I use `xrandr --output LVDS1 --rotate inverted` to rotate the contents of my screen by 180 degrees as part of my thinkpad-scripts. This has worked well until Kubuntu 14.10. Now it still works when I have an external screen (DP2) attached.
I just tried it out now without an external screen attached. The screen turns black, but I can still see the mouse cursor. The cursor also changes according to the program that it is on, one just does not see the program. I can also click and it will have some effect.
To see the screen again, I do [Ctrl][Alt][F1] and then [Ctrl][Alt][F7]. Somebody else has the same ThinkPad X220 with Ubuntu (not sure the version, though) but uses Unity. He has the exact same problem, so this is not bound to KDE or Unity, but fundamental to something that `xrandr` does.
ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: x11-xserver-utils 7.7+2ubuntu2
ProcVersionSignature: Ubuntu 3.19.0-15.15-generic 3.19.3
Uname: Linux 3.19.0-15-generic x86_64
ApportVersion: 2.17.2-0ubuntu1
Architecture: amd64
CurrentDesktop: KDE
Date: Tue May 5 13:48:54 2015
InstallationDate: Installed on 2014-10-07 (209 days ago)
InstallationMedia: Kubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.1)
SourcePackage: x11-xserver-utils
UpgradeStatus: Upgraded to vivid on 2015-04-29 (5 days ago)
I have a ThinkPad X230T running 15.04 with Unity. I confirm that thinkpad-rotate flip causes the screen to go black with just the cursor visible and responsive to the window it's over (albeit with stylus input inverted relative to the screen). ctrl+alt+F1 then ctrl+alt+F7 serve to restore the windows (and stylus input is correct relative to the screen after this).
I would be happy to run any tests if it would be useful to diagnosing and fixing this bug.