usb_alloc_dev — usb device constructor (usbcore-internal)
| struct usb_device * usb_alloc_dev ( | struct usb_device * parent, | 
| struct usb_bus * bus, | |
| unsigned port1 ); | 
parenthub to which device is connected; null to allocate a root hub
busbus used to access the device
port1one-based index of port; ignored for root hubs