Re: [PATCH v4 1/2] dt-bindings: drm/bridge: ti-tmds181: Add TI TMDS181 and SN65DP159 bindings

[Krzysztof Kozlowski <krzk@kernel.org>]

On 02/09/2025 16:52, Mike Looijmans wrote:
>> if:
>>   properties:
>>     compatible:
>>       contains:
>>         const: ti,sn65dp159
>> then:
>>   properties:
>>     ti,sink-mode:
>>       type: boolean
>>       description:
>>         Force chip to operate in "sink" mode. Allows to use
>>         a DP159 chip (defaults to source) for incoming signals.
>>     ti,dvi-mode:
>>       type: boolean
>>       description: Makes the DP159 chip operate in DVI mode.
>>     slew-rate:
>>       $ref: /schemas/types.yaml#/definitions/uint32
>>       minimum: 0
>>       maximum: 3
>>       default: 3
>>       description: Set slew rate, 0 is slowest, 3 is fastest.
>> else:
>>   properties:
>>     ti,source-mode:
>>       type: boolean
>>       description:
>>         Force chip to operate in "source" mode. Allows to use
>>         a TMDS181 chip (which defaults to sink) as cable driver.
>>
> Hmm, apparently one cannot "add" properties in the "if:" block? The 

One can, but should not. Define properties in top level and disallow them.

See also example-schema.


> opposite approach, disallowing properties, works, e.g.:
> 
> if:
>    properties:
>      compatible:
>        contains:
>          const: ti,sn65dp159
> then:
>    properties:
>      ti,source-mode: false
> else:
>    properties:
>      ti,sink-mode: false
>      ti,dvi-mode: false
>      slew-rate: false


So any device can work in any mode? Then this should be just enum with
different defaults.

Best regards,
Krzysztof