On Mon, 25 Apr 2011, Thomas Lindroth wrote: > On 04/23/2011 10:17 PM, Alan Stern wrote: > > On Sat, 23 Apr 2011, Thomas Lindroth wrote: > >> On 04/23/2011 05:31 PM, Alan Stern wrote: > >>> Your separate post didn't include the dmesg showing what happened when > >>> you plugged the mouse into an EHCI controller. In fact, a usbmon trace > >>> of those events would be more useful than a dmesg log. Can you post > >>> one of those? It doesn't need to start until just before you plug in > >>> the mouse. > >> > >> I made some usbmon dumps of the mouse getting plugged in. I ran > >> usbmon > file, plugged the mouse in and ctrl + c after about 20 sec. > > > > This explains the problem with the EHCI controller. The mouse can't be > > used because the kernel thinks it would require more periodic bandwidth > > than is available on the bus. Now, I have no idea why 2.6.39 should > > behave differently from 2.6.38 in this respect. > Connecting the mouse to a EHCI port fails on both 2.6.28 and .29 but it > used to be possible to connect the mouse to a XHCI port prior to .29. (Presumably you mean .38 and .39 rather than .28 and .29.) Oh, sorry, I must have misunderstood your earlier message. Now it makes more sense. > > You have a bunch of devices all connected to the same EHCI controller. > > If you can attach the mouse to a different port, one that goes to the > > other EHCI controller, it might work better. > I looked into the periodic file and noticed that my Microsoft keyboard > 4000 used a whole lot of periodic bandwidth for some reason. I assumed > that a keyboard is a low bandwidth device and put it in the same > controller as the mouse. Moving the keyboard to the front usb panel > makes it possible to connect the mouse at the back panel :) Heh. A keyboard is low _speed_ ... but that very fact means it uses more bandwidth than you might think. Low speed signalling is 8 times slower than full speed, therefore it requires 8 times more bandwidth. > Thanks for you help. You're welcome. 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
