After upgrading the kernel from 6.0 series to the 6.1 the touchpad on my asus t100 no longer works.
The device is registered in dmesg. I believe hid_asus is responsible for the keyboard and touchpad. The keyboard continues to function, but the touchpad does not.
Jan 29 09:29:53 t100ta-white kernel: asus 0003:0B05:17E0.0001: input,hidraw0: USB HID v1.11 Keyboard [ASUSTek COMPUTER INC. ASUS Base Station(T100)] on usb-0000:00:14.0-3/input0
Jan 29 09:29:53 t100ta-white kernel: asus 0003:0B05:17E0.0002: Fixing up Asus T100 keyb report descriptor
Jan 29 09:29:53 t100ta-white kernel: asus 0003:0B05:17E0.0002: input,hiddev96,hidraw1: USB HID v1.11 Device [ASUSTek COMPUTER INC. ASUS Base Station(T100)] on usb-0000:00:14.0-3/input1
Jan 29 09:29:53 t100ta-white kernel: asus 0003:0B05:17E0.0003: input,hiddev97,hidraw2: USB HID v1.11 Mouse [ASUSTek COMPUTER INC. ASUS Base Station(T100)] on usb-0000:00:14.0-3/input2
I do not see any changes to hid_asus that should be responsible for the change in performance.
This is my bad, I accidentally broke SW_TABLET_MODE reporting on the Asus T100* and T101* series and it is now reporting that it is in tablet mode while it is actually docked and thus in laptop mode.
This is causing libinput to suppress touchpad events, as it would for a 360° hinges style 2 in 1 with the keyboard + touchpad folded behind the display (so in tablet mode).
I recently hit this myself on a T101HA and a fix for this has already been merged for 6.2-rc6:
"platform/x86: asus-wmi: Fix kbd_dock_devid tablet-switch reporting"
And the fix is also queued for the next 6.1.y stable series release: