Public bug reported:

After suspend/resume, the Synaptics clickpad reports BTN_LEFT=1 about
one second after resume, with no finger on the pad, and never releases
it (seen in both raw captures made; see EARLIER EPISODES for the
others). The desktop then treats the pointer as dragging: text selects
as soon as the pointer moves, and clicks are ignored until logout.

ENVIRONMENT

  Machine:   LENOVO 20Y10011US, ThinkPad P14s Gen 1 (AMD)
  BIOS:      R1BET87W (1.56), 06/04/2026
  OS/kernel: Ubuntu 26.04, 7.0.0-42-generic (linux-image 7.0.0-42.42)
  Session:   GNOME Shell 50.1 on Wayland, libinput 1.31.1
  Sleep:     mem_sleep = s2idle [deep]; suspends are S3 ("deep")
  Touchpad:  "SynPS/2 Synaptics TouchPad", Phys isa0060/serio1/input0,
             PNP LEN2064 PNP0f13, fw 10.32, id 0x1e2a1, board id 3471,
             /dev/input/event6; INPUT_PROP_BUTTONPAD
  Driver:    psmouse (PS/2). TrackPoint is "TPPS/2 Elan TrackPoint"
             (event7), on the Synaptics pass-through port.

STEPS TO REPRODUCE (no applications needed)

  1. Log in. Record the raw touchpad stream:
       sudo cat /dev/input/event6 > raw.bin
  2. systemctl suspend. Resume. Touch nothing for 10 seconds.
  3. Move the pointer (TrackPoint is enough). A text selection or
     drag starts.

OBSERVED (raw kernel events, EV_KEY only; traces attached)

  Run 2 (trace2-raw-evkey.txt), suspend entry 14:33:53, resume 14:34:04:
    14:33:53.719  BTN_LEFT  0     at suspend entry
    (no events at all for 11.8 s)
    14:34:05.509  BTN_LEFT  1     ~1.5 s after resume, no touch
    (no events for 24.7 s; no BTN_LEFT release for the rest of the file)

  Run 1 (trace1-raw-evkey.txt), suspend entry 14:23:53, resume 14:23:59:
    14:23:53.368  BTN_LEFT  0
    14:24:00.473  BTN_LEFT  1     ~1 s after resume, no touch, no release

  libinput (1.31.1) passes the press through faithfully:
  "event6 POINTER_BUTTON BTN_LEFT pressed, seat count: 1", never
  released (libinput-buttons-excerpt.txt). The TrackPoint's buttons
  (event7) still press and release normally while the touchpad's is
  stuck.

  The first BTN_LEFT event in each capture is a release with no press
  earlier in the capture. The kernel input core only emits a 0 when it
  believes the bit was 1, so I do not know how the bit became 1, or
  whether this release is related.

EARLIER EPISODES (libinput-level capture only, no raw stream)

  13:56 resume: press ~1.4 s after the wake key, never released.
  14:10 and 14:11 resumes (a different pattern): the press came ~27 s
  and ~20 s after the resume, with typing in between. The first was
  released ~1 s after the next suspend entry, as in the raw runs; the
  second was never released. I cannot say whether those were phantom
  presses or the pad being touched. An earlier episode on Oct 19
  (previous boot) had the same symptoms; nothing was captured and the
  cause is not confirmed.

WHAT I TRIED

  - Reloading psmouse (modprobe -r / modprobe): the press still occurs
    on the next resume (the 13:56 episode followed a reload at 13:39).
  - psmouse.synaptics_intertouch=1, also with rmi_smbus preloaded:
    the driver logs "Trying to set up SMBus access" then "SMbus
    companion is not ready yet" and falls back to PS/2, so the RMI
    path is not available here (intertouch-attempt.txt). The boot-time
    hint in dmesg is the same message the driver prints about LEN2064.
  - Touchpad disabled in GNOME (send-events disabled): one suspend/
    resume cycle, no wedge. This is the only workaround found; it
    costs the touchpad.

NOT KNOWN

  - Whether other kernel versions are affected, or whether a BIOS/EC
    update changes it. I have not tried an older kernel.
  - Whether the press originates in the touchpad firmware or in the
    driver's resume path (the log shows the driver re-querying the pad
    at resume, ~1 s before the press).
  - Whether a fresh boot, rather than a login/logout, changes the
    first-resume behaviour. All runs above are on one boot (11:53).

ATTACHMENTS

  trace1-raw-evkey.txt, trace2-raw-evkey.txt   decoded EV_KEY events
  trace1-kernel-journal.txt, trace2-kernel-journal.txt   PM/psmouse lines
  libinput-buttons-excerpt.txt   libinput debug-events button lines
  intertouch-attempt.txt         the SMBus fallback messages

ProblemType: Bug
DistroRelease: Ubuntu 26.04
Package: linux-image-7.0.0-42-generic 7.0.0-42.42
ProcVersionSignature: Ubuntu 7.0.0-42.42-generic 7.0.14
Uname: Linux 7.0.0-42-generic x86_64
ApportVersion: 2.34.1-0ubuntu0.1
Architecture: amd64
AudioDevicesInUse:
 USER        PID ACCESS COMMAND
 /dev/snd/controlC2:  user   259203 F.... wireplumber
 /dev/snd/controlC1:  user   259203 F.... wireplumber
 /dev/snd/controlC0:  user   259203 F.... wireplumber
 /dev/snd/seq:        user   259192 F.... pipewire
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Thu Oct 29 15:20:37 2026
InstallationDate: Installed on 2026-08-02 (88 days ago)
InstallationMedia: Ubuntu 26.04 "Resolute Raccoon" - Release amd64 (20260423.1)
MachineType: LENOVO 20Y10011US
ProcEnviron:
 LANG=en_US.UTF-8
 PATH=(custom, no user)
 SHELL=/bin/bash
 TERM=xterm-256color
 XDG_RUNTIME_DIR=<set>
ProcFB: 0 amdgpudrmfb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-7.0.0-42-generic 
root=/dev/mapper/ubuntu--vg-ubuntu--lv ro quiet splash 
crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M
PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No 
PulseAudio daemon running, or not running as session daemon.
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
WifiSyslog: (removed)
dmi.bios.date: 06/04/2026
dmi.bios.release: 1.56
dmi.bios.vendor: LENOVO
dmi.bios.version: R1BET87W(1.56 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20Y10011US
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40697 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.ec.firmware.release: 1.56
dmi.modalias: 
dmi:bvnLENOVO:bvrR1BET87W(1.56):bd06/04/2026:br1.56:efr1.56:svnLENOVO:pn20Y10011US:pvrThinkPadP14sGen1:rvnLENOVO:rn20Y10011US:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:skuLENOVO_MT_20Y1_BU_Think_FM_ThinkPadP14sGen1:pfaThinkPadP14sGen1:
dmi.product.family: ThinkPad P14s Gen 1
dmi.product.name: 20Y10011US
dmi.product.sku: LENOVO_MT_20Y1_BU_Think_FM_ThinkPad P14s Gen 1
dmi.product.version: ThinkPad P14s Gen 1
dmi.sys.vendor: LENOVO

** Affects: linux (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: amd64 apport-bug resolute wayland-session

** Attachment added: "raw touchpad traces, kernel journal excerpts, libinput 
excerpt, SMBus attempt"
   
https://bugs.launchpad.net/bugs/2172546/+attachment/6013503/+files/attachments-combined.txt

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https://bugs.launchpad.net/bugs/2172546

Title:
  phantom BTN_LEFT press after S3 resume (ThinkPad P14s Gen 1 AMD,
  LEN2064)

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