diff mbox series

[v4,05/16] of: changeset: Add of_changeset_node_move method

Message ID 20180220231046.32638-6-laurent.pinchart+renesas@ideasonboard.com
State Deferred, archived
Headers show
Series R-Car DU: Convert LVDS code to bridge driver | expand

Commit Message

Laurent Pinchart Feb. 20, 2018, 11:10 p.m. UTC 
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>

Adds a changeset helper for moving a subtree to a different place
in the running tree. This is useful in advances cases of dynamic
device tree construction.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
---
 drivers/of/dynamic.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/of.h   |  9 +++++++
 2 files changed, 75 insertions(+)

Comments

Rob Herring Feb. 21, 2018, 11:20 p.m. UTC | #1 
On Tue, Feb 20, 2018 at 5:10 PM, Laurent Pinchart
<laurent.pinchart+renesas@ideasonboard.com> wrote:
> From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
>
> Adds a changeset helper for moving a subtree to a different place
> in the running tree. This is useful in advances cases of dynamic
> device tree construction.

This one I'm not real clear on when we'd use this and we don't have
any user, so lets drop it for now.

Rob
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Laurent Pinchart Feb. 21, 2018, 11:40 p.m. UTC | #2 
Hi Rob,

On Thursday, 22 February 2018 01:20:36 EET Rob Herring wrote:
> On Tue, Feb 20, 2018 at 5:10 PM, Laurent Pinchart wrote:
> > From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
> > 
> > Adds a changeset helper for moving a subtree to a different place
> > in the running tree. This is useful in advances cases of dynamic
> > device tree construction.
> 
> This one I'm not real clear on when we'd use this and we don't have
> any user, so lets drop it for now.

OK, no problem.
diff mbox series

Patch

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index 85e722ed8631..27d9057ef360 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -1132,3 +1132,69 @@  int __of_changeset_add_update_property_string_list(
 	return ret;
 }
 EXPORT_SYMBOL_GPL(__of_changeset_add_update_property_string_list);
+
+static struct device_node *
+__of_changeset_node_move_one(struct of_changeset *ocs,
+		struct device_node *np, struct device_node *new_parent)
+{
+	struct device_node *np2;
+	const char *unitname;
+	int err;
+
+	err = of_changeset_detach_node(ocs, np);
+	if (err)
+		return ERR_PTR(err);
+
+	unitname = strrchr(np->full_name, '/');
+	if (!unitname)
+		unitname = np->full_name;
+
+	np2 = __of_node_dup(np, "%s/%s",
+			new_parent->full_name, unitname);
+	if (!np2)
+		return ERR_PTR(-ENOMEM);
+	np2->parent = new_parent;
+
+	err = of_changeset_attach_node(ocs, np2);
+	if (err)
+		return ERR_PTR(err);
+
+	return np2;
+}
+
+/**
+ * of_changeset_node_move_to - Moves a subtree to a new place in
+ *                             the tree
+ *
+ * @ocs:	changeset pointer
+ * @np:		device node pointer to be moved
+ * @to:		device node of the new parent
+ *
+ * Moves a subtree to a new place in the tree.
+ * Note that a move is a safe operation because the phandles
+ * remain valid.
+ *
+ * Returns zero on success, a negative error value otherwise.
+ */
+int of_changeset_node_move(struct of_changeset *ocs,
+		struct device_node *np, struct device_node *new_parent)
+{
+	struct device_node *npc, *nppc;
+
+	/* move the root first */
+	nppc = __of_changeset_node_move_one(ocs, np, new_parent);
+	if (IS_ERR(nppc))
+		return PTR_ERR(nppc);
+
+	/* move the subtrees next */
+	for_each_child_of_node(np, npc) {
+		nppc = __of_changeset_node_move_one(ocs, npc, nppc);
+		if (IS_ERR(nppc)) {
+			of_node_put(npc);
+			return PTR_ERR(nppc);
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_changeset_node_move);
diff --git a/include/linux/of.h b/include/linux/of.h
index 7aef555f9bc2..76197bc75346 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -1328,6 +1328,9 @@  int __of_changeset_add_update_property_string_list(
 		struct of_changeset *ocs, struct device_node *np,
 		const char *name, const char **strs, int count, bool update);
 
+int of_changeset_node_move(struct of_changeset *ocs,
+	struct device_node *np, struct device_node *new_parent);
+
 #else /* CONFIG_OF_DYNAMIC */
 static inline int of_reconfig_notifier_register(struct notifier_block *nb)
 {
@@ -1390,6 +1393,12 @@  static inline int __of_changeset_add_update_property_string_list(
 	return -EINVAL;
 }
 
+static inline int of_changeset_node_move(struct of_changeset *ocs,
+		struct device_node *np, struct device_node *new_parent)
+{
+	return -EINVAL;
+}
+
 #endif /* CONFIG_OF_DYNAMIC */
 
 /**