Re: [PATCH] docs: dt: writing-schema: Describe defining properties in top-level
From: Krzysztof Kozlowski
Date: Fri Sep 05 2025 - 02:49:15 EST
On 04/09/2025 17:30, Frank Li wrote:
>> diff --git a/Documentation/devicetree/bindings/writing-schema.rst b/Documentation/devicetree/bindings/writing-schema.rst
>> index 470d1521fa17..e0859094575d 100644
>> --- a/Documentation/devicetree/bindings/writing-schema.rst
>> +++ b/Documentation/devicetree/bindings/writing-schema.rst
>> @@ -165,6 +165,14 @@ The YAML Devicetree format also makes all string values an array and scalar
>> values a matrix (in order to define groupings) even when only a single value
>> is present. Single entries in schemas are fixed up to match this encoding.
>>
>> +When bindings cover multiple similar devices that differ in some properties,
>> +those properties should be constrained for each device. This usually means:
>> +
>> + * In top level 'properties' define the property with the broadest constraints.
>> + * In 'if:then:' blocks, further narrow the constraints for those properties.
>> + * Do not define the properties within an 'if:then:' block (note that
>> + 'additionalItems' also won't allow that).
>> +
>
> I can understand what your said. I think it would be better if add some
> simple examples.
Example for that is already there - at the bottom of this file.
Best regards,
Krzysztof