Re: [PATCH v2 1/3] dt-bindings: chrome: Add Cros EC UCSI driver
From: Rob Herring
Date: Wed Oct 08 2025 - 12:13:19 EST
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@xxxxxxxxxx>
> ---
> .../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@xxxxxxxxxxxx>
> + - Andrei Kuchynski <akuchynski@xxxxxxxxxxxx>
> + - Benson Leung <bleung@xxxxxxxxxxxx>
> + - Jameson Thies <jthies@xxxxxxxxxx>
> + - Łukasz Bartosik <ukaszb@xxxxxxxxxxxx>
> +
> +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