In the current driver debugging process when access to certain register values, most of us output the value to the log file to see; In embedded Linux application development, parent process detect sub-process's state using the way child process initiatively send message to the parent process. Through analysis the registration, install, management of the proc file system can optimize the above problems, and put forward using proc file system to debugging of the driver and monitoring sub-state which have a great significance to speed up the debug of driver and improve the stability of the application.