Comment 27 for bug 196811

If you want a version of the qc-usb module, which builds on hardy, use the version from the ubuntu/media/quickcam directory of http://archive.ubuntu.com/ubuntu/pool/main/l/linux-ubuntu-modules-2.6.24/linux-ubuntu-modules-2.6.24_2.6.24-19.28.tar.gz
Then copy the Makefile from the normal archive downloaded from the website over to this directory, apply the patch and run "make quickcam.ko", thats how I created the module. (Well I also added some defines, because otherwise it wouldn't build on a 2.6.26 kernel)

And from the cheese faq:
"My Quickcam Express (qc-usb driver) doesn't work with Cheese (or gstreamer), and I see errors like "Not enough buffers. We got 1, we want at least 2" in the Cheese output.

Try running qcset /dev/video0 compat=dblbuf to enable double buffer compatibility mode, then restarting Cheese. "
(qcset is part of qc-usb-utils)

After doing this I got the cam working with cheese, now the question remains, why it worked without this before.
I also had this double-buffering issue when running a gstreamer-testpipeline:
gst-launch-0.10 v4lsrc autoprobe-fps=false device=/dev/video0 !\
"video/x-raw-yuv, format=(fourcc)YUY2, width=360, height=296, framerate=(fraction)15/2" ! ffmpegcolorspace !\
ximagesink
So it happens without hal being involved, too.
However this pipeline used to work for me before, thats why I thought it might have been some changes in gstreamer in intrepid.