firewire: Implement functionality to stop isochronous DMA contexts.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-iso.c b/drivers/firewire/fw-iso.c
index d84792f..1605e11 100644
--- a/drivers/firewire/fw-iso.c
+++ b/drivers/firewire/fw-iso.c
@@ -155,3 +155,10 @@
 	return card->driver->queue_iso(ctx, packet, buffer, payload);
 }
 EXPORT_SYMBOL(fw_iso_context_queue);
+
+int
+fw_iso_context_stop(struct fw_iso_context *ctx)
+{
+	return ctx->card->driver->stop_iso(ctx);
+}
+EXPORT_SYMBOL(fw_iso_context_stop);