touchpad multitouch not working

[vin cen zo]

Hi, I have installed qubes on a dell inspiron 7548 touchscreen, I have several problems with the touchpad. In detail, the problem is to use it with two fingers, the click goes crazy, only the scroll works.

 I actually realized that unlike other even older Dell laptops, this one has buttons under the touchpad, so clicking the left button conflicts as if it were a two-finger click. I don't find how to disable the two finger click, only scrolling is disabled. Also, drag and drop doesn't work for me. On the mouse / touchpad options in xfce's settings manager, I have the selection of two devices: the mouse and the touchpad, both named MSFT0001: 00 06CB: 75BD.

I've done a lot of testing, but I can't fix this problem. It is probably a drive problem perhaps related to the multitouch touchpad. I was unable to disable the multitouch functionality.
The system is up to date. The touchscreen worked during installation like a mouse, now it no longer works. Also, when I launch the lspci command the touchpad and the whole system freezes until the command is finished.

Possible solutions? Is this a bug or an incorrect driver?