Synaptic touchpad not responding in ubuntu 19.04 when using nvidia drivers

Btw adding synaptic_intertouch=0 to the parameters at boot doesn't change anything.

Oh, and forgot to mention that an external optical usb mouse works just fine.

I just tested against the mainline kernel: 5.1.0-050100rc6-generic #201904211830 SMP Sun Apr 21 18:33:49 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

This didn't work - or rather there was an error building with dkms and nvidia (so actually it works, but that's because I'm back on noveau drivers, which also work on the standard kernel).

I've attached the make.log.

A very similar thing just happened to me, with the 435 drivers via ppa. Reverting to 430 solved it. Ubuntu 19.04, P50. USB mouse works.

Have the same problems on p50 after installing NVIDIA-Linux-x86_64-440.64.
Linux <skipped> 5.3.0-40-generic #32-Ubuntu SMP Fri Jan 31 20:24:34 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

This also happens in 20.04.

Yes. This is still an issue on the P50, same machine as above.
Now on kernel: 5.4.0-21-generic
xserver-xorg-input-libinput v. 0.29.0-1

And I've tested with the 3 different Nvidia drivers listed in the additional drivers interface.
That would be nvidia-drivers:
440.64-0ubuntu3
435.21-0ubuntu7
390.132-0ubuntu2

As before, touchpad and trackpoint work just fine with noveau drivers and mesa.

If you have this error @Simon and @Nikolay, please choose the "This bug affects me" at the top of the page.

I just tested installing the Nvidia binaries directly from the web-site. That did not fix the issue with the non-functional touchpad either.
That was the driver version 440.82

I though I might experiment a little. I installed xubuntu-desktop with the lightdm display manager. Didn't work either. Then I installed kubuntu-desktop with sddm display manger and the suddenly my touchpad started working.
I then did a dpkg-reconfigure gdm3, rebooted and logged back into the "standard" gnome session. And now my touchpad is working with the Nvidia drivers installed and working. I have no clue why but, to resume, there are 2 workarounds:
1: use nouveau drivers instead of nvidia
2: install kubuntu-desktop (and log into ubuntu-desktop or whatever floats your boat).

This also indicates that it's "just" a config issue somewhere.

Ahh. Actually xinput now (with kubuntu-desktop installed) now has registered my touchpad as a standard mouse it seems (I don't have multitouch functionality, so no two-finger scrolling, etc).

$ xinput list
⎡ Virtual core pointer id=2 [master pointer (3)]
⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)]
⎜ ↳ Logitech MX Master id=10 [slave pointer (2)]
⎜ ↳ Logitech K800 id=11 [slave pointer (2)]
⎜ ↳ PS/2 Synaptics TouchPad id=14 [slave pointer (2)]
⎣ Virtual core keyboard id=3 [master keyboard (2)]
    ↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)]
    ↳ Power Button id=6 [slave keyboard (3)]
    ↳ Video Bus id=7 [slave keyboard (3)]
    ↳ Sleep Button id=8 [slave keyboard (3)]
    ↳ Jabra Link 370 id=9 [slave keyboard (3)]
    ↳ Integrated Camera: Integrated C id=12 [slave keyboard (3)]
    ↳ AT Translated Set 2 keyboard id=13 [slave keyboard (3)]
    ↳ ThinkPad Extra Buttons id=15 [slave keyboard (3)]
    ↳ Logitech MX Master id=16 [slave keyboard (3)]
    ↳ Logitech K800 id=17 [slave keyboard (3)]

As can be seen from this:
xinput --list-props 14
Device 'PS/2 Synaptics TouchPad':
        Device Enabled (154): 1
        Coordinate Transformation Matrix (156): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
        libinput Natural Scrolling Enabled (290): 0
        libinput Natural Scrolling Enabled Default (291): 0
        libinput Scroll Methods Available (292): 0, 0, 1
        libinput Scroll Method Enabled (293): 0, 0, 1
        libinput Scroll Method Enabled Default (294): 0, 0, 1
        libinput Button Scrolling Button (295): 2
        libinput Button Scrolling Button Default (296): 2
        libinput Middle Emulation Enabled (297): 0
        libinput Middle Emulation Enabled Default (298): 0
        libinput Accel Speed (299): 0.000000
        libinput Accel Speed Default (300): 0.000000
        libinput Accel Profiles Available (301): 1, 1
        libinput Accel Profile Enabled (302): 1, 0
        libinput Accel Profile Enabled Default (303): 1, 0
        libinput Left Handed Enabled (304): 0
        libinput Left Handed Enabled Default (305): 0
        libinput Send Events Modes Available (275): 1, 0
        libinput Send Events Mode Enabled (276): 0, 0
        libinput Send Events Mode Enabled Default (277): 0, 0
        Device Node (278): "/dev/input/event8"
        Device Product ID (279): 2, 1
        libinput Drag Lock Buttons (306): <no items>
        libinput Horizontal Scroll Enabled (307): 1

So for me the only viable workaround is still to use the nouveau-drivers

Ok. So I finally found a viable workaround (or fix). In BIOS the GPU must be set to "Hybrid Graphics" NOT "Discrete".

This fixed my issues with running nvdia-drivers and using my touchpad at the same time in ubuntu 20.04.

There was a strong recommendation not to change "Hybrid" to "Discrete" mode in BIOS - not sure if it is still a problem, just beware: https://www.reddit.com/r/thinkpad/comments/a2g0k4/warning_do_not_change_from_hybrid_graphics_to/

Thanks Nikolay. I'm not sure that what you link to is related. That sounds much worse. My PC wasn't bricked. I just couldn't use the touchpad if I also chose to install the Nvidia driver.

Status changed to 'Confirmed' because the bug affects multiple users.

I confirm what zob wrote. I switched from Discrete to Hybrid mode in BIOS and now touchpad work fine. I use Nvidia proprietary driver from ubuntu standard repository (440.64), my only problem is screen tearing (PRIME profile set to performance mode). I don't know if the drivers from PPA repository fix touchpad and tearing problem. I read that Nvidia 440.66.11 Linux driver fixes annoying bugs With PRIME Sync: https://www.phoronix.com/scan.php?page=news_item&px=NVIDIA-440.66.11-Linux.
Previously I used the card in discrete mode with Fedora 31 and the proprietary Nvidia drivers 440.82 from RPM Fusion repository without any problems for touchpad or for tearing.

Is there any news about it? Ubuntu 20.04.1, kernel 5.4.0-48, Nvidia CUDA driver 455.23.05, ThinkPad P50, latest BIOS/firmware 1.62, with VGA configured in discrete mode, integrated touchpad do not work.

This issue became apparent after installing Ubuntu 20.04.2 LTS. Switched BIOS to discrete mode and touchpad works.

Just upgraded to 20.10, same story. Works in discreet graphics mode but is having hiccups - sometimes touchpad is not recognized, e.g. sometimes on non-clean reboot, sometimes when reboot with external monitor attached. Intermittent, clean reboot without attached peripherals seems to always help.