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>
2 files changed