input-evdev patch adding option to override XDevice type Atom, option to force EV_REL events being treated as absolute values.

Ville Syrjälä syrjala at
Mon Mar 10 17:11:16 PDT 2008

On Tue, Mar 11, 2008 at 12:51:50AM +0100, Wolfgang Draxinger wrote:
> The other problem I had was, that the 3Dconnextion SpaceNavigator 
> sends relative motion events (already in the USB-HID protocol) and 
> Linux just passes this on. However technically a spaceball is a "6DOF 
> joystick", which generates absolute values. Since the Linux kernel 
> can't tell if the stuff sent by USB-HID devices is what it should be, 
> it's upon the program reading the events (i.e. the X.Org driver), to 
> process them correctly. So another option
> Option "ForceAbsolute" "True|False"
> which will make EV_REL events generate absolute motion events.

Perhaps a quirk in the usbhid driver to fix up the events would be
better. Unless there is some valid reason for interpreting the
events as relative.

Ville Syrjälä
syrjala at

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