[Dell Latitude E7240] Alps Touchpad acts erratically when multi-touch is vertical, not horizontal

[Mark Smith]

I'm on a Dell Latitude E7240 running 12.04 LTS and my touch pad acts erratically. It happens because my middle and ring fingers accidentally touch the top edge of the pad while my pointer finger is moving the cursor. I can reproduce this on purpose by running "xinput --test [device number]" and watching the events while I do the following:
- Touch the pad near the middle or bottom. The cursor moves slightly as my finger wiggles around.
- Without removing the first finger, touch the pad again with a second finger above the first finger. The cursor shoots up to a[1]=0 (which is the y position).
- Without removing the first finger, remove the second (top) finger. The cursor shoots back down to a[1]=<some large number> Sometimes it takes it all the way to the bottom of the screen, sometimes it goes back to where it was, or somewhere else. I haven't been able to figure out how it decides what to go back to.

With this, while I touching with my pointer finger and my middle or ring finger accidentally touch the pad at the top, the cursor shoots where I don't want it. Then when my middle/ring finger leaves the pad (usually because I started cursing (get it?) at my cursor), it shoots back down again somewhere completely arbitrary.

Similarly:
- Touch the bad near the top.
- Without removing the top finger, touch somewhere near the bottom. The cursor doesn't (yet) move.
- Lift the top finger. The cursor shoots to the bottom.
- Put down the top finger again, without lifting the bottom. The cursor shoots back up again.

You can make the cursor shoot up and down just by keeping your bottom finger down and tapping the top finger. The cursor follows the top finger no matter what you do.

Interestingly, this does NOT happen from side-to-side. Two touches side-by-side trigger the multi-touch gestures and don't move the cursor.

This problem does not happen in Windows 7.

---
AlsaVersion: Advanced Linux Sound Architecture Driver Version k3.13.0-29-generic.
ApportVersion: 2.0.1-0ubuntu17.6
Architecture: amd64
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 1: PCH [HDA Intel PCH], device 0: ALC292 Analog [ALC292 Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: mrksmith 2576 F.... pulseaudio
 /dev/snd/controlC0: mrksmith 2576 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'HDMI'/'HDA Intel HDMI at 0xf7e34000 irq 64'
   Mixer name : 'Intel Haswell HDMI'
   Components : 'HDA:80862807,80860101,00100000'
   Controls : 21
   Simple ctrls : 3
Card1.Amixer.info:
 Card hw:1 'PCH'/'HDA Intel PCH at 0xf7e30000 irq 65'
   Mixer name : 'Realtek ALC292'
   Components : 'HDA:10ec0292,102805ca,00100001'
   Controls : 28
   Simple ctrls : 13
DistroRelease: Ubuntu 12.04
HibernationDevice: RESUME=UUID=303359b5-1c66-468d-935e-a6d9bc56e4e9
MachineType: Dell Inc. Latitude E7240
MarkForUpload: True
Package: linux (not installed)
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 SHELL=/bin/bash
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.13.0-29-generic root=/dev/mapper/vg0-root ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 3.13.0-29.53~precise1-generic 3.13.11.2
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-29-generic N/A
 linux-backports-modules-3.13.0-29-generic N/A
 linux-firmware 1.79.14
Tags: precise running-unity
Uname: Linux 3.13.0-29-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dialout lpadmin plugdev sambashare sudo
dmi.bios.date: 02/18/2014
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A08
dmi.board.asset.tag: 1201037379
dmi.board.name: 0531FD
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.asset.tag: 1201037379
dmi.chassis.type: 9
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA08:bd02/18/2014:svnDellInc.:pnLatitudeE7240:pvr01:rvnDellInc.:rn0531FD:rvrA00:cvnDellInc.:ct9:cvr:
dmi.product.name: Latitude E7240
dmi.product.version: 01
dmi.sys.vendor: Dell Inc.

[penalvch (penalvch)]

Mark Smith, thank you for reporting this and helping make Ubuntu better. Could you please execute the following in a terminal:
apport-collect 1328313

[Mark Smith (mrksmith)]

apport information

[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

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[Mark Smith (mrksmith)]

That what you needed? I got the following errors on the console, so I'm not sure whether you got the data you were looking for.

mrksmith@mrksmith-laptop:~$ apport-collect 1328313
The authorization page:
 (https://bla bla bla)
should be opening in your browser. Use your browser to authorize
this program to access Launchpad on your behalf.
Press any key to continue or wait (5) seconds...
Waiting to hear from Launchpad about your decision...
No packages found matching linux.
ERROR: hook /usr/share/apport/general-hooks/cloud_archive.py crashed:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/apport/report.py", line 719, in add_hooks_info
    symb['add_info'](self, ui)
  File "/usr/share/apport/general-hooks/cloud_archive.py", line 18, in add_info
    if '~cloud' in packaging.get_version(package) and \
  File "/usr/lib/python2.7/dist-packages/apport/packaging_impl.py", line 95, in get_version
    raise ValueError('package does not exist')
ValueError: package does not exist
mrksmith@mrksmith-laptop:~$

[penalvch (penalvch)]

Mark Smith, could you please advise on what happened/s when using Windows with the same scenario?

[Mark Smith (mrksmith)]

I just confirmed on a coworker's laptop, same hardware but with Windows 7, does not have this problem.

[penalvch (penalvch)]

Mark Smith, just to focus the scope, I have a similar laptop touchpad design, and using my right hand, I move the cursor with my index, scroll on the right-hand side with the middle, and primary click with my thumb.

When I am moving the cursor with my index, my middle is either hovering on slightly raised portion beyond the touchpad at the top. My thumb would rest on the primary click. With this method of use, I don't have any stray clicks, or mis-movements.

Given this, I would expect non-desirable behavior if I have three fingers not quite altogether on the touchpad, in Windows, Ubuntu, or Mac.

Could you please re-word the one specific problem here, and is their a configuration one would do in Windows that either minimizes or eliminates what you are referring to here?

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]