net: phy: marvell10g: add thermal hwmon device

Add a thermal monitoring device for the Marvell 88x3310, which updates
once a second.  We also need to hook into the suspend/resume mechanism
to ensure that the thermal monitoring is reconfigured when we resume.
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/marvell10g.c

@@ -21,8 +21,10 @@
  * If both the fiber and copper ports are connected, the first to gain
  * link takes priority and the other port is completely locked out.
  */
-#include <linux/phy.h>
+#include <linux/ctype.h>
+#include <linux/hwmon.h>
 #include <linux/marvell_phy.h>
+#include <linux/phy.h>
 
 enum {
 	MV_PCS_BASE_T		= 0x0000,
@@ -40,6 +42,19 @@ enum {
 	 */
 	MV_AN_CTRL1000		= 0x8000, /* 1000base-T control register */
 	MV_AN_STAT1000		= 0x8001, /* 1000base-T status register */
+
+	/* Vendor2 MMD registers */
+	MV_V2_TEMP_CTRL		= 0xf08a,
+	MV_V2_TEMP_CTRL_MASK	= 0xc000,
+	MV_V2_TEMP_CTRL_SAMPLE	= 0x0000,
+	MV_V2_TEMP_CTRL_DISABLE	= 0xc000,
+	MV_V2_TEMP		= 0xf08c,
+	MV_V2_TEMP_UNKNOWN	= 0x9600, /* unknown function */
+};
+
+struct mv3310_priv {
+	struct device *hwmon_dev;
+	char *hwmon_name;
 };
 
 static int mv3310_modify(struct phy_device *phydev, int devad, u16 reg,
@@ -60,17 +75,180 @@ static int mv3310_modify(struct phy_device *phydev, int devad, u16 reg,
 	return ret < 0 ? ret : 1;
 }
 
