Comment 11 for bug 1532746

I saved a dump of some seconds of the raw keyboard events doing:

cat /dev/input/event3 > /tmp/dump.bin

the result file can be downloaded from http://92.222.39.93/paolo/dump.bin (1.7 kb)
According to the kernel page at https://www.kernel.org/doc/Documentation/input/input.txt (see Event Interface chapter) I created a small C program to analyze the dump structure (can be found here: http://pastebin.com/RkMv0qJr).

An excerpt of the dump is this:

Time: 1456787793.748976 Type: 4 - Code: 4 - Value: 29
Time: 1456787793.748976 Type: 0 - Code: 0 - Value: 0
Time: 1456787793.750908 Type: 4 - Code: 4 - Value: 56
Time: 1456787793.750908 Type: 0 - Code: 0 - Value: 0
Time: 1456787793.754067 Type: 4 - Code: 4 - Value: 157
Time: 1456787793.754067 Type: 0 - Code: 0 - Value: 0
Time: 1456787793.756200 Type: 4 - Code: 4 - Value: 54
Time: 1456787793.756200 Type: 0 - Code: 0 - Value: 0
Time: 1456787793.759107 Type: 4 - Code: 4 - Value: 184
Time: 1456787793.759107 Type: 0 - Code: 0 - Value: 0
Time: 1456787795.307134 Type: 4 - Code: 4 - Value: 29
Time: 1456787795.307134 Type: 0 - Code: 0 - Value: 0
Time: 1456787795.308748 Type: 4 - Code: 4 - Value: 56
Time: 1456787795.308748 Type: 0 - Code: 0 - Value: 0
Time: 1456787795.311980 Type: 4 - Code: 4 - Value: 157
Time: 1456787795.311980 Type: 0 - Code: 0 - Value: 0
Time: 1456787795.313908 Type: 4 - Code: 4 - Value: 54
Time: 1456787795.313908 Type: 0 - Code: 0 - Value: 0
Time: 1456787795.317267 Type: 4 - Code: 4 - Value: 184
Time: 1456787795.317267 Type: 0 - Code: 0 - Value: 0

As I said, the computer was idling in the meantime the dump was taken.
As you see, every 1-2 seconds there is a pattern that repeats itself (the sequence repeats always in the same order).
In particular, Type 4 events are EV_MSC (see kernel docs at https://www.kernel.org/doc/Documentation/input/event-codes.txt) meaning "Miscellaneous events", and Code 4 subtype means MSC_SCAN (according to /usr/include/linux/input.h kernel file), which someway is used to "redefine" or map keyboard keys.
Values in the dump also are interesting, because apparently they are keystroke numbers and still according to /usr/include/linux/input.h they are:

29 -> KEY_LEFTCTRL
56 -> KEY_LEFTALT
157 -> KEY_COMPUTER
54 -> KEY_RIGHTSHIFT
184 -> KEY_F14

Curiously they are followed by a reserved event (type: 0), which is of unknown usage to me.