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. >> 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. >> FWIW: on these boards (same type, BIOS, etc) I also see the issue >> described at http://marc.info/?l=linux-kernel&m=137749729105329&w=2. >> Any correlation? > > Not that I can see. 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. Kind regards, Udo -- 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
