UDMA_RX_BUFx_STATUS
udma_unset(priv, REGS_DMA_RX, UDMA_RX_BUFx_STATUS(x),
status = udma_readl(priv, REGS_DMA_RX, UDMA_RX_BUFx_STATUS(index));
UDMA_RX_BUFx_STATUS(priv->rx_next_buf),