Comment 157 for bug 405120

I've done some research for duplicate bug #1009773.

The results are very predictable.
The bug is already fixed in Linux kernel packaged for Ubuntu Quantal (version 3.4.0 at that time).
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Why is it already fixed there?

The patch fixing this issue has been merged in Linux v3.3-rc1: http://bugzilla.kernel.org/show_bug.cgi?id=15612#c22
("Input: i8042 - also perform controller reset when suspending").
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The possible explanation of the bug and the fix is following.
A MCU firmware emulated i8042 controller is a rather buggy thing sometimes going into unstable state: https://bugzilla.kernel.org/show_bug.cgi?id=15612#c19

To make it work correctly because of going into wrong states, it needs to be reset.

In our Acer models, it seems to work correctly most of times without reset (it only seems to glitch on suspend); therefore, enabling "i8042.reset" kernel option is an excessive one.

A patch named "Automatically reset controller on S2R" (merged in Linux v3.3-rc1: "Input: i8042 - also perform controller reset when suspending") forces this (emulated) i8042 controller to be reset on suspend by default, regardless of the system type (before that, by default, i8042 was forcibly reset by only on resume).

Well, with Linux >= 3.3, suspend should began to work out of the box on a greater number of machines.