driver core: make software nodes available earlier

Software nodes are currently initialized in a function registered as
a postcore_initcall(). However, some devices may want to register
software nodes earlier than that (or also in a postcore_initcall() where
they're at the mercy of the link order). Move the initialization to
driver_init() making swnode available much earlier as well as making
their initialization time deterministic.

Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20260402-nokia770-gpio-swnodes-v5-3-d730db3dd299@oss.qualcomm.com
[ Fix typo in the commit message: "s/merci/mercy/". - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>

Author: Bartosz Golaszewski

drivers/base/base.h

@@ -312,6 +312,7 @@ static inline int devtmpfs_create_node(struct device *dev) { return 0; }
 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
 #endif
 
+void software_node_init(void);
 void software_node_notify(struct device *dev);
 void software_node_notify_remove(struct device *dev);
 

drivers/base/init.c

@@ -34,6 +34,7 @@ void __init driver_init(void)
 	 */
 	faux_bus_init();
 	of_core_init();
+	software_node_init();
 	platform_bus_init();
 	auxiliary_bus_init();
 	memory_dev_init();

drivers/base/swnode.c

@@ -1127,11 +1127,9 @@ void software_node_notify_remove(struct device *dev)
 	}
 }
 
-static int __init software_node_init(void)
+void __init software_node_init(void)
 {
 	swnode_kset = kset_create_and_add("software_nodes", NULL, kernel_kobj);
 	if (!swnode_kset)
-		return -ENOMEM;
-	return 0;
+		pr_err("failed to register software nodes\n");
 }
-postcore_initcall(software_node_init);