starfive,jh7100-reset.yaml b/Documentation/devicetree/bindings/reset/starfive,jh7100-reset.yaml
> index 300359a5e14b..3eff3f72a1ed 100644
> --- a/Documentation/devicetree/bindings/reset/starfive,jh7100-reset.yaml
> +++ b/Documentation/devicetree/bindings/reset/starfive,jh7100-reset.yaml
> @@ -20,19 +20,39 @@ properties:
>    "#reset-cells":
>      const: 1
>  
> +  starfive,assert-offset:
> +    description: Offset of the first ASSERT register
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +
> +  starfive,status-offset:
> +    description: Offset of the first STATUS register
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +
> +  starfive,nr-resets:
> +    description: Number of reset signals
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +
>  required:
>    - compatible
>    - reg
>    - "#reset-cells"
> +  - starfive,assert-offset
> +  - starfive,status-offset
> +  - starfive,nr-resets

Adding required properties is a red flag. You can't add required 
properties to an existing binding. That breaks the ABI unless the OS 
deals with the properties being absent. If the OS has to do that, then 
why add them in the first place? All this should be implied by the 
compatible string.

Rob