diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 53f40c5..3953d17 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Thunderbolt Cactus Ridge driver - switch/port utility functions
  *