Please try the patch mentioned here: https://bugs.launchpad.net/bugs/1308105
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1581302 Title: Monitor remains blanked with Intel Graphics Status in lightdm package in Ubuntu: Confirmed Bug description: Running on a NUC5i7RYH, latest BIOS. ASUS Monitor connected via Display Port or HDMI Running Xubuntu 16.04 - latest all current patches Sometimes the monitor remains blanked even when the session has reactivated. I have been able to reproduce this problem by letting the monitor remain in the 'blanked' state for > 60 minutes, or powering off the monitor. When the monitor is powered back on and the session is woken up with mouse or keyboard input, it does wake up but the monitor remains blanked. I was able to prove to myself the session was awake by leaving it with terminal opened to full screen with VIM running on an NFS mounted file system. I could type and save at the black monitor screen and see that the file got updates from a different system. So the session is "live" but the computer has forgotten to re-establish the DisplayPort link. An error appears in the lightdm logs about setting a CRTC, if you activate an alternate terminal (say with CTL-ALT-F1) and try `xrandr --output DP1 --auto` it also registers that CRTC error. HOWEVER, if you ssh in from a different machine, tell bash to export DISPLAY=:0 (set $DISPLAY to ':0') and then type 'xrandr --output DP1 --auto' the screen turns on again! This also happens on a Gigabyte BRIX system (same NUC reference design but in that case a core i3 rather than a Core i7). To reproduce, turn off the monitor, wait an hour, and turn it on again. You can also kill HUP the lightdm process and that will restart a new session (but open windows in the previous session are lost). So interesting questions, why does typing xrandr "locally" give you the error but running it from an ssh session work? Since xrandr and restarting the session can both "fix" the problem, the driver seems to know how to turn the display on if told correctly. How can I find out where the code is getting the CRTC error? ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: lightdm 1.18.1-0ubuntu1 ProcVersionSignature: Ubuntu 4.4.0-22.39-generic 4.4.8 Uname: Linux 4.4.0-22-generic x86_64 ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 CurrentDesktop: XFCE Date: Thu May 12 20:33:01 2016 InstallationDate: Installed on 2016-05-08 (4 days ago) InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) LightdmDisplayLog: (II) AIGLX: Suspending AIGLX clients for VT switch LightdmLog: [+80180.09s] DEBUG: Seat seat0 changes active session to [+80189.53s] DEBUG: Seat seat0 changes active session to 64 [+80222.67s] DEBUG: Seat seat0 changes active session to c4 [+80222.67s] DEBUG: Session c4 is already active SourcePackage: lightdm UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1581302/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
