Fix some typos and while at it also use "PS" as the name for the central
"HOME" button on Sony controllers, this is how Sony itself calls it.
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NAntonio Ospite <ospite@studenti.unina.it>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

It wasn't really clear from the gamepad-API description how ABS values are
mapped exactly. Clarify that negative is left/up and positive is
right/down. Unfortunately, this means I screwed up the Wii U ProController
ABI. Anyhow, this just means we continue to have 0 compatible gamepad
drivers in the kernel. User-space needs to fix them up, anyway, as all
other gamepads are also incompatible.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Until today all gamepad input drivers report their data differently. It is
nearly impossible to write applications for more than one device in a
generic way. Therefore, this patch introduces a uniform gamepad API which
will be used for all new drivers.

Instead of mapping buttons by their labels, we now map them by position.
This allows applications to work with any gamepad regardless of the labels
on the buttons. Furthermore, we standardize the ABS_* codes for analog
triggers and sticks.

For D-Pads the long overdue BTN_DPAD_* codes are introduced. They should
be fairly obvious how to use. To avoid confusion, the action buttons now
have BTN_EAST/SOUTH/WEST/NORTH aliases.
Reported-by: NTodd Showalter <todd@electronjump.com>
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Acked-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>