Power Suspend Issue on HP EliteBook 840 G6 Notebook & 18.04

[Ian A. Taylor]

Sir/Madam

I have a  HP EliteBook 840 G6 Notebook onto which I have installed 
Ubuntu 18.04

However when I try a power suspend I cannot wake up the laptop

(Unless I hard power cycle it)

The system is running

Ubuntu 18.04.4 LTS ; kernel 5.3.0-45-generic

In my journal I do see a line

[drm:intel_mst_disable_dp [i915] *ERROR* failed to update payload -22


an lspci -nnk | grep -i vga -A3 returns

00:02:0 VGA compatible controller [0300] Intel Corporation Device 
[8086:3ea0] (rev 02)

              Susbsystem: Hewlett-Packard Company Device [103c:9549]

              Kernel driver in use : i915

              Kernel modules: i915


ubuntu-drivers devices returns

modalias    : pci:v00008086d00002723sv00008086sd00000084bc02sc80i00

vendor        : Intel Corporation

manual_install    : True

driver         : backport-iwlwifi-dkms - distro free


Does anybody know of a solution to this issue ?


Thanking you.

Yours sincerely



Ian Taylor
University of St.Andrews,
School of Physics & Astronomy,
North Haugh,
St.Andrews,
Fife  KY16 9SS,
Scotland.

e-Mail :- iat at st-and.ac.uk
Tel    :- (0)1334-463141
Fax    :- (0)1334-463104

The University of St Andrews
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