On Thu, 5 Jul 2012, Paul Menzel wrote: > Dear Linux folks, > > > an USB Logitech keyboard > > Bus 004 Device 003: ID 046d:c30f Logitech, Inc. Logicool HID-Compliant Keyboard (106 key) > > arbitrarily gets unresponsive on my system and stays this way. > > I am working in X and suddenly nothing entered to the keyboard has an > effect. I cannot switch to a virtual terminal with Ctrl + Alt + F<n>, n > ∈ ℕ, but the LEDs of the keyboard are still lighted. The USB mouse keeps > working though. > > After plugging it out and back in it works again. > > The distribution is Debian Sid/unstable with Linux 3.2 and it happened > with two mainboards, the ASUS M2A-VM [1] and ASRock A780FullHD [2]. Is the keyboard attached to an xHCI controller or something else (EHCI, UHCI, or OHCI)? > I also build the latest Linux from Git (ff826b2) with > `CONFIG_USB_DEBUG=y` set and it happened with it too. Unfortunately > nothing was logged to (n)either the Linux kernel ring buffer (`dmesg`) > (n)or `/var/log/Xorg.0.log`. > > Unfortunately I also do not have a way to reproduce this. If you have > some debugging hints for me, I would be able to log into the system over > SSH, when this happens again. > > One last observation, if I remember correctly the monitor went to > standby once after this had happened and I had not replugged it yet to > see if it comes back. If I did not accidentally moved the mouse, hitting > a key on the keyboard did bring the monitor out of standby. So some > signals still seem to be send. > > Any debugging tips are much appreciated! The next time this happens, try to acquire a usbmon trace (see the instructions in Documentation/usb/usbmon.txt). And for comparison, acquire another trace while the keyboard is working. Let's see if it sends the same data when you press the same keys in each situation. Alan Stern -- 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
