Here is a list of all files with brief descriptions:

[detail level 1234]

drivers
prom
at24cm0x
at24cm0x.c	Implementation of the AT24CM0X driver functions
at24cm0x.h	Header file with declarations and macros for driving an at24cm0x
hal
avr0
twi
twi.c	Source file with implementation of hardware TWI/I2C functions and macros
twi.h	Header file with declarations and macros for hardware TWI/I2C
common
defines
TWI_defines.h	Macro definitions for TWI/I2C communication flags and operations
enums
TWI_enums.h	Enumerations for TWI/I2C interface modes, operations, acknowledgment, and error codes
utils
macros
stringify.h	Helper macros for stringification in C preprocessor
systick
systick.c	Implements the SysTick utility functions
systick.h	Header file with declarations and macros for systick utility