+#ifdef CONFIG_HWMON
+static umode_t mv3310_hwmon_is_visible(const void *data,
+				       enum hwmon_sensor_types type,
+				       u32 attr, int channel)
+{
+	if (type == hwmon_chip && attr == hwmon_chip_update_interval)
+		return 0444;
+	if (type == hwmon_temp && attr == hwmon_temp_input)
+		return 0444;
+	return 0;
+}
+
+static int mv3310_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+			     u32 attr, int channel, long *value)
+{
+	struct phy_device *phydev = dev_get_drvdata(dev);
+	int temp;
+
+	if (type == hwmon_chip && attr == hwmon_chip_update_interval) {
+		*value = MSEC_PER_SEC;
+		return 0;
+	}
+
+	if (type == hwmon_temp && attr == hwmon_temp_input) {
+		temp = phy_read_mmd(phydev, MDIO_MMD_VEND2, MV_V2_TEMP);
+		if (temp < 0)
+			return temp;
+
+		*value = ((temp & 0xff) - 75) * 1000;
+
+		return 0;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static const struct hwmon_ops mv3310_hwmon_ops = {
+	.is_visible = mv3310_hwmon_is_visible,
+	.read = mv3310_hwmon_read,
+};
+
+static u32 mv3310_hwmon_chip_config[] = {
+	HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL,
+	0,
+};
+
+static const struct hwmon_channel_info mv3310_hwmon_chip = {
+	.type = hwmon_chip,
+	.config = mv3310_hwmon_chip_config,
+};
+
+static u32 mv3310_hwmon_temp_config[] = {
+	HWMON_T_INPUT,
+	0,
+};
+
+static const struct hwmon_channel_info mv3310_hwmon_temp = {
+	.type = hwmon_temp,
+	.config = mv3310_hwmon_temp_config,
+};
+
+static const struct hwmon_channel_info *mv3310_hwmon_info[] = {
+	&mv3310_hwmon_chip,
+	&mv3310_hwmon_temp,
+	NULL,
+};
+
+static const struct hwmon_chip_info mv3310_hwmon_chip_info = {
+	.ops = &mv3310_hwmon_ops,
+	.info = mv3310_hwmon_info,
+};
+
+static int mv3310_hwmon_config(struct phy_device *phydev, bool enable)
+{
+	u16 val;
+	int ret;
+
+	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, MV_V2_TEMP,
+			    MV_V2_TEMP_UNKNOWN);
+	if (ret < 0)
+		return ret;
+
+	val = enable ? MV_V2_TEMP_CTRL_SAMPLE : MV_V2_TEMP_CTRL_DISABLE;
+	ret = mv3310_modify(phydev, MDIO_MMD_VEND2, MV_V2_TEMP_CTRL,
+			    MV_V2_TEMP_CTRL_MASK, val);
+
+	return ret < 0 ? ret : 0;
+}
+
+static void mv3310_hwmon_disable(void *data)
+{
+	struct phy_device *phydev = data;
+
+	mv3310_hwmon_config(phydev, false);
+}
+
+static int mv3310_hwmon_probe(struct phy_device *phydev)
+{
+	struct device *dev = &phydev->mdio.dev;
+	struct mv3310_priv *priv = dev_get_drvdata(&phydev->mdio.dev);
+	int i, j, ret;
+
+	priv->hwmon_name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
+	if (!priv->hwmon_name)
+		return -ENODEV;
+
+	for (i = j = 0; priv->hwmon_name[i]; i++) {
+		if (isalnum(priv->hwmon_name[i])) {
+			if (i != j)
+				priv->hwmon_name[j] = priv->hwmon_name[i];
+			j++;
+		}
+	}
+	priv->hwmon_name[j] = '\0';
+
+	ret = mv3310_hwmon_config(phydev, true);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action_or_reset(dev, mv3310_hwmon_disable, phydev);
+	if (ret)
+		return ret;
+
+	priv->hwmon_dev = devm_hwmon_device_register_with_info(dev,
+				priv->hwmon_name, phydev,
+				&mv3310_hwmon_chip_info, NULL);
+
+	return PTR_ERR_OR_ZERO(priv->hwmon_dev);
+}
+#else
+static inline int mv3310_hwmon_config(struct phy_device *phydev, bool enable)
+{
+	return 0;
+}
+
+static int mv3310_hwmon_probe(struct phy_device *phydev)
+{
+	return 0;
+}
+#endif
+
 static int mv3310_probe(struct phy_device *phydev)
 {
+	struct mv3310_priv *priv;
 	u32 mmd_mask = MDIO_DEVS_PMAPMD | MDIO_DEVS_AN;
+	int ret;
 
 	if (!phydev->is_c45 ||
 	    (phydev->c45_ids.devices_in_package & mmd_mask) != mmd_mask)
 		return -ENODEV;
 
+	priv = devm_kzalloc(&phydev->mdio.dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	dev_set_drvdata(&phydev->mdio.dev, priv);
+
+	ret = mv3310_hwmon_probe(phydev);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int mv3310_suspend(struct phy_device *phydev)
+{
 	return 0;
 }
 
+static int mv3310_resume(struct phy_device *phydev)
+{
+	return mv3310_hwmon_config(phydev, true);
+}
+
 static int mv3310_config_init(struct phy_device *phydev)
 {
 	__ETHTOOL_DECLARE_LINK_MODE_MASK(supported) = { 0, };
@@ -367,9 +545,11 @@ static struct phy_driver mv3310_drivers[] = {
 				  SUPPORTED_FIBRE |
 				  SUPPORTED_10000baseT_Full |
 				  SUPPORTED_Backplane,
-		.probe		= mv3310_probe,
 		.soft_reset	= gen10g_no_soft_reset,
 		.config_init	= mv3310_config_init,
+		.probe		= mv3310_probe,
+		.suspend	= mv3310_suspend,
+		.resume		= mv3310_resume,
 		.config_aneg	= mv3310_config_aneg,
 		.aneg_done	= mv3310_aneg_done,
 		.read_status	= mv3310_read_status,