Hi Rob On Tue, 17 Dec 2024 at 16:02, Rob Herring <robh@xxxxxxxxxx> wrote: > > 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? Userspace needs that information to correctly show it in the UI. Eg; - User facing camera needs to be mirrored during preview. - The user facing camera is selected by default during videoconferences - The world facing camera is selected by default when taking a photo - User facing camera have different parameter defaults than world facing. Right now, the only camera driver that expose the ACPI location information is the IPU from intel https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/media/pci/intel/ipu-bridge.c#n258 And they are only using the panel. If we need more information we can consider adding more parameters in the future. > > > > > 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@xxxxxxxxxxxx> > > --- > > 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@xxxxxxxxxxxx> > > -- Ricardo Ribalda
