Hi Michael,

On Friday 03 May 2013 00:34:40 Michael Grzeschik wrote:
> On Fri, May 03, 2013 at 12:18:21AM +0200, Laurent Pinchart wrote:
> > On Friday 03 May 2013 01:13:48 Vladimir Zapolskiy wrote:
> > > This change removes redundant calls to uvc_function_connect() and
> > > uvc_function_disconnect() on V4L2 device node open and release.
> > > 
> > > These two functions attemp to control pull-up on D+ line directly,
> > > however such an action should be performed by an UDC iteself, and within
> > > the gadget there is no information about current mode of the controller.
> > > 
> > > The UDC may be in suspended state, or an OTG controller may be in host
> > > mode, therefore it seems better not to try to forcibly pull-up D+ line
> > > on open() syscall.
> > 
> > OK, but we then need to fix the problem properly. The UVC gadget must not
> > appear connected until an application opens the corresponding device.
> > Likewise, it must disconnect from the bus when the application closes the
> > device. How can this be guaranteed properly ?
> 
> I think a lot of the userspace Testapplication [ยน] itself needs to
> be moved into the kernel. I.e. a lot of the function uvc_events_process
> needs to be handled in kernelspace. This way, the gadget would not even
> depent on an userspace application to be ready for.

I'm open to suggestions :-) What features of the userspace application do you 
think could (and should) be moved to kernelspace ? Many of them are highly 
application-specific.

-- 
Regards,

Laurent Pinchart

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