patch "Revert "USB / PM: Allow USB devices to remain runtime-suspended when" added to usb-linus

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    Revert "USB / PM: Allow USB devices to remain runtime-suspended when

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


>From 9be427efc764464fbcbc1ca3f0d34f575cb0f037 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Mon, 2 May 2016 15:35:57 +0200
Subject: Revert "USB / PM: Allow USB devices to remain runtime-suspended when
 sleeping"

This reverts commit e3345db85068ddb937fc0ba40dfc39c293dad977, which
broke system resume for a large class of devices.

Devices that after having been reset during resume need to be rebound
due to a missing reset_resume callback, are now left in a suspended
state. This specifically broke resume of common USB-serial devices,
which are now unusable after system suspend (until disconnected and
reconnected) when USB persist is enabled.

During resume, usb_resume_interface will set the needs_binding flag for
such interfaces, but unlike system resume, run-time resume does not
honour it.

Cc: stable <stable@vger.kernel.org>	# 4.5
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/core/port.c | 6 ------
 drivers/usb/core/usb.c  | 8 +-------
 2 files changed, 1 insertion(+), 13 deletions(-)

diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index 14718a9ffcfb..460c855be0d0 100644
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -249,18 +249,12 @@ static int usb_port_runtime_suspend(struct device *dev)
 
 	return retval;
 }
-
-static int usb_port_prepare(struct device *dev)
-{
-	return 1;
-}
 #endif
 
 static const struct dev_pm_ops usb_port_pm_ops = {
 #ifdef CONFIG_PM
 	.runtime_suspend =	usb_port_runtime_suspend,
 	.runtime_resume =	usb_port_runtime_resume,
-	.prepare =		usb_port_prepare,
 #endif
 };
 
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index dcb85e3cd5a7..479187c32571 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -312,13 +312,7 @@ static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 
 static int usb_dev_prepare(struct device *dev)
 {
-	struct usb_device *udev = to_usb_device(dev);
-
-	/* Return 0 if the current wakeup setting is wrong, otherwise 1 */
-	if (udev->do_remote_wakeup != device_may_wakeup(dev))
-		return 0;
-
-	return 1;
+	return 0;		/* Implement eventually? */
 }
 
 static void usb_dev_complete(struct device *dev)
-- 
2.8.2