* Stop trying to be smart and generate repeats on the fly; this breaks
time consistency. Also if repeats are not handled in time this causes
infinite loops.
* Move rarely-used functions to external files, simplify stuff, get rid
of internal driver events; saves ~1 kB per add-in overall.
The new keyboard device (keydev) interface implements the kernel's view
of a keyboard providing input events. Its main role is to abstract all
the globals of the KEYSC driver and getkey functions into a separate
object: the "keyboard device".
The device implements event transformations such as modifiers and
repeats, instead of leaving them to getkey. While this can seem
surprising at first, a real keyboard controller is responsible for
repeats and modifier actions depend on the state of the keyboard which
is only tracked in real-time.
In this commit, getkey() has not changed yet apart from indirectly using
the keydev interface with pollevent(). It will be changed soon to use
event transforms in keydev_read(), and will be left in charge of
providing repeat profiles, handling return-to-menu, backlight changes
and timeouts, all of which are user convenience features.