usbcore: resume device resume recursion
This patch (as717b) removes the existing recursion in hub resume code:
Resuming a hub will no longer automatically resume the devices attached
to the hub.
At the same time, it adds one level of recursion: Suspending a USB
device will automatically suspend all the device's interfaces. Failure
at an intermediate stage will cause all the already-suspended interfaces
to be resumed. Attempts to suspend or resume an interface by itself will
do nothing, although they won't return an error. Thus the regular
system-suspend and system-resume procedures should continue to work as
before; only runtime PM will be affected.
The patch also removes the code that tests state of the interfaces
before suspending a device. It's no longer needed, since everything
gets suspended together.
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 1d25cca..cc42972 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -30,6 +30,8 @@
extern int usb_host_init(void);
extern void usb_host_cleanup(void);
+extern int usb_suspend_both(struct usb_device *udev, pm_message_t msg);
+extern int usb_resume_both(struct usb_device *udev);
extern int usb_port_suspend(struct usb_device *dev);
extern int usb_port_resume(struct usb_device *dev);