Three-finger-tap for middle mouse button often registers twice

ngoonee · 2017-11-07 19:16:36

Main issue here is that my touchpad does two middle-clicks when I do a three-finger-tap (most of the time). xev shows two indistinguishable events except for the time:-

ButtonPress event, serial 31, synthetic NO, window 0x2200001,
    root 0x125, subw 0x0, time 1152592, (761,491), root:(762,534),
    state 0x0, button 2, same_screen YES

ButtonRelease event, serial 31, synthetic NO, window 0x2200001,
    root 0x125, subw 0x0, time 1152592, (761,491), root:(762,534),
    state 0x200, button 2, same_screen YES

ButtonPress event, serial 31, synthetic NO, window 0x2200001,
    root 0x125, subw 0x0, time 1152640, (761,491), root:(762,534),
    state 0x0, button 2, same_screen YES

ButtonRelease event, serial 31, synthetic NO, window 0x2200001,
    root 0x125, subw 0x0, time 1152640, (761,491), root:(762,534),
    state 0x200, button 2, same_screen YES

Obviously this is annoying, as middle-click to paste pastes twice, and middle-click in browsers to open links in tabs opens two tabs per link.

I'm using libinput, and one odd thing is that Xorg.0.log shows the 'SynPS/2 Synaptocs TouchPad' device being loaded twice. This may be tangential to the issue, as only middle click shows twice on xev (single tap and two-finger tap don't)

$ grep -e "Using input driver" /var/log/Xorg.0.log
[   603.802] (II) Using input driver 'libinput' for 'Power Button'
[   603.822] (II) Using input driver 'libinput' for 'Video Bus'
[   603.862] (II) Using input driver 'libinput' for 'Video Bus'
[   603.902] (II) Using input driver 'libinput' for 'Power Button'
[   603.923] (II) Using input driver 'libinput' for 'HP Wide Vision HD Camera: HP Wi'
[   603.975] (II) Using input driver 'libinput' for 'AT Translated Set 2 keyboard'
[   604.002] (II) Using input driver 'libinput' for 'SynPS/2 Synaptics TouchPad'
[   604.042] (II) Using input driver 'libinput' for 'SynPS/2 Synaptics TouchPad'
[   604.081] (II) Using input driver 'libinput' for 'HP Wireless hotkeys'
[   604.122] (II) Using input driver 'libinput' for 'HP WMI hotkeys'

However journalctl -xe shows it only once

$ journalctl -xe | grep -i synaptics
Nov 08 02:50:38 ngoonee-envy kernel: psmouse serio1: synaptics: queried max coordinates: x [..5656], y [..4768]
Nov 08 02:50:38 ngoonee-envy kernel: psmouse serio1: synaptics: queried min coordinates: x [1284..], y [1120..]
Nov 08 02:50:38 ngoonee-envy kernel: psmouse serio1: synaptics: Your touchpad (PNP: SYN3257 PNP0f13 ETD0000) says it can support a different bus. If i2c-hid and hid-rmi are not used, you might want to try setting psmouse.synaptics_intertouch to 1 and report this to linux-input@vger.kernel.org.
Nov 08 02:50:38 ngoonee-envy kernel: psmouse serio1: synaptics: Touchpad model: 1, fw: 8.16, id: 0x1e2b1, caps: 0xf00123/0x840300/0x12e800/0x400000, board id: 3384, fw id: 2600802
Nov 08 02:50:38 ngoonee-envy kernel: input: SynPS/2 Synaptics TouchPad as /devices/platform/i8042/serio1/input/input7

Trilby mentioned in a recent related thread that /var/log is no longer used by XOrg, but this is a new laptop that I set up 2 weeks ago, and I can confirm that the Xorg.0.log file is updated every boot. Using lightdm if that matters.

Scratching my head on this one, any help appreciated.

seth · 2017-11-07 22:34:53

I don't think it's somehow detected multiple times, but you can check xinput on this.
Does this also happen with the synaptics driver?
Libinput has a bounce filter since 1.9, but it's hardcoded to a 12ms interval (whereas you've 48ms between the clicks)

Could this be a matter of "clumsy tapping", ie. can you reproduce if you try to tap as robotic as possible (stiff fingers and fast and brief contact)?
How constant is the delay between the events?

OT: Afaik atm only gdm stores the xorg log in the journal, rootless Xorg server store logs in your $HOME dir

ngoonee · 2017-11-09 02:07:33

seth wrote:

I don't think it's somehow detected multiple times, but you can check xinput on this.
Does this also happen with the synaptics driver?
Libinput has a bounce filter since 1.9, but it's hardcoded to a 12ms interval (whereas you've 48ms between the clicks)
Could this be a matter of "clumsy tapping", ie. can you reproduce if you try to tap as robotic as possible (stiff fingers and fast and brief contact)?
How constant is the delay between the events?
OT: Afaik atm only gdm stores the xorg log in the journal, rootless Xorg server store logs in your $HOME dir

xinput list shows it only once.

My physical tap is only once, as I actually leave my finger on the touchpad for a short while before raising it. The fact that it only happens intermittently is also annoying since the same motion can generate two or one event.

I'm not using gdm though, am on lightdm....

seth · 2017-11-09 07:31:45

seth wrote:

an you reproduce if you try to tap as robotic as possible (stiff fingers and fast and brief contact)?
How constant is the delay between the events?

ngoonee · 2017-11-09 10:55:55

Fast and brief contact seems to help, yes. The delay is not constant, but definitely longer than 12ms. I'll seek out a way to change the debouncing limit then.

EDIT: Not surprisingly.... there's no way to configure the debouncing delay.

Last edited by ngoonee (2017-11-09 11:42:21)

guraltsev · 2018-04-08 14:15:20

So there is really no way to increase the debounce time? I renders the simulated middle click on my touchpad very difficult to use. Any suggestions? Is there maybe a separate filter one can install?

Could

AUR (en) - xf86-input-evdev-debounce - Arch Linux

help? I did not really understand what it does and how to configure it.

Arch Linux

#1 2017-11-07 19:16:36

Three-finger-tap for middle mouse button often registers twice

#2 2017-11-07 22:34:53

Re: Three-finger-tap for middle mouse button often registers twice

#3 2017-11-09 02:07:33

Re: Three-finger-tap for middle mouse button often registers twice

#4 2017-11-09 07:31:45

Re: Three-finger-tap for middle mouse button often registers twice

#5 2017-11-09 10:55:55

Re: Three-finger-tap for middle mouse button often registers twice

#6 2018-04-08 14:15:20

Re: Three-finger-tap for middle mouse button often registers twice

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