I was able to build a "hello world" module with following properties:

file_module.c: Implements the following

• module_init
• Calls method to register char device
• module_exit
• Calls methods to deregister char device

file_chardev.c: Implements the following

• extern struct file_operations
• Method to register a char device
• Method to deregister a char device

file_fops_impl.h: Implements the following

• Declares prototypes of methods used to initialize members of struct file_operations

file_fops.c: Implements the following

• include header file: file_fops_impl.h
• struct file_operation fops = { - - - }

file_fops_impl.c: Implements the following

• include header file: file_fops_impl.h
• Methods that are used to initialize members of struct file_operations

My earlier question became moot when I tried again the same code after a reboot. What is strange is the call to module_init() didn't print any kernel log messages even though I had print statement with error mode.