How to switch from libinput to synaptics in Ubuntu 18.04

I had the same problem and basically solved it by following Ryko's advice.

sudo apt install xserver-xorg-input-synaptics

... did the trick. I didn't uninstall libinput like Pilot6 said and libinput is still happily handling my keyboard, etc.

If you're running an HWE release (like 18.04.2) then you'll actually want:

sudo apt install xserver-xorg-input-synaptics-hwe-18.04

You don't need to remove any packages, just add this and once it's active you can make adjustments to your taste. (as others have indicated above)

Hint: The suffix "-hwe-18.04" needs to be appended to any pkg that HWE impacts. Read up on HWE and you'll understand why and the scope of the packages impacted.

can you give instructions on how to do the override?

The synaptics config file can be copied to /etc/X11/xorg.conf.d and given a higher number than the /usr/share/X11/xorg.conf.d synaptics.conf default. Then the synaptics touchpad driver overrides the libinput touchpad driver by having a higher priority.

There is an option that could be added to libinput.conf to prevent the libinput touchpad driver from being considered. After "MatchIsTouchpad" add:

Option "Ignore" "true"

Check with xinput:

xinput list
xinput --list-props "whatever touchpad from above list"

That will show either the libinput or the synaptics properties if the touchpad is using libinput or synaptics respectively. The synaptics touchpad driver should show output something like this:

Device 'ELAN1300:00 04F3:3057 Touchpad':
Device Enabled (152):   1
Coordinate Transformation Matrix (154): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
Device Accel Profile (280): 1
Device Accel Constant Deceleration (281):   1.000000
Device Accel Adaptive Deceleration (282):   1.000000
Device Accel Velocity Scaling (283):    1.000000
Synaptics Edges (284):  0, 3208, 0, 2210
Synaptics Finger (285): 1, 70, 0
Synaptics Tap Time (286):   180
Synaptics Tap Move (287):   171
Synaptics Tap Durations (288):  180, 180, 100
Synaptics ClickPad (289):   1
Synaptics Middle Button Timeout (290):  0
Synaptics Two-Finger Pressure (291):    282
Synaptics Two-Finger Width (292):   7
Synaptics Scrolling Distance (293): 154, 77
Synaptics Edge Scrolling (294): 0, 0, 0
Synaptics Two-Finger Scrolling (295):   1, 0
Synaptics Move Speed (296): 1.000000, 1.000000, 0.000000, 0.000000
Synaptics Off (297):    0
Synaptics Locked Drags (298):   0
Synaptics Locked Drags Timeout (299):   5000
Synaptics Tap Action (300): 0, 0, 0, 0, 0, 0, 0
Synaptics Click Action (301):   1, 3, 2
Synaptics Circular Scrolling (302): 0
Synaptics Circular Scrolling Distance (303):    0.100000
Synaptics Circular Scrolling Trigger (304): 0
Synaptics Circular Pad (305):   0
Synaptics Palm Detection (306): 1
Synaptics Palm Dimensions (307):    10, 200
Synaptics Coasting Speed (308): 20.000000, 50.000000
Synaptics Pressure Motion (309):    30, 160
Synaptics Pressure Motion Factor (310): 1.000000, 1.000000
Synaptics Grab Event Device (311):  1
Synaptics Gestures (312):   1
Synaptics Capabilities (313):   1, 0, 0, 1, 1, 0, 0
Synaptics Pad Resolution (314): 32, 31
Synaptics Area (315):   0, 0, 0, 0
Synaptics Soft Button Areas (316):  1604, 0, 1800, 0, 0, 0, 0, 0
Synaptics Noise Cancellation (317): 50, 50
Device Product ID (276):    1267, 12375
Device Node (275):  "/dev/input/event15"

The synaptics touchpad driver allows for adjusting many settings when the libinput driver just turns a few things on or off and so is not useful for my touchpad.

I ran into problem after installing synaptics touchpad in ubuntu 18.04. My keyboard stopped working. So, I booted into the system (keyboard was working on login screen), mouse was working properly so I opened my mails from the history (I saved the commands in the mails using my mobile), I copied the following commands with enter (empty line after the commands):

sudo apt install xserver-xorg-input-all xserver-xorg-input-synaptics

This fixed boot the keyboard and mouse. No need to remove libinput or anything else. Reboot and everything is working now.

Note: Save the commands with an empty line using enter at the end of commands. This will help commands to execute directly without pressing enter while copy pasting in terminal, if the keyboard is not working.

The problem is not necessarily the missing Synaptics drivers, it is more the fact that the libinput driver settings are purposefully left generic so that the user or hardware OEM can adjust them as desired.

Rather than simply uninstalling libinput and installing Synaptics, you can still add Synaptics but to keep everything working you need to provide an "override" by removing/updating references to libinput specifically in relation to your touchpad ONLY and adding in a rule for Synaptics.

A major part of the problem is that there doesn't appear to be any proper GUI tool and few of the hardware OEMs (Dell/HP/Lenovo/etc) provide customized configs optimized to their hardware outside the possible exception of their own preinstalled Ubuntu versions (Dell provides this option at least). I haven't grabbed the latest Dell Ubuntu image and unpacked it to see if they supply any customizations, but it wouldn't surprise me if they did. If not I definitely think it is something they should see about adding, since the XPS13/XPS15 and their business brothers the Precision 55x0 models are amazingly fast running Ubuntu compared to Windows.

This article by Dell has a good start on how to potentially fix the issue (and doesn't necessarily only apply to their systems or their touchpads), https://www.dell.com/support/article/us/en/19/sln308258/precision-xps-ubuntu-general-touchpad-mouse-issue-fix?lang=en

I am using lubuntu Release 20.04.2 LTS (Focal Fossa) with 64-bit Kernel Linux 5.8.0-63-generic x86_64. My laptop is Dell inspiron i5 3567 I have been using it since a year and was working well, but today I opened my laptop and noticed while on terminal that my up arrow key has been continuously pressed I have never faced such implication, so in a hurry I powered it off and opened laptop's back lid and removed the keyboard and cleaned it (there was too much dirt) after fixing all the screws I booted it again and still the problem was not solved reinstalling the driver which was libinput by default using the command

sudo apt-get install --reinstall xserver-xorg-input-all xserver-xorg-input-libinput

but still nothing fixed, then I thought of using synaptics driver I installed it with

sudo apt-get install xserver-xorg-input-synaptics

then restarted laptop but still nothing fixed then I installed xserver-xorg-core after restarting the problem got fixed, but I noticed my touchpad was using libinput so in

/usr/share/X11/xorg.conf.d

I edited the file 40-libinput.conf and turned off all the MatchIs options to off then restarted the pc and checked the command xinput list now everything was ok my trackpad changed to Synaptics and now my keyboard isn't having any problem.

I experienced a similar issue after trying to solve it for a month, I finally found the workaround: simply remove all libinput (except for libinput-bin and libinput10:amd64) and synaptics related packages and install evdev using the following command:

sudo apt install xserver-xorg-core && xserver-xorg-input-evdev

A complete description in Chinese can be found in my blog: https://zhuanlan.zhihu.com/p/168512118

Note that this obviously did not install synaptics as the title requires. And this solution may break your touchpad (have not fully tested it), but it works extremely well with touchpoint. Hope it helps (as all above solutions didn't actually solve my problem).