GPIO driven matrix keypad support

modulename: matrix_keypad.ko

configname: CONFIG_KEYBOARD_MATRIX

Linux Kernel Configuration
└─>Device Drivers
└─>Input device support
└─>Keyboards
└─>GPIO driven matrix keypad support
In linux kernel since version 2.6.31 (release Date: 2009-09-09)  
Enable support for GPIO driven matrix keypad.

To compile this driver as a module, choose M here: the
module will be called matrix_keypad.

source code: