From 2930d26b5209fbab5b81989d7b084847af89cb4f Mon Sep 17 00:00:00 2001
From: Frank Rowand <frank.rowand@sony.com>
Date: Mon, 12 Feb 2018 00:25:04 -0800
Subject: [PATCH 0937/1795] of: improve reporting invalid overlay target path

Errors while developing the patch to create of_overlay_fdt_apply()
exposed inadequate error messages to debug problems when overlay
devicetree fragment nodes contain an invalid target path.  Improve
the messages in find_target_node() to remedy this.

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
(cherry picked from commit e547c0031697a0cb5ff7f4a66754fb3e082754ff)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/of/overlay.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
index 585a5de1e329..5c64752d473b 100644
--- a/drivers/of/overlay.c
+++ b/drivers/of/overlay.c
@@ -491,20 +491,30 @@ static int build_changeset(struct overlay_changeset *ovcs)
  */
 static struct device_node *find_target_node(struct device_node *info_node)
 {
+	struct device_node *node;
 	const char *path;
 	u32 val;
 	int ret;
 
 	ret = of_property_read_u32(info_node, "target", &val);
-	if (!ret)
-		return of_find_node_by_phandle(val);
+	if (!ret) {
+		node = of_find_node_by_phandle(val);
+		if (!node)
+			pr_err("find target, node: %pOF, phandle 0x%x not found\n",
+			       info_node, val);
+		return node;
+	}
 
 	ret = of_property_read_string(info_node, "target-path", &path);
-	if (!ret)
-		return of_find_node_by_path(path);
+	if (!ret) {
+		node =  of_find_node_by_path(path);
+		if (!node)
+			pr_err("find target, node: %pOF, path '%s' not found\n",
+			       info_node, path);
+		return node;
+	}
 
-	pr_err("Failed to find target for node %p (%s)\n",
-		info_node, info_node->name);
+	pr_err("find target, node: %pOF, no target property\n", info_node);
 
 	return NULL;
 }
-- 
2.19.0