This is the Hackerspace Warsaw electronic lock mk2 project.

Work in progress! This is a prototype for a TP-Link WR703n based hardware
solution - with a I2C bus on which there is a MAX7300 IO expander and a PN532
NFC tag reader. The I2C is software bit-banged by the kernel, drivers for both
the IO expander and the PN532 are written in Lua.

Files:
    hslockmk2/                       - this directory
             /main.lua               - main Lua script
             /i2c.lua                - I2C functions
             /nfc.lua                - NFC/PN532 functions
             /auth.lua               - auth API functions

             /lua-libs/              - other Lua libraries
                      /mips-bin/     - C libraries compiled for MIPS/OpenWRT
                      luai2c.tar.gz  - C i2c library
                      luasha2.tar.gz - C sha2 library
                      JSON.lua       - JSON library
                      bit.lua        - bitwise operations for Lua 5.1

You will additonally need luasec, luaposix and luasocket. But you can easily
find these in your favourite distribution, or even the OpenWRT source tree.