[ 3.5.y.z extended stable ] Patch "USB: hub: handle claim of enabled remote wakeup after reset" has been added to staging queue

[Herton Ronaldo Krzesinski]

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

    USB: hub: handle claim of enabled remote wakeup after reset

to the linux-3.5.y-queue branch of the 3.5.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-3.5.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 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Herton

------

>From 21c2d03c2b35f123359fb7580403559c88592761 Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oliver at neukum.org>
Date: Thu, 29 Nov 2012 15:05:57 +0100
Subject: [PATCH] USB: hub: handle claim of enabled remote wakeup after reset

commit 07e72b95f5038cc82304b9a4a2eb7f9fc391ea68 upstream.

Some touchscreens have buggy firmware which claims
remote wakeup to be enabled after a reset. They nevertheless
crash if the feature is cleared by the host.
Add a check for reset resume before checking for
an enabled remote wakeup feature. On compliant
devices the feature must be cleared after a reset anyway.

Signed-off-by: Oliver Neukum <oneukum at suse.de>
Acked-by: Alan Stern <stern at rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 drivers/usb/core/hub.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 2532bdc..92c0229 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2840,7 +2840,7 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
 static int finish_port_resume(struct usb_device *udev)
 {
 	int	status = 0;
-	u16	devstatus;
+	u16	devstatus = 0;

 	/* caller owns the udev device lock */
 	dev_dbg(&udev->dev, "%s\n",
@@ -2885,7 +2885,13 @@ static int finish_port_resume(struct usb_device *udev)
 	if (status) {
 		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
 				status);
-	} else if (udev->actconfig) {
+	/*
+	 * There are a few quirky devices which violate the standard
+	 * by claiming to have remote wakeup enabled after a reset,
+	 * which crash if the feature is cleared, hence check for
+	 * udev->reset_resume
+	 */
+	} else if (udev->actconfig && !udev->reset_resume) {
 		le16_to_cpus(&devstatus);
 		if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
 			status = usb_control_msg(udev,
--
1.7.9.5