Polled GPIO buttons

modulename: gpio_keys_polled.ko

configname: CONFIG_KEYBOARD_GPIO_POLLED

Linux Kernel Configuration
└─>Device Drivers
└─>Input device support
└─>Keyboards
└─>Polled GPIO buttons
In linux kernel since version 2.6.37 (release Date: 2011-01-04)  
This driver implements support for buttons connected
to GPIO pins that are not capable of generating interrupts.

Say Y here if your device has buttons connected
directly to such GPIO pins. Your board-specific
setup logic must also provide a platform device,
with configuration data saying which GPIOs are used.

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

source code: