Can a kernel module call the function of another kernel module
 

I could not find any reference about a kernel module calling the function of another kernel module.

Can this be done?

Yes. Of course, the other kernel module must be loaded.

For an example, look at the USB code, which is implemented as a mullti-layer driver, with each layer in its own module.

Thanks rjlee
 

Pardon me as I'm quite a beginner at kernel programming.

I am reading the usb kernel module you have mentioned and it's quite complicated.

Can you give an example, maybe using the popular helloworld program.

Look into this
==================
http://tldp.org/LDP/lkmpg/2.4/html/x437.html