diff options
Diffstat (limited to 'drivers/usb/serial/mct_u232.c')
-rw-r--r-- | drivers/usb/serial/mct_u232.c | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/drivers/usb/serial/mct_u232.c b/drivers/usb/serial/mct_u232.c index 88b2074867c5..fc1cea4aba13 100644 --- a/drivers/usb/serial/mct_u232.c +++ b/drivers/usb/serial/mct_u232.c @@ -487,21 +487,22 @@ error: static void mct_u232_close (struct usb_serial_port *port, struct file *filp) { unsigned int c_cflag; - unsigned long flags; unsigned int control_state; struct mct_u232_private *priv = usb_get_serial_port_data(port); dbg("%s port %d", __FUNCTION__, port->number); if (port->tty) { c_cflag = port->tty->termios->c_cflag; - if (c_cflag & HUPCL) { - /* drop DTR and RTS */ - spin_lock_irqsave(&priv->lock, flags); - priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS); - control_state = priv->control_state; - spin_unlock_irqrestore(&priv->lock, flags); - mct_u232_set_modem_ctrl(port->serial, control_state); + mutex_lock(&port->serial->disc_mutex); + if (c_cflag & HUPCL && !port->serial->disconnected) { + /* drop DTR and RTS */ + spin_lock_irq(&priv->lock); + priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS); + control_state = priv->control_state; + spin_unlock_irq(&priv->lock); + mct_u232_set_modem_ctrl(port->serial, control_state); } + mutex_unlock(&port->serial->disc_mutex); } |