add GPL v2+ SPDX header

Signed-off-by: Felix Fietkau <nbd@nbd.name>

3 files changed, 3 insertions, 0 deletions

diff --git a/main.c b/main.c
index 6cfe3b2..2f59495 100644
--- a/main.c
+++ b/main.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 #include <stdio.h>
 #include <getopt.h>
 #include <stdbool.h>
diff --git a/switch.c b/switch.c
index 6285c7c..3716bb7 100644
--- a/switch.c
+++ b/switch.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 #include <unistd.h>
 #include "switch.h"
 
diff --git a/switch.h b/switch.h
index e499326..309543e 100644
--- a/switch.h
+++ b/switch.h
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 #ifndef __USBMODE_SWITCH_H
 #define __USBMODE_SWITCH_H