Hi Stephan, On Tuesday 10 November 2009 16:59:04 Stephan Diestelhorst wrote: > Hi Linux UVC developers, > apologies for spamming this list with an opened berlios bug item > (#103031), but the bugs there seem to not get any attention anymore.
No need to apologize. The berlios web-based support system is not actively used by the project. > This issue is with the built-in Bison web cam in an MSI Wind U100. Once the > camera is enabled (via hotkey), the entire USB subsystem is not responding > anymore, causing non-detection of freshly attached USB devices and prevents > suspending the box. > > The only fix so far is to blacklist the "uvcvideo" module or to keep the cam > disabled (with hotkey). > > This is with a stable 2.6.31-14-generic kernel on Ubuntu Karmic. > > A number of related resources: > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/435352 contains > many user reports. > > http://marc.info/?l=linux-kernel&m=125541673726384&w=2 a stalled > discussion on the LKML with more technical insight > > https://lists.berlios.de/pipermail/linux-uvc-devel/2009-September/005143.h > tml a stalled discussion on the linux-uvc-devel ML > > https://lists.berlios.de/pipermail/linux-uvc-devel/2009-September/005143.h > tml is (according to launchpad) the breaking changeset. > > This is a very unpleasant bug, as it affects the usability of the system a > lot and is a regression: Kernel 2.6.28 worked flawless with the webcam. Even though the git commit that caused the regression modifies the uvcvideo driver, this is an issue that need to be solved at the USB core level. The commit's purpose is to enable autosuspend, but a nasty side effect kills USB on some (buggy ?) controllers because an interrupt URB is canceled too fast after being submitted. > Keep up the good work! Thanks. > Many thanks and again, sorry for cross-posting, Once again no apologize needed. You should keep cross-posting and report the problem to the linux-usb mailing list. I'm not familiar enough with the EHCI architecture to work on a fix, so the solution will likely come from linux-usb developers. -- Regards, Laurent Pinchart _______________________________________________ Linux-uvc-devel mailing list Linux-uvc-devel@lists.berlios.de https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
