Bug 1849797

Summary:	ThinkPad T490: Touchpad has incorrect size
Product:	[Fedora] Fedora	Reporter:	Yannick Ihmels <yannick>
Component:	systemd	Assignee:	systemd-maint
Status:	CLOSED ERRATA	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	32	CC:	btissoir, lnykryn, msekleta, peter.hutterer, ssahani, s, systemd-maint, zbyszek
Target Milestone:	---
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
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Fixed In Version:	systemd-245.7-1.fc32	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-07-30 18:56:26 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Yannick Ihmels 2020-06-22 20:05:41 UTC

Description of problem:

On my ThinkPad T490, the mouse cursor moves vertically faster than horizontally when using the touchpad. When I draw a circle with my finger on the touchpad, the cursor moves in a vertical ellipse on the screen.

I think it's because libinput assumes an incorrect size. The command "sudo libinput list-devices" reports a size of 77x107 mm, but I measured with a ruler that it is 100x68 mm (WxH) (NotebookCheck.net measured 100x70 mm [1])

The touchpad didn't work perfectly under Fedora 31 (kernel 5.3.7-301.fc31, libinput 1.14.1-1.fc31) either, but better. The above command reported a size of 70x50 mm there (the ratio of width to height is correct here, which explains why the touchpad worked better then).

[1]: https://www.notebookcheck.net/Lenovo-ThinkPad-T490-i7-MX250-Low-Power-FHD-Laptop-Review.421150.0.html


Version-Release number of selected component (if applicable):

kernel 5.6.19-300.fc32
libinput libinput-1.15.5-1.fc32

Comment 1 Peter Hutterer 2020-06-23 23:59:17 UTC

run the touchpad-edge-detector tool please and paste the full output here, thanks. It's in libevdev-utils.rpm.

Comment 2 Yannick Ihmels 2020-06-24 07:01:50 UTC

Thank you for your answer. I have run the tool with the sizes 77x107mm and 100x68mm.

77x107mm:

    $ sudo touchpad-edge-detector 77x107 /dev/input/event4
    Touchpad SynPS/2 Synaptics TouchPad on /dev/input/event4
    Move one finger around the touchpad to detect the actual edges
    Kernel says:	x [1266..5678], y [1162..4694]
    Touchpad sends:	x [1266..5678], y [1161..4694] \^C

    Touchpad size as listed by the kernel: 77x107mm
    User-specified touchpad size: 77x107mm
    Calculated ranges: 4412/3533

    Suggested udev rule:
    # <Laptop model description goes here>
    evdev:name:SynPS/2 Synaptics TouchPad:dmi:bvnLENOVO:bvrN2IET88W(1.66):bd04/22/2020:svnLENOVO:pn20N3S3GW00:pvrThinkPadT490:rvnLENOVO:rn20N3S3GW00:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:*
     EVDEV_ABS_00=1266:5678:57
     EVDEV_ABS_01=1161:4694:33
     EVDEV_ABS_35=1266:5678:57
     EVDEV_ABS_36=1161:4694:33

100x68mm:

    $ sudo touchpad-edge-detector 100x68 /dev/input/event4
    Touchpad SynPS/2 Synaptics TouchPad on /dev/input/event4
    Move one finger around the touchpad to detect the actual edges
    Kernel says:	x [1266..5678], y [1162..4694]
    Touchpad sends:	x [1266..5678], y [1161..4694] \^C

    Touchpad size as listed by the kernel: 77x107mm
    User-specified touchpad size: 100x68mm
    Calculated ranges: 4412/3533

    Suggested udev rule:
    # <Laptop model description goes here>
    evdev:name:SynPS/2 Synaptics TouchPad:dmi:bvnLENOVO:bvrN2IET88W(1.66):bd04/22/2020:svnLENOVO:pn20N3S3GW00:pvrThinkPadT490:rvnLENOVO:rn20N3S3GW00:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:*
     EVDEV_ABS_00=1266:5678:44
     EVDEV_ABS_01=1161:4694:52
     EVDEV_ABS_35=1266:5678:44
     EVDEV_ABS_36=1161:4694:52

Comment 3 Peter Hutterer 2020-06-24 22:33:12 UTC

Thanks for the logs. Just to confirm - 100x68 is the correct size, right? Because the whole point of this is to correct the wrong kernel size, so measuring it with the wrong size isn't going to help you much ;)

Also, do you happen to still have kernel 5.3.7-301.fc31 around? Would be good to confirm that it was the same (wrong) size back then too to make sure this isn't a kernel regression. You should be able to just install it from koji without breakages (and just booting into a tty to run libinput list-devices is enough anyway).

Comment 4 Yannick Ihmels 2020-06-25 09:19:40 UTC

100 x 68 mm (width x height) is the correct size. I measured it again. :-)

I installed kernel 5.3.7-301.fc31.x86_64 from koji and ran "sudo libinput list-devices". It reported 77x107mm.

Comment 5 Peter Hutterer 2020-06-26 01:35:26 UTC

Oh, turns out this is already upstream in systemd, commits 2ceefe45873d0265fb99bc5757593e5bbb2c732b and cae97f3b60da6bcdd9cc01efe9e6efb7a019ebd6. Punting to systemd for backporting to F32, otherwise the 246 update will fix this automatically.

Comment 6 Zbigniew Jędrzejewski-Szmek 2020-07-27 07:28:22 UTC

Peter, please set POST on bugs which have a patch upstream. This makes them easier to pick out of the long
list of outstanding bugs.

Comment 7 Fedora Update System 2020-07-27 09:52:15 UTC

FEDORA-2020-2faf839786 has been submitted as an update to Fedora 32. https://bodhi.fedoraproject.org/updates/FEDORA-2020-2faf839786

Comment 8 Peter Hutterer 2020-07-27 23:05:00 UTC

oh, I didn't know about this - will do next time.

Comment 9 Fedora Update System 2020-07-28 15:19:34 UTC

FEDORA-2020-2faf839786 has been pushed to the Fedora 32 testing repository.
In short time you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --advisory=FEDORA-2020-2faf839786`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2020-2faf839786

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 10 Fedora Update System 2020-07-30 18:56:26 UTC

FEDORA-2020-2faf839786 has been pushed to the Fedora 32 stable repository.
If problem still persists, please make note of it in this bug report.