1 files changed, 1 insertions, 1 deletions

diff --git a/Documentation/serial/tty.txt b/Documentation/serial/tty.txt
index 7c900507279f..540db41dfd5d 100644
--- a/Documentation/serial/tty.txt
+++ b/Documentation/serial/tty.txt
@@ -107,7 +107,7 @@ write_wakeup()	-	May be called at any point between open and close.
 
 dcd_change()    -       Report to the tty line the current DCD pin status
                         changes and the relative timestamp. The timestamp
-                        can be NULL.
+                        cannot be NULL.
 
 
 Driver Access