Re: [PATCH v3] Input: keyboard - add device tree bindings for simple key matrixes

On Tue, Jan 3, 2012 at 8:44 AM, Dmitry Torokhov
[off-list ref] wrote:

On Tue, Jan 03, 2012 at 04:29:30PM +0000, Russell King - ARM Linux wrote:

quoted

On Tue, Jan 03, 2012 at 08:22:21AM -0800, Simon Glass wrote:

quoted

Can the Linux key codes fit in 8 bits?

That depends on your point of view.

If you hack on X, then the answer is yes and you ignore the squeels of
your users when certain key presses get misinterpreted.  (The Psion LX
platform, otherwise known as the Netbook Pro, suffered with this problem.)

If you are a kernel hacker, the answer is no, because key codes currently
go all the way to 0x300.

For bootloader environment 0-255 range is probably sufficient though,
the upper keys are somewhat recent additions to the maps...

To keep things in common it would be convenient to not cap the key
code at 8 bits for everybody though, since we're looking at reaching
agreement on a common solution between firmware and linux. And no
matter what the size of the word is there will be need for a
translation table.


-Olof