Comment 0 for bug 1803600

When updating from 18.04 to 18.10 on a ThinkPad L480 the Elantech touchpad stopped working. This means it is not recognized at all. This problem occured after the first boot in 18.10

`dmesg | grep -i elantech` shows the following errors:

    [ 3.409043] psmouse serio1: elantech: assuming hardware version 4 (with firmware version 0x5f3001)
    [ 3.427372] psmouse serio1: elantech: Synaptics capabilities query result 0x90, 0x18, 0x10.
    [ 3.447275] psmouse serio1: elantech: Elan sample query result 00, 23, c8
    [ 3.464905] psmouse serio1: elantech: Trying to set up SMBus access
    [ 5.576149] elan_i2c 0-0015: 0-0015 supply vcc not found, using dummy regulator
    [ 5.586505] elan_i2c 0-0015: failed to get resolution: -71
    [ 5.586527] elan_i2c: probe of 0-0015 failed with error -71

uname:

    $ uname -a
    Linux test 4.18.0-10-generic #11-Ubuntu SMP Thu Oct 11 15:13:55 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

I found the following thread which solves the problem temporarly (and reports the same problem in Arch):
https://bugs.archlinux.org/task/59714

Running the following command enables it again for the current session:

    sudo sh -c 'echo -n "elantech"> /sys/bus/serio/devices/serio1/protocol'

dmesg afterwards:

    [ 569.522490] psmouse serio1: elantech: assuming hardware version 4 (with firmware version 0x5f3001)
    [ 569.544584] psmouse serio1: elantech: Synaptics capabilities query result 0x90, 0x18, 0x10.
    [ 569.565939] psmouse serio1: elantech: Elan sample query result 00, 23, c8

Before running the fix:

    $ cat /sys/bus/serio/devices/serio1/protocol
    ETSMBus

and after:

    $ cat /sys/bus/serio/devices/serio1/protocol
    ETPS/2

After reboot the command has to be run again, of course.

ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: xorg 1:7.7+19ubuntu8
ProcVersionSignature: Ubuntu 4.18.0-11.12-generic 4.18.12
Uname: Linux 4.18.0-11-generic x86_64
ApportVersion: 2.20.10-0ubuntu13.1
Architecture: amd64
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: KDE
Date: Thu Nov 15 20:59:36 2018
DistUpgraded: 2018-11-10 09:56:53,358 DEBUG icon theme changed, re-reading
DistroCodename: cosmic
DistroVariant: ubuntu
DkmsStatus:
 virtualbox, 5.2.18, 4.15.0-38-generic, x86_64: installed
 virtualbox, 5.2.18, 4.18.0-10-generic, x86_64: installed
 virtualbox, 5.2.18, 4.18.0-11-generic, x86_64: installed
GraphicsCard:
 Intel Corporation UHD Graphics 620 [8086:5917] (rev 07) (prog-if 00 [VGA controller])
   Subsystem: Lenovo UHD Graphics 620 [17aa:506a]
InstallationDate: Installed on 2018-08-06 (101 days ago)
InstallationMedia: Xubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
MachineType: LENOVO 20LS001AGE
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.0-11-generic root=UUID=a1f97298-a2b8-469d-80ed-eeee7497c6e6 ro quiet splash vt.handoff=1
SourcePackage: xorg
Symptom: display
UpgradeStatus: Upgraded to cosmic on 2018-11-10 (5 days ago)
dmi.bios.date: 02/09/2018
dmi.bios.vendor: LENOVO
dmi.bios.version: R0QET37W (1.14 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20LS001AGE
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40697 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrR0QET37W(1.14):bd02/09/2018:svnLENOVO:pn20LS001AGE:pvrThinkPadL480:rvnLENOVO:rn20LS001AGE:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:
dmi.product.family: ThinkPad L480
dmi.product.name: 20LS001AGE
dmi.product.sku: LENOVO_MT_20LS_BU_Think_FM_ThinkPad L480
dmi.product.version: ThinkPad L480
dmi.sys.vendor: LENOVO
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.95-1
version.libgl1-mesa-dri: libgl1-mesa-dri 18.2.4-0~b~padoka0
version.libgl1-mesa-glx: libgl1-mesa-glx 18.2.4-0~b~padoka0
version.xserver-xorg-core: xserver-xorg-core 2:1.20.1-3ubuntu2.1
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.1.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-3