From: Hans Verkuil <hans.verkuil@xxxxxxxxx> I tried to get this in back in 2015, but that effort stalled. Trying again, since I really need this in order to add proper v4l-subdev support to v4l2-ctl and v4l2-compliance. There currently is no way of unique identifying that the device really is a v4l-subdev device other than the device name (which can be changed by udev). So this patch series adds a VIDIOC_SUBDEV_QUERYCAP ioctl that is in the core so it's guaranteed to be there. If the subdev is part of an MC then it also gives the corresponding entity ID of the subdev and the major/minor numbers of the MC device so v4l2-compliance can relate the subdev device directly to the right MC device. The reserved array has room enough for strings should we need them later. Hans Verkuil (2): v4l2-subdev: add VIDIOC_SUBDEV_QUERYCAP ioctl v4l: document VIDIOC_SUBDEV_QUERYCAP Documentation/media/uapi/v4l/user-func.rst | 1 + .../media/uapi/v4l/vidioc-subdev-querycap.rst | 118 +++++++++++++++++++++ drivers/media/v4l2-core/v4l2-subdev.c | 26 +++++ include/uapi/linux/v4l2-subdev.h | 29 +++++ 4 files changed, 174 insertions(+) create mode 100644 Documentation/media/uapi/v4l/vidioc-subdev-querycap.rst -- 2.13.1
