Let touch screens be used under the Wacom driver

[Till Kamppeter]

I have a Lenovo Thinkpad Twist which is a convertible with touch screen. In tablet mode it should be possible to easily rotate the screen oprientation so that it can be used in both landscape and portrait mode and even without needing to care which edge is at the bottom and which at the top. See bug 1216065 for further information.

To be able to easily rotate the touch screen coordinate system to match the screen content, the touch screen should be run under the wacom driver. In addition, the Wacom driver adds some more gestures to the touch screen.

At least on my Thinkpad Twist the switchover is easy. One only needs to add "|Atmel" to the "MatchProduct" line in the "InputClass" section with Identifier "Wacom class" in /usr/share/X11/xorg.conf.d/50-wacom.conf. See also the attached file.

For a quick test (which survives updates and can easily be undone), copy /usr/share/X11/xorg.conf.d/50-wacom.conf to /etc/X11/xorg.conf.d/50-wacom.conf and edit this file. Restart X by rebooting or restarting lightdm.

What gets added:

- Touch coordinate system rotation (bug 1216065)
- Right-click emulation by holding a finger on the place where the right click should happen and then tapping anywhere else with a second finger, after that sliding the held down first finger to the desired entry of the context menu and releasing there.

What gets lost:

- The three-and four-finger gestures described on https://wiki.ubuntu.com/Multitouch. Bug 1227214 needs to get fixed.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Tyler Ham (tyler.ham)]

I have a Thinkpad T550 running Ubuntu 14.04. I had to use a newer kernel in order to recognize the Wacom touch screen device (see bug 1433444).

With the "wacom" driver, I experience the same as the bug report description: 1- and 2-finger touches work, but three- and four-finger gestures are not available. With the "evdev" driver, three- and four-finger gestures are available, but 2-finger gestures are gone.

The wacom driver, xf86-input-wacom, is supposed to pass 2-finger gestures up to X when they are disabled in the driver (see http://linuxwacom.sourceforge.net/wiki/index.php/Multitouch#Disable_xf86-input-wacom_In-driver_2FGT_Gestures). I tried adding the Option "Gesture" "off" in 50-wacom.conf. With "Gesture" "off" in 50-wacom.conf, the three- and four-finger gestures are back, but the 2-finger gestures are still missing (same behavior as the "evdev" driver).