diff --git a/include/linux/serial.h b/include/linux/serial.h
index 0916107c77f9..0b8b7d7c8f33 100644
--- a/include/linux/serial.h
+++ b/include/linux/serial.h
@@ -12,6 +12,8 @@
 #include <asm/page.h>
 #include <uapi/linux/serial.h>
 
+/* Helper for dealing with UART_LCR_WLEN* defines */
+#define UART_LCR_WLEN(x)	((x) - 5)
 
 /*
  * Counters of the input lines (CTS, DSR, RI, CD) interrupts