uvcvideo: Dropping payload (out of sync)

Hi,

I ran into a problem while trying to get a "Microsoft LifeCam Studio(TM)" (045e:0772) to work with uvccapture on a Raspberry PI running Kernel 3.6.11 under Debian Wheezy.

I started grabbing a picture with:
/usr/bin/uvccapture -x1920 -y1080 -o/media/ramdisk/webcam.jpg -q80

[1] http://ftp.de.debian.org/debian/pool/main/u/uvccapture/uvccapture_0.5.orig.tar.gz
[2] http://ftp.de.debian.org/debian/pool/main/u/uvccapture/uvccapture_0.5-2.debian.tar.gz

Grabbing a picture takes between 20 seconds and 1-2 minutes. Unfortuantely the captured image is heavily distorted.

Doing a stack trace I see that it always hangs on:

ioctl(3, VIDIOC_STREAMON, 0xbe8f15e4) = 0
ioctl(3, VIDIOC_DQBUF

So I did an:
echo 0xffff > /sys/module/uvcvideo/parameters/trace

This resulted in a rather lengthy kernel log starting like this:

Apr 10 07:08:11 raspberrypi kernel: [ 5262.503209] uvcvideo: uvc_v4l2_ioctl(VIDIOC_G_CTRL)
Apr 10 07:08:11 raspberrypi kernel: [ 5262.509395] uvcvideo: uvc_v4l2_ioctl(VIDIOC_QUERYCTRL)
Apr 10 07:08:11 raspberrypi kernel: [ 5262.509466] uvcvideo: Control 0x00980913 not found.
Apr 10 07:08:11 raspberrypi kernel: [ 5262.519683] uvcvideo: uvc_v4l2_ioctl(VIDIOC_STREAMON)
Apr 10 07:08:11 raspberrypi kernel: [ 5262.524446] uvcvideo: Device requested 3072 B/frame bandwidth.
Apr 10 07:08:11 raspberrypi kernel: [ 5262.524481] uvcvideo: Selecting alternate setting 24 (3072 B/frame bandwidth).
Apr 10 07:08:11 raspberrypi kernel: [ 5262.534925] uvcvideo: Allocated 5 URB buffers of 32x3072 bytes each.
Apr 10 07:08:11 raspberrypi kernel: [ 5262.540632] uvcvideo: uvc_v4l2_ioctl(VIDIOC_DQBUF)
Apr 10 07:08:12 raspberrypi kernel: [ 5263.014155] uvcvideo: USB isochronous frame lost (-63).
Apr 10 07:08:12 raspberrypi kernel: [ 5263.019468] uvcvideo: USB isochronous frame lost (-63).
Apr 10 07:08:12 raspberrypi kernel: [ 5263.024473] uvcvideo: USB isochronous frame lost (-63).
Apr 10 07:08:12 raspberrypi kernel: [ 5263.068612] uvcvideo: USB isochronous frame lost (-63).
Apr 10 07:08:12 raspberrypi kernel: [ 5263.078582] uvcvideo: USB isochronous frame lost (-63).
Apr 10 07:08:12 raspberrypi kernel: [ 5263.327576] uvcvideo: USB isochronous frame lost (-63).
Apr 10 07:08:12 raspberrypi kernel: [ 5263.366721] uvcvideo: Frame complete (overflow).
Apr 10 07:08:12 raspberrypi kernel: [ 5263.366759] uvcvideo: Dropping payload (out of sync).

It continued to show over 1Mio lines in 5 minutes with:

Apr 10 07:08:12 raspberrypi kernel: [ 5263.371102] uvcvideo: Dropping payload (out of sync).

intermitted by a few:

Apr 10 07:08:12 raspberrypi kernel: [ 5263.388864] uvcvideo: USB isochronous frame lost (-63).

After enabling the trace uvccapture was not able to garb an image at all. I had to kill the process.

I am at loss here... The whole setup worked flawlessly on my Laptop with Debian Wheezy and kernel 3.2 on an Intel Chipset.

I did a few more tests lowering the capture resolution which seemed to work a lot better. Up to 800x600 the images were captured almost instantly, but they were still distorted. At the resolution of 640x480 the images were finally clear. But since the camera supports 1920x1080, I would also like to be able to capture at this resolution...

Any help is greatly appreciated.

Thanks in advance.
André

For anyone who may also run into this problem here is a solution...

It seems the problem is hardware related to the Raspberry Pi. The solution can be found here:

https://github.com/raspberrypi/linux/issues/238
https://github.com/P33M/linux

André

Yup, it's been known for a while that the USB host controller on the Raspberry Pi is absolute crap. For all the great things about the Pi, I would probably consider this it's biggest weakness (it's actually prompted me to *not* use the Pi for several projects where I needed a low-cost Linux platform)...

No easy answers here. It just won't be a very good platform for capturing uncompressed video over its USB port.

Devin

Devin J. Heitmueller - Kernel Labs
http://www.kernellabs.com