Hi, While I was writing a basic v4l2 video grabber I got a wierd bug which I've been discussing with pinchartl and devinheitmueller on freenode #v4l2. The problem is that my /dev/video0 devices disappears when I start my application and press CTRL-C without handling the signal/interupt and closing the devices correctly. When I run my application, and let it grab like 60 frames, then shutdown everything nicely the /dev/video0 is not removed. I can run my app multiple times w/o problems. This problem thus only occurs when I do not close/shutdown the camera correctly. I get this problem with both my own capturer, which I pasted here: https://gist.github.com/6b17e49bc33502f35c74 and also when I use this example app: http://linuxtv.org/downloads/legacy/video4linux/API/V4L2_API/v4l2spec/capture.c When I press CTRL-C when the app runs and my /dev/video0 is removed, I see this in /var/log/kern.log: -------------------------------------------------------- Jan 10 23:03:15 gtx kernel: [ 121.474062] usb 3-1: Not enough bandwidth for altsetting 0 Jan 10 23:03:20 gtx kernel: [ 126.477528] xhci_hcd 0000:00:14.0: xHCI host not responding to stop endpoint command. Jan 10 23:03:20 gtx kernel: [ 126.477533] xhci_hcd 0000:00:14.0: Assuming host is dying, halting host. Jan 10 23:03:20 gtx kernel: [ 126.477553] xhci_hcd 0000:00:14.0: HC died; cleaning up Jan 10 23:03:20 gtx kernel: [ 126.477595] usb 3-1: USB disconnect, device number 2 Jan 10 23:03:20 gtx kernel: [ 126.486697] xhci_hcd 0000:00:14.0: Slot 1 endpoint 14 not removed from BW list! Jan 10 23:03:20 gtx kernel: [ 126.486712] usb 3-2: USB disconnect, device number 3 Jan 10 23:03:20 gtx kernel: [ 126.486714] usb 3-2.2: USB disconnect, device number 4 Jan 10 23:03:20 gtx kernel: [ 126.533588] xhci_hcd 0000:00:14.0: Slot 3 endpoint 2 not removed from BW list! Jan 10 23:03:20 gtx kernel: [ 126.533593] xhci_hcd 0000:00:14.0: Slot 3 endpoint 4 not removed from BW list! Jan 10 23:03:20 gtx kernel: [ 126.533809] xhci_hcd 0000:00:14.0: Slot 2 endpoint 2 not removed from BW list! -------------------------------------------------------- Another thing to mention, is that my USB keyboard, which is on the same usb-bus also fails; I've to reboot (using ssh :-) ) to enable the devices again. Some more info which might tell more -------------------------------------------------------- $ v4l2-ctl --list-devices UVC Camera (046d:09a6) (usb-0000:00:14.0-1): /dev/video0 -------------------------------------------------------- $ lsusb Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 003 Device 002: ID 046d:09a6 Logitech, Inc. QuickCam Vision Pro Bus 003 Device 003: ID 05ac:1006 Apple, Inc. Hub in Aluminum Keyboard Bus 005 Device 002: ID 2109:0811 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 005 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 006 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 003 Device 004: ID 05ac:0221 Apple, Inc. Aluminum Keyboard (ISO) Bus 005 Device 003: ID 045e:076c Microsoft Corp. -------------------------------------------------------- Ubuntu 12.10 (GNU/Linux 3.5.0-21-generic x86_64) What can I do to look more into this and figure out why it's failing or how to find a workaround? Best roxlu -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
