For note to @tdawson, I've noted in the rebase request for CentOS Stream 9 (RHBZ#2004309) that we need it for KDE Plasma and I've filed a request for CentOS Stream 8 (RHBZ#2010444) to have it upgraded there.

@rdieter We'll probably want to get libinput upgraded in Fedora Linux 34 as well, right? It's currently at libinput 1.18.x as well.

what exactly requires libinput 1.19 though? The mail on the list is a bit sparse. We only added hold gestures and high-resolution scrolling in terms of new features, but both are backwards compatible - if you're running against an older libinput you just never see the events. you can ifdef out the code or just ship and build against a 1.19.x copy of the libinput.h header.

The current minimum version of libinput in KDE Plasma is 1.14, so I imagine there's quite a bit more cruft they want to get rid of by raising the minimum from 1.14 to 1.19. That and those two features you're talking about are things that PC enthusiasts tend to want and KDE Plasma has a bunch of work going on to make Plasma better for the Steam Deck and related things.

There's also Plasma Mobile and such which also depends on kwin, and that's a lot of touch and gesture stuff.

In regards to older versions, F34 and RHEL8 specifically - I'm very hesitant to update those. I'll be working on getting it into RHEL9 though.

There have been a number of regressions reported with the new high-resolution scroll wheel patches and so far most have been in (X11) applications. For both F34 and RHEL8 it's unlikely those applications will get updated, so we'd be breaking such applications without a solution to the user to fix it.

Having said that, this can be avoided by just updating libinput and leaving the xorg-x11-drv-libinput package as-is because it'll simply prevent the use of the new features in X.

what exactly requires libinput 1.19 though?

We'd like to add support for hold gestures (+ hi-res scrolling once libwayland is released with relevant changes). If shipping 1.19 is not an option, we can add some ifdef guards though.

I think it's a safer bet to ifdef it out for now. The API is still quite new so bugs are expected but from a code perspective it is purely additive, so the ifdefs are quite well-contained.

ftr, I've pushed 1.19 to F34 today but I won't be updating the xorg driver there, so unless you make use of the new features through Wayland, libinput on F34 will look unmodified.

That's fine with me, since KDE Plasma defaults to Wayland in F34+.

Unfortunately, per the CentOS Stream 8 bug (RHBZ#2010444), we're not going to get a libinput update. @tdawson, if there isn't any ifdef logic for this in the Plasma 5.24 code, we're probably going to need to add it.

Thanks for the heads up.
It looks like the package that will need to be watched is kwin.
When we get to that package on the upgrade, I will work on the ifdef stuff.

This appears to be done @ngompa - https://src.fedoraproject.org/rpms/libinput

Can this be closed?

This is now in @tdawson's hands to work out what we need to do for KDE in EPEL.

Interesting timing on this. I was just going through a rebuild of what's currently on F36 (actually epel9-next) on epel8, and libinput is what I just hit.

In short:
epel9/RHEL9 - done
epel8/RHEL8 - not happening.

I'm going to see if it's possible for me to work around this on epel8. We'll see.
But I think since this issue was for updating libinput specifically, we're done with that.

Just to let people know, I've made progress in epel8 with a work-around patch.
The libinput 1.19 feature that is in kwin is hold gestures.

The new hold gesture types are when holding one or more fingers on a touchpad without significant movement. Hold gestures can be used for hold-to-click and other triggers.

I have patched that feature out of the kwin 5.24.5 that is going into epel8-next (and then epel8).

One it is built and in epel8-next, I will close this ticket.

@tdawson Did you manage to pull that off?

The answer is yes: https://src.fedoraproject.org/rpms/kwin/blob/epel8-next/f/kwin-5.24.5-allow-older-libinput.patch

Closing.