of/platform: Handle of_populate drivers in notifier

When using overlays with drivers calling of_populate the notifier
will try to create the device twice. Using the populated bit
before proceeding protects against this.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>

drivers/of/platform.c

@@ -566,6 +566,10 @@ static int of_platform_notify(struct notifier_block *nb,
 		if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
 			return NOTIFY_OK;	/* not for us */
 
+		/* already populated? (driver using of_populate manually) */
+		if (of_node_check_flag(rd->dn, OF_POPULATED))
+			return NOTIFY_OK;
+
 		/* pdev_parent may be NULL when no bus platform device */
 		pdev_parent = of_find_device_by_node(rd->dn->parent);
 		pdev = of_platform_device_create(rd->dn, NULL,
@@ -581,6 +585,11 @@ static int of_platform_notify(struct notifier_block *nb,
 		break;
 
 	case OF_RECONFIG_CHANGE_REMOVE:
+
+		/* already depopulated? */
+		if (!of_node_check_flag(rd->dn, OF_POPULATED))
+			return NOTIFY_OK;
+
 		/* find our device by node */
 		pdev = of_find_device_by_node(rd->dn);
 		if (pdev == NULL)