Hi Florian, On 14/02/18 13:09, Florian Echtler wrote: > Hello Hans, > > I've picked up work on the sur40 driver again recently. There is one major > feature left that is currently unsupported by the Linux driver, which is the > hardware-based calibration. > > The internal device memory contains a table with two bytes for each sensor pixel > (i.e. 960x540x2 = 1036800 bytes) that basically provide individual black and > white levels per-pixel that are used in preprocessing. The table can either be > set externally, or the sensor can be covered with a black/white surface and a > custom command triggers an internal calibration. > > AFAICT the usual V4L2 controls are unsuitable for this sort of data; do you have > any suggestions on how to approach this? Maybe something like a custom IOCTL? So the table has a fixed size? You can use array controls for that, a V4L2_CTRL_TYPE_U16 in a two-dimensional array would do it. See https://hverkuil.home.xs4all.nl/spec/uapi/v4l/vidioc-queryctrl.html for more information on how this works. Regards, Hans