Re: [PATCH 1/2] dt-bindings: i3c: dw: Add property to select IBI ops

Krzysztof Kozlowski
2024-06-26T08:06:28Z

On 26/06/2024 07:31, Jeremy Kerr wrote:
> Hi Aniket,
>
>> Use this property to select IBI related ops in the base platform
>> driver. Otherwise the driver defaults to return EINVAL for any IBI
>> requests.
>
> [...]
>
>> --- a/Documentation/devicetree/bindings/i3c/snps,dw-i3c-master.yaml
>> +++ b/Documentation/devicetree/bindings/i3c/snps,dw-i3c-master.yaml
>> @@ -25,6 +25,10 @@ properties:
>>    interrupts:
>>      maxItems: 1
>>
>> +  ibi-capable:
>> +    description: Set to select IBI ops.

What are IBI ops? Standard form letter:

You described the desired Linux feature or behavior, not the actual
hardware. The bindings are about the latter, so instead you need to
rephrase the property and its description to match actual hardware
capabilities/features/configuration etc.

>> +    type: boolean
>> +
>
> Wouldn't the compatible string select whether the hardware instance
> supports IBI or not?
>
> I'd imagine that each specific synthesis of the DW IP would imply
> corresponding hardware settings, and so would warrant its own compatible
> value.
>
> Maybe one for the DT folks: would this work better as individual
> properties? Is there a policy here?

Usually if feature is specific to given hardware, e.g. always capable of
foobar, then it can be deduced from compatible, so no need for new property.

Best regards,
Krzysztof