Re: [PATCH 07/10] dt-bindings: rng: add st,rng-lock-conf

[Gatien CHEVALLIER <gatien.chevallier@foss.st.com>]

On 9/15/23 12:33, Krzysztof Kozlowski wrote:
> On 15/09/2023 11:28, Gatien CHEVALLIER wrote:
>> Hello Rob,
>>
>> On 9/11/23 17:09, Rob Herring wrote:
>>> On Fri, Sep 08, 2023 at 06:51:17PM +0200, Gatien Chevallier wrote:
>>>> If st,rng-lock-conf is set, the RNG configuration in RNG_CR, RNG_HTCR
>>>> and RNG_NSCR will be locked. It is supported starting from the RNG
>>>> version present in the STM32MP13
>>>
>>> This should be squashed into the prior binding patch.
>>>
>>>>
>>>> Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
>>>> ---
>>>>    .../devicetree/bindings/rng/st,stm32-rng.yaml      | 14 ++++++++++++++
>>>>    1 file changed, 14 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/rng/st,stm32-rng.yaml b/Documentation/devicetree/bindings/rng/st,stm32-rng.yaml
>>>> index 59abdc85a9fb..0055f14a8e3f 100644
>>>> --- a/Documentation/devicetree/bindings/rng/st,stm32-rng.yaml
>>>> +++ b/Documentation/devicetree/bindings/rng/st,stm32-rng.yaml
>>>> @@ -37,6 +37,20 @@ required:
>>>>      - reg
>>>>      - clocks
>>>>    
>>>> +allOf:
>>>> +  - if:
>>>> +      properties:
>>>> +        compatible:
>>>> +          contains:
>>>> +            enum:
>>>> +              - st,stm32mp13-rng
>>>> +    then:
>>>> +      properties:
>>>> +        st,rng-lock-conf:
>>>> +          type: boolean
>>>> +          description: If set, the RNG configuration in RNG_CR, RNG_HTCR and
>>>> +                       RNG_NSCR will be locked.
>>>
>>> Define the property at the top-level and then restrict its presence in
>>> a if/then schema.
>>>
>>
>> Can you please point me to an example of such case. I can't find a way
>> to define at the top-level the property then restrict it to specific
>> compatibles.
> 
> You can check my slides from the talks about not reaching 10 iterations
> of bindings patches.
> 
> Or open example-schema (this should be your starting point):
> https://elixir.bootlin.com/linux/v5.19/source/Documentation/devicetree/bindings/example-schema.yaml#L212
> 
> 
> Also:
> https://elixir.bootlin.com/linux/v6.4-rc7/source/Documentation/devicetree/bindings/net/qcom,ipa.yaml#L174

Thank you for the links, it really helped me out.

>>
>> Else I'd change
>> additionalProperties :false to
>> unevaluatedProperties: false
>>
>> so the definition of the property is seen.
> 
> No, why? Definition is there when you move it to the top as asked.
> 
> Best regards,
> Krzysztof
>