'morning, could some one help clarifying me this note in the user control documentation ?
https://linuxtv.org/downloads/v4l-dvb-apis/uapi/v4l/control.html#f1
specifically: " In order to resolve this drivers use unique IDs and the V4L2_CID_PRIVATE_BASE IDs are mapped to those unique IDs by the kernel." - what are 'unique IDs' and how is the mapping performed?
Drivers with private controls assign them control IDs that are unique (see v4l2-controls.h, search for V4L2_CID_USER_MEYE_BASE).
hverkuil: oh, so each driver in mainline has a "space" reserved above V4L2_CID_USER_BASE
In order to still make them available for applications that do not use V4L2_CTRL_FLAG_NEXT_CTRL all private controls are also made available under IDs starting from V4L2_CID_PRIVATE_BASE.
The control framework counts the number of private controls (say N) and then assigns them as well to the range PRIVATE_BASE ... PRIVATE_BASE + N - 1
so that the application does not need to know the offset from USER_BASE of the driver specific control, and will always use PRIVATE_BASE instead
hverkuil: nice! thanks for your answer ;)
apps shouldn't use PRIVATE_BASE, instead enumerate over controls using V4L2_CTRL_FLAG_NEXT_CTRL.
sailus: Documentation/media/uapi/v4l/vidioc-g-fmt.rst was never extended with the struct v4l2_meta_format meta field. Can you make a patch for that?
I just noticed that it was missing from the struct v4l2_format documentation.
awa7
hverkuil: Good point.
I'll cc you.
hverkuil: Sent.
hverkuil: ping
mchehab: pong
hverkuil: you forgot to re-send the vivid patch with the corrected intervals :-)
Not my patch.
Haven't received the corrected patch yet.
ah, true
I did make a pull request for the v4l2-tpg hflip bug.
yes, and I applied
Ah, yes. Nice.