Re: request for opinion on synaptics, adb and powerpc

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

On Fri, 2006-01-06 at 23:36 -0500, Dmitry Torokhov wrote:
> On Friday 06 January 2006 23:33, Benjamin Herrenschmidt wrote:
> > 
> > > Why would you want to switch to relative mode when leaving X? As far as
> > > I know the only other mouse "user" out there is GPM and there are patches
> > > available for it to use event device:
> > > 
> > > 	http://geocities.com/dt_or/gpm/gpm.html
> > > 
> > > Unfortunately the maintainer can't find time to merge these so they were
> > > sitting there for over 2 years. FWIW Fedora patches their GPM with these.
> > 
> > gpm among other legacy things ...
> > 
> 
> What other legacy things? And in that case I think manually forcing protocol
> back to relative would be an option.
> 
> The thing is that Synaptics in absolute and relative mode is 2 completely
> different devices with different capabilities. If you want to switch mode
> you really need to kill old input device and create a brand new one.

Ok, so what method should we use to "switch" ? sysfs isn't quite an
option yet as the ADB bus isn't yet represented there (unless we add
attributes to the input object, but that's a bit awkward as it would be
destroyed and re-created if I follow you). A module option would work
but adbhid isn't a module, thus that would basically end up as a static
kernel argument, unless the driver "polls" the module param regulary to
trigger the change.. I don't think there is a way for a driver to get a
callback when /sys/module/<driver>/parameters/* changes is there ?

Ben.