static int download_tail(long long int left, int cnt)
 {
+       struct dfu_entity *dfu_entity = dfu_get_entity(alt_setting_num);
        void *transfer_buffer = dfu_get_buf();
        int ret;
 
        debug("%s: left: %llu cnt: %d\n", __func__, left, cnt);
 
        if (left) {
-               ret = dfu_write(dfu_get_entity(alt_setting_num),
-                               transfer_buffer, left, cnt++);
+               ret = dfu_write(dfu_entity, transfer_buffer, left, cnt++);
                if (ret) {
                        error("DFU write failed [%d]: left: %llu", ret, left);
                        return ret;
         * This also frees memory malloc'ed by dfu_get_buf(), so no explicit
         * need fo call dfu_free_buf() is needed.
         */
-       ret = dfu_write(dfu_get_entity(alt_setting_num),
-                       transfer_buffer, 0, cnt);
+       ret = dfu_write(dfu_entity, transfer_buffer, 0, cnt);
        if (ret)
                error("DFU write failed [%d] cnt: %d", ret, cnt);