Artem Pak 
Hello, I need to develop a module that will control several GPIO ports. The ports will be used mostly as I/O and it is necessary to control input. I'm new in driver development and without experience it is very hard for me to dig Internet for appropriate resources and some of them don't provide complete information on how to do the things. My question is more related to the approach to use here. As I understand, I need to develop kernel module that will do the actual job. However I have no idea what is the proper way to communicate with main application :-( To perform port writing I saw some samples using 'ioctl', but when I need to control the port state.... should I do cyclic reading??? I'm sure there is a good solution for this, but I cannot find it by myself. Please give me advice on how to resolve this... I would be happy if you provide me with some resource that explains common approach that might be used here. Many thanks for your attention.