The name of the application I use for this is DS4Windows(totally free, no extra crap needed). In order to interact with SW:TOR it must be run as admin. Be sure to set the profile for "Use Touchpad for Swipe controls" and "Use DInput only", so that we can make use of the touchpad. I also highly recommend checking the "Mouse Acceleration" box.
Note that this is a work is progress and subject to interpretation on your part and editing on my part
I have bound the controller as follows:
cross:1, circle:2, square:3, triangle:4.
D-pad: down:5, right:6, left:7, up:8.
share:9, options:0, PS:bab.
Click touchpad: left:-, right:=.
L1:Lshift, R1:Lctrl, L2:RMB, R2:LMB, L3:space, left stick:wasd, right stick:mouse.
Touchpad swipe: up:mouse wheel up, down:mouse wheel down.
Deadzone LS&RS:0.25, Curve LS&RS:15%.
BTW 36 skills(3 hotbars) worth of ability bindings with this setup.