net: dsa: use cpu_switch instead of ds[0]

Now that the DSA Ethernet switches are true Linux devices, the CPU
switch is not necessarily the first one. If its address is higher than
the second switch on the same MDIO bus, its index will be 1, not 0.

Avoid any confusion by using dst->cpu_switch instead of dst->ds[0].

Signed-off-by: Vivien Didelot <[e-mail]>
Reviewed-by: Andrew Lunn <[e-mail]>
Reviewed-by: Florian Fainelli <[e-mail]>
Reviewed-by: Florian Fainelli <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/dsa/dsa.c

···
 			dsa_switch_destroy(ds);
 	}
 
-	dsa_cpu_port_ethtool_restore(dst->ds[0]);
+	dsa_cpu_port_ethtool_restore(dst->cpu_switch);
 
 	dev_put(dst->master_netdev);
 }

net/dsa/dsa2.c

···
 			return err;
 	}
 
-	if (dst->ds[0]) {
-		err = dsa_cpu_port_ethtool_setup(dst->ds[0]);
+	if (dst->cpu_switch) {
+		err = dsa_cpu_port_ethtool_setup(dst->cpu_switch);
 		if (err)
 			return err;
 	}
···
 		dsa_ds_unapply(dst, ds);
 	}
 
-	if (dst->ds[0])
-		dsa_cpu_port_ethtool_restore(dst->ds[0]);
+	if (dst->cpu_switch)
+		dsa_cpu_port_ethtool_restore(dst->cpu_switch);
 
 	pr_info("DSA: tree %d unapplied\n", dst->tree);
 	dst->applied = false;

net/dsa/slave.c

···
 					   uint64_t *data)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
-	struct dsa_switch *ds = dst->ds[0];
+	struct dsa_switch *ds = dst->cpu_switch;
 	s8 cpu_port = dst->cpu_port;
 	int count = 0;
 
···
 static int dsa_cpu_port_get_sset_count(struct net_device *dev, int sset)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
-	struct dsa_switch *ds = dst->ds[0];
+	struct dsa_switch *ds = dst->cpu_switch;
 	int count = 0;
 
 	if (dst->master_ethtool_ops.get_sset_count)
···
 				     uint32_t stringset, uint8_t *data)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
-	struct dsa_switch *ds = dst->ds[0];
+	struct dsa_switch *ds = dst->cpu_switch;
 	s8 cpu_port = dst->cpu_port;
 	int len = ETH_GSTRING_LEN;
 	int mcount = 0, count;

net/dsa/tag_brcm.c

···
 	if (unlikely(dst == NULL))
 		goto out_drop;
 
-	ds = dst->ds[0];
+	ds = dst->cpu_switch;
 
 	skb = skb_unshare(skb, GFP_ATOMIC);
 	if (skb == NULL)

net/dsa/tag_qca.c

···
 	/* This protocol doesn't support cascading multiple switches so it's
 	 * safe to assume the switch is first in the tree
 	 */
-	ds = dst->ds[0];
+	ds = dst->cpu_switch;
 	if (!ds)
 		goto out_drop;
 

net/dsa/tag_trailer.c

···
 
 	if (unlikely(dst == NULL))
 		goto out_drop;
-	ds = dst->ds[0];
+	ds = dst->cpu_switch;
 
 	skb = skb_unshare(skb, GFP_ATOMIC);
 	if (skb == NULL)