On ASUS laptop K52JU the touchpad works (two fingers scrolling and two-three fingers buttons emulation, too) but is detected by the kernel as a Logitech mouse and handled by evdev pointer catchall under Xorg. This is bad because you can't change touchpad settings like speed, acceleration, buttons emulation, side scrolling ecc. through Xorg rules files. The touchpad is Elantech.

I read this was a kernel issue that was fixed in 3.3, but for me is still here.
The kernel is configured with Slackware's huge-smp config (almost every driver is selected).

I found this in dmesg:

[12.069781] psmouse serio4: elantech: synaptics_send_cmd query 0x01 failed.


cat /proc/bus/input/devices:

I: Bus=0011 Vendor=0002 Product=0005 Version=0063
N: Name="ImPS/2 Logitech Wheel Mouse"
P: Phys=isa0060/serio4/input0
S: Sysfs=/devices/platform/i8042/serio4/input/input9
U: Uniq=
H: Handlers=mouse0 event9 
B: PROP=0
B: EV=7
B: KEY=70000 0 0 0 0 0 0 0 0
B: REL=103