USB: pl2303: fix abuse of interface data

Fix abuse of interface data which was used to signal device disconnect.

Use the usb_serial disconnect flag and mutex where appropriate.

Note that tiocmget does not need to check for disconnect as it does not
access the device.

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

diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index a1a9062954c471f57f4b173490a7bcd2a62a210c..4917b4e79bb522f6222e312aae7ff5c5f06e6d80 100644 (file)
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -523,12 +523,11 @@ static int pl2303_tiocmset(struct tty_struct *tty,
                           unsigned int set, unsigned int clear)
 {
        struct usb_serial_port *port = tty->driver_data;
+       struct usb_serial *serial = port->serial;
        struct pl2303_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;
        u8 control;
-
-       if (!usb_get_intfdata(port->serial->interface))
-               return -ENODEV;
+       int ret;
 
        spin_lock_irqsave(&priv->lock, flags);
        if (set & TIOCM_RTS)
@@ -542,7 +541,14 @@ static int pl2303_tiocmset(struct tty_struct *tty,
        control = priv->line_control;
        spin_unlock_irqrestore(&priv->lock, flags);
 
-       return set_control_lines(port->serial->dev, control);
+       mutex_lock(&serial->disc_mutex);
+       if (!serial->disconnected)
+               ret = set_control_lines(serial->dev, control);
+       else
+               ret = -ENODEV;
+       mutex_unlock(&serial->disc_mutex);
+
+       return ret;
 }
 
 static int pl2303_tiocmget(struct tty_struct *tty)
@@ -556,9 +562,6 @@ static int pl2303_tiocmget(struct tty_struct *tty)
 
        dbg("%s (%d)", __func__, port->number);
 
-       if (!usb_get_intfdata(port->serial->interface))
-               return -ENODEV;
-
        spin_lock_irqsave(&priv->lock, flags);
        mcr = priv->line_control;
        status = priv->line_status;