coresight: Fix remote endpoint parsing

When parsing the remote endpoint of an output port, we do :
     rport = of_graph_get_remote_port(ep);
     rparent = of_graph_get_remote_port_parent(ep);

and then parse the "remote_port" as if it was the remote endpoint,
which is wrong. The code worked fine because we used endpoint number
as the port number. Let us fix it and optimise a bit as:

     remote_ep = of_graph_get_remote_endpoint(ep);
     if (remote_ep)
        remote_parent = of_graph_get_port_parent(remote_ep);

and then, parse the remote_ep for the port/endpoint details.

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hwtracing/coresight/of_coresight.c

@@ -134,7 +134,7 @@ static int of_coresight_parse_endpoint(struct device *dev,
 	int ret = 0;
 	struct of_endpoint endpoint, rendpoint;
 	struct device_node *rparent = NULL;
-	struct device_node *rport = NULL;
+	struct device_node *rep = NULL;
 	struct device *rdev = NULL;
 
 	do {
@@ -142,16 +142,16 @@ static int of_coresight_parse_endpoint(struct device *dev,
 		if (of_graph_parse_endpoint(ep, &endpoint))
 			break;
 		/*
-		 * Get a handle on the remote port and parent
-		 * attached to it.
+		 * Get a handle on the remote endpoint and the device it is
+		 * attached to.
 		 */
-		rparent = of_graph_get_remote_port_parent(ep);
+		rep = of_graph_get_remote_endpoint(ep);
+		if (!rep)
+			break;
+		rparent = of_graph_get_port_parent(rep);
 		if (!rparent)
 			break;
-		rport = of_graph_get_remote_port(ep);
-		if (!rport)
-			break;
-		if (of_graph_parse_endpoint(rport, &rendpoint))
+		if (of_graph_parse_endpoint(rep, &rendpoint))
 			break;
 
 		/* If the remote device is not available, defer probing */
@@ -165,15 +165,15 @@ static int of_coresight_parse_endpoint(struct device *dev,
 		pdata->child_names[i] = devm_kstrdup(dev,
 						     dev_name(rdev),
 						     GFP_KERNEL);
-		pdata->child_ports[i] = rendpoint.id;
+		pdata->child_ports[i] = rendpoint.port;
 		/* Connection record updated */
 		ret = 1;
 	} while (0);
 
 	if (rparent)
 		of_node_put(rparent);
-	if (rport)
-		of_node_put(rport);
+	if (rep)
+		of_node_put(rep);
 	if (rdev)
 		put_device(rdev);