The GPIO bit-bang driver creates an interface to Linux GPIOs using the IOCTL API.

Basic 1-bit input and output is available along with accelerated multiple bit shift I/O.

GPIO bit-bang is well suited to PICMicro ICSP but not exclusively.

First install development tools and the kernel headers.

xbps-install mercurial make gcc rpi-kernel-headers 

Now install the kernel module.

hg clone http://hg.kewl.org/pub/gpio-bb
cd gpio-bb
./install.sh

Update modprobe configuration to create the gpio-bb device node when the module is loaded.

install gpio-bb modprobe --ignore-install gpio-bb && modprobe gpio-bb && mknod /dev/gpio-bb c 180 0

GPIO bit-bang driver for OpenWRT

GPIO bit-bang driver for Raspbian