diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index c267412..3df10d5 100644
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -84,7 +84,7 @@
 	unsigned char		mcr_mask;	/* mask of user bits */
 	unsigned char		mcr_force;	/* mask of forced bits */
 	unsigned char		cur_iotype;	/* Running I/O type */
-	unsigned char		rpm_tx_active;
+	unsigned int		rpm_tx_active;
 
 	/*
 	 * Some bits in registers are cleared on a read, so they must