net: mscc: ocelot: introduce conversion helpers between port and netdev

Since the mscc_ocelot_switch_lib is common between a pure switchdev and
a DSA driver, the procedure of retrieving a net_device for a certain
port index differs, as those are registered by their individual
front-ends.

Up to now that has been dealt with by always passing the port index to
the switch library, but now, we're going to need to work with net_device
pointers from the tc-flower offload, for things like indev, or mirred.
It is not desirable to refactor that, so let's make sure that the flower
offload core has the ability to translate between a net_device and a
port index properly.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/ocelot/felix.c

@@ -810,3 +810,25 @@ const struct dsa_switch_ops felix_switch_ops = {
 	.cls_flower_stats	= felix_cls_flower_stats,
 	.port_setup_tc		= felix_port_setup_tc,
 };
+
+struct net_device *felix_port_to_netdev(struct ocelot *ocelot, int port)
+{
+	struct felix *felix = ocelot_to_felix(ocelot);
+	struct dsa_switch *ds = felix->ds;
+
+	if (!dsa_is_user_port(ds, port))
+		return NULL;
+
+	return dsa_to_port(ds, port)->slave;
+}
+
+int felix_netdev_to_port(struct net_device *dev)
+{
+	struct dsa_port *dp;
+
+	dp = dsa_port_from_netdev(dev);
+	if (IS_ERR(dp))
+		return -EINVAL;
+
+	return dp->index;
+}

drivers/net/dsa/ocelot/felix.h

@@ -52,4 +52,7 @@ struct felix {
 	resource_size_t			imdio_base;
 };
 
+struct net_device *felix_port_to_netdev(struct ocelot *ocelot, int port);
+int felix_netdev_to_port(struct net_device *dev);
+
 #endif

drivers/net/dsa/ocelot/felix_vsc9959.c

@@ -1006,6 +1006,8 @@ static u16 vsc9959_wm_enc(u16 value)
 static const struct ocelot_ops vsc9959_ops = {
 	.reset			= vsc9959_reset,
 	.wm_enc			= vsc9959_wm_enc,
+	.port_to_netdev		= felix_port_to_netdev,
+	.netdev_to_port		= felix_netdev_to_port,
 };
 
 static int vsc9959_mdio_bus_alloc(struct ocelot *ocelot)

drivers/net/dsa/ocelot/seville_vsc9953.c

@@ -1058,6 +1058,8 @@ static u16 vsc9953_wm_enc(u16 value)
 static const struct ocelot_ops vsc9953_ops = {
 	.reset			= vsc9953_reset,
 	.wm_enc			= vsc9953_wm_enc,
+	.port_to_netdev		= felix_port_to_netdev,
+	.netdev_to_port		= felix_netdev_to_port,
 };
 
 static int vsc9953_mdio_bus_alloc(struct ocelot *ocelot)

drivers/net/ethernet/mscc/ocelot.h

@@ -98,6 +98,8 @@ int ocelot_port_lag_join(struct ocelot *ocelot, int port,
 			 struct net_device *bond);
 void ocelot_port_lag_leave(struct ocelot *ocelot, int port,
 			   struct net_device *bond);
+struct net_device *ocelot_port_to_netdev(struct ocelot *ocelot, int port);
+int ocelot_netdev_to_port(struct net_device *dev);
 
 u32 ocelot_port_readl(struct ocelot_port *port, u32 reg);
 void ocelot_port_writel(struct ocelot_port *port, u32 val, u32 reg);

drivers/net/ethernet/mscc/ocelot_net.c

@@ -656,6 +656,36 @@ static const struct net_device_ops ocelot_port_netdev_ops = {
 	.ndo_do_ioctl			= ocelot_ioctl,
 };
 
+struct net_device *ocelot_port_to_netdev(struct ocelot *ocelot, int port)
+{
+	struct ocelot_port *ocelot_port = ocelot->ports[port];
+	struct ocelot_port_private *priv;
+
+	if (!ocelot_port)
+		return NULL;
+
+	priv = container_of(ocelot_port, struct ocelot_port_private, port);
+
+	return priv->dev;
+}
+
+static bool ocelot_port_dev_check(const struct net_device *dev)
+{
+	return dev->netdev_ops == &ocelot_port_netdev_ops;
+}
+
+int ocelot_netdev_to_port(struct net_device *dev)
+{
+	struct ocelot_port_private *priv;
+
+	if (!dev || !ocelot_port_dev_check(dev))
+		return -EINVAL;
+
+	priv = netdev_priv(dev);
+
+	return priv->chip_port;
+}
+
 static void ocelot_port_get_strings(struct net_device *netdev, u32 sset,
 				    u8 *data)
 {

drivers/net/ethernet/mscc/ocelot_vsc7514.c

@@ -763,6 +763,8 @@ static u16 ocelot_wm_enc(u16 value)
 static const struct ocelot_ops ocelot_ops = {
 	.reset			= ocelot_reset,
 	.wm_enc			= ocelot_wm_enc,
+	.port_to_netdev		= ocelot_port_to_netdev,
+	.netdev_to_port		= ocelot_netdev_to_port,
 };
 
 static const struct vcap_field vsc7514_vcap_es0_keys[] = {

include/soc/mscc/ocelot.h

@@ -559,6 +559,8 @@ enum ocelot_tag_prefix {
 struct ocelot;
 
 struct ocelot_ops {
+	struct net_device *(*port_to_netdev)(struct ocelot *ocelot, int port);
+	int (*netdev_to_port)(struct net_device *dev);
 	int (*reset)(struct ocelot *ocelot);
 	u16 (*wm_enc)(u16 value);
 };