On this machine, when closing the lid, the i8042 will generate a touchpad
toggle key event, while opeing the lid, the i8042 also generate a touchpad
toggle key event.

If users close the lid under the gnome environment, the touchpad toggle
key event will be captured by the gnome-settings-daemon, so the touchpad
is disabled by the daemon, when users open the lid, the system will go to
the login window (gnome-screensaver), so the touchpad toggle key event
generated by opening lid doesn't pass to gnome-settings-daemon, so the
touchpad doesn't restore to the original status.

There is a workaound, logging into the gnome, manually enable the touchpad
through:
dconf-editor->/org/gnome/settings-daemon/peripherals/touchpad/touchpad-enabled.

If we really want to fix this problem, we need to modify gnome-screensaver to
pass the function key event to gnome-settings-daemon, there is already a bug
to track this problem, the bug is 191041.

Not all laptop have this problem, most laptops don't generate touchpad
toggle key event when closing and opening the lid, so those machines don't
have this problem. Some laptops generate the touchpad toogle key event
when closing and opening the lid, but the touchpad toogle key isn't
activated by the udev, those machines don't have this problem as well.

An easy way to identify whether the machine has this problem is:
booting to gnome environment, pressing ALT+CTRL+F1 to enter text console,
executing showkey, closing lid, waiting several seconds, opening the lid,
if following logs are produced, your machine will have this problem.

keycode 191 press
keycode 191 release
keycode 191 press
keycode 191 release

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https://bugs.launchpad.net/bugs/1089105

Title:
  [Lenovo V480c Notebook]: System fails to resume properly from suspend

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