linux-surface
[SB3, SG2] Erratic Button/Eraser Signals After Pen Release
I originally filed this issue in linux-surface/linux-surface/issues/1606 but it seems most appropriate here.
- Hardware: Surface Book 3, Surface Go 2, RENAISSER Raphael 520C USB-C Stylus for Surface
- Software: iptsd 3.0 on Fedora 40/41 (GNOME), Ubuntu 20.04/20.10 (GNOME), Debian 12 (KDE)
Stylus functionality was absolutely solid until the latest iptd 3.0 had been installed on my Nobara 40 (Fedora) system running GNOME 46. Moving non-CSD windows with the stylus will render the next stylus input null (but tapping the screen with the stylus for a null input will reset the stylus to normal operation). Drag-and-dropping layers in Krita would lock the stylus pointer in the middle of the operation, requiring clicking the mouse and pressing the ESC key to free the stylus (see screenshot below).
It should be noted that a vanilla Fedora Workstation 40-1.14 with the standard linux-surface packages and iptsd downgraded to 1.4 or 2.0 is BUG FREE. The bugs begin to appear as the entire system is upgraded to the latest versions.
Since then, I've tested various distributions and DE's, and all have exhibited similar buggy behavior. I'll briefly list my experiences:
- Debian 12 (KDE): Same Krita bugs, but this time I noticed that clicking on the desktop invokes middle-click on pen release (middle-click pastes cursor-selection clipboard data as a new sticky note). This middle-click activation slightly moves the canvas while drawing. Also, I had noticed that the Eraser tool gets invoked after lifting the stylus, which flickers the eraser icon.
- Ubuntu 24.04/24.10 (GNOME): All the same bugs mentioned, including middle-click, eraser tool activation.
- Fedora 41 (GNOME): Same bugs mentioned at the start with Nobara/Fedora 40, plus eraser tool activation, but this time there is a primary click activation upon pen release, which produces dots at the end of ordinary brush strokes (see screenshot below).
After testing various distros, I have reverted to Fedora 40 Workstation (GNOME) since the bugs are the least egregious, since I can downgrade iptsd to version 2.0 and not encounter the Eraser tool activation bug.
I always have the opportunity to test stylus functionality in Fedora 41 thanks to Timeshift, so I'll be on the lookout for any changes as more updates become available.
I am experiencing the same issues while trying out the linux surface kernel on a SP7 for the first time. I have a fresh installation of Kubuntu 24.10 running and can't really use the stylus this way. Is there something we can do to help debugging/fixing this issue?
I'm seeing similar with Ubuntu 24.04.2 on a SP7 (using a Renaisser Raphael 520). If I have Button 1 set to Right Mousebutton Click and Button 2 to Middle Mousebutton Click in the Wacom Tablet settings, I will frequently get an unintentional right-button event after tapping with the pen (also in Krita, Button 2 will activate the eraser, not Mouse 3). If I swap them I won't get the false right-clicks, and Button 1 will do Middle Mouse and Button 2 will do nothing in Krita.
Is there a guide to downgrade IPTSD?
[edit]After playing around a bit more it seems like my issue has something to do with the button remapping. If I set both Button 1 and Button 2 to Left Mousebutton, I get no false right-clicks when tapping, and button 1 is ACTUALLY middle mouse, and button 2 is eraser.
Seems like button remapping is just kind of broken? I've tried to use evtest to figure out what the button events are, but it's not really working. I can see that the pen has BTN_TOOL_PEN, BTN_TOOL_RUBBER, BTN_TOUCH, and BTN_STYLUS, but no events are being logged when I press anything.
[edit2]Turns out I was looking at the wrong input in evtest. Should've been looking at IPTSD Virtual Stylus, not Stylus
I can confirm this bug in iptsd 3.0.1. Nearly 50% of cases, releasing the stylus triggers button 2 press & release. Downgrading to 2-1 solves the problem.
Surface Pro 7+, Kubuntu 24.04, Linux 6.16.9-surface-1
To downgrade, dpkg -i iptsd_2-1_amd64.deb and then apt-mark hold iptsd to disable upgrades.
