Increments the reference count of the usb device structure
struct usb_device * usb_get_dev(struct usb_device * dev);
dev
the device being referenced
Each live reference to a device should be refcounted.
Drivers for USB interfaces should normally record such references in their probe methods, when they bind to an interface, and release them by calling usb_put_dev, in their disconnect methods.
A pointer to the device with the incremented reference counter.