On Nov 03 2024, Ulrich Müller wrote:
After upgrading from 6.6.52 to 6.6.58, tapping on the touchpad stopped working. The problem is still present in 6.6.59.
I see the following in dmesg output; the first line was not there previously:
[ 2.129282] hid-multitouch 0018:27C6:01E0.0001: The byte is not expected for fixing the report descriptor. It's possible that the touchpad firmware is not suitable for applying the fix. got: 9 [ 2.137479] input: GXTP5140:00 27C6:01E0 as /devices/platform/AMDI0010:00/i2c-0/i2c-GXTP5140:00/0018:27C6:01E0.0001/input/input10 [ 2.137680] input: GXTP5140:00 27C6:01E0 as /devices/platform/AMDI0010:00/i2c-0/i2c-GXTP5140:00/0018:27C6:01E0.0001/input/input11 [ 2.137921] hid-multitouch 0018:27C6:01E0.0001: input,hidraw0: I2C HID v1.00 Mouse [GXTP5140:00 27C6:01E0] on i2c-GXTP5140:00
Hardware is a Lenovo ThinkPad L15 Gen 4.
The problem goes away when reverting this commit: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/dr...
See also Gentoo bug report: https://bugs.gentoo.org/942797
He Lugang,
It's been 3 weeks since this regression was reported and we haven't heard back from you. It's clear that the patch mentioned here is too gready and needs tuning to only apply to the firmware which needs the fix.
Could you quickly submit a fix that checks that the device is indeed requiring the fix (and thus the class MT_CLS_WIN_8_FORCE_MULTI_INPUT_NSMU) and if not, keep the default class?
Cheers, Benjamin