Commit 0af212ba authored Jun 15, 2011 by Alan Stern Committed by Greg Kroah-Hartman Jun 15, 2011

USB: don't let errors prevent system sleep



This patch (as1464) implements the recommended policy that most errors
during suspend or hibernation should not prevent the system from going
to sleep.  In particular, failure to suspend a USB driver or a USB
device should not prevent the sleep from succeeding:

Failure to suspend a device won't matter, because the device will
automatically go into suspend mode when the USB bus stops carrying
packets.  (This might be less true for USB-3.0 devices, but let's not
worry about them now.)

Failure of a driver to suspend might lead to trouble later on when the
system wakes up, but it isn't sufficient reason to prevent the system
from going to sleep.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent cbb33004

drivers/usb/core/driver.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -1187,13 +1187,22 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
		for (i = n - 1; i >= 0; --i) {
		intf = udev->actconfig->interface[i];
		status = usb_suspend_interface(udev, intf, msg);

		/* Ignore errors during system sleep transitions */
		if (!(msg.event & PM_EVENT_AUTO))
		status = 0;
		if (status != 0)
		break;
		}
		}
		if (status == 0)
		if (status == 0) {
		status = usb_suspend_device(udev, msg);

		/* Again, ignore errors during system sleep transitions */
		if (!(msg.event & PM_EVENT_AUTO))
		status = 0;
		}

		/* If the suspend failed, resume interfaces that did get suspended */
		if (status != 0) {
		msg.event ^= (PM_EVENT_SUSPEND \| PM_EVENT_RESUME);

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