We accidentally return success if dmaengine_submit() fails.  The fix is
to preserve the error code from dma_submit_error().
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
        tx->callback_param = pthr;
        dma_set_unmap(tx, unmap);
 
-       if (dma_submit_error(dmaengine_submit(tx))) {
+       ret = dma_submit_error(dmaengine_submit(tx));
+       if (ret) {
                dmaengine_unmap_put(unmap);
                goto err_free_resource;
        }