USB: mos7840: fix broken TIOCMIWAIT

Make sure waiting processes are woken on modem-status changes.

Currently processes are only woken on termios changes regardless of
whether the modem status has changed.

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

1 files changed, 3 insertions, 2 deletions

diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index 809fb329eca5..1b83b01dfb77 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -423,6 +423,9 @@ static void mos7840_handle_new_msr(struct moschip_port *port, __u8 new_msr)
                         icount->rng++;
                         smp_wmb();
                 }
+
+                mos7840_port->delta_msr_cond = 1;
+                wake_up_interruptible(&mos7840_port->delta_msr_wait);
         }
 }
 
@@ -2017,8 +2020,6 @@ static void mos7840_change_port_settings(struct tty_struct *tty,
                         mos7840_port->read_urb_busy = false;
                 }
         }
-        wake_up(&mos7840_port->delta_msr_wait);
-        mos7840_port->delta_msr_cond = 1;
         dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is End %x\n", __func__,
                 mos7840_port->shadowLCR);
 }