USB: report submission of active URBs

This patch (as1633) changes slightly the way usbcore handled
submissions of URBs that are already active.  It will now return
-EBUSY rather than -EINVAL, and it will call WARN_ONCE to draw
people's attention to the bug.

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

1 files changed, 2 insertions, 0 deletions

diff --git a/Documentation/usb/error-codes.txt b/Documentation/usb/error-codes.txt
index 8d1e2a9ebbba..9c3eb845ebe5 100644
--- a/Documentation/usb/error-codes.txt
+++ b/Documentation/usb/error-codes.txt
@@ -21,6 +21,8 @@ Non-USB-specific:
 
 USB-specific:
 
+-EBUSY          The URB is already active.
+
 -ENODEV         specified USB-device or bus doesn't exist
 
 -ENOENT         specified interface or endpoint does not exist or