net: dsa: allow reporting of standard ethtool stats for slave devices

Jakub pointed out that we have a new ethtool API for reporting device
statistics in a standardized way, via .get_eth_{phy,mac,ctrl}_stats.
Add a small amount of plumbing to allow DSA drivers to take advantage of
this when exposing statistics.
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/dsa.h

@@ -645,6 +645,12 @@ struct dsa_switch_ops {
 	int	(*get_sset_count)(struct dsa_switch *ds, int port, int sset);
 	void	(*get_ethtool_phy_stats)(struct dsa_switch *ds,
 					 int port, uint64_t *data);
+	void	(*get_eth_phy_stats)(struct dsa_switch *ds, int port,
+				     struct ethtool_eth_phy_stats *phy_stats);
+	void	(*get_eth_mac_stats)(struct dsa_switch *ds, int port,
+				     struct ethtool_eth_mac_stats *mac_stats);
+	void	(*get_eth_ctrl_stats)(struct dsa_switch *ds, int port,
+				      struct ethtool_eth_ctrl_stats *ctrl_stats);
 	void	(*get_stats64)(struct dsa_switch *ds, int port,
 				   struct rtnl_link_stats64 *s);
 	void	(*self_test)(struct dsa_switch *ds, int port,

net/dsa/slave.c

@@ -789,6 +789,37 @@ static int dsa_slave_get_sset_count(struct net_device *dev, int sset)
 	return -EOPNOTSUPP;
 }
 
+static void dsa_slave_get_eth_phy_stats(struct net_device *dev,
+					struct ethtool_eth_phy_stats *phy_stats)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_eth_phy_stats)
+		ds->ops->get_eth_phy_stats(ds, dp->index, phy_stats);
+}
+
+static void dsa_slave_get_eth_mac_stats(struct net_device *dev,
+					struct ethtool_eth_mac_stats *mac_stats)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_eth_mac_stats)
+		ds->ops->get_eth_mac_stats(ds, dp->index, mac_stats);
+}
+
+static void
+dsa_slave_get_eth_ctrl_stats(struct net_device *dev,
+			     struct ethtool_eth_ctrl_stats *ctrl_stats)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_eth_ctrl_stats)
+		ds->ops->get_eth_ctrl_stats(ds, dp->index, ctrl_stats);
+}
+
 static void dsa_slave_net_selftest(struct net_device *ndev,
 				   struct ethtool_test *etest, u64 *buf)
 {
@@ -1695,6 +1726,9 @@ static const struct ethtool_ops dsa_slave_ethtool_ops = {
 	.get_strings		= dsa_slave_get_strings,
 	.get_ethtool_stats	= dsa_slave_get_ethtool_stats,
 	.get_sset_count		= dsa_slave_get_sset_count,
+	.get_eth_phy_stats	= dsa_slave_get_eth_phy_stats,
+	.get_eth_mac_stats	= dsa_slave_get_eth_mac_stats,
+	.get_eth_ctrl_stats	= dsa_slave_get_eth_ctrl_stats,
 	.set_wol		= dsa_slave_set_wol,
 	.get_wol		= dsa_slave_get_wol,
 	.set_eee		= dsa_slave_set_eee,