Re: [PATCH 2/3] dt-bindings: media: i2c: Add vision-components,mipi-module-controller

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] dt-bindings: schema rejects i2c child nodes due to unevaluatedProperties
- [Low] dt-bindings: dtc warning unit_address_vs_reg due to missing reg in i2c node
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commit 0c92fd00fde60c6a3a9d90ca2a635a3a6b317fc1
Author: Richard Leitner <richard.leitner@linux.dev>

dt-bindings: media: i2c: Add vision-components,mipi-module-controller

This commit adds device tree bindings for the Vision Components MIPI Camera
Module Controller. The controller abstracts the camera sensor behind a unified
register interface and exposes a tunneled downstream I2C bus for the attached
image sensor.

> diff --git a/Documentation/devicetree/bindings/media/i2c/vision-components,mipi-module-controller.yaml b/Documentation/devicetree/bindings/media/i2c/vision-components,mipi-module-controller.yaml
> new file mode 100644
> index 0000000000000..2a031aea68457
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/i2c/vision-components,mipi-module-controller.yaml

[ ... ]

> +required:
> +  - compatible
> +  - reg
> +  - '#clock-cells'
> +  - clock-frequency
> +  - vcc-supply
> +  - '#address-cells'
> +  - '#size-cells'
> +
> +unevaluatedProperties: false

[Severity: Medium]
Will this constraint reject the downstream I2C bus child node?

Because unevaluatedProperties is set to false but there is no definition
(such as a patternProperties for ^i2c@[0-9a-f]+$) for the tunneled downstream
I2C bus child node in the properties section, make dt_binding_check will fail
validation for any device tree containing this hardware module's child node.

> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        vc_mipi_ctrl: controller@10 {
> +            compatible = "vision-components,mipi-module-controller";
> +            reg = <0x10>;
> +            #clock-cells = <0>;
> +            clock-frequency = <37125000>;
> +            vcc-supply = <&cam_3v3>;
> +
> +            #address-cells = <1>;
> +            #size-cells = <0>;
> +
> +            i2c@0 {
> +                #address-cells = <1>;
> +                #size-cells = <0>;

[Severity: Low]
Does this child node trigger a dtc unit_address_vs_reg warning?

The parent node controller@10 defines #address-cells = <1>, and this i2c@0
node has a unit address. Without a corresponding reg = <0>; property, it
violates Device Tree syntax and will trigger a warning during
make dt_binding_check.

Additionally, this example illustrates the usage of the i2c@0 child node,
which is paradoxically forbidden by the unevaluatedProperties schema
constraint mentioned above.

> +
> +                vc_mipi_sensor: camera@60 {
> +                    compatible = "ovti,ov9281";
> +                    reg = <0x60>;

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260915-vc-mipi-ctrl-v1-0-8a42b693d889@linux.dev?part=2