well I am not the man for the job. I don't anything about kernels your the expert where do I find these files. I know battery , camera , and display drivers but not the usb ones .
In this post: http://www.devsnest.com/showthread.php?tid=87; describes a procedure for finding the changes applied in a kernel and generate a patch that can be applied to other kernel code.
USB changes are located in: drivers/usb/gadget