Trackpad setup for HiDPI screen

Question

I've just gotten the new Dell XPS 13. I've managed to setup almost everything, except for the touchpad.

If I place the cursor to the left edge of the screen, and start moving my finger to the right, I only get to the middle of the screen before I run out of trackpad. I basically need to find a way to change speed at which the cursor is moving while I move the finger.

I've read what I could find about it, and it more or less says I need to change something using xinput command. I can't however figure out what. Here is xinput list-props output:

xinput list-props 13
Device 'DLL082A:01 06CB:76AF Touchpad':
    Device Enabled (138):   1
    Coordinate Transformation Matrix (140): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
    libinput Tapping Enabled (298): 0
    libinput Tapping Enabled Default (299): 0
    libinput Tapping Drag Enabled (300):    1
    libinput Tapping Drag Enabled Default (301):    1
    libinput Tapping Drag Lock Enabled (302):   0
    libinput Tapping Drag Lock Enabled Default (303):   0
    libinput Tapping Button Mapping Enabled (304):  1, 0
    libinput Tapping Button Mapping Default (305):  1, 0
    libinput Natural Scrolling Enabled (276):   0
    libinput Natural Scrolling Enabled Default (277):   0
    libinput Left Handed Enabled (278): 0
    libinput Left Handed Enabled Default (279): 0
    libinput Accel Speed (280): 0.000000
    libinput Accel Speed Default (281): 0.000000
    libinput Scroll Methods Available (285):    1, 1, 0
    libinput Scroll Method Enabled (286):   1, 0, 0
    libinput Scroll Method Enabled Default (287):   1, 0, 0
    libinput Click Methods Available (306): 1, 1
    libinput Click Method Enabled (307):    1, 0
    libinput Click Method Enabled Default (308):    1, 0
    libinput Middle Emulation Enabled (290):    0
    libinput Middle Emulation Enabled Default (291):    0
    libinput Send Events Modes Available (261): 1, 1
    libinput Send Events Mode Enabled (262):    0, 0
    libinput Send Events Mode Enabled Default (263):    0, 0
    libinput Disable While Typing Enabled (309):    1
    libinput Disable While Typing Enabled Default (310):    1
    Device Node (264):  "/dev/input/event7"
    Device Product ID (265):    1739, 30383
    libinput Drag Lock Buttons (292):   <no items>
    libinput Horizontal Scroll Enabled (293):   1

can anyone help me figure out what I need to change to make the trackpad work properly in HiDPI mode ?

Answer 1

I messed around a bit on my laptop, and I think I found an answer. Try:

xinput --set-prop 13 "libinput Accel Speed" <acceleration_value>

libinput devices are strange in that there doesn't seem to be an actual speed parameter, only an acceleration param which goes from -1 to 1, inclusive. Find a number which works to your liking. As you may know, changes with xinput don't persist past reboots. However, you can make a change permanent by modifying your .xsessionrc file. Try:

echo "xinput --set-prop 13 'libinput Accel Speed' <acceleration_value>" >> ~/.xsessionrc

For what it's worth, Synaptics devices (which is what I have) utilize a "Synaptics Move Speed" property. More information on that here: ftp://www.x.org/pub/X11R7.5/doc/man/man4/synaptics.4.html. Just CTRL+F 'move speed'.