Bluetooth: Handle Intel USB bootloader with buggy interrupt

commit 3a5ef20c upstream.

The interrupt interface for the Intel USB bootloader devices is only
enabled after receiving SetInterface(0, AltSetting=0). When this USB
command is not send, then no HCI events will be received.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

drivers/bluetooth/btusb.c

@@ -1699,6 +1699,18 @@ static int btusb_probe(struct usb_interface *intf,
 		data->isoc = NULL;
 	}
 
+	if (id->driver_info & BTUSB_INTEL_BOOT) {
+		/* A bug in the bootloader causes that interrupt interface is
+		 * only enabled after receiving SetInterface(0, AltSetting=0).
+		 */
+		err = usb_set_interface(data->udev, 0, 0);
+		if (err < 0) {
+			BT_ERR("failed to set interface 0, alt 0 %d", err);
+			hci_free_dev(hdev);
+			return err;
+		}
+	}
+
 	if (data->isoc) {
 		err = usb_driver_claim_interface(&btusb_driver,
 							data->isoc, data);