keyboard not working in laptop Fujitsu E5511

[pigs-on-the-swim]

Description: Ubuntu 21.10
Release: 21.10

Keyboard not working on Laptop after booting successful.

Expected: built in keyboard can be used to invoke password

keyboard not working in laptop after booting Ubuntu 21.10
Login not possible, password can not be inserted in GUI (lightdm but can be other like gdm3 or gddm or slim, no impact) because keyboard is not responding at all (not even special keys).

The keyboard is working before boot so grub etc can be controlled.
Hence it is disabled by Ubuntu.
External USB-keyboard is working. Does not make internal keyboard work.

Special:
When the lid is closed and Ubuntu suspends properly and then the lid is opened and Ubuntu resumes properly then the keyboard is working!

This defect is found in all Ubuntu 18, 19, 20, 21 and XUbuntu 18 to 21.10.
Issue does not appear in Ubuntu 22.04 / XUbuntu 22.04.
U 22.04 upgrade is no option due to failing GSM-modem control in all 22.04 versions.

It did NOT HELP to disable intel vbtn -tablet mode by blacklisting intel_vbtn.
Presumably the issue is related to the ill fated "tablet mode"
The machine is Fujitsu E5511.

Can you please point out a workaround to enableth keyboard?

ProblemType: Bug
DistroRelease: Ubuntu 21.10
Package: linux-image-5.13.0-40-generic 5.13.0-40.45
ProcVersionSignature: Ubuntu 5.13.0-40.45-generic 5.13.19
Uname: Linux 5.13.0-40-generic x86_64
ApportVersion: 2.20.11-0ubuntu71.1
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: sysyadmin 1239 F.... pulseaudio
CasperMD5CheckResult: pass
CurrentDesktop: XFCE
Date: Sun Apr 24 11:35:59 2022
InstallationDate: Installed on 2022-04-23 (0 days ago)
InstallationMedia: Xubuntu 21.10 "Impish Indri" - Release amd64 (20211012)
MachineType: FUJITSU CLIENT COMPUTING LIMITED LIFEBOOK E5511
ProcFB: 0 i915drmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.13.0-40-generic root=UUID=deadea51-80db-4ccb-8008-10cbbc002aba ro quiet splash
RelatedPackageVersions:
 linux-restricted-modules-5.13.0-40-generic N/A
 linux-backports-modules-5.13.0-40-generic N/A
 linux-firmware 1.201.5
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/17/2022
dmi.bios.release: 2.28
dmi.bios.vendor: FUJITSU CLIENT COMPUTING LIMITED
dmi.bios.version: Version 2.28
dmi.board.name: FJNB2E8
dmi.board.vendor: FUJITSU CLIENT COMPUTING LIMITED
dmi.board.version: C3
dmi.chassis.type: 10
dmi.chassis.vendor: FUJITSU CLIENT COMPUTING LIMITED
dmi.chassis.version: LIFEBOOK E5511
dmi.modalias: dmi:bvnFUJITSUCLIENTCOMPUTINGLIMITED:bvrVersion2.28:bd03/17/2022:br2.28:svnFUJITSUCLIENTCOMPUTINGLIMITED:pnLIFEBOOKE5511:pvr10601736746:rvnFUJITSUCLIENTCOMPUTINGLIMITED:rnFJNB2E8:rvrC3:cvnFUJITSUCLIENTCOMPUTINGLIMITED:ct10:cvrLIFEBOOKE5511:skuSK01:
dmi.product.family: LIFEBOOK-FTS
dmi.product.name: LIFEBOOK E5511
dmi.product.sku: SK01
dmi.product.version: 10601736746
dmi.sys.vendor: FUJITSU CLIENT COMPUTING LIMITED

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This change was made by a bot.

[pigs-on-the-swim (dw1-4)]

REMARK:
There seems to be a conflict with elan module.
As a successul workaround I disabled the elants_i2c module in grub:

GRUB_CMDLINE_LINUX_DEFAULT="initcall_blaclist=elants_i2c"

This is just a workaround.
However, the internal keyboard seems to work proper in the moment.
No negative impact on loading of touchpad module (sudo modprobe i2c-hid-acpi) which is always necessary to get the touchpad working.