diff mbox

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

Message ID 20180220231046.32638-6-laurent.pinchart+renesas@ideasonboard.com (mailing list archive)
State Not Applicable
Delegated to: Geert Uytterhoeven
Headers show

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 (Arm) 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
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

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 */
 
 /**