Unable to wake up monitor after it goes to sleep (after locking x session, for example)

[JoseO]

Additional info:

lsb_release:
Description: Ubuntu 16.04.1 LTS
Release: 16.04

I'm using an external monitor attached via VGA (seen as DP2 in xrandr output) in an extended desktop configuration (not cloned). Whenever the X session starts some kind of screen saving (for example, after locking the screen), the external monitor and the laptop screen both go to a saving power state.

After that, If I try to wake them up (moving cursor, touch keys, etc.), only the laptop's panel goes back. The external monitor stays in a suspended state. If I force it to wake up and scan inputs, it doesn't find any, and it doesn't appear as conencted in xrandr otput.

The only way I've found to wake it up is by performing the following sequence of operations:

ALT+F1 [switch to first tty/console] --> this does wake up and activate the monitor, mirroring
login as my user
$ xrandr -d :0 #DP2 still doesn't appear
logout
ALT+F7 [go back to X]

At this point, the external monitor is working and X detects it and re-enables the extended desktop

Doing just ALT+F1/ALT+F7, doesn't work (I need to execute xrandr in order to make the whole thing work)

Doing xrandr from the graphical environment (directly in a xterminal in the Xsession) doesn't wake up the monitor

Looks like there's no need to add any addictional operation/parameter to xrandr in order to make this process work, no need to set output settings, etc. Just issue "xrandr -d :0" and things magically work

Thanks in advance

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: xorg 1:7.7+13ubuntu3
ProcVersionSignature: Ubuntu 4.4.0-62.83-generic 4.4.40
Uname: Linux 4.4.0-62-generic x86_64
NonfreeKernelModules: zfs zunicode zcommon znvpair zavl
.tmp.unity_support_test.0:

ApportVersion: 2.20.1-0ubuntu2.5
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
Date: Tue Feb 14 10:54:19 2017
DistUpgraded: Fresh install
DistroCodename: xenial
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation Sky Lake Integrated Graphics [8086:1916] (rev 07) (prog-if 00 [VGA controller])
   Subsystem: Hewlett-Packard Company Skylake Integrated Graphics [103c:8079]
MachineType: HP HP EliteBook 840 G3
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.4.0-62-generic root=ZFS=rpool/ROOT/ubuntu ro boot=zfs quiet splash vt.handoff=7
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/22/2016
dmi.bios.vendor: HP
dmi.bios.version: N75 Ver. 01.05
dmi.board.name: 8079
dmi.board.vendor: HP
dmi.board.version: KBC Version 85.61
dmi.chassis.asset.tag: 5CG6247TWJ
dmi.chassis.type: 10
dmi.chassis.vendor: HP
dmi.modalias: dmi:bvnHP:bvrN75Ver.01.05:bd03/22/2016:svnHP:pnHPEliteBook840G3:pvr:rvnHP:rn8079:rvrKBCVersion85.61:cvnHP:ct10:cvr:
dmi.product.name: HP EliteBook 840 G3
dmi.sys.vendor: HP
version.compiz: compiz 1:0.9.12.2+16.04.20160823-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.67-1ubuntu0.16.04.2
version.libgl1-mesa-dri: libgl1-mesa-dri 11.2.0-1ubuntu2.2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 11.2.0-1ubuntu2.2
version.xserver-xorg-core: xserver-xorg-core 2:1.18.4-0ubuntu0.2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.1-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.7.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20160325-1ubuntu1.2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.12-1build2
xserver.bootTime: Tue Feb 14 10:49:09 2017
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 5312
 vendor CMN
xserver.version: 2:1.18.4-0ubuntu0.2

[Launchpad Janitor (janitor)]

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

[Paul White (paulw2u)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. We are sorry that we do not always have the capacity to review all reported bugs in a timely manner.

Ubuntu 16.04 (xenial) reached end-of-standard-support on April 29, 2021.

I'm setting the status of this bug to 'Incomplete' as it's not seen any activity for some time. If this is still an issue when using a currently maintained release of Ubuntu then please let us know which one(s) otherwise this bug report can be left to expire in approximately 60 days time.

[Launchpad Janitor (janitor)]

[Expired for xorg (Ubuntu) because there has been no activity for 60 days.]