[Question] How to write one keyboard driver without changing hid-input?

[liyu <liyu@ccoss.com.cn>]

Hi, everyone.

    I have a MS Natural Ergonomic Keyboard 4000 that have USB port.

    Under Windows XP, it work fine, however, Some extend keys do not 
work under Linux.
I found hid-input that do not report PRESS event to input-subsystem when 
such extend key
is pressed . I got this reason later, It map such "Zoom" key to 
KEY_UNKNOWN, and ignore them.
Its keymap is hard-coded.

    I try to write one driver for this keyboard now. but I found if we 
do not change or copy
hid-input.c, then I must write a lot of code to support it. Which guru 
wrote driver like
this under hid_input support? Would you like give some tips?

    I think this driver is simple. It only need we emit some event when 
key related is pressed,
do not need input event handler.
   
    Thanks in advanced.

-liyu