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

Message ID 1358916242-24014-1-git-send-email-herton.krzesinski@canonical.com
State New
Headers show

Commit Message

Herton Ronaldo Krzesinski Jan. 23, 2013, 4:44 a.m.
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:


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



From 21c2d03c2b35f123359fb7580403559c88592761 Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oliver@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@suse.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@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",
-	} 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) {
 		if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
 			status = usb_control_msg(udev,