Re: synaptics vs libinput and GNOME 3.20 no longer supporting synaptics
On 11/07/16 16:34, Raphael Hertzog wrote:
> [ Bcc debian-x and debian-gtk-gnome, discussion on -devel as the topic
> crosses the boundaries of multiple teams ]
> it has been some time that GNOME 3.20 users have been unable to configure
> their touchpad because:
> 1/ xserver-xorg-input-synaptics cherry-picked an upstream commit
> that gives the priority to the synaptics driver to handle touchpads
> 2/ xserver-xorg-input-synaptics is always installed as a dependency
> of xserver-xorg-input-all
> 3/ gnome-control-center 3.20 uses libinput and no longer support synaptics
> Clearly points 1 and 2 are in conflict: the upstream explanation is that that the
> package should not be installed by default and we do install it by default.
> Looking at https://anonscm.debian.org/cgit/pkg-xorg/debian/xorg.git I see
> that we have unreleased changes to not install the synaptics driver by
> default. Timo or Emilio, can you upload those changes?
That would break non-GNOME installations as you said. We should find a good
solution before breaking more stuff.
> Even with this driver no longer installed by default, this will not fix
> the setup for users who are upgrading. Do you have any suggestion on how
> we should handle upgrades?
> My best idea right now is that gnome-control-center's postint should
> do something like this:
> if [ -e /usr/share/X11/xorg.conf.d/60-libinput.conf ] && \
> dpkg -s xserver-xorg-input-synaptics >/dev/null 2>&1 && \
> [ ! -e /etc/X11/xorg.conf.d/90-libinput.conf ]
> echo "Creating /etc/X11/xorg.conf.d/90-libinput.conf to workaround xserver-xorg-input-synaptics"
> mkdir -p /etc/X11/xorg.conf.d
> ln -sf /usr/share/X11/xorg.conf.d/60-libinput.conf /etc/X11/xorg.conf.d/90-libinput.conf
> The other solution is to add a "Conflicts: xserver-xorg-input-synaptics"
> but this is rather extreme. Although it is somewhat in line with
> the upstream views on the topic.
Not that either.
> The best solution would be to have gnome-control-center handle properly
> synaptics-managed touchpads but I don't think that upstream developers are
> very open to that idea given that they have dropped the support on
> What do you think?
We thought about backporting synaptics support back for Stretch, to give more
time to libinput to mature and to other DEs to add support for it. Not sure how
much work that would be though.
The other good option I can think of is to make GNOME prefer libinput by passing
some options to X through gdm. No idea how feasible that is.