⎡ Virtual core pointer                      id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ PS/2 Elantech Touchpad                    id=11   [slave  pointer  (2)]
⎜   ↳ ELAN Touchscreen                          id=13   [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)]
    ↳ Power Button                              id=8    [slave  keyboard (3)]
    ↳ Sleep Button                              id=9    [slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard              id=10   [slave  keyboard (3)]
    ↳ Integrated Camera                         id=12   [slave  keyboard (3)]

sudo dkms ldtarball psmouse-elantech-x551c.tar.gz
sudo dkms install -m psmouse -v elantech-x551c
sudo rmmod psmouse
sudo modprobe psmouse