> +static int qca807x_psgmii_config(struct phy_device *phydev) > +{ > + struct device_node *node = phydev->mdio.dev.of_node; > + int psgmii_az, tx_amp, ret = 0; > + u32 tx_driver_strength_dt; > + > + /* Workaround to enable AZ transmitting ability */ > + if (of_property_read_bool(node, "qcom,psgmii-az")) { > + psgmii_az = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, PSGMII_MODE_CTRL); > + psgmii_az &= ~PSGMII_MODE_CTRL_AZ_WORKAROUND_MASK; > + psgmii_az |= FIELD_PREP(PSGMII_MODE_CTRL_AZ_WORKAROUND_MASK, 0xc); > + ret = phy_write_mmd(phydev, MDIO_MMD_PMAPMD, PSGMII_MODE_CTRL, psgmii_az); > + psgmii_az = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, PSGMII_MODE_CTRL); > + } > + > + /* PSGMII/QSGMII TX amp set to DT defined value instead of default 600mV */ > + if (!of_property_read_u32(node, "qcom,tx-driver-strength", &tx_driver_strength_dt)) { > + int tx_driver_strength; > + > + switch (tx_driver_strength_dt) { > + case 140: > + tx_driver_strength = 0; > + break; > + case 160: > + tx_driver_strength = 1; > + break; > + case 180: > + tx_driver_strength = 2; > + break; > + case 200: > + tx_driver_strength = 3; > + break; > + case 220: > + tx_driver_strength = 4; > + break; > + case 240: > + tx_driver_strength = 5; > + break; > + case 260: > + tx_driver_strength = 6; > + break; > + case 280: > + tx_driver_strength = 7; > + break; > + case 300: > + tx_driver_strength = 8; > + break; > + case 320: > + tx_driver_strength = 9; > + break; > + case 400: > + tx_driver_strength = 10; > + break; > + case 500: > + tx_driver_strength = 11; > + break; > + case 600: > + tx_driver_strength = 12; > + break; > + default: > + tx_driver_strength = 12; > + break; Please return -EINVAL here. The value in DT is not valid, so you should error out. If there is no value at all, then it is O.K. to default to 12. Andrew