tty: Introduce a tty_port generic block_til_ready

Start sucking more commonality out of the drivers into a single piece of
core code.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 70 deletions

diff --git a/drivers/char/mxser.c b/drivers/char/mxser.c
index e2471cf1ee95..08ba6eb1a380 100644
--- a/drivers/char/mxser.c
+++ b/drivers/char/mxser.c
@@ -558,75 +558,6 @@ static void mxser_raise_dtr_rts(struct tty_port *port)
         spin_unlock_irqrestore(&mp->slock, flags);
 }
 
-static int mxser_block_til_ready(struct tty_struct *tty, struct file *filp,
-                struct mxser_port *mp)
-{
-        DECLARE_WAITQUEUE(wait, current);
-        int retval;
-        int do_clocal = 0;
-        unsigned long flags;
-        int cd;
-        struct tty_port *port = &mp->port;
-
-        /*
-         * If non-blocking mode is set, or the port is not enabled,
-         * then make the check up front and then exit.
-         */
-        if ((filp->f_flags & O_NONBLOCK) ||
-                        test_bit(TTY_IO_ERROR, &tty->flags)) {
-                port->flags |= ASYNC_NORMAL_ACTIVE;
-                return 0;
-        }
-
-        if (tty->termios->c_cflag & CLOCAL)
-                do_clocal = 1;
-
-        /*
-         * Block waiting for the carrier detect and the line to become
-         * free (i.e., not in use by the callout).  While we are in
-         * this loop, port->count is dropped by one, so that
-         * mxser_close() knows when to free things.  We restore it upon
-         * exit, either normal or abnormal.
-         */
-        retval = 0;
-        add_wait_queue(&port->open_wait, &wait);
-
-        spin_lock_irqsave(&port->lock, flags);
-        if (!tty_hung_up_p(filp))
-                port->count--;
-        port->blocked_open++;
-        spin_unlock_irqrestore(&port->lock, flags);
-        while (1) {
-                tty_port_raise_dtr_rts(port);
-                set_current_state(TASK_INTERRUPTIBLE);
-                if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)) {
-                        if (port->flags & ASYNC_HUP_NOTIFY)
-                                retval = -EAGAIN;
-                        else
-                                retval = -ERESTARTSYS;
-                        break;
-                }
-                cd = tty_port_carrier_raised(port);
-                if (!(port->flags & ASYNC_CLOSING) && (do_clocal || cd))
-                        break;
-                if (signal_pending(current)) {
-                        retval = -ERESTARTSYS;
-                        break;
-                }
-                schedule();
-        }
-        set_current_state(TASK_RUNNING);
-        remove_wait_queue(&port->open_wait, &wait);
-        spin_lock_irqsave(&port->lock, flags);
-        if (!tty_hung_up_p(filp))
-                port->count++;
-        port->blocked_open--;
-        if (retval == 0)
-                port->flags |= ASYNC_NORMAL_ACTIVE;
-        spin_unlock_irqrestore(&port->lock, flags);
-        return 0;
-}
-
 static int mxser_set_baud(struct tty_struct *tty, long newspd)
 {
         struct mxser_port *info = tty->driver_data;
@@ -1110,7 +1041,7 @@ static int mxser_open(struct tty_struct *tty, struct file *filp)
         if (retval)
                 return retval;
 
-        retval = mxser_block_til_ready(tty, filp, info);
+        retval = tty_port_block_til_ready(&info->port, tty, filp);
         if (retval)
                 return retval;