USB: flush outstanding URBs when suspending

This patch (as989) makes usbcore flush all outstanding URBs for each
device as the device is suspended.  This will be true even when
CONFIG_USB_SUSPEND is not enabled.

In addition, an extra can_submit flag is added to the usb_device
structure.  That flag will be turned off whenever a suspend request
has been received for the device, even if the device isn't actually
suspended because CONFIG_USB_SUSPEND isn't set.

It's no longer necessary to check for the device state being equal to
USB_STATE_SUSPENDED during URB submission; that check can be replaced
by a check of the can_submit flag.  This also permits us to remove
some questionable references to the deprecated power.power_state field.

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

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index ca43a6f..ba5bbc7 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1102,9 +1102,16 @@
 		if (udev->auto_pm)
 			autosuspend_check(udev);
 
-	/* If the suspend succeeded, propagate it up the tree */
+	/* If the suspend succeeded then prevent any more URB submissions,
+	 * flush any outstanding URBs, and propagate the suspend up the tree.
+	 */
 	} else {
 		cancel_delayed_work(&udev->autosuspend);
+		udev->can_submit = 0;
+		for (i = 0; i < 16; ++i) {
+			usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
+			usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
+		}
 		if (parent)
 			usb_autosuspend_device(parent);
 	}
@@ -1154,6 +1161,7 @@
 		status = -ENODEV;
 		goto done;
 	}
+	udev->can_submit = 1;
 
 	/* Propagate the resume up the tree, if necessary */
 	if (udev->state == USB_STATE_SUSPENDED) {