On Wed, Oct 01, 2025 at 07:33:41PM +0000, Jameson Thies wrote:
> Chrome OS devices with PDCs allow the host to read port status and
> control port behavior with UCSI commands sent to the embedded controller
> (EC). Add documentation for cros-ec-ucsi node which loads the Chrome OS
> UCSI driver.
> 
> Signed-off-by: Jameson Thies <jthies@google.com>

Reviewed-by: Benson Leung <bleung@chromium.org>


> ---
>  .../bindings/chrome/google,cros-ec-ucsi.yaml  | 71 +++++++++++++++++++
>  .../bindings/mfd/google,cros-ec.yaml          |  4 +-
>  2 files changed, 74 insertions(+), 1 deletion(-)
>  create mode 100644 Documentation/devicetree/bindings/chrome/google,cros-ec-ucsi.yaml
> 
> diff --git a/Documentation/devicetree/bindings/chrome/google,cros-ec-ucsi.yaml b/Documentation/devicetree/bindings/chrome/google,cros-ec-ucsi.yaml
> new file mode 100644
> index 000000000000..2121776e3ff0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/chrome/google,cros-ec-ucsi.yaml
> @@ -0,0 +1,71 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/chrome/google,cros-ec-ucsi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Google Chrome OS EC(Embedded Controller) UCSI driver.
> +
> +maintainers:
> +  - Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
> +  - Andrei Kuchynski <akuchynski@chromium.org>
> +  - Benson Leung <bleung@chromium.org>
> +  - Jameson Thies <jthies@google.com>
> +  - Łukasz Bartosik <ukaszb@chromium.org>
> +
> +description:
> +  Chrome OS devices with PDC-based USB-C ports expose a UCSI interface
> +  from the Embedded Controller (EC) which allows the host to request
> +  port state and control limited port behavior (DR/PR swap). This node
> +  allows the host UCSI driver to send and receive UCSI commands to a
> +  Chrome OS EC. The node for this device should be under a cros-ec node
> +  like google,cros-ec-spi.
> +
> +properties:
> +  compatible:
> +    const: google,cros-ec-ucsi
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +patternProperties:
> +  '^connector@[0-9a-f]+$':
> +    $ref: /schemas/connector/usb-connector.yaml#
> +    required:
> +      - reg
> +
> +required:
> +  - compatible
> +
> +additionalProperties: false
> +
> +examples:
> +  - |+
> +    spi {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      cros_ec: ec@0 {
> +        compatible = "google,cros-ec-spi";
> +        reg = <0>;
> +        interrupts = <35 0>;
> +
> +        typec {
> +          compatible = "google,cros-ec-ucsi";
> +
> +          #address-cells = <1>;
> +          #size-cells = <0>;
> +
> +          connector@0 {
> +            compatible = "usb-c-connector";
> +            reg = <0>;
> +            power-role = "dual";
> +            data-role = "dual";
> +            try-power-role = "source";
> +          };
> +        };
> +      };
> +    };
> diff --git a/Documentation/devicetree/bindings/mfd/google,cros-ec.yaml b/Documentation/devicetree/bindings/mfd/google,cros-ec.yaml
> index 50f457090066..646bc81c526f 100644
> --- a/Documentation/devicetree/bindings/mfd/google,cros-ec.yaml
> +++ b/Documentation/devicetree/bindings/mfd/google,cros-ec.yaml
> @@ -99,7 +99,9 @@ properties:
>    gpio-controller: true
>  
>    typec:
> -    $ref: /schemas/chrome/google,cros-ec-typec.yaml#
> +    oneOf:
> +      - $ref: /schemas/chrome/google,cros-ec-typec.yaml#
> +      - $ref: /schemas/chrome/google,cros-ec-ucsi.yaml#
>  
>    ec-pwm:
>      $ref: /schemas/pwm/google,cros-ec-pwm.yaml#
> -- 
> 2.51.0.618.g983fd99d29-goog
>