I have Dell vostro 1510 with Arch installation. the touchpad is not detected in xinput or lspci or libinput list-devices results. used to work before on 5.9.2 kernel. have the same problem with Debian since 5.10 kernel. I downgraded to kernel 5.9.2 for now and it's working there.
Created attachment 296415 [details]
output of "less /proc/bus/input/devices"
Created attachment 296417 [details]
output of "sudo libinput list-devices"
Created attachment 296419 [details]
output of xinput
I tried doing these below to see if it gets fixed but the problem was still there
1-using synaptics and evdev instead of libinput
2-using "modprobe -r psmouse" and "modprobe psmouse"
the only thing that fixes the problem is downgrading the kernel
I also tried reloading i2c_hid module. it still doesn't fix the problem. Also tried to see if any modules are getting blocked during the boot process. but there were no problems there.
+1 with Dell Latitude 7420
Kernel 5.11 does not recognize Dell Touchpad
Kernel 4.18 works
Also fails with 5.12.2-1.el8.elrepo.x86_64