ASPEED_I2C_FUN_CTRL_REG
writel(0, bus->base + ASPEED_I2C_FUN_CTRL_REG);
func_ctrl_reg_val = readl(bus->base + ASPEED_I2C_FUN_CTRL_REG);
writel(func_ctrl_reg_val, bus->base + ASPEED_I2C_FUN_CTRL_REG);
func_ctrl_reg_val = readl(bus->base + ASPEED_I2C_FUN_CTRL_REG);
writel(func_ctrl_reg_val, bus->base + ASPEED_I2C_FUN_CTRL_REG);
writel(0, bus->base + ASPEED_I2C_FUN_CTRL_REG);
writel(readl(bus->base + ASPEED_I2C_FUN_CTRL_REG) | fun_ctrl_reg,
bus->base + ASPEED_I2C_FUN_CTRL_REG);