On Sun, Apr 26, 2009 at 4:09 PM, Phil Endecott <spam_from_x...@chezphil.org> wrote: > Dear Experts, > > I have a Griffin Powermate; it's a USB "knob" that you can use for > scrolling etc. This morning the computer that it was attached to > died. I'm now having trouble getting to work with the substitute machine. > > It looks like I have the kernel stuff working OK: > > # od -x > /dev/input/by-id/usb-Griffin_Technology__Inc._Griffin_PowerMate-event-misc > 0000000 e5f3 49f4 6a00 000c 0002 0007 ffff ffff > 0000020 e5f3 49f4 6a1d 000c 0000 0000 0000 0000 > 0000040 e5f3 49f4 dae9 000e 0002 0007 ffff ffff > 0000060 e5f3 49f4 dafa 000e 0000 0000 0000 0000 > 0000100 e5f3 49f4 3897 000f 0002 0007 ffff ffff > 0000120 e5f3 49f4 38aa 000f 0000 0000 0000 0000 > 0000140 e5f4 49f4 34e8 0000 0002 0007 ffff ffff > 0000160 e5f4 49f4 34f6 0000 0000 0000 0000 0000 > > I've extracted this from the backup of the dead machine's /etc/X11/xorg.conf: > > Section "InputDevice" > Identifier "Griffin Powermate" > Driver "evdev" > #Option "Device" > "/dev/input/by-id/usb-Griffin_Technology__Inc._Griffin_PowerMate-event-misc" > Option "Name" "Griffin PowerMate" > Option "SendCoreEvents" "true" > Option "DIALRelativeAxisButtons" "4 5" > EndSection > > Note the use of Option Name and the commented-out Option Device; I > recall that it took me a while to get that stuff right. I believe that > was working with the Debian package xserver-xorg-input-evdev 1.1.2-1. > > On the substitute machine I have xserver-xorg-input-evdev 1:2.0.8-1. > "man evdev" does not mention "Option Name" and I have the impression > that it has gone; when I use that config fragment as-is I get an error > in the log saying that I haven't specified a device [sorry, I can't get > the exact message now without restarting X]. If I use the Option > Device line (or Option Path) I instead get this: > > (**) Griffin Powermate: always reports core events > (**) Griffin Powermate: Device: > "/dev/input/by-id/usb-Griffin_Technology__Inc._Griffin_PowerMate-event-misc" > (WW) Griffin Powermate: Don't know how to use device > (II) UnloadModule: "evdev" > (EE) PreInit returned NULL for "Griffin Powermate" > > So, what does "Don't know how to use device" mean?
This means that the evdev driver didn't recognize it to be either a pointer, a keyboard or a touchscreen during it's probing routine. Looking at a photo online, I can't really tell how you'd classify it, but there could certainly be bugs in the detection logic. If you have the source, take a look in src/evdev.c:EvdevProbe. -- Dan _______________________________________________ xorg mailing list xorg@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/xorg