Not able to change acceleration profile

[warptozero]

After installing the driver everything seems to work ok, except that acceleration is forced on. libinput list-devices gives Accel profiles: none instead of Accel profiles: flat *adaptive. So I'm unable to set it to flat.

[warptozero]

Considering this patch has been merged into mainline, is this still the right place to report bugs?

[mwyborski]

@warptozero during merging to mainline we had to remove some offsets. The driver will need a libinput quirks file. As soon as 4.20 is released i will have a look at it. Anyways i had no problem setting or turning off the acceleration, neither with mtrack nor with libinput. Which distro are you using?

[warptozero]

I'm using Arch Linux and I've compiled linux-mainline 4.20rc6 (and rc7) from the AUR. But had the same behavior with 4.19.x and both the module compiled manually and dkms.

Another problem I'm having is that upon resizing windows with the mouse (by holding down a keyboard button) the cursor jumps to the top left corner of the screen. Now this is usually caused by palm detection, however I'm unable to set DisableWhileTyping to false (in a xorg.conf file). As if the trackpad is not providing this option.

The cursor also feels a little laggier then should be, but this might just be the de/acceleration I'm feeling.

Another thing I'm getting is a lot of the following messages in Xorg.0.log:

[  1744.046] (EE) event23 - Apple Inc. Magic Trackpad 2: kernel bug: Touch jump detected and discarded.
See https://wayland.freedesktop.org/libinput/doc/1.12.3/touchpad-jumping-cursors.html for details

[warptozero]

Well I've narrowed down the jumping cursor problem to setting the Coordinate Transformation Matrix with xinput:

xinput set-prop 'Apple Inc. Magic Trackpad 2' 'Coordinate Transformation Matrix' 1 0 0 0 1 0 0 0 -1

Using -1 0 0 0 -1 0 0 0 1 also leads to the same behavior. The reason I'm doing this is that I like to use the trackpad upside down because I find it a lot more ergonomic (the default orientation gives me wrist pain). So far I haven't found an other way to switch orientation.

Would it be possible for the driver to provide an option for this? As it looks like this is a fairly common complaint and Apple provides a way to do this on macOS:

• sudo defaults write com.apple.MultitouchSupport ForceAutoOrientation YES
• Now place the Magic Trackpad in desired orientation on your desk and drop all 5 fingers on it (outstretched towards the edges not scrunched up).
• The coordinates of the trackpad automatically flip so all cursor and gesture motions match the new hand orientation.

[warptozero]

If it's any help, here's the output of xinput list-props:

Device 'Apple Inc. Magic Trackpad 2':
	Device Enabled (143):	1
	Coordinate Transformation Matrix (145):	1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
	libinput Tapping Enabled (279):	1
	libinput Tapping Enabled Default (280):	0
	libinput Tapping Drag Enabled (281):	1
	libinput Tapping Drag Enabled Default (282):	1
	libinput Tapping Drag Lock Enabled (283):	0
	libinput Tapping Drag Lock Enabled Default (284):	0
	libinput Tapping Button Mapping Enabled (285):	1, 0
	libinput Tapping Button Mapping Default (286):	1, 0
	libinput Natural Scrolling Enabled (287):	1
	libinput Natural Scrolling Enabled Default (288):	0
	libinput Scroll Methods Available (289):	1, 1, 0
	libinput Scroll Method Enabled (290):	1, 0, 0
	libinput Scroll Method Enabled Default (291):	1, 0, 0
	libinput Click Methods Available (292):	1, 1
	libinput Click Method Enabled (293):	1, 0
	libinput Click Method Enabled Default (294):	1, 0
	libinput Middle Emulation Enabled (295):	0
	libinput Middle Emulation Enabled Default (296):	0
	libinput Accel Speed (297):	0.000000
	libinput Accel Speed Default (298):	0.000000
	libinput Left Handed Enabled (299):	0
	libinput Left Handed Enabled Default (300):	0
	libinput Send Events Modes Available (264):	1, 0
	libinput Send Events Mode Enabled (265):	0, 0
	libinput Send Events Mode Enabled Default (266):	0, 0
	Device Node (267):	"/dev/input/event3"
	Device Product ID (268):	76, 613
	libinput Drag Lock Buttons (301):	<no items>
	libinput Horizontal Scroll Enabled (302):	1

No manual xinput changes.

And the only xorg.conf.d file that's active for pointers:

Section "InputClass"
    Identifier "libinput magic trackpad"
    MatchIsTouchpad "yes"
    MatchDevicePath "/dev/input/event*"
    MatchProduct "Magic Trackpad"
    Driver "libinput"

    # libinput options
    Option "AccelProfile" "flat"
    Option "NaturalScrolling" "True"
    Option "HorizontalScrolling" "True"
    Option "DisableWhileTyping" "False"
    Option "Tapping" "True"
EndSection

If you like I can also paste the input parts of the Xorg.log.

The following quirks file is active (/etc/libinput/local-overrides.quirks):

[Magic trackpad pressure override quirk]
MatchUdevType=touchpad
MatchName=*Magic Trackpad*

AttrTouchSizeRange=2:1
AttrPalmSizeThreshold=10000
AttrThumbSizeThreshold=8000

AttrPressureRange=1:0
AttrPalmPressureThreshold=3000
AttrThumbPressureThreshold=3000

AttrTouchSizeRange=2:1 and AttrPressureRange=1:0 are needed to make touch pressure normal. The thresholds are set unreasonably high to rule out thumb/palm detection issues for the cursor jump.

[alanorth]

@warptozero are you talking about the "touch jump" error where the cursor gets stuck for a few seconds? I get that a few times a day and the following messages are printed in the system journal:

Dec 18 11:37:38 knafeh /usr/lib/gdm-x-session[805]: (EE) event18 - Apple Inc. Magic Trackpad 2: kernel bug: Touch jump detected and discarded.
Dec 18 11:37:38 knafeh /usr/lib/gdm-x-session[805]: See https://wayland.freedesktop.org/libinput/doc/1.12.3/touchpad-jumping-cursors.html for details
Dec 18 11:37:38 knafeh /usr/lib/gdm-x-session[805]: (EE) event18 - Apple Inc. Magic Trackpad 2: kernel bug: Touch jump detected and discarded.
Dec 18 11:37:38 knafeh /usr/lib/gdm-x-session[805]: See https://wayland.freedesktop.org/libinput/doc/1.12.3/touchpad-jumping-cursors.html for details
Dec 18 11:37:38 knafeh /usr/lib/gdm-x-session[805]: (EE) event18 - Apple Inc. Magic Trackpad 2: kernel bug: Touch jump detected and discarded.
Dec 18 11:37:38 knafeh /usr/lib/gdm-x-session[805]: See https://wayland.freedesktop.org/libinput/doc/1.12.3/touchpad-jumping-cursors.html for details

I usually just wait it out calmly, or turn the touchpad off and back on again. I'm on Arch Linux with kernel 4.19.x with Xorg.

[warptozero]

@alanorth I haven't experienced a stuck cursor since I switched to 4.20, so maybe that could be because of manually compiling or dkms? I also experienced a once every few hours kernel lockup that disappeared with the switch.

To recap everything:

• Can't change acceleration profile
• Cursor jumps to top left corner of screen when Coordinate Transformation Matrix is changed from default (might be a libinput or xorg bug, but could be aleviated by providing an option to change trackpad orientation).
• Large amount of touch jumps detected and discarded when using touchpad normally (with only one finger touching): once or twice every few seconds and almost everytime when setting a finger down. This isn't noticable though but does fill up the logs.