RCAR_DRIF_BUF_DONE
return (buf[0]->status & buf[1]->status & RCAR_DRIF_BUF_DONE);
ch->buf[idx].status |= RCAR_DRIF_BUF_DONE;
rcar_drif_bufs_clear(buf, RCAR_DRIF_BUF_DONE);