On Wed, 28 Aug 2013, Udo van den Heuvel wrote: > On 2013-08-27 19:43, Alan Stern wrote: > >>> rmmod ohci-pci > >>> modprobe dummy-irq irq=18 > >>> > >>> and see if the IRQ line gets disabled after that. > >> > >> Can I actually use that irq/ports that way? (as with no usage the > >> problem does not occur) > > > > No, if you unload the ohci-hcd driver then the webcam won't be used. > > Are you certain that merely stopping the daemon program will prevent > > the problem? > > Quite certain but retesting can confirm that. Maybe without activity, the OHCI controller goes into suspend. You can prevent it by doing: echo on >/sys/bus/pci/devices/0000:00:13.1/usb?/power/control If you do this and stop using the webcam, but leave ohci-hcd bound to the controller, does the problem occur? > >> No ohci_pci, is that a problem? > > > > Sorry, for 3.10 it should be ohci_hcd. In 3.11 it changed to ohci_pci. > > 3.10.9 is the latest here. > > > Have you tried getting a USB-2 hub and plugging the webcam into it? > > That will make a good test: You'll be able to use the webcam without > > it affecting the ohci-hcd driver. > > Not yet but I'll have hubs to test with soon. > > > As a second test, you can try plugging everything _except_ the webcam > > into the hub. > > To see if the webcam itself is a factor. I see. By the way, since you switched to the new computer, are there any devices attached to this USB bus other than the webcam? Also, at one point you had a second webcam attached to a different OHCI controller, as well as a Bluetooth device and a USB-serial device. Are they still present? > This afternoon I found a 3.8.10 kernel with the disabled irq 18 and some > ^@^@^@ characters on teh console. > After I did: > > service motion stop > rmmod pwc > echo 0000:00:13.0 >/sys/bus/pci/drivers/ohci_hcd/unbind > echo 0000:00:13.0 >/sys/bus/pci/drivers/ohci_hcd/bind > modprobe pwc > service motion start > > the ^@^@^@ appeared to stop. > I'll try to watch /proc/interrupts to see if the ^@^@ correlate with > i8042 interrupts. Maybe they are related somehow, but I have no idea how. 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
