[PATCH v3 1/3] dt-bindings: media: Add bindings for THine THP7312 ISP

[Krzysztof Kozlowski]

On 15/10/2023 14:39, Laurent Pinchart wrote:
>>> +        properties:
>>> +          data-lanes:
>>> +            description:
>>> +              This property is for lane reordering between the THP7312 and the
>>> +              SoC. The sensor supports either two-lane, or four-lane operation.
>>> +              If this property is omitted four-lane operation is assumed. For
>>> +              two-lane operation the property must be set to <1 2>.
>>> +            minItems: 2
>>> +            maxItems: 4
>>> +            items:
>>> +              maximum: 4
>>> +
>>> +  sensors:
>>> +    type: object
>>> +    description: List of connected sensors
>>
>> I don't understand why do you list sensors here. From the binding
>> description I understood these are external sensors, which usually sit
>> on I2C bus.
> 
> Good question :-)
> 
> The sensors connected to the THP7312 input are controlled over I2C by
> the THP7312 itself. The host operating system doesn't have access to
> that I2C bus. The sensors are listed here because their power supplies
> need to be controlled by the host operating system.

OK

> 
>>> +
>>> +    properties:
>>> +      "#address-cells":
>>> +        const: 1
>>> +
>>> +      "#size-cells":
>>> +        const: 0
>>> +
>>> +    patternProperties:
>>> +      "^sensor@[01]":
>>> +        type: object
>>> +        description:
>>> +          Sensors connected to the first and second input, with one node per
>>> +          sensor.
>>> +
>>> +        properties:
>>> +          thine,model:
>>> +            $ref: /schemas/types.yaml#/definitions/string
>>> +            description:
>>> +              Model of the connected sensors. Must be a valid compatible string.
>>
>> Then why this isn't compatible?
> 
> We picked a vendor-specific property to avoid implying that the sensor
> nodes will result in devices being created by the host operating system.
> I don't mind using "compatible" instead, but as far as I understand, a
> compatible string implies that corresponding device DT bindings should
> exist, and that won't be the case here necessarily.

OK, looks sensible to me.

Best regards,
Krzysztof