USB: pl2303: fix TIOCMIWAIT and disconnect

Use tty-port modem-status-change wait queue on which processes are woken
up at hangup and disconnect.

Currently a process waiting on modem-status changes will not be woken on
device disconnect.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/pl2303.c

@@ -607,7 +607,7 @@ static int pl2303_tiocmiwait(struct tty_struct *tty, unsigned long arg)
 	spin_unlock_irqrestore(&priv->lock, flags);
 
 	while (1) {
-		interruptible_sleep_on(&port->delta_msr_wait);
+		interruptible_sleep_on(&port->port.delta_msr_wait);
 		/* see if a signal did it */
 		if (signal_pending(current))
 			return -ERESTARTSYS;
@@ -718,7 +718,7 @@ static void pl2303_update_line_status(struct usb_serial_port *port,
 	spin_unlock_irqrestore(&priv->lock, flags);
 	if (priv->line_status & UART_BREAK_ERROR)
 		usb_serial_handle_break(port);
-	wake_up_interruptible(&port->delta_msr_wait);
+	wake_up_interruptible(&port->port.delta_msr_wait);
 
 	tty = tty_port_tty_get(&port->port);
 	if (!tty)
@@ -782,7 +782,7 @@ static void pl2303_process_read_urb(struct urb *urb)
 	line_status = priv->line_status;
 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
 	spin_unlock_irqrestore(&priv->lock, flags);
-	wake_up_interruptible(&port->delta_msr_wait);
+	wake_up_interruptible(&port->port.delta_msr_wait);
 
 	if (!urb->actual_length)
 		return;