When using temperature measurement on Marvell 88Q2XXX devices and the
reset-gpios property is set in DT, the device does a hardware reset when
interface is brought down and up again. That means that the content of
the register MDIO_MMD_PCS_MV_TEMP_SENSOR2 is reset to default and that
leads to permanent deactivation of the temperature measurement, because
activation is done in mv88q2xxx_probe. To fix this move activation of
temperature measurement to mv88q222x_config_init.

Fixes: a557a92e6881 ("net: phy: marvell-88q2xxx: add support for temperature sensor")
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Dimitri Fedrau <dima.fedrau@gmail.com>
---
Changes in v2:
- Added missing fixes tag
- Link to v1: https://lore.kernel.org/r/20250116-marvell-88q2xxx-fix-hwmon-v1-1-ee5cfda4be87@gmail.com
---
 drivers/net/phy/marvell-88q2xxx.c | 33 ++++++++++++++++++++++++++-------
 1 file changed, 26 insertions(+), 7 deletions(-)

diff --git a/drivers/net/phy/marvell-88q2xxx.c b/drivers/net/phy/marvell-88q2xxx.c
index 4494b3e39ce2b672efe49d53d7021b765def6aa6..a3996471a1c9a5d4060d5d19ce44aa70e902a83f 100644
--- a/drivers/net/phy/marvell-88q2xxx.c
+++ b/drivers/net/phy/marvell-88q2xxx.c
@@ -95,6 +95,10 @@
 
 #define MDIO_MMD_PCS_MV_TDR_OFF_CUTOFF			65246
 
+struct mv88q2xxx_priv {
+	bool enable_temp;
+};
+
 struct mmd_val {
 	int devad;
 	u32 regnum;
@@ -710,17 +714,12 @@ static const struct hwmon_chip_info mv88q2xxx_hwmon_chip_info = {
 
 static int mv88q2xxx_hwmon_probe(struct phy_device *phydev)
 {
+	struct mv88q2xxx_priv *priv = phydev->priv;
 	struct device *dev = &phydev->mdio.dev;
 	struct device *hwmon;
 	char *hwmon_name;
-	int ret;
-
-	/* Enable temperature sense */
-	ret = phy_modify_mmd(phydev, MDIO_MMD_PCS, MDIO_MMD_PCS_MV_TEMP_SENSOR2,
-			     MDIO_MMD_PCS_MV_TEMP_SENSOR2_DIS_MASK, 0);
-	if (ret < 0)
-		return ret;
 
+	priv->enable_temp = true;
 	hwmon_name = devm_hwmon_sanitize_name(dev, dev_name(dev));
 	if (IS_ERR(hwmon_name))
 		return PTR_ERR(hwmon_name);
@@ -743,6 +742,14 @@ static int mv88q2xxx_hwmon_probe(struct phy_device *phydev)
 
 static int mv88q2xxx_probe(struct phy_device *phydev)
 {
+	struct mv88q2xxx_priv *priv;
+
+	priv = devm_kzalloc(&phydev->mdio.dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	phydev->priv = priv;
+
 	return mv88q2xxx_hwmon_probe(phydev);
 }
 
@@ -810,6 +817,18 @@ static int mv88q222x_revb1_revb2_config_init(struct phy_device *phydev)
 
 static int mv88q222x_config_init(struct phy_device *phydev)
 {
+	struct mv88q2xxx_priv *priv = phydev->priv;
+	int ret;
+
+	/* Enable temperature sense */
+	if (priv->enable_temp) {
+		ret = phy_modify_mmd(phydev, MDIO_MMD_PCS,
+				     MDIO_MMD_PCS_MV_TEMP_SENSOR2,
+				     MDIO_MMD_PCS_MV_TEMP_SENSOR2_DIS_MASK, 0);
+		if (ret < 0)
+			return ret;
+	}
+
 	if (phydev->c45_ids.device_ids[MDIO_MMD_PMAPMD] == PHY_ID_88Q2220_REVB0)
 		return mv88q222x_revb0_config_init(phydev);
 	else

---
base-commit: b44e27b4df1a1cd3fd84cf26c82156ed0301575f
change-id: 20250116-marvell-88q2xxx-fix-hwmon-d6700aae9227

Best regards,
-- 
Dimitri Fedrau <dima.fedrau@gmail.com>

On Sat, Jan 18, 2025 at 07:43:43PM +0100, Dimitri Fedrau wrote:
> When using temperature measurement on Marvell 88Q2XXX devices and the
> reset-gpios property is set in DT, the device does a hardware reset when
> interface is brought down and up again. That means that the content of
> the register MDIO_MMD_PCS_MV_TEMP_SENSOR2 is reset to default and that
> leads to permanent deactivation of the temperature measurement, because
> activation is done in mv88q2xxx_probe. To fix this move activation of
> temperature measurement to mv88q222x_config_init.
> 
> Fixes: a557a92e6881 ("net: phy: marvell-88q2xxx: add support for temperature sensor")
> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> Signed-off-by: Dimitri Fedrau <dima.fedrau@gmail.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew