Hi Edgar, I'm adding UVC maintainer to CC, he might have missed this email. Could you also tell us what cameras have those features? A recent patch from me extends the UVC driver use of the Interrupt endpoint for asynchronous control completion notifications. This would be another extension for the same interface. I guess the way to implement it would be using V4L events. Thanks Guennadi On Mon, 7 Aug 2017, Edgar Thier wrote: > Hi all, > > I have some USB-3.0 cameras that use UVC. > These cameras offer auto updates for various properties. > An example of such a property would be gain, that will be adjusted when activating the auto-gain > property. These property changes are not queried by the UVC driver, unless it already has the > property marked as auto update via UVC_CTRL_FLAG_AUTO_UPDATE. > >From what I have seen, it seems that this flag is not checked when indexing the camera controls. > However it is checked when using extension units, so all properties loaded through such a unit are > being updates as one would hope. > > My questions: > > Is it intended that properties cannot mark themselves as autoupdate? > If yes: > Is there a recommended way of working around this? > Do all autoupdate properties have to be in an extension unit? > If no: > What should a fix look like? > > Regards, > > Edgar >