Hi Hans (de Goede, but others are welcome as well :) ) Some notebooks have a button to disable the camera (not to be mistaken with the mechanical cover). This is a standard GPIO linked to the camera via the ACPI table. 4 years ago we added support for this button in UVC via the Privacy control. This has two issues: - If the camera has its own privacy control, it will be masked - We need to power-up the camera to read the privacy control gpio. We tried to fix the power-up issues implementing "granular power saving" but it has been more complicated than anticipated.... Last year, we proposed a patchset to implement the privacy gpio as a subdevice https://lore.kernel.org/linux-media/20230111-uvc_privacy_subdev-v1-0-f859ac9a01e3@xxxxxxxxxxxx/ I think it is a pretty clean solution and makes sense to use a subdevice for something that is a sub device of the camera :). Before moving forward, Laurent and I would like to hear your opinion. Regards! -- Ricardo Ribalda
