Re: [PATCH v2 1/3] dt-bindings: chrome: Add Cros EC UCSI driver

[Rob Herring <robh@kernel.org>]

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.

What's PDC? What's UCSI?

> 
> Signed-off-by: Jameson Thies <jthies@google.com>
> ---
>  .../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

This is the exact same binding as google,cros-ec-typec.yaml. Why are you 
duplicating the whole thing rather than just adding a new compatible 
string?

Rob