[PATCH v2 3/7] of: resolver: Add export_symbols in of_resolve_phandles() parameters

[Herve Codina <herve.codina@bootlin.com>]

In order to prepare the introduction of the export symbols node
handling, add a export_symbols parameter in of_resolve_phandles().

The export_symbols is the export symbols device tree node the resolver
will use for the overlay symbols resolution.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Tested-by: Ayush Singh <ayush@beagleboard.org>
---
 drivers/of/of_private.h | 2 +-
 drivers/of/overlay.c    | 2 +-
 drivers/of/resolver.c   | 9 +++++++--
 drivers/of/unittest.c   | 4 ++--
 4 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index df0bb00349e0..cf68edb873ab 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -94,7 +94,7 @@ static inline void __of_detach_node_sysfs(struct device_node *np) {}
 #endif
 
 #if defined(CONFIG_OF_RESOLVE)
-int of_resolve_phandles(struct device_node *tree);
+int of_resolve_phandles(struct device_node *tree, const struct device_node *export_symbols);
 #endif
 
 void __of_phandle_cache_inv_entry(phandle handle);
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
index 1af6f52d0708..aa1b97e634aa 100644
--- a/drivers/of/overlay.c
+++ b/drivers/of/overlay.c
@@ -919,7 +919,7 @@ static int of_overlay_apply(struct overlay_changeset *ovcs,
 {
 	int ret = 0, ret_revert, ret_tmp;
 
-	ret = of_resolve_phandles(ovcs->overlay_root);
+	ret = of_resolve_phandles(ovcs->overlay_root, NULL);
 	if (ret)
 		goto out;
 
diff --git a/drivers/of/resolver.c b/drivers/of/resolver.c
index 2c7a3b479b15..5c492711b21f 100644
--- a/drivers/of/resolver.c
+++ b/drivers/of/resolver.c
@@ -237,7 +237,8 @@ static int get_phandle_from_symbols_node(const struct device_node *tree_symbols,
 /**
  * of_resolve_phandles - Relocate and resolve overlay against live tree
  *
- * @overlay:	Pointer to devicetree overlay to relocate and resolve
+ * @overlay:		Pointer to devicetree overlay to relocate and resolve
+ * @export_symbols:	Pointer to devicetree export symbols node.
  *
  * Modify (relocate) values of local phandles in @overlay to a range that
  * does not conflict with the live expanded devicetree.  Update references
@@ -257,6 +258,10 @@ static int get_phandle_from_symbols_node(const struct device_node *tree_symbols,
  * corresponding to that symbol in the live tree.  Update the references in
  * the overlay with the phandle values in the live tree.
  *
+ * @export_symbols can be use in this references update. The resolver tries
+ * first to find a match in the @export_symbols. If not found, it uses the
+ * "__symbol__" node in the live tree.
+ *
  * @overlay must be detached.
  *
  * Resolving and applying @overlay to the live expanded devicetree must be
@@ -267,7 +272,7 @@ static int get_phandle_from_symbols_node(const struct device_node *tree_symbols,
  *
  * Return: %0 on success or a negative error value on error.
  */
-int of_resolve_phandles(struct device_node *overlay)
+int of_resolve_phandles(struct device_node *overlay, const struct device_node *export_symbols)
 {
 	struct device_node *child, *overlay_fixups;
 	struct device_node __free(device_node) *local_fixups = NULL;
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 64d301893af7..620237365566 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -2026,7 +2026,7 @@ static int __init unittest_data_add(void)
 	 */
 	of_overlay_mutex_lock();
 
-	rc = of_resolve_phandles(unittest_data_node);
+	rc = of_resolve_phandles(unittest_data_node, NULL);
 	if (rc) {
 		pr_err("%s: Failed to resolve phandles (rc=%i)\n", __func__, rc);
 		of_overlay_mutex_unlock();
@@ -3915,7 +3915,7 @@ static __init void of_unittest_overlay_high_level(void)
 	 * because kmalloc() was not yet available.
 	 */
 	of_overlay_mutex_lock();
-	of_resolve_phandles(overlay_base_root);
+	of_resolve_phandles(overlay_base_root, NULL);
 	of_overlay_mutex_unlock();
 
 
-- 
2.49.0