USB: break apart flush_endpoint and disable_endpoint

This patch (as988) breaks usb_hcd_endpoint_disable() apart into two
routines.  The first, usb_hcd_flush_endpoint() does the -ESHUTDOWN
unlinking of all URBs in the endpoint's queue and waits for them to
complete.  The second, usb_hcd_disable_endpoint() -- renamed for
better grammatical style -- merely calls the HCD's endpoint_disable
method.  The changeover is easy because the routine currently has only
one caller.

This separation of function will be exploited in the following patch:
When a device is suspended, the core will be able to cancel all
outstanding URBs for that device while leaving the HCD's
endpoint-related data structures intact for later.

As an added benefit, HCDs no longer need to check for existing URBs in
their endpoint_disable methods.  It is now guaranteed that there will
be none.

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

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index d638375e22e..98fcddba690 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1017,7 +1017,8 @@ void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr)
 	}
 	if (ep) {
 		ep->enabled = 0;
-		usb_hcd_endpoint_disable(dev, ep);
+		usb_hcd_flush_endpoint(dev, ep);
+		usb_hcd_disable_endpoint(dev, ep);
 	}
 }