AST_VHUB_EP1_STS_CHG
writel(0, vhub->regs + AST_VHUB_EP1_STS_CHG);
u32 reg = readl(vhub->regs + AST_VHUB_EP1_STS_CHG);
writel(reg, vhub->regs + AST_VHUB_EP1_STS_CHG);
writel(0, vhub->regs + AST_VHUB_EP1_STS_CHG);