int usb_register (struct usb_driver * new_driver);
Registers a USB driver with the USB core. The list of unattached interfaces will be rescanned whenever a new driver is added, allowing the new driver to attach to any recognized devices. Returns a negative error code on failure and 0 on success.
if you want your driver to use the USB major number, you must call usb_register_dev to enable that functionality. This function no longer takes care of that.