@@ -5046,6 +5046,80 @@ void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode)
}
EXPORT_SYMBOL_GPL(set_secondary_fwnode);
+/**
+ * device_remove_of_node - Remove an of_node from a device
+ * @dev: device whose device-tree node is being removed
+ */
+void device_remove_of_node(struct device *dev)
+{
+ dev = get_device(dev);
+ if (!dev)
+ return;
+
+ if (!dev->of_node)
+ goto end;
+
+ sysfs_remove_link(&dev->kobj, "of_node");
+
+ if (dev->fwnode == of_fwnode_handle(dev->of_node))
+ dev->fwnode = NULL;
+
+ of_node_put(dev->of_node);
+ dev->of_node = NULL;
+
+end:
+ put_device(dev);
+}
+EXPORT_SYMBOL_GPL(device_remove_of_node);
+
+/**
+ * device_add_of_node - Add an of_node to an existing device
+ * @dev: device whose device-tree node is being added
+ * @of_node: of_node to add
+ */
+void device_add_of_node(struct device *dev, struct device_node *of_node)
+{
+ int ret;
+
+ if (!of_node)
+ return;
+
+ dev = get_device(dev);
+ if (!dev)
+ return;
+
+ if (dev->of_node) {
+ dev_warn(dev, "Replace node %pOF with %pOF\n", dev->of_node, of_node);
+ device_remove_of_node(dev);
+ }
+
+ dev->of_node = of_node_get(of_node);
+
+ if (!dev->fwnode)
+ dev->fwnode = of_fwnode_handle(of_node);
+
+ if (!dev->p) {
+ /*
+ * device_add() was not previously called.
+ * The of_node link will be created when device_add() is called.
+ */
+ goto end;
+ }
+
+ /*
+ * device_add() was previously called and so the of_node link was not
+ * created by device_add_class_symlinks().
+ * Create this link now.
+ */
+ ret = sysfs_create_link(&dev->kobj, of_node_kobj(of_node), "of_node");
+ if (ret)
+ dev_warn(dev, "Error %d creating of_node link\n", ret);
+
+end:
+ put_device(dev);
+}
+EXPORT_SYMBOL_GPL(device_add_of_node);
+
/**
* device_set_of_node_from_dev - reuse device-tree node of another device
* @dev: device whose device-tree node is being set
@@ -1128,6 +1128,8 @@ int device_offline(struct device *dev);
int device_online(struct device *dev);
void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
+void device_add_of_node(struct device *dev, struct device_node *of_node);
+void device_remove_of_node(struct device *dev);
void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
void device_set_node(struct device *dev, struct fwnode_handle *fwnode);
An of_node can be duplicated from an existing device using device_set_of_node_from_dev() or initialized using device_set_node() In both cases, these functions have to be called before the device_add() call in order to have the of_node link created in the device sysfs directory. Further more, these function cannot prevent any of_node and/or fwnode overwrites. When adding an of_node on an already present device, the following operations need to be done: - Attach the of_node if no of_node were already attached - Attach the of_node as a fwnode if no fwnode were already attached - Create the of_node sysfs link if needed This is the purpose of device_add_of_node(). device_remove_of_node() reverts the operations done by device_add_of_node(). Cc: stable@vger.kernel.org Signed-off-by: Herve Codina <herve.codina@bootlin.com> --- drivers/base/core.c | 74 ++++++++++++++++++++++++++++++++++++++++++ include/linux/device.h | 2 ++ 2 files changed, 76 insertions(+)