button bindings suddently wrong on Tablet monitor xinput ID 21827,71

[Holger Apfel]

after the last apt-get upgrade the button bindings on my UC-logic tablet monitor are all messed up.
The pens have 2 buttons plus the (pressure sensitive) tip which were assigned to left (tip), right (lower) and mouse wheel (upper button).
Now the upper button is assigned to the same function as the pen tip and can't be changed any more.
evtest shows that the upper button triggers an event 256: BTN_0 while the tip produces an event 330: BTN_TOUCH (and a #24:ABS_PRESSURE) and the lower button an event 331:BTN_STYLUS

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: xinput 1.6.1-1
ProcVersionSignature: Ubuntu 3.19.0-42.48~14.04.1-generic 3.19.8-ckt10
Uname: Linux 3.19.0-42-generic x86_64
.tmp.unity.support.test.0:

ApportVersion: 2.14.1-0ubuntu3.19
Architecture: amd64
CompizPlugins: [core,composite,opengl,compiztoolbox,decor,vpswitch,snap,mousepoll,resize,place,move,wall,grid,regex,imgpng,session,gnomecompat,animation,fade,unitymtgrabhandles,workarounds,scale,expo,ezoom,unityshell]
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
CurrentDmesg: Error: command ['sh', '-c', 'dmesg | comm -13 --nocheck-order /var/log/dmesg -'] failed with exit code 1: comm: /var/log/dmesg: Permission denied
Date: Tue Jan 12 21:00:32 2016
DistUpgraded: Fresh install
DistroCodename: trusty
DistroVariant: ubuntu
GraphicsCard:
 Advanced Micro Devices, Inc. [AMD/ATI] Bonaire XTX [Radeon R7 260X] [1002:6658] (prog-if 00 [VGA controller])
   Subsystem: PC Partner Limited / Sapphire Technology Device [174b:e258]
InstallationDate: Installed on 2015-10-31 (73 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
MachineType: Gigabyte Technology Co., Ltd. To be filled by O.E.M.
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.19.0-42-generic.efi.signed root=UUID=6f849773-e7cd-4229-a720-1cf5423efe4e ro quiet splash vt.handoff=7
SourcePackage: xinput
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/23/2012
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: F4
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: H61MA-D2V
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: To be filled by O.E.M.
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.chassis.version: To Be Filled By O.E.M.
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrF4:bd03/23/2012:svnGigabyteTechnologyCo.,Ltd.:pnTobefilledbyO.E.M.:pvrTobefilledbyO.E.M.:rvnGigabyteTechnologyCo.,Ltd.:rnH61MA-D2V:rvrTobefilledbyO.E.M.:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvrToBeFilledByO.E.M.:
dmi.product.name: To be filled by O.E.M.
dmi.product.version: To be filled by O.E.M.
dmi.sys.vendor: Gigabyte Technology Co., Ltd.
version.compiz: compiz 1:0.9.11.3+14.04.20150313-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.60-2~ubuntu14.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri N/A
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx N/A
version.xserver-xorg-core: xserver-xorg-core N/A
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A
version.xserver-xorg-video-intel: xserver-xorg-video-intel N/A
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau N/A
xserver.bootTime: Tue Jan 12 19:39:57 2016
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.version: 2:1.17.1-0ubuntu3.1~trusty1
xserver.video_driver: radeon