Re: [PATCH v2 1/1] schemas: i2c: Introduce I2C bus extensions

Luca Ceresoli <[email protected]> Fri, 2 May 2025 16:09:10 +0200
Newsgroups org.kernel.vger.devicetree-spec,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-i2c,org.kernel.vger.linux-kernel
Organization Bootlin
Message-ID <20250502160910.448f63dd@booty>
Hello Hervé,

On Wed, 30 Apr 2025 17:22:00 +0200
Herve Codina <[email protected]> wrote:

> An I2C bus can be wired to the connector and allows an add-on board to
> connect additional I2C devices to this bus.
> 
> Those additional I2C devices could be described as sub-nodes of the I2C
> bus controller node however for hotplug connectors described via device
> tree overlays there is additional level of indirection, which is needed
> to decouple the overlay and the base tree:
> 
>   --- base device tree ---
> 
>   i2c1: i2c@abcd0000 {
>       compatible = "xyz,i2c-ctrl";
>       i2c-bus-extension@0 {
>           i2c-bus = <&i2c_ctrl>;
>       };
>       ...
>   };
> 
>   i2c5: i2c@cafe0000 {
>       compatible = "xyz,i2c-ctrl";
>       i2c-bus-extension@0 {
>           i2c-bus = <&i2c-sensors>;
                        ^^^^^^^^^^^

This should be i2c_sensors (with an underscore)...

>       };
>       ...
>   };
> 
>   connector {
>       i2c_ctrl: i2c-ctrl {
>           i2c-parent = <&i2c1>;
>           #address-cells = <1>;
>           #size-cells = <0>;
>       };
> 
>       i2c-sensors {

...and this should have a label:

        i2c-sensors: i2c-sensors {

With those fixed you can add my:

+Reviewed-by: Luca Ceresoli <[email protected]>

-- 
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com