Touchpad is not recognized
Solution 1:
After some more research I've found a solution which is described in this thread in German.
You have to add i8042.reset i8042.nomux i8042.nopnp i8042.noloop to the kernel boot options. You can do this permanently by adding these arguments to the GRUB_CMDLINE_LINUX_DEFAULT attribute in the file /etc/default/grub.
Then it looks like this.
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i8042.reset i8042.nomux i8042.nopnp i8042.noloop"
After that you just need to enter this command and reboot:
sudo update-grub