unattended gesture feature

[sancelot]

Hi,
I have a got a touchscreen plugged in .
Altough I have no gesture enabled , sliding cursor from top screen to bottom it applies an unattended gesture reducing window size.

here is a video : https://drive.google.com/file/d/1vLRCZrHLXDZgBQXIjcqqeha4ouNmfL6q/view?usp=sharing

Regards,
S.Ancelot

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: gnome-shell 3.36.9-0ubuntu0.20.04.2
ProcVersionSignature: Ubuntu 5.13.0-27.29~20.04.1-generic 5.13.19
Uname: Linux 5.13.0-27-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.21
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Fri Jan 21 08:59:06 2022
DisplayManager: gdm3
InstallationDate: Installed on 2021-06-30 (204 days ago)
InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
RelatedPackageVersions: mutter-common 3.36.9-0ubuntu0.20.04.2
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)

[Daniel van Vugt (vanvugt)]

Thanks for the bug report. It looks like the touchscreen thinks either a button is held down or a finger is touching the screen during the downward cursor movement.

Please try running 'sudo evtest' in a separate window to log all the touchscreen events, and see if you can find evidence of the kernel thinking that is the case. If so then this should be reassigned to the kernel (if not a hardware problem).

[sancelot (sancelot)]

here is evtest output

esting ... (interrupt to exit)
Event: time 1642755262.678951, type 3 (EV_ABS), code 0 (ABS_X), value 431
Event: time 1642755262.678951, type 3 (EV_ABS), code 1 (ABS_Y), value 960
Event: time 1642755262.678951, -------------- SYN_REPORT ------------
Event: time 1642755262.679902, type 4 (EV_MSC), code 4 (MSC_SCAN), value 90001
Event: time 1642755262.679902, type 1 (EV_KEY), code 330 (BTN_TOUCH), value 1
Event: time 1642755262.679902, -------------- SYN_REPORT ------------
Event: time 1642755262.847941, type 3 (EV_ABS), code 0 (ABS_X), value 430
Event: time 1642755262.847941, -------------- SYN_REPORT ------------
Event: time 1642755262.866962, type 3 (EV_ABS), code 0 (ABS_X), value 429
Event: time 1642755262.866962, -------------- SYN_REPORT ------------
Event: time 1642755262.891943, type 3 (EV_ABS), code 0 (ABS_X), value 428
Event: time 1642755262.891943, -------------- SYN_REPORT ------------
Event: time 1642755262.897943, type 3 (EV_ABS), code 0 (ABS_X), value 429
Event: time 1642755262.897943, -------------- SYN_REPORT ------------
Event: time 1642755262.910925, type 3 (EV_ABS), code 0 (ABS_X), value 428
Event: time 1642755262.910925, -------------- SYN_REPORT ------------
Event: time 1642755263.109964, type 3 (EV_ABS), code 1 (ABS_Y), value 959
Event: time 1642755263.109964, -------------- SYN_REPORT ------------
Event: time 1642755263.116945, type 3 (EV_ABS), code 1 (ABS_Y), value 958
Event: time 1642755263.116945, -------------- SYN_REPORT ------------
Event: time 1642755263.122936, type 3 (EV_ABS), code 1 (ABS_Y), value 956
Event: time 1642755263.122936, -------------- SYN_REPORT ------------
Event: time 1642755263.134942, type 3 (EV_ABS), code 1 (ABS_Y), value 954
Event: time 1642755263.134942, -------------- SYN_REPORT ------------
Event: time 1642755263.153955, type 3 (EV_ABS), code 1 (ABS_Y), value 953
Event: time 1642755263.153955, -------------- SYN_REPORT ------------
Event: time 1642755263.159942, type 3 (EV_ABS), code 1 (ABS_Y), value 952
Event: time 1642755263.159942, -------------- SYN_REPORT ------------
Event: time 1642755263.166955, type 3 (EV_ABS), code 0 (ABS_X), value 429
Event: time 1642755263.166955, type 3 (EV_ABS), code 1 (ABS_Y), value 951
Event: time 1642755263.166955, -------------- SYN_REPORT ------------
Event: time 1642755263.172942, type 3 (EV_ABS), code 1 (ABS_Y), value 949
Event: time 1642755263.172942, -------------- SYN_REPORT ------------
Event: time 1642755263.184940, type 3 (EV_ABS), code 0 (ABS_X), value 430
Event: time 1642755263.184940, type 3 (EV_ABS), code 1 (ABS_Y), value 948
Event: time 1642755263.184940, -------------- SYN_REPORT ------------
Event: time 1642755263.197919, type 3 (EV_ABS), code 1 (ABS_Y), value 947
Event: time 1642755263.197919, -------------- SYN_REPORT ------------
Event: time 1642755263.203967, type 3 (EV_ABS), code 0 (ABS_X), value 431
Event: time 1642755263.203967, type 3 (EV_ABS), code 1 (ABS_Y), value 945
Event: time 1642755263.203967, -------------- SYN_REPORT ------------
Event: time 1642755263.209920, type 3 (EV_ABS), code 1 (ABS_Y), value 944
Event: time 1642755263.209920, -------------- SYN_REPORT ------------
Event: time 1642755263.216921, ...

[Daniel van Vugt (vanvugt)]

Thanks. It looks to me that there is a phantom touch event at the start of the gesture. So gnome-shell is behaving correctly:

Event: time 1642755262.679902, type 1 (EV_KEY), code 330 (BTN_TOUCH), value 1

This means it is either a kernel bug or a hardware fault relating to the touchscreen.

[Daniel van Vugt (vanvugt)]

What is the model of touchscreen? Is it visible when you run 'lsusb'?

[sancelot (sancelot)]

this touchscreen uses a penmount driver. (https://www.salt.com.tw/en/service-support/downloads/software/#)

product : https://www.nexcom.com/Products/industrial-computing-solutions/panel-pc/applied-panel-pc/industrial-touch-screen-monitor-appd-1901t#

lsusb reports it :
us 003 Device 003: ID 14e1:6000 Dialogue Technology Corp.

We will try a touchscreen with an egalax driver asap.