return 0;
 }
 
+static void hci_init0_req(struct hci_request *req, unsigned long opt)
+{
+       struct hci_dev *hdev = req->hdev;
+
+       BT_DBG("%s %ld", hdev->name, opt);
+
+       /* Reset */
+       if (!test_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks))
+               hci_reset_req(req, 0);
+
+       /* Read Local Version */
+       hci_req_add(req, HCI_OP_READ_LOCAL_VERSION, 0, NULL);
+
+       /* Read BD Address */
+       if (hdev->set_bdaddr)
+               hci_req_add(req, HCI_OP_READ_BD_ADDR, 0, NULL);
+}
+
+static int __hci_unconf_init(struct hci_dev *hdev)
+{
+       int err;
+
+       err = __hci_req_sync(hdev, hci_init0_req, 0, HCI_INIT_TIMEOUT);
+       if (err < 0)
+               return err;
+
+       return 0;
+}
+
 static void hci_scan_req(struct hci_request *req, unsigned long opt)
 {
        __u8 scan = opt;
                if (test_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks) ||
                    test_bit(HCI_QUIRK_INVALID_BDADDR, &hdev->quirks))
                        set_bit(HCI_UNCONFIGURED, &hdev->dev_flags);
+
+               /* For an unconfigured controller it is required to
+                * read at least the version information provided by
+                * the Read Local Version Information command.
+                *
+                * If the set_bdaddr driver callback is provided, then
+                * also the original Bluetooth public device address
+                * will be read using the Read BD Address command.
+                */
+               if (test_bit(HCI_UNCONFIGURED, &hdev->dev_flags))
+                       ret = __hci_unconf_init(hdev);
        }
 
        /* If public address change is configured, ensure that the