Re: [PATCH v2 1/1] schemas: i2c: Introduce I2C bus extensions
From: Luca Ceresoli
Date: Fri May 02 2025 - 10:09:27 EST
Hello Hervé,
On Wed, 30 Apr 2025 17:22:00 +0200
Herve Codina <herve.codina@xxxxxxxxxxx> 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 <luca.ceresoli@xxxxxxxxxxx>
--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com