Rotary encoders connected to GPIO pins

modulename: rotary_encoder.ko

configname: CONFIG_INPUT_GPIO_ROTARY_ENCODER

Linux Kernel Configuration
└─>Device Drivers
└─>Input device support
└─>Miscellaneous devices
└─>Rotary encoders connected to GPIO pins
In linux kernel since version 2.6.30 (release Date: 2009-06-09)  
Say Y here to add support for rotary encoders connected to GPIO lines.
Check file:Documentation/input/devices/rotary-encoder.rst for more
information.

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

source code:
depends
CONFIG_INPUT
CONFIG_INPUT_MISC
CONFIG_COMPILE_TEST or CONFIG_GPIOLIB