USB: EHCI: add pointer to end of async-unlink list

This patch (as1570) adds a pointer for the end of ehci-hcd's
async-unlink list.  The list (which is actually a queue) is singly
linked, so having a pointer to its end makes adding new entries easier
-- there's no longer any need to scan through the whole list.

In principle it could be changed to a standard doubly-linked list.  It
turns out that doing so actually makes the code less clear, so I'm
leaving it as is.

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

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 3c6c07c0956a..475f23e10bbf 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -82,6 +82,7 @@ struct ehci_hcd {			/* one per controller */
         struct ehci_qh          *async;
         struct ehci_qh          *dummy;         /* For AMD quirk use */
         struct ehci_qh          *async_unlink;
+        struct ehci_qh          *async_unlink_last;
         struct ehci_qh          *qh_scan_next;
         unsigned                scanning : 1;