Bug 106601
| Summary: | Synaptics touchpad jumps on slow movements | ||
|---|---|---|---|
| Product: | Drivers | Reporter: | Ingo Bürk (ingo+kernel) |
| Component: | Input Devices | Assignee: | drivers_input-devices |
| Status: | NEW --- | ||
| Severity: | normal | CC: | dmitry.torokhov, ingo+kernel |
| Priority: | P1 | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Kernel Version: | 4.1.10 | Subsystem: | |
| Regression: | No | Bisected commit-id: | |
| Attachments: |
evtest
dmesg after fresh reboot |
||
I can reproduce this issue both on another laptop with the same touchpad model as well as on a T450 which uses a different touchpad model, so this just about has to be a kernel bug. Can I see the part of dmesg where we identify the touchpad (firmware version, capabilities, etc)? Created attachment 195811 [details]
dmesg after fresh reboot
@Dmitry Torokhov
Here you go, also attaching the entire dmesg of a fresh reboot just in case:
[ 3.027553] psmouse serio1: synaptics: queried max coordinates: x [..5676], y [..4758]
[ 3.059861] psmouse serio1: synaptics: queried min coordinates: x [1266..], y [1096..]
[ 3.122376] psmouse serio1: synaptics: Touchpad model: 1, fw: 8.1, id: 0x1e2b1, caps: 0xf003a3/0x943300/0x12e800/0x10000, board id: 3072, fw id: 1795685
[ 3.122385] psmouse serio1: synaptics: serio: Synaptics pass-through port at isa0060/serio1/input0
[ 3.161520] input: SynPS/2 Synaptics TouchPad as /devices/platform/i8042/serio1/input/input7
[ 3.163906] mousedev: PS/2 mouse device common for all mice
Loading psmouse with proto bare, imps or exps seems to work without running into this issue as well as far as I can tell (just to further rule out HW problems), but it also makes the touchpad go really slow and most touchpad features (gestures, …) etc. of course won't work anymore. For what it's worth, I can still reproduce this on kernel 4.4.0-rc2. |
Created attachment 191121 [details] evtest The synaptics touchpad on my ThinkPad X1 Carbon (3rd gen) is occasionally jumpy when moving the pointer with one finger, but it only seems to happen when moving really slow (like when adjusting a volume slider). I'll attach an evtest log and looking at it, it seems that when the jump happens, only pressure events are reported for a while and no motion events (see line 1658ff.). Given that I have this issue both with the userspace driver from synaptics and libinput, plus that I see the pressure event stuff in evtest, I assume this is either a kernel bug. A hardware problem is of course always possible as well, so if there's anything I can do to narrow it down, I'm glad to provide it. All I can say is that loading psmouse with proto=imps causes the issue to disappear (at the expense of pressure events and any multitouch functionality), but that wouldn't make the hardware provide different events, so my assumption is a kernel driver problem.