tty: fix tty_port_block_til_ready waiting

[pandora-kernel.git] / drivers / char / tty_port.c

diff --git a/drivers/char/tty_port.c b/drivers/char/tty_port.c
index 9b8004c..4e862a7 100644 (file)
--- a/drivers/char/tty_port.c
+++ b/drivers/char/tty_port.c
@@ -137,7 +137,7 @@ int tty_port_carrier_raised(struct tty_port *port)
 EXPORT_SYMBOL(tty_port_carrier_raised);
 
 /**
- *     tty_port_raise_dtr_rts  -       Riase DTR/RTS
+ *     tty_port_raise_dtr_rts  -       Raise DTR/RTS
  *     @port: tty port
  *
  *     Wrapper for the DTR/RTS raise logic. For the moment this is used
@@ -147,11 +147,27 @@ EXPORT_SYMBOL(tty_port_carrier_raised);
 
 void tty_port_raise_dtr_rts(struct tty_port *port)
 {
-       if (port->ops->raise_dtr_rts)
-               port->ops->raise_dtr_rts(port);
+       if (port->ops->dtr_rts)
+               port->ops->dtr_rts(port, 1);
 }
 EXPORT_SYMBOL(tty_port_raise_dtr_rts);
 
+/**
+ *     tty_port_lower_dtr_rts  -       Lower DTR/RTS
+ *     @port: tty port
+ *
+ *     Wrapper for the DTR/RTS raise logic. For the moment this is used
+ *     to hide some internal details. This will eventually become entirely
+ *     internal to the tty port.
+ */
+
+void tty_port_lower_dtr_rts(struct tty_port *port)
+{
+       if (port->ops->dtr_rts)
+               port->ops->dtr_rts(port, 0);
+}
+EXPORT_SYMBOL(tty_port_lower_dtr_rts);
+
 /**
  *     tty_port_block_til_ready        -       Waiting logic for tty open
  *     @port: the tty port being opened
@@ -167,7 +183,7 @@ EXPORT_SYMBOL(tty_port_raise_dtr_rts);
  *             - port flags and counts
  *
  *     The passed tty_port must implement the carrier_raised method if it can
- *     do carrier detect and the raise_dtr_rts method if it supports software
+ *     do carrier detect and the dtr_rts method if it supports software
  *     management of these lines. Note that the dtr/rts raise is done each
  *     iteration as a hangup may have previously dropped them while we wait.
  */
@@ -177,12 +193,13 @@ int tty_port_block_til_ready(struct tty_port *port,
 {
        int do_clocal = 0, retval;
        unsigned long flags;
-       DECLARE_WAITQUEUE(wait, current);
+       DEFINE_WAIT(wait);
        int cd;
 
        /* block if port is in the process of being closed */
        if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) {
-               interruptible_sleep_on(&port->close_wait);
+               wait_event_interruptible(port->close_wait,
+                               !(port->flags & ASYNC_CLOSING));
                if (port->flags & ASYNC_HUP_NOTIFY)
                        return -EAGAIN;
                else
@@ -205,7 +222,6 @@ int tty_port_block_til_ready(struct tty_port *port,
           before the next open may complete */
 
        retval = 0;
-       add_wait_queue(&port->open_wait, &wait);
 
        /* The port lock protects the port counts */
        spin_lock_irqsave(&port->lock, flags);
@@ -219,7 +235,7 @@ int tty_port_block_til_ready(struct tty_port *port,
                if (tty->termios->c_cflag & CBAUD)
                        tty_port_raise_dtr_rts(port);
 
-               set_current_state(TASK_INTERRUPTIBLE);
+               prepare_to_wait(&port->open_wait, &wait, TASK_INTERRUPTIBLE);
                /* Check for a hangup or uninitialised port. Return accordingly */
                if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)) {
                        if (port->flags & ASYNC_HUP_NOTIFY)
@@ -240,8 +256,7 @@ int tty_port_block_til_ready(struct tty_port *port,
                }
                schedule();
        }
-       set_current_state(TASK_RUNNING);
-       remove_wait_queue(&port->open_wait, &wait);
+       finish_wait(&port->open_wait, &wait);
 
        /* Update counts. A parallel hangup will have set count to zero and
           we must not mess that up further */
@@ -292,6 +307,17 @@ int tty_port_close_start(struct tty_port *port, struct tty_struct *tty, struct f
        if (port->flags & ASYNC_INITIALIZED &&
                        port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
                tty_wait_until_sent(tty, port->closing_wait);
+       if (port->drain_delay) {
+               unsigned int bps = tty_get_baud_rate(tty);
+               long timeout;
+
+               if (bps > 1200)
+                       timeout = max_t(long, (HZ * 10 * port->drain_delay) / bps,
+                                                               HZ / 10);
+               else
+                       timeout = 2 * HZ;
+               schedule_timeout_interruptible(timeout);
+       }
        return 1;
 }
 EXPORT_SYMBOL(tty_port_close_start);
@@ -302,6 +328,9 @@ void tty_port_close_end(struct tty_port *port, struct tty_struct *tty)
 
        tty_ldisc_flush(tty);
 
+       if (tty->termios->c_cflag & HUPCL)
+               tty_port_lower_dtr_rts(port);
+
        spin_lock_irqsave(&port->lock, flags);
        tty->closing = 0;