net: ethtool: Refactor identical get_ts_info implementations.

The vlan, macvlan and the bonding drivers call their "real" device driver
in order to report the time stamping capabilities.  Provide a core
ethtool helper function to avoid copy/paste in the stack.

Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: richardcochran

drivers/net/bonding/bond_main.c

@@ -5755,10 +5755,8 @@ static int bond_ethtool_get_ts_info(struct net_device *bond_dev,
 {
 	struct bonding *bond = netdev_priv(bond_dev);
 	struct ethtool_ts_info ts_info;
-	const struct ethtool_ops *ops;
 	struct net_device *real_dev;
 	bool sw_tx_support = false;
-	struct phy_device *phydev;
 	struct list_head *iter;
 	struct slave *slave;
 	int ret = 0;
@@ -5769,29 +5767,12 @@ static int bond_ethtool_get_ts_info(struct net_device *bond_dev,
 	rcu_read_unlock();
 
 	if (real_dev) {
-		ops = real_dev->ethtool_ops;
-		phydev = real_dev->phydev;
-
-		if (phy_has_tsinfo(phydev)) {
-			ret = phy_ts_info(phydev, info);
-			goto out;
-		} else if (ops->get_ts_info) {
-			ret = ops->get_ts_info(real_dev, info);
-			goto out;
-		}
+		ret = ethtool_get_ts_info_by_layer(real_dev, info);
 	} else {
 		/* Check if all slaves support software tx timestamping */
 		rcu_read_lock();
 		bond_for_each_slave_rcu(bond, slave, iter) {
-			ret = -1;
-			ops = slave->dev->ethtool_ops;
-			phydev = slave->dev->phydev;
-
-			if (phy_has_tsinfo(phydev))
-				ret = phy_ts_info(phydev, &ts_info);
-			else if (ops->get_ts_info)
-				ret = ops->get_ts_info(slave->dev, &ts_info);
-
+			ret = ethtool_get_ts_info_by_layer(slave->dev, &ts_info);
 			if (!ret && (ts_info.so_timestamping & SOF_TIMESTAMPING_TX_SOFTWARE)) {
 				sw_tx_support = true;
 				continue;
@@ -5803,15 +5784,9 @@ static int bond_ethtool_get_ts_info(struct net_device *bond_dev,
 		rcu_read_unlock();
 	}
 
-	ret = 0;
-	info->so_timestamping = SOF_TIMESTAMPING_RX_SOFTWARE |
-				SOF_TIMESTAMPING_SOFTWARE;
 	if (sw_tx_support)
 		info->so_timestamping |= SOF_TIMESTAMPING_TX_SOFTWARE;
 
-	info->phc_index = -1;
-
-out:
 	dev_put(real_dev);
 	return ret;
 }

drivers/net/macvlan.c

@@ -1086,20 +1086,8 @@ static int macvlan_ethtool_get_ts_info(struct net_device *dev,
 				       struct ethtool_ts_info *info)
 {
 	struct net_device *real_dev = macvlan_dev_real_dev(dev);
-	const struct ethtool_ops *ops = real_dev->ethtool_ops;
-	struct phy_device *phydev = real_dev->phydev;
 
-	if (phy_has_tsinfo(phydev)) {
-		return phy_ts_info(phydev, info);
-	} else if (ops->get_ts_info) {
-		return ops->get_ts_info(real_dev, info);
-	} else {
-		info->so_timestamping = SOF_TIMESTAMPING_RX_SOFTWARE |
-			SOF_TIMESTAMPING_SOFTWARE;
-		info->phc_index = -1;
-	}
-
-	return 0;
+	return ethtool_get_ts_info_by_layer(real_dev, info);
 }
 
 static netdev_features_t macvlan_fix_features(struct net_device *dev,

include/linux/ethtool.h

@@ -1043,6 +1043,14 @@ static inline int ethtool_mm_frag_size_min_to_add(u32 val_min, u32 *val_add,
 	return -EINVAL;
 }
 
+/**
+ * ethtool_get_ts_info_by_layer - Obtains time stamping capabilities from the MAC or PHY layer.
+ * @dev: pointer to net_device structure
+ * @info: buffer to hold the result
+ * Returns zero on success, non-zero otherwise.
+ */
+int ethtool_get_ts_info_by_layer(struct net_device *dev, struct ethtool_ts_info *info);
+
 /**
  * ethtool_sprintf - Write formatted string to ethtool string data
  * @data: Pointer to a pointer to the start of string to update

net/8021q/vlan_dev.c

@@ -702,20 +702,7 @@ static int vlan_ethtool_get_ts_info(struct net_device *dev,
 				    struct ethtool_ts_info *info)
 {
 	const struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
-	const struct ethtool_ops *ops = vlan->real_dev->ethtool_ops;
-	struct phy_device *phydev = vlan->real_dev->phydev;
-
-	if (phy_has_tsinfo(phydev)) {
-		return phy_ts_info(phydev, info);
-	} else if (ops->get_ts_info) {
-		return ops->get_ts_info(vlan->real_dev, info);
-	} else {
-		info->so_timestamping = SOF_TIMESTAMPING_RX_SOFTWARE |
-			SOF_TIMESTAMPING_SOFTWARE;
-		info->phc_index = -1;
-	}
-
-	return 0;
+	return ethtool_get_ts_info_by_layer(vlan->real_dev, info);
 }
 
 static void vlan_dev_get_stats64(struct net_device *dev,

net/ethtool/common.c

@@ -661,6 +661,12 @@ int ethtool_get_phc_vclocks(struct net_device *dev, int **vclock_index)
 }
 EXPORT_SYMBOL(ethtool_get_phc_vclocks);
 
+int ethtool_get_ts_info_by_layer(struct net_device *dev, struct ethtool_ts_info *info)
+{
+	return __ethtool_get_ts_info(dev, info);
+}
+EXPORT_SYMBOL(ethtool_get_ts_info_by_layer);
+
 const struct ethtool_phy_ops *ethtool_phy_ops;
 
 void ethtool_set_ethtool_phy_ops(const struct ethtool_phy_ops *ops)