[PATCH net-next v1] mlxbf_gige: report unknown speed and duplex when link is down

[Chris Babroski <cbabroski@nvidia.com>]

The "Speed" and "Duplex" fields displayed by ethtool should report
"Unknown" when the link is down. Currently, the driver always reports
the initially configured link speed and duplex, regardless of the actual
link state.

Implement a get_link_ksettings() callback to update the values reported
to ethtool based on the link state. When the link is down, the driver
now reports unknown speed and duplex as expected.

Signed-off-by: Chris Babroski <cbabroski@nvidia.com>
---
 .../mellanox/mlxbf_gige/mlxbf_gige_ethtool.c  | 26 ++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_ethtool.c b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_ethtool.c
index 8b63968bbee9..c519eeb8ec48 100644
--- a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_ethtool.c
@@ -159,6 +159,30 @@ static void mlxbf_gige_get_pause_stats(struct net_device *netdev,
 	}
 }
 
+static int mlxbf_gige_get_link_ksettings(struct net_device *ndev,
+					 struct ethtool_link_ksettings *cmd)
+{
+	struct phy_device *phydev;
+	int ret;
+
+	ret = phy_ethtool_get_link_ksettings(ndev, cmd);
+	if (ret)
+		return ret;
+
+	phydev = ndev->phydev;
+	if (!phydev)
+		return -ENODEV;
+
+	mutex_lock(&phydev->lock);
+	if (!phydev->link) {
+		cmd->base.speed = SPEED_UNKNOWN;
+		cmd->base.duplex = DUPLEX_UNKNOWN;
+	}
+	mutex_unlock(&phydev->lock);
+
+	return 0;
+}
+
 const struct ethtool_ops mlxbf_gige_ethtool_ops = {
 	.get_link		= ethtool_op_get_link,
 	.get_ringparam		= mlxbf_gige_get_ringparam,
@@ -170,6 +194,6 @@ const struct ethtool_ops mlxbf_gige_ethtool_ops = {
 	.nway_reset		= phy_ethtool_nway_reset,
 	.get_pauseparam		= mlxbf_gige_get_pauseparam,
 	.get_pause_stats	= mlxbf_gige_get_pause_stats,
-	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
+	.get_link_ksettings	= mlxbf_gige_get_link_ksettings,
 	.set_link_ksettings	= phy_ethtool_set_link_ksettings,
 };

base-commit: d9104cec3e8fe4b458b74709853231385779001f
-- 
2.34.1