MT_DMA_CTL_DMA_DONE
q->desc[i].ctrl = cpu_to_le32(MT_DMA_CTL_DMA_DONE);
q->desc[idx].ctrl |= cpu_to_le32(MT_DMA_CTL_DMA_DONE);
else if (!(q->desc[idx].ctrl & cpu_to_le32(MT_DMA_CTL_DMA_DONE)))
q->desc[i].ctrl = cpu_to_le32(MT_DMA_CTL_DMA_DONE);