Bug 101339

Created attachment 131789 [details]
scroll.evemu

I notice taps are often ignored.

In another thread (https://bugs.freedesktop.org/show_bug.cgi?id=99447), I described the problem. Peter Hutterer suggested might link to e80873ca6fad5aa and I could make a new report. Perhaps you can tell me what to do:)

If finger hits bottom-left touchpad click "button", it seems always to register.   Taps on other part of pad are not. I cannot say that the ignored clicks are firmer, faster, or different.  I am generally not conscious of how my hand moves while typing until a click is missed. 

I notice this since installing Ubuntu 17.04.  I did not notice problem before. 

libinput-1.6.3. 

Device: Dell Precision 5510.

Maybe libinput is not the problem.  This is a laptop with which I've had more-or-less continuous trouble with ports, video, and devices since I got it in June, 2016. In a previous bug report, Peter fixed problem but mentioned that he was surprised that a brand new laptop like this was (in 2016) had this particular (seemingly out-of-date) touchpad device.

Touchpad measurement: 10.5cm x 8cm

My kernel is off the standard:

$ uname -a
Linux delllap-16 4.10.0-20-generic #22+lp1674838v201705030839 SMP Wed May 3 13:41:02 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

This machine had the bug that would cause system freezes (https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1674838). That is why I'm running this non-standard kernel. I think I noticed the touchpad problem before the kernel problem, but cannot say for sure.  This kernel does fix the system freeze problem, though, and that's a higher priority than missed clicks:)

Other info I think you want:

$ cat /sys/class/dmi/id/modalias
dmi:bvnDellInc.:bvr1.2.25:bd05/07/2017:svnDellInc.:pnPrecision5510:pvr:rvnDellInc.:rn0N8J4R:rvrA01:cvnDellInc.:ct9:cvr:

$ sudo udevadm info /sys/class/input/event7
P: /devices/platform/i8042/serio1/input/input6/event7
N: input/event7
E: DEVNAME=/dev/input/event7
E: DEVPATH=/devices/platform/i8042/serio1/input/input6/event7
E: EVDEV_ABS_00=::42
E: EVDEV_ABS_01=::43
E: EVDEV_ABS_35=::42
E: EVDEV_ABS_36=::43
E: ID_BUS=i8042
E: ID_INPUT=1
E: ID_INPUT_TOUCHPAD=1
E: ID_INPUT_TOUCHPAD_INTEGRATION=internal
E: LIBINPUT_DEVICE_GROUP=11/2/7/1b1:isa0060/serio1
E: LIBINPUT_MODEL_SYNAPTICS_SERIAL_TOUCHPAD=1
E: LIBINPUT_MODEL_TOUCHPAD_VISIBLE_MARKER=1
E: MAJOR=13
E: MINOR=71
E: SUBSYSTEM=input
E: USEC_INITIALIZED=2544176

Will attach scroll.evemu. I think it is more difficult to produce this problem when I'm explicitly trying to produce it, but I did trigger a missed tap after a few tries.

Tell me what other information helps you.