The UVC Gadget includes a hardcoded interrupt endpoint against the VideoControl interface, though it is misnamed as a control endpoint (the default endpoint 0 is actually used for that role). The UVC specification says that this is an optional feature of a UVC compliant camera provided certain scenarios don't hold true, specifically... 1. The device supports hardware triggers for still image capture 2. The device implements any AutoUpdate controls 3. The device implements any Asynchronous controls Those are all scenarios that will be determined by userspace, meaning that in some implementations the interrupt endpoint is unnecessary. There is an additional problem in that the current implementation of the uvc function driver contains no mechanism through which data can be sent over this endpoint, making it unuseable in any case. This series disables the endpoint by default but adds a configfs attribute allowing users to re-enable it if desired. Daniel Scally (3): usb: gadget: uvc: Rename uvc_control_ep usb: gadget: uvc: Add new enable_interrupt_ep attribute usb: gadget: uvc: Disable interrupt endpoint by default .../ABI/testing/configfs-usb-gadget-uvc | 4 +- drivers/usb/gadget/function/f_uvc.c | 76 +++++++++++-------- drivers/usb/gadget/function/u_uvc.h | 2 + drivers/usb/gadget/function/uvc.h | 3 +- drivers/usb/gadget/function/uvc_configfs.c | 53 +++++++++++++ 5 files changed, 104 insertions(+), 34 deletions(-) -- 2.34.1
