tree f5221b8296a245cb9f3e3f84801b1d5d8feb12f9
parent 272b98c6455f00884f0350f775c5342358ebb73f
author Alan Stern <stern@rowland.harvard.edu> 1378231123 -0400
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1379436564 -0700

USB: see if URB comes from a completion handler

Now that URBs can be completed inside tasklets, we need a way of
determining whether a completion handler for a given endpoint is
currently running.  Otherwise it's not possible to maintain the API
guarantee about keeping isochronous streams synchronous when an
underrun occurs.

This patch adds a field and a routine to check whether a completion
handler for a periodic endpoint is running.  At the moment no
analogous routine appears to be necessary for async endpoints, but one
can always be added.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>