Hi, On Wednesday 23 September 2009 15:51:51 Iodine wrote: > Hello, Laurent! > > > > I have a usb webcam A4 TECH USB2.0 PC Camera J (0ac8:c40a). > > > > Please send me the output of > > lsusb -v -d 0ac8:c40a > > See it in attach.
Thanks. > > There's nothing wrong as such. This means that the driver doesn't receive > > complete images from the camera. > > But why "native" Ubuntu 9.04 uvcvideo driver does receive it and "new" > driver doesn't? Good question :-) > > Are you capturing MJPEG or YUYV data ? > > This camera support only MJPEG: > [1] cap.driver: "uvcvideo" > [1] cap.card: "A4 TECH USB2.0 PC Camera J" > [1] cap.bus_info: "usb-0000:00:1f.2-2" > [1] cap.capabilities=0x04000001 > [1] - VIDEO_CAPTURE > [1] - STREAMING > [1] Supported palettes: > [1] 0: MJPG (MJPEG) > > > Does the driver print anything to the kernel log ? > > There is nothing interesting :( [snip] > Laurent, what OS are you using for developing this driver? I can try to > install it and test this webcam. I'm using Gentoo, but I don't think your problem is distribution-related. I've checked the Ubuntu 2.6.28-11-generic kernel and it adds two patches to the 2.6.28 uvcvideo driver. One of them sets a quirk for an unrelated webcam, and the other one is https://lists.ubuntu.com/archives/kernel-team/2008- November/003563.html. Your problem is then probably caused by a regression in the uvcvideo driver between 2.6.28 and now. Could you try bisect the problem ? If you're not familiar with the concept it will be easier to start by trying vanilla kernels 2.6.28, 2.6.29, 2.6.30 and 2.6.31, and tell me at which version your webcam starts failing (2.6.28 should work). -- Regards, Laurent Pinchart _______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
