Public bug reported:
Hardware:
Intel NUC NUC5i5RYK, Intel HD Graphics 6000, core i5
LG TV, model 47LA6200-UA
Bug is reproducible on demand.
I have the box connected to the TV via HDMI.
Steps to reproduce:
1) Turn on TV
2) Boot into Linux, log into KDE
3) Turn TV off, leave computer running
4) Turn TV back on
5) TV reports no signal for input
At state #5, cannot get the signal back by:
a) shaking mouse,
b) pressing keyboard keys
c) unplugging, then reconnecting, HDMI cable
At state #5:
--login via ssh from remote computer works
--top shows all processes running as typical for KDE
--able to start x11vnc via ssh from remote machine, then connect to display
:0 using KRDC as a client; KDE still works fine
--I can get the signal back by killing X form a local tty, or remotely vis
ssh, in which case X will restart and I will get the signal back until the next
time I turn off the TV, though that requires me to relogin to KDE and start
from scratch as the session isn't saved when you kill X that way.
Workaround (seems to work, at least for cases when TV is off for a few minutes):
--Before shutting of TV, switch to tty1 (Ctrl+Alt+F1)
--Shut off TV
--Turn TV on when you next want to use it
--tty1 will show up, switch to tty7 (vt7), and it works as expected.
--on the prior step a console message is printed:
[timestamp] [drm:gen8_irq_handler [i915]] *ERROR* The master control
interrupt lied (SDE)!
The same message also repeats upon HDMI cable disconnect/reconnect.
I'm currently using the latest Intel drivers from
https://01.org/linuxgraphics but the issue also presents with default
kubuntu drivers.
I suspect the issue has to do with the HDMI handshake not being
renewed/restarted when the TV comes back on. Even when in state #5, the
TV detects when the HDMI cable is unplugged ("No cable connected" vs "No
signal from input").
Let me know if you need any additional information or if I can do
anything to help with debugging.
Thanks!
--Mark
ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: xserver-xorg-core 2:1.17.2-1ubuntu9.1
ProcVersionSignature: Ubuntu 4.2.0-19.23-generic 4.2.6
Uname: Linux 4.2.0-19-generic x86_64
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
Date: Wed Dec 2 16:20:43 2015
ExecutablePath: /usr/bin/Xorg
InstallationDate: Installed on 2015-09-04 (89 days ago)
InstallationMedia: Kubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
ProcEnviron:
PATH=(custom, no user)
LANG=en_US.UTF-8
SourcePackage: xorg-server
UpgradeStatus: Upgraded to wily on 2015-12-01 (1 days ago)
** Affects: xorg-server (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug hdmi intel wily
--
You received this bug notification because you are a member of Ubuntu-X,
which is subscribed to xorg-server in Ubuntu.
https://bugs.launchpad.net/bugs/1522174
Title:
No signal from X Server after turn TV off then back on
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1522174/+subscriptions
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