Char device driver

Character device driver is similar to the file in linux.
Character device driver is made to read and write a stream of char data to/from the Hardware device.

The char device contains 3 fundamental kernel data structures.

1. inode
2. file
3. file_operations

inode

inode data structure represents the file internally inside the kernel.

file

file data structure represents an opened file inside the kernel, it is somewhat similar to the file_descriptor that we use in userspace programs.

file_operations

file_operations data structure contains pointers to the methods(functions) which implement a particular file operation.

for example: open(), close(), read(), write().