usbd_req_get_hub_descriptor
err = usbd_req_get_hub_descriptor(udev, NULL, &hubdesc20, 1);
err = usbd_req_get_hub_descriptor(udev, NULL, &hubdesc20, 1);
err = usbd_req_get_hub_descriptor(udev, NULL, &hubdesc20, nports);
usb_error_t usbd_req_get_hub_descriptor(struct usb_device *udev,