net: mvpp2: simplify maintaining enabled ports' list

'port_count' field of the mvpp2 structure holds an overall amount
of available ports, based on DT nodes status. In order to be prepared
to support other HW description, obtain the value by incrementing it
upon each successful port initialization. This allowed for simplifying
port indexing in the controller's private array, whose size is now not
dynamically allocated, but fixed to MVPP2_MAX_PORTS.

This patch simplifies creating and filling list of enabled ports and
is a part of the preparation for adding ACPI support in the mvpp2 driver.
Signed-off-by: Marcin Wojtas <mw@semihalf.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvpp2.c

@@ -865,7 +865,7 @@ struct mvpp2 {
 
 	/* List of pointers to port structures */
 	int port_count;
-	struct mvpp2_port **port_list;
+	struct mvpp2_port *port_list[MVPP2_MAX_PORTS];
 
 	/* Aggregated TXQs */
 	struct mvpp2_tx_queue *aggr_txqs;
@@ -7741,7 +7741,7 @@ static void mvpp2_port_copy_mac_addr(struct net_device *dev, struct mvpp2 *priv,
 /* Ports initialization */
 static int mvpp2_port_probe(struct platform_device *pdev,
 			    struct device_node *port_node,
-			    struct mvpp2 *priv, int index)
+			    struct mvpp2 *priv)
 {
 	struct device_node *phy_node;
 	struct phy *comphy;
@@ -7934,7 +7934,8 @@ static int mvpp2_port_probe(struct platform_device *pdev,
 	}
 	netdev_info(dev, "Using %s mac address %pM\n", mac_from, dev->dev_addr);
 
-	priv->port_list[index] = port;
+	priv->port_list[priv->port_count++] = port;
+
 	return 0;
 
 err_free_port_pcpu:
@@ -8313,28 +8314,17 @@ static int mvpp2_probe(struct platform_device *pdev)
 		goto err_mg_clk;
 	}
 
-	priv->port_count = of_get_available_child_count(dn);
-	if (priv->port_count == 0) {
-		dev_err(&pdev->dev, "no ports enabled\n");
-		err = -ENODEV;
-		goto err_mg_clk;
-	}
-
-	priv->port_list = devm_kcalloc(&pdev->dev, priv->port_count,
-				       sizeof(*priv->port_list),
-				       GFP_KERNEL);
-	if (!priv->port_list) {
-		err = -ENOMEM;
-		goto err_mg_clk;
-	}
-
 	/* Initialize ports */
-	i = 0;
 	for_each_available_child_of_node(dn, port_node) {
-		err = mvpp2_port_probe(pdev, port_node, priv, i);
+		err = mvpp2_port_probe(pdev, port_node, priv);
 		if (err < 0)
 			goto err_port_probe;
-		i++;
+	}
+
+	if (priv->port_count == 0) {
+		dev_err(&pdev->dev, "no ports enabled\n");
+		err = -ENODEV;
+		goto err_mg_clk;
 	}
 
 	/* Statistics must be gathered regularly because some of them (like