1 files changed, 7 insertions, 5 deletions

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index c02e4602d90a..02e7f2d32d52 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -76,6 +76,7 @@ struct ftdi_private {
         struct async_icount     icount;
         wait_queue_head_t delta_msr_wait; /* Used for TIOCMIWAIT */
         char prev_status;        /* Used for TIOCMIWAIT */
+        bool dev_gone;        /* Used to abort TIOCMIWAIT */
         char transmit_empty;    /* If transmitter is empty or not */
         struct usb_serial_port *port;
         __u16 interface;        /* FT2232C, FT2232H or FT4232H port interface
@@ -1681,6 +1682,7 @@ static int ftdi_sio_port_probe(struct usb_serial_port *port)
         init_waitqueue_head(&priv->delta_msr_wait);
 
         priv->flags = ASYNC_LOW_LATENCY;
+        priv->dev_gone = false;
 
         if (quirk && quirk->port_probe)
                 quirk->port_probe(priv);
@@ -1839,6 +1841,9 @@ static int ftdi_sio_port_remove(struct usb_serial_port *port)
 
         dbg("%s", __func__);
 
+        priv->dev_gone = true;
+        wake_up_interruptible_all(&priv->delta_msr_wait);
+
         remove_sysfs_attrs(port);
 
         kref_put(&priv->kref, ftdi_sio_priv_release);
@@ -2397,15 +2402,12 @@ static int ftdi_ioctl(struct tty_struct *tty,
          */
         case TIOCMIWAIT:
                 cprev = priv->icount;
-                while (1) {
+                while (!priv->dev_gone) {
                         interruptible_sleep_on(&priv->delta_msr_wait);
                         /* see if a signal did it */
                         if (signal_pending(current))
                                 return -ERESTARTSYS;
                         cnow = priv->icount;
-                        if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
-                            cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
-                                return -EIO; /* no change => error */
                         if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
                             ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
                             ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
@@ -2414,7 +2416,7 @@ static int ftdi_ioctl(struct tty_struct *tty,
                         }
                         cprev = cnow;
                 }
-                /* not reached */
+                return -EIO;
                 break;
         case TIOCSERGETLSR:
                 return get_lsr_info(port, (struct serial_struct __user *)arg);