net: dsa: add support for ethtool get_rmon_stats()

Add support to allow dsa drivers to specify the .get_rmon_stats()
operation.

Signed-off-by: Clément Léger <clement.leger@bootlin.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/dsa.h

@@ -888,6 +888,9 @@ struct dsa_switch_ops {
 				     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_rmon_stats)(struct dsa_switch *ds, int port,
+				  struct ethtool_rmon_stats *rmon_stats,
+				  const struct ethtool_rmon_hist_range **ranges);
 	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

@@ -1002,6 +1002,18 @@ dsa_slave_get_eth_ctrl_stats(struct net_device *dev,
 		ds->ops->get_eth_ctrl_stats(ds, dp->index, ctrl_stats);
 }
 
+static void
+dsa_slave_get_rmon_stats(struct net_device *dev,
+			 struct ethtool_rmon_stats *rmon_stats,
+			 const struct ethtool_rmon_hist_range **ranges)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_rmon_stats)
+		ds->ops->get_rmon_stats(ds, dp->index, rmon_stats, ranges);
+}
+
 static void dsa_slave_net_selftest(struct net_device *ndev,
 				   struct ethtool_test *etest, u64 *buf)
 {
@@ -2081,6 +2093,7 @@ static const struct ethtool_ops dsa_slave_ethtool_ops = {
 	.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,
+	.get_rmon_stats		= dsa_slave_get_rmon_stats,
 	.set_wol		= dsa_slave_set_wol,
 	.get_wol		= dsa_slave_get_wol,
 	.set_eee		= dsa_slave_set_eee,