[PATCH net-next 8/8] net: dsa: mt7530: implement port_change_conduit op

[Daniel Golle]

Allow changing the CPU port affinity of user ports at runtime via
the IFLA_DSA_CONDUIT netlink attribute. This updates the port matrix
to forward to the new CPU port instead of the old one.

Signed-off-by: Daniel Golle <daniel at makrotopia.org>
---
 drivers/net/dsa/mt7530.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index c96420c291d5..2f3e734b9f53 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -3206,6 +3206,34 @@ static int mt753x_set_mac_eee(struct dsa_switch *ds, int port,
 	return 0;
 }
 
+static int
+mt753x_port_change_conduit(struct dsa_switch *ds, int port,
+			   struct net_device *conduit,
+			   struct netlink_ext_ack *extack)
+{
+	struct dsa_port *new_cpu_dp = conduit->dsa_ptr;
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	struct mt7530_priv *priv = ds->priv;
+
+	if (priv->id != ID_MT7531)
+		return -EOPNOTSUPP;
+
+	mutex_lock(&priv->reg_mutex);
+
+	/* dp->cpu_dp still points to the old CPU port */
+	priv->ports[port].pm &= ~PCR_MATRIX(BIT(dp->cpu_dp->index));
+	priv->ports[port].pm |= PCR_MATRIX(BIT(new_cpu_dp->index));
+	if (priv->ports[port].enable)
+		regmap_update_bits(priv->regmap, MT7530_PCR_P(port),
+				   PCR_MATRIX_MASK, priv->ports[port].pm);
+
+	mutex_unlock(&priv->reg_mutex);
+
+	mt7530_port_fast_age(ds, port);
+
+	return 0;
+}
+
 static void
 mt753x_conduit_state_change(struct dsa_switch *ds,
 			    const struct net_device *conduit,
@@ -3317,6 +3345,7 @@ static const struct dsa_switch_ops mt7530_switch_ops = {
 	.setup			= mt753x_setup,
 	.teardown		= mt753x_teardown,
 	.preferred_default_local_cpu_port = mt753x_preferred_default_local_cpu_port,
+	.port_change_conduit	= mt753x_port_change_conduit,
 	.get_strings		= mt7530_get_strings,
 	.get_ethtool_stats	= mt7530_get_ethtool_stats,
 	.get_sset_count		= mt7530_get_sset_count,
-- 
2.54.0