[3.11.y.z extended stable] Patch "USB: option: fix runtime PM handling" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    USB: option: fix runtime PM handling

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From da613c91cc2e93ba7f9d925a7bce6d3383f120c1 Mon Sep 17 00:00:00 2001
From: Johan Hovold <jhovold at gmail.com>
Date: Mon, 26 May 2014 19:23:10 +0200
Subject: USB: option: fix runtime PM handling

commit acf47d4f9c39b1cba467aa9442fc2efe0b1da741 upstream.

Fix potential I/O while runtime suspended due to missing PM operations
in send_setup.

Fixes: 383cedc3bb43 ("USB: serial: full autosuspend support for the
option driver")

Signed-off-by: Johan Hovold <jhovold at gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/usb/serial/option.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index 948a19f0cdf7..70ede84f4f6b 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -1925,6 +1925,7 @@ static int option_send_setup(struct usb_serial_port *port)
 	struct option_private *priv = intfdata->private;
 	struct usb_wwan_port_private *portdata;
 	int val = 0;
+	int res;

 	portdata = usb_get_serial_port_data(port);

@@ -1933,9 +1934,17 @@ static int option_send_setup(struct usb_serial_port *port)
 	if (portdata->rts_state)
 		val |= 0x02;

-	return usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
+	res = usb_autopm_get_interface(serial->interface);
+	if (res)
+		return res;
+
+	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 				0x22, 0x21, val, priv->bInterfaceNumber, NULL,
 				0, USB_CTRL_SET_TIMEOUT);
+
+	usb_autopm_put_interface(serial->interface);
+
+	return res;
 }

 MODULE_AUTHOR(DRIVER_AUTHOR);
--
1.9.1