Monitor on Lenovo dock not detected after Suspend

[S Birbalta]

What I do:
Lenovo x250 is connected to Lenovo dock where an additional monitor is connected. I only use the external.
Then I close the lid, take the laptop off the dock and use it a few minutes later just fine.
Then I return back home, connect the laptop to the dock again with closed lid. I press the dock's power button to wake it up. External monitor does not react.
When I open the lid, the internal monitor is on, I can not switch to the external monitor in system settings, it is not detected in "xrandr --query".

Ubuntu 16.04.1
xorg: 1:7.7+13ubuntu3

Would be nice if you guys can help. Thanks.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: xorg 1:7.7+13ubuntu3
ProcVersionSignature: Ubuntu 4.4.0-28.47-generic 4.4.13
Uname: Linux 4.4.0-28-generic x86_64
.tmp.unity_support_test.0:

ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
BootLog: [ 9.228976] rc.local[1043]: * Starting crypto disk...
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: Fri Jul 22 14:23:04 2016
DistUpgraded: Fresh install
DistroCodename: xenial
DistroVariant: ubuntu
DkmsStatus:
 virtualbox, 5.0.24, 4.4.0-28-generic, x86_64: installed
 virtualbox, 5.0.24, 4.4.0-31-generic, x86_64: installed
EcryptfsInUse: Yes
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation Broadwell-U Integrated Graphics [8086:1616] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Lenovo Broadwell-U Integrated Graphics [17aa:2226]
InstallationDate: Installed on 2016-05-24 (59 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
MachineType: LENOVO 20CLS41500
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-28-generic root=UUID=9f9a0e4b-b36a-456a-be5e-e5e00a4d1a0b ro quiet splash
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 02/26/2016
dmi.bios.vendor: LENOVO
dmi.bios.version: N10ET42W (1.21 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20CLS41500
dmi.board.vendor: LENOVO
dmi.board.version: Not Defined
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrN10ET42W(1.21):bd02/26/2016:svnLENOVO:pn20CLS41500:pvrThinkPadX250:rvnLENOVO:rn20CLS41500:rvrNotDefined:cvnLENOVO:ct10:cvrNone:
dmi.product.name: 20CLS41500
dmi.product.version: ThinkPad X250
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.12.2+16.04.20160714-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.67-1ubuntu0.16.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri 11.2.0-1ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 11.2.0-1ubuntu2
version.xserver-xorg-core: xserver-xorg-core 2:1.18.3-1ubuntu2.2
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
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.12-1build2
xserver.bootTime: Mon Jul 18 21:16:45 2016
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 1079
 vendor LGD
xserver.version: 2:1.18.3-1ubuntu2.2

[S Birbalta (s-birbalta)]

The issue is still reproducible with the updated BIOS and I have discovered another, more severe issue. Steps to reproduce:

1. work with internal and and external monitor connected to dock and both switched on and in use.
2. detach the laptop from the dock physically. Internal monitor stays on, WIFI switches on, so undocking is detected by the system.
3. re-attach the open/switched on laptop to the dock. Power button blinks two times (signal for detecting the dock). Both monitors stay black and after about half a minute the system reboots.

Output of your command:
N10ET44W (1.23 )
07/13/2016

[penalvch (penalvch)]

S Birbalta, in order to allow additional upstream developers to examine the issue, at your earliest convenience, could you please test the latest upstream kernel available from http://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D ? Please keep in mind the following:
1) The one to test is at the very top line at the top of the page (not the daily folder).
2) The release names are irrelevant.
3) The folder time stamps aren't indicative of when the kernel actually was released upstream.
4) Install instructions are available at https://wiki.ubuntu.com/Kernel/MainlineBuilds .

If testing on your main install would be inconvenient, one may:
1) Install Ubuntu to a different partition and then test this there.
2) Backup, or clone the primary install.

If the latest kernel did not allow you to test to the issue (ex. you couldn't boot into the OS) please make a comment in your report about this, and continue to test the next most recent kernel version until you can test to the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this issue is fixed in the mainline kernel, please add the following tags by clicking on the yellow circle with a black pencil icon, next to the word Tags, located at the bottom of the report description:
kernel-fixed-upstream
kernel-fixed-upstream-X.Y-rcZ

Where X, and Y are the first two numbers of the kernel version, and Z is the release candidate number if it exists.

If the mainline kernel does not fix the issue, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-X.Y-rcZ

Please note, an error to install the kernel does not fit the criteria of kernel-bug-exists-upstream.

Also, you don't need to apport-collect further unless specifically requested to do so.

It is most helpful that after testing of the latest upstream kernel is complete, you mark this report Status Confirmed.

Lastly, to keep this issue relevant to upstream, please continue to test the latest mainline kernel as it becomes available.

Thank you for your help.

[Launchpad Janitor (janitor)]

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