USB: export autosuspend delay in sysfs

This patch (as861) adds sysfs attributes to expose the autosuspend
delay value for each USB device.  If the user changes the delay from 0
(no autosuspend) to a positive value, an autosuspend is attempted.

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

diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index b0a35f4..08b5a04 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -66,11 +66,13 @@
 #ifdef CONFIG_USB_SUSPEND
 
 extern void usb_autosuspend_device(struct usb_device *udev);
+extern void usb_try_autosuspend_device(struct usb_device *udev);
 extern int usb_autoresume_device(struct usb_device *udev);
 
 #else
 
-#define usb_autosuspend_device(udev)	do {} while (0)
+#define usb_autosuspend_device(udev)		do {} while (0)
+#define usb_try_autosuspend_device(udev)	do {} while (0)
 static inline int usb_autoresume_device(struct usb_device *udev)
 {
 	return 0;