[PATCHv2 2/3] software node: Introduce device_add_software_node()

From: Heikki Krogerus
Date: Thu Oct 29 2020 - 06:59:59 EST


This helper will register a software node and then assign
it to device at the same time. The function will also make
sure that the device can't have more than one software node.

Signed-off-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
---
drivers/base/swnode.c | 45 ++++++++++++++++++++++++++++++++++++++++
include/linux/property.h | 3 +++
2 files changed, 48 insertions(+)

diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
index 595a9c240fede..0001fbea19cff 100644
--- a/drivers/base/swnode.c
+++ b/drivers/base/swnode.c
@@ -1525,6 +1525,51 @@ void fwnode_remove_software_node(struct fwnode_handle *fwnode)
}
EXPORT_SYMBOL_GPL(fwnode_remove_software_node);

+/**
+ * device_add_software_node - Assign software node to a device
+ * @dev: The device the software node is meant for.
+ * @swnode: The software node.
+ *
+ * This function will register @swnode and make it the secondary firmware node
+ * pointer of @dev. If @dev has no primary node, then @swnode will become the primary
+ * node.
+ */
+int device_add_software_node(struct device *dev, const struct software_node *swnode)
+{
+ int ret;
+
+ /* Only one software node per device. */
+ if (dev_to_swnode(dev))
+ return -EBUSY;
+
+ ret = software_node_register(swnode);
+ if (ret)
+ return ret;
+
+ set_secondary_fwnode(dev, software_node_fwnode(swnode));
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(device_add_software_node);
+
+/**
+ * device_remove_software_node - Remove device's software node
+ * @dev: The device with the software node.
+ *
+ * This function will unregister the software node of @dev.
+ */
+void device_remove_software_node(struct device *dev)
+{
+ struct swnode *swnode;
+
+ swnode = dev_to_swnode(dev);
+ if (!swnode)
+ return;
+
+ kobject_put(&swnode->kobj);
+}
+EXPORT_SYMBOL_GPL(device_remove_software_node);
+
int software_node_notify(struct device *dev, unsigned long action)
{
struct swnode *swnode;
diff --git a/include/linux/property.h b/include/linux/property.h
index 33b25c8bd4052..993638e0a0b6e 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -495,4 +495,7 @@ fwnode_create_software_node(const struct property_entry *properties,
const struct fwnode_handle *parent);
void fwnode_remove_software_node(struct fwnode_handle *fwnode);

+int device_add_software_node(struct device *dev, const struct software_node *swnode);
+void device_remove_software_node(struct device *dev);
+
#endif /* _LINUX_PROPERTY_H_ */
--
2.28.0