tty: Move packet mode flow control notifications to pty driver

[firefly-linux-kernel-4.4.55.git] / drivers / tty / tty_io.c

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index b8ddfef6b5d8d0cb4e2a21e1632cfece69e6d2a5..c249ff1d51ceab8de81f0160a202317fea836167 100644 (file)
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -908,8 +908,7 @@ void no_tty(void)
  *     stop_tty        -       propagate flow control
  *     @tty: tty to stop
  *
- *     Perform flow control to the driver. For PTY/TTY pairs we
- *     must also propagate the TIOCKPKT status. May be called
+ *     Perform flow control to the driver. May be called
  *     on an already stopped device and will not re-call the driver
  *     method.
  *
@@ -919,24 +918,14 @@ void no_tty(void)
  *     but not always.
  *
  *     Locking:
- *             ctrl_lock
  *             flow_lock
  */
 
 void __stop_tty(struct tty_struct *tty)
 {
-       unsigned long flags;
-
        if (tty->stopped)
                return;
        tty->stopped = 1;
-       spin_lock_irqsave(&tty->ctrl_lock, flags);
-       if (tty->link && tty->link->packet) {
-               tty->ctrl_status &= ~TIOCPKT_START;
-               tty->ctrl_status |= TIOCPKT_STOP;
-               wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
-       }
-       spin_unlock_irqrestore(&tty->ctrl_lock, flags);
        if (tty->ops->stop)
                (tty->ops->stop)(tty);
 }
@@ -955,33 +944,21 @@ EXPORT_SYMBOL(stop_tty);
  *     start_tty       -       propagate flow control
  *     @tty: tty to start
  *
- *     Start a tty that has been stopped if at all possible. Perform
- *     any necessary wakeups and propagate the TIOCPKT status. If this
- *     is the tty was previous stopped and is being started then the
- *     driver start method is invoked and the line discipline woken.
+ *     Start a tty that has been stopped if at all possible. If this
+ *     tty was previous stopped and is now being started, the driver
+ *     start method is invoked and the line discipline woken.
  *
  *     Locking:
- *             ctrl_lock
  *             flow_lock
  */
 
 void __start_tty(struct tty_struct *tty)
 {
-       unsigned long flags;
-
        if (!tty->stopped || tty->flow_stopped)
                return;
        tty->stopped = 0;
-       spin_lock_irqsave(&tty->ctrl_lock, flags);
-       if (tty->link && tty->link->packet) {
-               tty->ctrl_status &= ~TIOCPKT_STOP;
-               tty->ctrl_status |= TIOCPKT_START;
-               wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
-       }
-       spin_unlock_irqrestore(&tty->ctrl_lock, flags);
        if (tty->ops->start)
                (tty->ops->start)(tty);
-       /* If we have a running line discipline it may need kicking */
        tty_wakeup(tty);
 }