Merge branch 'r8152-runtime-mac-changes'

Mario Limonciello says:

====================
r8152: Support runtime changes of vendor mac passthu policy

On some platforms ACPI method `\\_SB.AMAC` is dynamic and changes to it can
influence changing the behavior of MAC pass through and what MAC address is used.

When running USB reset, re-read the MAC address to use to support tools that
change the policy.

This is quite similar to using `SIOCSIFHWADDR` except that the actual MAC to use
comes from ASL rather than from userspace.

Changes from v1:
 * Remove an extra unneeded `ether_addr_copy` call
 * Use `dev_set_mac_address` to ensure all notifiers are called
 * Shuffle functions to allow code re-use.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/r8152.c

@@ -1212,7 +1212,6 @@ static int vendor_mac_passthru_addr_read(struct r8152 *tp, struct sockaddr *sa)
 		goto amacout;
 	}
 	memcpy(sa->sa_data, buf, 6);
-	ether_addr_copy(tp->netdev->dev_addr, sa->sa_data);
 	netif_info(tp, probe, tp->netdev,
 		   "Using pass-thru MAC addr %pM\n", sa->sa_data);
 
@@ -1221,39 +1220,51 @@ static int vendor_mac_passthru_addr_read(struct r8152 *tp, struct sockaddr *sa)
 	return ret;
 }
 
-static int set_ethernet_addr(struct r8152 *tp)
+static int determine_ethernet_addr(struct r8152 *tp, struct sockaddr *sa)
 {
 	struct net_device *dev = tp->netdev;
-	struct sockaddr sa;
 	int ret;
 
 	if (tp->version == RTL_VER_01) {
-		ret = pla_ocp_read(tp, PLA_IDR, 8, sa.sa_data);
+		ret = pla_ocp_read(tp, PLA_IDR, 8, sa->sa_data);
 	} else {
 		/* if device doesn't support MAC pass through this will
 		 * be expected to be non-zero
 		 */
-		ret = vendor_mac_passthru_addr_read(tp, &sa);
+		ret = vendor_mac_passthru_addr_read(tp, sa);
 		if (ret < 0)
-			ret = pla_ocp_read(tp, PLA_BACKUP, 8, sa.sa_data);
+			ret = pla_ocp_read(tp, PLA_BACKUP, 8, sa->sa_data);
 	}
 
 	if (ret < 0) {
 		netif_err(tp, probe, dev, "Get ether addr fail\n");
-	} else if (!is_valid_ether_addr(sa.sa_data)) {
+	} else if (!is_valid_ether_addr(sa->sa_data)) {
 		netif_err(tp, probe, dev, "Invalid ether addr %pM\n",
-			  sa.sa_data);
+			  sa->sa_data);
 		eth_hw_addr_random(dev);
-		ether_addr_copy(sa.sa_data, dev->dev_addr);
-		ret = rtl8152_set_mac_address(dev, &sa);
+		ether_addr_copy(sa->sa_data, dev->dev_addr);
 		netif_info(tp, probe, dev, "Random ether addr %pM\n",
-			   sa.sa_data);
-	} else {
+			   sa->sa_data);
+		return 0;
+	}
+
+	return ret;
+}
+
+static int set_ethernet_addr(struct r8152 *tp)
+{
+	struct net_device *dev = tp->netdev;
+	struct sockaddr sa;
+	int ret;
+
+	ret = determine_ethernet_addr(tp, &sa);
+	if (ret < 0)
+		return ret;
+
 	if (tp->version == RTL_VER_01)
 		ether_addr_copy(dev->dev_addr, sa.sa_data);
 	else
 		ret = rtl8152_set_mac_address(dev, &sa);
-	}
 
 	return ret;
 }
@@ -4264,10 +4275,18 @@ static int rtl8152_post_reset(struct usb_interface *intf)
 {
 	struct r8152 *tp = usb_get_intfdata(intf);
 	struct net_device *netdev;
+	struct sockaddr sa;
 
 	if (!tp)
 		return 0;
 
+	/* reset the MAC adddress in case of policy change */
+	if (determine_ethernet_addr(tp, &sa) >= 0) {
+		rtnl_lock();
+		dev_set_mac_address (tp->netdev, &sa, NULL);
+		rtnl_unlock();
+	}
+
 	netdev = tp->netdev;
 	if (!netif_running(netdev))
 		return 0;