Re: [PATCH V5 1/3] of: dynamic: Add interfaces for creating device node dynamically

From: Lizhi Hou
Date: Tue Jan 03 2023 - 13:35:02 EST



On 1/2/23 05:50, Clément Léger wrote:
Le Thu, 15 Dec 2022 09:30:44 -0800,
Lizhi Hou <lizhi.hou@xxxxxxx> a écrit :

of_create_node() creates device node dynamically. The parent device node
and full name are required for creating the node. It optionally creates
an OF changeset and attaches the newly created node to the changeset. The
device node pointer and the changeset pointer can be used to add
properties to the device node and apply the node to the base tree.

of_destroy_node() frees the device node created by of_create_node(). If
an OF changeset was also created for this node, it will destroy the
changeset before freeing the device node.

Expand of_changeset APIs to handle specific types of properties.
of_changeset_add_prop_string()
of_changeset_add_prop_string_array()
of_changeset_add_prop_u32_array()

Signed-off-by: Lizhi Hou <lizhi.hou@xxxxxxx>
Signed-off-by: Sonal Santan <sonal.santan@xxxxxxx>
Signed-off-by: Max Zhen <max.zhen@xxxxxxx>
Reviewed-by: Brian Xu <brian.xu@xxxxxxx>
---
drivers/of/dynamic.c | 197 +++++++++++++++++++++++++++++++++++++++++++
include/linux/of.h | 24 ++++++
2 files changed, 221 insertions(+)

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index cd3821a6444f..067d996a9f79 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -461,6 +461,71 @@ struct device_node *__of_node_dup(const struct device_node *np,
return NULL;
}
+/**
+ * of_create_node - Dynamically create a device node
+ *
+ * @parent: Pointer to parent device node
+ * @full_name: Node full name
+ * @cset: Pointer to returning changeset
+ *
+ * Return: Pointer to the created device node or NULL in case of an error.
+ */
+struct device_node *of_create_node(struct device_node *parent,
+ const char *full_name,
+ struct of_changeset **cset)
+{
+ struct of_changeset *ocs;
+ struct device_node *np;
+ int ret;
+
+ np = __of_node_dup(NULL, full_name);
+ if (!np)
+ return NULL;
+ np->parent = parent;
+
+ if (!cset)
+ return np;
+
+ ocs = kmalloc(sizeof(*cset), GFP_KERNEL);
I started to test this series and this sizeof(*cset) is probably wrong,
it should be sizeof(*ocs) or it will yield the size of a struct
of_changeset pointer and not the struct of_changeset itself.

I will fix this. Thanks.

Lizhi