Hi Riccardo,

On Thursday 19 March 2009 15:37:10 Riccardo Magliocchetti wrote:
> On Thu, Mar 19, 2009 at 2:38 PM, Laurent Pinchart
>
> <[email protected]> wrote:
> > On Wednesday 18 March 2009 20:35:28 Riccardo Magliocchetti wrote:
> >> Laurent Pinchart ha scritto:
> >> > On Monday 16 March 2009 21:43:41 Riccardo Magliocchetti wrote:
> >> >> hi,
> >> >>
> >> >> my syntek webcam (174f:5931) does not work with ekiga and cheese but
> >> >> it works fine with luvcview.
> >> >>
> >> >> The kernel is latest linus git tree v2.6.29-rc8-124-g5bee17f , libv4l
> >> >> is 0.5.9.
> >> >>
> >> >> I've attached lsusb -v output and this is cheese output:
> >> >> [snip]
> >> >> v4l2src name=video_source device=/dev/video0 ! capsfilter
> >> >> name=capsfilter
> >> >> caps=video/x-raw-rgb,width=800,height=600,framerate=7/1;video/x-raw-y
> >> >>uv, wid th=800,height=600,framerate=7/1 ! identity
> >> >> libv4l2: error setting pixformat: Device or resource busy
> >> >> libv4l2: error requesting 4 buffers: Device or resource busy
> >> >
> >> > The device seems to be already open. Use fuser to find out if an
> >> > application is using the video device.
> >>
> >> Unfortunately fuser reports the device opened only by cheese.
> >
> > The driver returns -EBUSY either when the device is already opened or if
> > the camera is streaming.
> >
> > Try to set the trace parameter to 255 (echo 255 >
> > /sys/modules/uvcvideo/parameters/trace). The driver will then print debug
> > messages to the kernel log, including a trace of the functions called by
> > the userspace application. You should then be able to check if the device
> > is opened twice, or if streaming has been started prior to the failed set
> > format call.
>
> Yes, i see the device opened twice but i cannot see more :)

That's definitely the problem. After calling VIDIOC_STREAMOFF to stop 
streaming, cheese doesn't close the device and opens another instance. This is 
likely a bug in cheese or libv4l2.

> One thing i've missed to report is that i have this on boot:
>
> Mar 19 14:59:13 montag kernel: [    5.639794] uvcvideo: UVC non
> compliance - GET_DEF(PROBE) not supported. Enabling workaround.

No need to worry about that. Your device isn't 100% UVC compliant, but the 
driver enables a workaround to fix the issue.

Best regards,

Laurent Pinchart

_______________________________________________
Linux-uvc-devel mailing list
[email protected]
https://lists.berlios.de/mailman/listinfo/linux-uvc-devel

Reply via email to