DMA_CHAN_BUS_MODE
value = readl(ioaddr + DMA_CHAN_BUS_MODE(chan));
writel(value, ioaddr + DMA_CHAN_BUS_MODE(chan));
value = readl(ioaddr + DMA_CHAN_BUS_MODE(chan));
writel(value, ioaddr + DMA_CHAN_BUS_MODE(chan));