Laurent Pinchart [off-list ref] writes:

quoted

+  reg:
+    description: I2C bus address of the sensor device

You can drop this, it's implicit for I2C devices.

Do you mean just dropping these two lines (and MaxItems: 1), and leaving
"reg" in "required" and in the example? E.g.:
...
required:
  - compatible
  - reg
  - clocks
  - clock-names
  - port

additionalProperties: false

examples:
  - |
    #include <dt-bindings/gpio/gpio.h>
    #include <dt-bindings/clock/imx6qdl-clock.h>

    i2c {
            #address-cells = <1>;
            #size-cells = <0>;

            ar0521: camera-sensor@36 {
                    compatible = "onnn,ar0521";
                    reg = <0x36>;
                    pinctrl-names = "default";

...

It protests with:

Documentation/devicetree/bindings/media/i2c/onnn,ar0521.example.dt.yaml:
camera-sensor@36: 'reg' does not match any of the regexes: 'pinctrl-[0-9]+'
        From schema: /usr/src/linux/imx6/Documentation/devicetree/bindings/media/i2c/onnn,ar0521.yaml

Thus I'm currently leaving it as is.
-- 
Krzysztof Hałasa

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