USB: usb_wwan: do not resume I/O on closing ports

Use tty-port initialised flag rather than private flag to determine when
port is closing down.

Since the tty-port flag is set prior to dropping DTR/RTS (when HUPCL is
set) this avoid submitting the read urbs when resuming the interface in
dtr_rts() only to immediately kill them again in shutdown().

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/serial/usb_wwan.c b/drivers/usb/serial/usb_wwan.c
index bbcbdaa..2932d9c 100644
--- a/drivers/usb/serial/usb_wwan.c
+++ b/drivers/usb/serial/usb_wwan.c
@@ -395,7 +395,6 @@
 	}
 
 	spin_lock_irq(&intfdata->susp_lock);
-	portdata->opened = 1;
 	if (++intfdata->open_ports == 1)
 		serial->interface->needs_remote_wakeup = 1;
 	spin_unlock_irq(&intfdata->susp_lock);
@@ -429,8 +428,11 @@
 
 	portdata = usb_get_serial_port_data(port);
 
+	/*
+	 * Need to take susp_lock to make sure port is not already being
+	 * resumed, but no need to hold it due to ASYNC_INITIALIZED.
+	 */
 	spin_lock_irq(&intfdata->susp_lock);
-	portdata->opened = 0;
 	if (--intfdata->open_ports == 0)
 		serial->interface->needs_remote_wakeup = 0;
 	spin_unlock_irq(&intfdata->susp_lock);
@@ -645,11 +647,12 @@
 	spin_lock_irq(&intfdata->susp_lock);
 	for (i = 0; i < serial->num_ports; i++) {
 		port = serial->port[i];
-		portdata = usb_get_serial_port_data(port);
 
-		if (!portdata || !portdata->opened)
+		if (!test_bit(ASYNCB_INITIALIZED, &port->port.flags))
 			continue;
 
+		portdata = usb_get_serial_port_data(port);
+
 		if (port->interrupt_in_urb) {
 			err = usb_submit_urb(port->interrupt_in_urb,
 					GFP_ATOMIC);