USB: serial: sierra driver send_setup() autopm fix

This patch presents a fix for the autosuspend feature implementation in
sierra usb serial driver for function sierra_send_setup().  Because it
is possible to call sierra_send_setup() before sierra_open() or after
sierra_close() we added a get/put interface activity to assure that the
usb control can happen even when the device is autosuspended.

Signed-off-by: Elina Pasheva <epasheva@sierrawireless.com>
Tested-by: Matthew Safar <msafar@sierrawireless.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 14 insertions, 10 deletions

diff --git a/drivers/usb/serial/sierra.c b/drivers/usb/serial/sierra.c
index 45883988a005..3ec79dfc41fd 100644
--- a/drivers/usb/serial/sierra.c
+++ b/drivers/usb/serial/sierra.c
@@ -296,7 +296,6 @@ struct sierra_port_private {
         int dsr_state;
         int dcd_state;
         int ri_state;
-
         unsigned int opened:1;
 };
 
@@ -306,6 +305,8 @@ static int sierra_send_setup(struct usb_serial_port *port)
         struct sierra_port_private *portdata;
         __u16 interface = 0;
         int val = 0;
+        int do_send = 0;
+        int retval;
 
         dev_dbg(&port->dev, "%s\n", __func__);
 
@@ -324,10 +325,7 @@ static int sierra_send_setup(struct usb_serial_port *port)
                  */
                 if (port->interrupt_in_urb) {
                         /* send control message */
-                        return usb_control_msg(serial->dev,
-                                usb_rcvctrlpipe(serial->dev, 0),
-                                0x22, 0x21, val, interface,
-                                NULL, 0, USB_CTRL_SET_TIMEOUT);
+                        do_send = 1;
                 }
         }
 
@@ -339,12 +337,18 @@ static int sierra_send_setup(struct usb_serial_port *port)
                         interface = 1;
                 else if (port->bulk_out_endpointAddress == 5)
                         interface = 2;
-                return usb_control_msg(serial->dev,
-                        usb_rcvctrlpipe(serial->dev, 0),
-                        0x22, 0x21, val, interface,
-                        NULL, 0, USB_CTRL_SET_TIMEOUT);
+
+                do_send = 1;
         }
-        return 0;
+        if (!do_send)
+                return 0;
+
+        usb_autopm_get_interface(serial->interface);
+        retval = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
+                0x22, 0x21, val, interface, NULL, 0, USB_CTRL_SET_TIMEOUT);
+        usb_autopm_put_interface(serial->interface);
+
+        return retval;
 }
 
 static void sierra_set_termios(struct tty_struct *tty,