Disable touchscreen gesture

[Cyrus Lien]

[Impact]
Wacom touchscreen doesn't works well when in-driver gesture was enabled (lp: 1774242), the issue can be fixed by disabling in-driver gestures for touchscreens.

Config file that instructs driver to disable in-driver gestures for touchscreens:
# Prevent the Wacom driver from providing its own gestures for
# touchscreen devices.
#
Section "InputClass"
 Identifier "Wacom touchscreen gestures"
 MatchDriver "wacom"
 MatchIsTouchscreen "true"
 Option "Gesture" "off"
EndSection

[Test Case]
1) Enable the bionic-proposed repository, and install the xf86-input-wacom package
2) Restart and see if the Wacom touchscreen multi-touch gestures (2-finger zoom/rotate and 3+ finger gestures) work as desired. Also check /var/log/Xorg.0.log to see if Wacom touchscreen using wacom driver instead libinput driver.

[Regression Potential]
Low

[Cyrus Lien (cyruslien)]

debdiff for bionic

[Cyrus Lien (cyruslien)]

Need revert commit 53abe85 for Disco, Eoan and Focal.

[Bin Li (binli)]

I found the upstream fix for this issue. I will verify it.

commit 31a5405f7d9405bc514585709161287b0c67386e
Author: Jason Gerecke <email address hidden>
Date: Mon Sep 9 15:32:17 2019 -0700

    Change default gesture mode: touchpad=on, touchscreen=off

    A large number of users run the GNOME desktop which has its own gesture
    engine that performs actions on touchscreens. These gestures are much
    better than the ones we provide, so lets disable our engine by default
    for touchscreens. Note that GNOME doesn't do anything with touchpad
    gestures, so we leave them enabled by default.

    Note that this change will effectively cause a feature regression for
    users of other environments that do *not* have their own gesture
    engines (Cinnamon, KDE, MATE, XFCE, etc.). Users will want to add an
    xorg.conf.d snippet with `Option "Gesture" "on"` to bring back the
    functionality.

    Signed-off-by: Jason Gerecke <email address hidden>

[Bin Li (binli)]

The patch in commment#3 works fine. So we need SRU this patch.

[Bin Li (binli)]

Here is the patch.

[Bin Li (binli)]

Timo,

 Could you help merge the change-default-gesture-mode.patch into bionic? Thanks!

[Bin Li (binli)]

@Timo,

 I found the xserver-xorg-input-wacom-hwe-18.04 had this patch already. But xserver-xorg-input-wacom didn't have, when I tried to upgrade xserver-xorg-input-wacom-hwe, found it will remove the ubuntu-desktop and old xserver-xorg-* packages.

 So do you have any idea how we fix this issue in OEM image? Thanks!

[Bin Li (binli)]

Here is the original bug.

https://bugs.launchpad.net/ubuntu/+source/xf86-input-wacom/+bug/1774242