1 files changed, 8 insertions, 6 deletions

diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c
index 8efa19d0e9fb..ba7352e4187e 100644
--- a/drivers/usb/serial/cypress_m8.c
+++ b/drivers/usb/serial/cypress_m8.c
@@ -111,7 +111,6 @@ struct cypress_private {
         int baud_rate;                     /* stores current baud rate in
                                               integer form */
         int isthrottled;                   /* if throttled, discard reads */
-        wait_queue_head_t delta_msr_wait;  /* used for TIOCMIWAIT */
         char prev_status, diff_status;     /* used for TIOCMIWAIT */
         /* we pass a pointer to this as the argument sent to
            cypress_set_termios old_termios */
@@ -449,7 +448,6 @@ static int cypress_generic_port_probe(struct usb_serial_port *port)
                 kfree(priv);
                 return -ENOMEM;
         }
-        init_waitqueue_head(&priv->delta_msr_wait);
 
         usb_reset_configuration(serial->dev);
 
@@ -868,12 +866,16 @@ static int cypress_ioctl(struct tty_struct *tty,
         switch (cmd) {
         /* This code comes from drivers/char/serial.c and ftdi_sio.c */
         case TIOCMIWAIT:
-                while (priv != NULL) {
-                        interruptible_sleep_on(&priv->delta_msr_wait);
+                for (;;) {
+                        interruptible_sleep_on(&port->delta_msr_wait);
                         /* see if a signal did it */
                         if (signal_pending(current))
                                 return -ERESTARTSYS;
-                        else {
+
+                        if (port->serial->disconnected)
+                                return -EIO;
+
+                        {
                                 char diff = priv->diff_status;
                                 if (diff == 0)
                                         return -EIO; /* no change => error */
@@ -1187,7 +1189,7 @@ static void cypress_read_int_callback(struct urb *urb)
         if (priv->current_status != priv->prev_status) {
                 priv->diff_status |= priv->current_status ^
                         priv->prev_status;
-                wake_up_interruptible(&priv->delta_msr_wait);
+                wake_up_interruptible(&port->delta_msr_wait);
                 priv->prev_status = priv->current_status;
         }
         spin_unlock_irqrestore(&priv->lock, flags);