diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index aa80dc94ddc2fe6969049a62479548c22a7931b5..f4dc3e296dd52dfd0270a890edcea817a5153bcd 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -422,7 +422,7 @@ EXPORT_SYMBOL_GPL(tty_prepare_flip_string);
  *
  *	Returns the number of bytes not processed
  */
-int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p,
+int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p,
 			  char *f, int count)
 {
 	if (ld->ops->receive_buf2)
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 86c7853282b7efafc32ab8046e1834f3e76c5f41..21c0fabfed60114ffb8b73482da951b9d0008f73 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -657,7 +657,7 @@ extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
 extern void tty_ldisc_release(struct tty_struct *tty);
 extern void tty_ldisc_init(struct tty_struct *tty);
 extern void tty_ldisc_deinit(struct tty_struct *tty);
-extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p,
+extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p,
 				 char *f, int count);
 
 /* n_tty.c */