From e33fe4d86f91127f6f7d931ff59ed6cbda06e72b Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Mon, 21 Jan 2008 17:44:10 +0100 Subject: USB: make sure usb serial drivers don't flush to logically disconnected devices If disconnect() is called for a logical disconnect, no more IO must be done after disconnect() returns, or the old and new drivers may conflict. This patch avoids this by using the flag and lock introduced by the earlier patch for the mos7720 driver. Signed-off-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/mct_u232.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) (limited to 'drivers/usb/serial/mct_u232.c') 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); } -- cgit v1.2.1