Re: [PATCH] dt-bindings: usb: usb-device: Add panel-location

[Rob Herring <robh@kernel.org>]

On Thu, Dec 12, 2024 at 09:44:37PM +0000, Ricardo Ribalda wrote:
> For some devices like cameras the system needs to know where they are
> mounted.

Why do you need this and why only this property and not the dozens 
others ACPI has?

> 
> ACPI has a property for this purpose, which is parsed by
> acpi_get_physical_device_location():
> https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/06_Device_Configuration/Device_Configuration.html#pld-physical-location-of-device
> 
> In DT we have similar property for video-interface-devices called
> orientation, but it is limited to the requirements of video devices:
> Documentation/devicetree/bindings/media/video-interface-devices.yaml
> 
> Add a new property for usb-devices that matches the behavior of
> ACPI's _PLD.
> 
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
> ---
>  Documentation/devicetree/bindings/usb/usb-device.yaml | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/usb-device.yaml b/Documentation/devicetree/bindings/usb/usb-device.yaml
> index da890ee60ce6..1ce79c1c3b31 100644
> --- a/Documentation/devicetree/bindings/usb/usb-device.yaml
> +++ b/Documentation/devicetree/bindings/usb/usb-device.yaml
> @@ -42,6 +42,20 @@ properties:
>        port to which this device is attached. The range is 1-255.
>      maxItems: 1
>  
> +  panel-location:
> +    description: Describes which panel surface of the system's housing the USB
> +      device resides on. It has the same meaning as the `ACPI`'s `_PLD` Panel
> +      object.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum:
> +      - 0 # Top.
> +      - 1 # Bottom.
> +      - 2 # Left.
> +      - 3 # Right.
> +      - 4 # Front (aka as User Facing).
> +      - 5 # Back (aka as World Facing).
> +      - 6 # Unknown.
> +
>    "#address-cells":
>      description: should be 1 for hub nodes with device nodes,
>        should be 2 for device nodes with interface nodes.
> 
> ---
> base-commit: eefa7a9c069908412f8f5d15833901d1b46ae1b2
> change-id: 20241212-usb-orientation-8e3717ebb02a
> 
> Best regards,
> -- 
> Ricardo Ribalda <ribalda@chromium.org>
>