cal_cycle
ret = cal_cycle(phydev, MDIO_MMD_VEND1, MTK_PHY_RXADC_CTRL_RG9,
lower_ret = cal_cycle(phydev, MDIO_MMD_VEND1,
upper_ret = cal_cycle(phydev, MDIO_MMD_VEND1,
cal_cycle(phydev, MDIO_MMD_VEND1, MTK_PHY_RXADC_CTRL_RG9,
cal_cycle(phydev, MDIO_MMD_VEND1, MTK_PHY_RXADC_CTRL_RG9,