Arch Linux

ANOKNUSA

Member

Registered: 2010-10-22

Posts: 2,141

[SOLVED] My Touchpad is Possessed...

Howdy ha, folks.  I just installed Arch a couple weeks ago and I gotta say, it's the best distro I've found since leaving Ubuntu a few moths back (I've tried close to a dozen or so).  I'm liking this simplicity/transparency/DIY/built-from-the-ground-up-just-how-you-like-it approach. I've just about got everything tweaked, but the solution to one problem still eludes me: my synaptics touchpad frequently (but oddly, not always) emulates a middle-click when I tap it.  It pastes text, opens unnecessary browser tabs, closes important ones, etc.  For clarification, I'm using KDE 4.5.2, and haven't tried out any other DE's.  I'll post my xorg.conf.d files for you, but there's practically nothing there; I've also tried using synaptiks, with no luck.  Thanks a lot in advance for any help.

*10-evdev.conf*

#
# Catch-all evdev loader for udev-based systems
# We don't simply match on any device since that also adds accelerometers
# and other devices that we don't really want to use. The list below
# matches everything but joysticks.

Section "InputClass"
        Identifier "evdev pointer catchall"
        MatchIsPointer "on"
        MatchDevicePath "/dev/input/event*"
        Driver "evdev"
EndSection

Section "InputClass"
        Identifier "evdev keyboard catchall"
        MatchIsKeyboard "on"
        MatchDevicePath "/dev/input/event*"
        Driver "evdev"
EndSection

*10-synaptics.conf*

Section "InputClass"
        Identifier "touchpad catchall"
        Driver "synaptics"
        MatchIsTouchpad "on"
          Option "TapButton1" "1"
          Option "TapButton2" "2"
EndSection

Last edited by ANOKNUSA (2010-11-05 19:19:33)

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ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 19,772

Re: [SOLVED] My Touchpad is Possessed...

You are using KDE.  I assume you are running hald.

Is there a file in /etc//X11/xorg.conf.d that pertains to Synaptics? (My system has a file 10-synaptics.conf) Do they conflict?

try lshal | less and search the output for words like 'touch'.  Look in the associated section for the parameters of your touchpad and see if they match what you expect.

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rwd

Member

Registered: 2009-02-08

Posts: 664

Re: [SOLVED] My Touchpad is Possessed...

You might also take a look at  https://wiki.archlinux.org/index.php/Touchpad_Synaptics

ANOKNUSA

Member

Registered: 2010-10-22

Posts: 2,141

Re: [SOLVED] My Touchpad is Possessed...

I have looked at the wiki, and actually (sorry about this) the posted 10-synaptics.conf was my backup file.  I ended up changing the last line to Option "TapButton2" "3", to emulate a right-click on two-finger-tap; the behavior is the same, though, with a single tap occasionally emulating a right-click.  I'll check out the hal configuration when I get home.

EDIT: Quickly ran lshal | grep -i touch; here's the output...

info.capabilities = {'input', 'input.touchpad'} (string list)
  info.product = 'SynPS/2 Synaptics TouchPad'  (string)
  input.product = 'SynPS/2 Synaptics TouchPad'  (string)

Last edited by ANOKNUSA (2010-11-03 15:02:49)

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hokasch

Member

Registered: 2007-09-23

Posts: 1,461

Re: [SOLVED] My Touchpad is Possessed...

Sounds like a problem with multi-finger-press emulation. If your touchpad can't detect multiple fingers, synaptics tries to guess from the touched size if one or more finger is on the pad. I had similar problems and just turned off emulation, but you can correct it by setting different thresholds (haven't looked into it, check synaptics documentation and/or google for how to refine emulate two finger taps).

Could you post the output of

sudo dmesg | grep Synaptics

and

evtest /dev/input/eventX

where the X is your touchpad identifier (dmesg will tell you)? evtest is in the Aur.

P.S. if you paste command output/config files, please use the code tags.

Last edited by hokasch (2010-11-03 15:31:46)

ANOKNUSA

Member

Registered: 2010-10-22

Posts: 2,141

Re: [SOLVED] My Touchpad is Possessed...

@hokasch-Sure thing:

 "sudo dmesg | grep Synaptics"

Synaptics Touchpad, model: 1, fw: 7.2, id: 0x1c0b1, caps: 0xd04731/0xa40000/0xa0000
input: SynPS/2 Synaptics TouchPad as /devices/platform/i8042/serio1/input/input7 

There's a problem, however:

 ~]$ evtest /dev/input/input7
evtest: No such file or directory 

I just installed evtest from AUR; even checked that it was executable and reboot the machine, just to be sure.

Last edited by ANOKNUSA (2010-11-03 18:19:18)

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hokasch

Member

Registered: 2007-09-23

Posts: 1,461

Re: [SOLVED] My Touchpad is Possessed...

evtest: No such file or directory

Hmm, input7 somehow is not the right device then. Nevermind, you have the exact same touchpad model than I have. It definitely uses emulation (per default since the last version I think). So best look at the emulate finger taps options (man synaptics) or turn it off completely.

/some background:
Thing is, these touchpads (7.2 +) do supports multifinger natively, but they are one of the newer models that also have multitouch support and the drivers are not yet ready to use either on these models - even the hardware supports it, the kernel can't see it. It is a known problem and first patches exist (leaked out of Novell, see mailing list ), but apparently multitouch is a bit of a headache to implement and nothing has shown up in the tree yet AFAIK.

Discussion about multitouch support on xorg-devel:
http://lists.x.org/archives/xorg-devel/ … 13809.html
Bug Reports:
https://bugs.freedesktop.org/show_bug.cgi?id=28167
https://bugzilla.kernel.org/show_bug.cgi?id=16041
https://bugs.launchpad.net/xorg-driver- … bug/308191

Last edited by hokasch (2010-11-03 19:33:18)

ANOKNUSA

Member

Registered: 2010-10-22

Posts: 2,141

Re: [SOLVED] My Touchpad is Possessed...

Seems my inputs in /dev/input are listed as "event x. Strange. Anyway, thanks for the info; for now, I'll just disabled it, as it certainly isn't necessary.  I actually was aware that full multi-touch wasn't available in the driver, but not that the touchpad itself supported it ( I take "full multi-touch" to mean in the style of Mac touchpads?).  I'll have to keep an eye on that in the future ( I seem to recall the Ubuntu devs saying they were trying to patch the driver for the near future...).  Thanks for the help;  I'll give this a quick test when I get home, and then mark this as solved.

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