V4L2 issues in userpointer method implementation

[ShaneCCC]

Have a reference to this topic to check by v4l2-ctl-t186 and then reference to the MMAPI sample code.

V4l2 can't work with V4L_MEMORY_USERPTR in l4t-32.4.4

my custom camera work well with V4L2_MEMORY_MMAP option. it was checked like this: $ v4l2-ctl --set-fmt-video=width=1280,height=720,pixelformat=UYVY --stream-mmap --stream-count=1 -d /dev/video0 --verbose i want to set option V4L_MEMORY_USERPTR, i had try with --stream-user, but it was fail like this $ v4l2-ctl --set-fmt-video=width=1280,height=720,pixelformat=UYVY --stream-user --stream-count=1 -d /dev/video0 --verbose VIDIOC_QUERYCAP: ok VIDIOC_G_FMT: ok VIDIOC_S_FMT: ok Format Video Captu…