n_hdlc: remove unused backup_tty

It's only set to NULL and never properly used.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index d0e538ba51ea66caf751bfe7035f632f184d8989..ae6b9a45ae8177a5c09bb7df8c1b78d4fcd679c6 100644 (file)
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -125,7 +125,6 @@ struct n_hdlc_buf_list {
  * struct n_hdlc - per device instance data structure
  * @magic - magic value for structure
  * @tty - ptr to TTY structure
- * @backup_tty - TTY to use if tty gets closed
  * @tbusy - reentrancy flag for tx wakeup code
  * @woke_up - FIXME: describe this field
  * @tx_buf_list - list of pending transmit frame buffers
@@ -136,7 +135,6 @@ struct n_hdlc_buf_list {
 struct n_hdlc {
        int                     magic;
        struct tty_struct       *tty;
-       struct tty_struct       *backup_tty;
        int                     tbusy;
        int                     woke_up;
        struct n_hdlc_buf_list  tx_buf_list;
@@ -267,15 +265,9 @@ static void n_hdlc_tty_close(struct tty_struct *tty)
        clear_bit(TTY_NO_WRITE_SPLIT,&tty->flags);
 #endif
        tty->disc_data = NULL;
-       if (tty == n_hdlc->backup_tty)
-               n_hdlc->backup_tty = NULL;
        if (tty != n_hdlc->tty)
                return;
-       if (n_hdlc->backup_tty) {
-               n_hdlc->tty = n_hdlc->backup_tty;
-       } else {
-               n_hdlc_release (n_hdlc);
-       }
+       n_hdlc_release (n_hdlc);
 }      /* end of n_hdlc_tty_close() */
 
 /**