diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index da32889..49f3997 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -149,15 +149,14 @@
 static int pty_chars_in_buffer(struct tty_struct *tty)
 {
 	struct tty_struct *to = tty->link;
-	ssize_t (*chars_in_buffer)(struct tty_struct *);
 	int count;
 
 	/* We should get the line discipline lock for "tty->link" */
-	if (!to || !(chars_in_buffer = to->ldisc.chars_in_buffer))
+	if (!to || !to->ldisc.chars_in_buffer)
 		return 0;
 
 	/* The ldisc must report 0 if no characters available to be read */
-	count = chars_in_buffer(to);
+	count = to->ldisc.chars_in_buffer(to);
 
 	if (tty->driver->subtype == PTY_TYPE_SLAVE) return count;