diff --git a/tools/net/ynl/ynl-gen-c.py b/tools/net/ynl/ynl-gen-c.py
index 8098bcbb6f404..7f6e5157770d3 100755
--- a/tools/net/ynl/ynl-gen-c.py
+++ b/tools/net/ynl/ynl-gen-c.py
@@ -2706,7 +2706,8 @@ def find_kernel_root(full_path):
 
 def main():
     parser = argparse.ArgumentParser(description='Netlink simple parsing generator')
-    parser.add_argument('--mode', dest='mode', type=str, required=True)
+    parser.add_argument('--mode', dest='mode', type=str, required=True,
+                        choices=('user', 'kernel', 'uapi'))
     parser.add_argument('--spec', dest='spec', type=str, required=True)
     parser.add_argument('--header', dest='header', action='store_true', default=None)
     parser.add_argument('--source', dest='header', action='store_false')