QUP_IO_M_MODES
iomode = readl_relaxed(base + QUP_IO_M_MODES);
writel_relaxed(0, base + QUP_IO_M_MODES);
iomode = readl_relaxed(controller->base + QUP_IO_M_MODES);
writel_relaxed(iomode, controller->base + QUP_IO_M_MODES);