Hi Sergey On Thu, Mar 18, 2021 at 5:47 AM Sergey Senozhatsky <sergey.senozhatsky.work@xxxxxxxxx> wrote: > > On (21/03/17 08:58), Ricardo Ribalda Delgado wrote: > [..] > > > > > > GET_CUR? > > yep > > > > > > > > > https://www.kernel.org/doc/html/v4.13/media/uapi/v4l/vidioc-g-selection.html?highlight=vidioc_s_selection > > > > On success the struct v4l2_rect r field contains the adjusted > > > > rectangle. > > > > > > What is the adjusted rectangle here? Does this mean that firmware can > > > successfully apply SET_CUR and return 0, but in reality it was not happy > > > with the rectangle dimensions so it modified it behind the scenes? > > > > I can imagine that some hw might have spooky requirements for the roi > > rectangle (multiple of 4, not crossing the bayer filter, odd/even > > line...) so they might be able to go the closest valid config. > > Hmm. Honestly, I'm very unsure about it. ROI::SET_CUR can be a very > hot path, depending on what user-space considers to be of interest > and how frequently that object of interest changes its position/shape/etc. > Doing GET_CUR after every SET_CUR doubles the number of firmware calls > we issue, that's for sure; is it worth it - that's something that I'm > not sure of. > > May I please ask for more opinions on this? Could you try setting the roi in a loop in your device and verify that it accepts all the values with no modification. If so we can implement the set/get as a quirk for other devices. > > -ss -- Ricardo Ribalda
