On Sun, 2018-06-03 at 09:35 +1000, Peter Hutterer wrote: > On 2/6/18 19:53 , Timur Kristóf wrote: > > On Sat, 2018-06-02 at 14:14 +1000, Peter Hutterer wrote: > > > On 1/6/18 22:50 , Timur Kristóf wrote: > > > > On Thu, 2018-05-31 at 13:44 -0700, Laura Abbott wrote: > > > > > On 05/24/2018 04:13 PM, Timur Kristóf wrote: > > > > > > Hi, > > > > > > > > > > > > On the XPS 13 9360 and 9370 xinput sees two touchpads > > > > > > instead > > > > > > of > > > > > > one: > > > > > > ⎡ Virtual core > > > > > > pointer id=2 [master > > > > > > pointer (3)] > > > > > > ⎜ ↳ Virtual core XTEST > > > > > > pointer id=4 [slave pointer (2)] > > > > > > ⎜ ↳ DELL07E6:00 06CB:76AF > > > > > > Touchpad id=12 [slave pointer (2)] > > > > > > ⎜ ↳ SynPS/2 Synaptics > > > > > > TouchPad id=17 [slave pointer (2)] > > > > > > > > > > > > dmesg also gives me the following: > > > > > > > > > > > > [ 1.429811] psmouse serio1: synaptics: Your touchpad > > > > > > (PNP: > > > > > > DLL07e6 > > > > > > PNP0f13) 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@xxxxxxxxxxxxxxx. > > > > > > > > > > > > The Dell one is the real touchpad, the other one is an > > > > > > artifact > > > > > > of > > > > > > the > > > > > > psmouse driver. Weird touchpad freezes and jittering issues > > > > > > can > > > > > > be > > > > > > observed when both of these devices are there. The general > > > > > > advice > > > > > > on > > > > > > the web is to blacklist the psmouse driver. (This is also > > > > > > published > > > > > > by > > > > > > Dell as a .deb package which contains a config file doing > > > > > > just > > > > > > this.) > > > > > > > > > > > > However, on Fedora I cannot blacklist the psmouse driver > > > > > > because it > > > > > > is > > > > > > compiled built-in instead of as a module. Could you guys > > > > > > change > > > > > > the > > > > > > Fedora kernel config to compile it as a module instead? > > > > > > > > > > > > Thanks & best regards, > > > > > > Timur > > > > > > > > > > So assuming nobody else has objections, I think it's okay to > > > > > at > > > > > least try this on rawhide and see if it uncovers any other > > > > > problems. > > > > > > > > > > Thanks, > > > > > Laura > > > > > > > > > > > > > Looking into this a bit more, the root cause of this issue is > > > > that > > > > the > > > > touchpad is wired up in such a way that it is accessible on > > > > both > > > > PS/2 > > > > and I2C. I2C is preferred and used by i2c-hid but at the same > > > > time > > > > the > > > > PS/2 interface is also picked up by psmouse. Thus, Xorg sees > > > > the > > > > two > > > > interfaces as two different devices. > > > > > > That is fairly standard and doesn't matter. This was also the > > > case > > > for > > > earlier SMBus implementation but the common thing was that the > > > PS/2 > > > device never actually sent events. So it was only an issue for > > > some > > > tools that expected only one touchpad to exist (e.g. synclient). > > > Check with evemu-record whether the device sends events. if not, > > > then > > > Xorg is definitely not confused by it. If it does and both event > > > nodes > > > send events then yes, we have a kernel bug there. > > > > I've talked to Mario, a developer at Dell, and he pointed me to > > this > > freedesktop bug report: > > https://bugs.freedesktop.org/show_bug.cgi?id=101470 > > > > According to his description, there is actually no input coming > > from > > PS/2 but it is still (wrongly) picked up by syndaemon. To be > > honest, > > I'm not sure if Fedora uses syndaemon (I assume libinput is used > > for > > everything now?), but I can tell that the touchpad does jitter when > > the > > PS/2 device is there. > > syndaemon works in that it monitors the keyboard state (or attaches > to > XRECORD events) and then sets a synaptics-specific property on the > device it attaches to. This means that unless the synaptics driver > is > used, it cannot do anything. Do you have xorg-x11-drv-synaptics- > legacy > installed? If not, then libinput is being used (also: xinput list- > props > <device name> shows the driver name in the property names). No, I don't have the synaptics driver installed. Probably the reason why I was pointed to that bug report is that this laptop is shipped with and old Ubuntu version which still uses it. So it seems that this is a different problem with the same symptoms. > Even if you do have the synaptics driver installed, disabling a > kernel > device that doesn't send events ... well, you can't get less than > "no > events" :) I was pretty convinced that the issue went away after disabling that device, but I might be wrong and it might have just been a coincidence. > > > I can also confirm that evemu-record doesn't see any input coming > > from > > the PS/2 device. > > > > > > Solution would be to somehow remove the psmouse-detected device > > > > node > > > > from the system when i2c-hid detects the same device. Is this > > > > possible? > > > > > > This is more an upstream discussion, CC-ing benjamin for details. > > > > > > I do recommend filing a bug with an evemu recording of a > > > freezing/jittering interaction. Lots of touchpad processing > > > happens > > > in > > > userspace and this could be the cause of pressure thresholds set > > > too > > > high. CC me on that bug and I can have a look. sudo libinput > > > debug-events --verbose will also show extra information including > > > things > > > when a touch ended based on its pressure information. > > > > I can try to reproduce the problem and see if I can make an evemu > > recording. What should I file the bug against (and where)? > > Unfortunately I'm not familiar with the components involved. > > For upstream, this link has everything you need: > https://wayland.freedesktop.org/libinput/doc/latest/reporting_bugs.ht > ml > In the Fedora bugzilla it's the libinput component. Either bugzilla > will > work, it's the same person answering you anyway (i.e. me :) Thanks! > > Searching for libinput in the journal reveals a bunch of touch jump > > messages, which seem to be related to the problem: > > https://paste.fedoraproject.org/paste/MoZGqf25VpHjCLSYzTxdfw > > there are a few issues here. The cursor jump complaint could be the > cause of the jerkiness but we only trigger that when you move >20mm > within one event - not something that can be triggered easily (or at > all) in real life. All the timer offset negative bugs indicate that > your > compositor isn't rendering fast enough and libinput is starved for > attention. That is currently relatively common under Wayland but I > haven't seen this under Xorg yet. That is just a copy-paste from my journal from the past couple of days, and I admit I was running both X and Wayland during that time. (Mostly to investigate whether this-or-that issue is reproducible on X or Wayland.) So some of those messages do come from Wayland actually. > IOW I think we may have a multitude of bugs here that need > untangling > before we can pin down psmouse as real culprit. Looks like this turns out more complicated than I anticipated. What do you think should be the next step in untangling it? Interestingly, the problem seems to be less noticable when running kernel 4.17, compared to 4.16 - but just because I haven't noticed it doesn't mean it's not there. Best regards, Tim _______________________________________________ kernel mailing list -- kernel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to kernel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://getfedora.org/code-of-conduct.html List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/kernel@xxxxxxxxxxxxxxxxxxxxxxx/message/3LN3NY624VFS3BWFK52TNFRSNY5YDPNY/
