1 // SPDX-License-Identifier: GPL-2.0
28  * of_node_get() - Increment refcount of a node
29  * @node:	Node to inc refcount, NULL is supported to simplify writing of
32  * Return: The node with refcount incremented.
34 struct device_node *of_node_get(struct device_node *node)  in of_node_get()  argument
36 	if (node)  in of_node_get()
37 		kobject_get(&node->kobj);  in of_node_get()
38 	return node;  in of_node_get()
43  * of_node_put() - Decrement refcount of a node
44  * @node:	Node to dec refcount, NULL is supported to simplify writing of
47 void of_node_put(struct device_node *node)  in of_node_put()  argument
49 	if (node)  in of_node_put()
50 		kobject_put(&node->kobj);  in of_node_put()
77 #define _do_print(func, prefix, action, node, prop, ...) ({	\  argument
78 	func("changeset: " prefix "%-15s %pOF%s%s\n",		\
79 	     ##__VA_ARGS__, action_names[action], node,		\
80 	     prop ? ":" : "", prop ? prop->name : "");		\
90 	of_changeset_action_debug("notify: ", action, pr->dn, pr->prop);  in of_reconfig_notify()
97  * of_reconfig_get_state_change()	- Returns new state of device
98  * @action	- action of the of notifier
99  * @arg		- argument of the of notifier
101  * Returns the new state of a device based on the notifier used.
109 	struct property *prop, *old_prop = NULL;  in of_reconfig_get_state_change()
112 	/* figure out if a device should be created or destroyed */  in of_reconfig_get_state_change()
116 		prop = of_find_property(pr->dn, "status", NULL);  in of_reconfig_get_state_change()
120 		prop = pr->prop;  in of_reconfig_get_state_change()
123 		prop = pr->prop;  in of_reconfig_get_state_change()
124 		old_prop = pr->old_prop;  in of_reconfig_get_state_change()
131 	status_state = -1;  in of_reconfig_get_state_change()
132 	old_status_state = -1;  in of_reconfig_get_state_change()
133 	prev_state = -1;  in of_reconfig_get_state_change()
134 	new_state = -1;  in of_reconfig_get_state_change()
136 	if (prop && !strcmp(prop->name, "status")) {  in of_reconfig_get_state_change()
138 		status_state = !strcmp(prop->value, "okay") ||  in of_reconfig_get_state_change()
139 			       !strcmp(prop->value, "ok");  in of_reconfig_get_state_change()
141 			old_status_state = !strcmp(old_prop->value, "okay") ||  in of_reconfig_get_state_change()
142 					   !strcmp(old_prop->value, "ok");  in of_reconfig_get_state_change()
148 		/* -1 & 0 status either missing or okay */  in of_reconfig_get_state_change()
152 		/* -1 & 0 status either missing or okay */  in of_reconfig_get_state_change()
158 			/* no status property -> enabled (legacy) */  in of_reconfig_get_state_change()
166 			/* no status property -> enabled (legacy) */  in of_reconfig_get_state_change()
186 		       struct property *prop, struct property *oldprop)  in of_property_notify()
190 	/* only call notifiers if the node is attached */  in of_property_notify()
209 		np->name = __of_get_property(np, "name", NULL);  in __of_attach_node()
210 		if (!np->name)  in __of_attach_node()
211 			np->name = "<NULL>";  in __of_attach_node()
219 			np->phandle = be32_to_cpup(phandle);  in __of_attach_node()
221 			np->phandle = 0;  in __of_attach_node()
224 	np->child = NULL;  in __of_attach_node()
225 	np->sibling = np->parent->child;  in __of_attach_node()
226 	np->parent->child = np;  in __of_attach_node()
228 	np->fwnode.flags |= FWNODE_FLAG_NOT_DEVICE;  in __of_attach_node()
236  * of_attach_node() - Plug a device node into the tree and global list.
237  * @np:		Pointer to the caller's Device Node
262 	parent = np->parent;  in __of_detach_node()
268 	if (parent->child == np)  in __of_detach_node()
269 		parent->child = np->sibling;  in __of_detach_node()
272 		for (prevsib = np->parent->child;  in __of_detach_node()
273 		     prevsib->sibling != np;  in __of_detach_node()
274 		     prevsib = prevsib->sibling)  in __of_detach_node()
276 		prevsib->sibling = np->sibling;  in __of_detach_node()
282 	__of_phandle_cache_inv_entry(np->phandle);  in __of_detach_node()
290  * of_detach_node() - "Unplug" a node from the device tree.
291  * @np:		Pointer to the caller's Device Node
310 void __of_prop_free(struct property *prop)  in __of_prop_free()
312 	kfree(prop->name);  in __of_prop_free()
313 	kfree(prop->value);  in __of_prop_free()
317 static void property_list_free(struct property *prop_list)  in property_list_free()
319 	struct property *prop, *next;  in property_list_free()
322 		next = prop->next;  in property_list_free()
328  * of_node_release() - release a dynamically allocated node
329  * @kobj: kernel object of the node to be released
335 	struct device_node *node = kobj_to_device_node(kobj);  in of_node_release()  local
338 	 * can not use '"%pOF", node' in pr_err() calls from this function  in of_node_release()
339 	 * because an of_node_get(node) when refcount is already zero  in of_node_release()
340 	 * will result in an error and a stack dump  in of_node_release()
344 	if (!of_node_check_flag(node, OF_DETACHED)) {  in of_node_release()
347 			__func__, node->parent, node->full_name);  in of_node_release()
352 		 * not display what a normal developer might reasonably  in of_node_release()
353 		 * consider a real bug.  in of_node_release()
356 		    strcmp(node->parent->full_name, "testcase-data")) {  in of_node_release()
358 …_err("ERROR: next of_node_put() on this node will result in a kobject warning 'refcount_t: underfl…  in of_node_release()
363 	if (!of_node_check_flag(node, OF_DYNAMIC))  in of_node_release()
366 	if (of_node_check_flag(node, OF_OVERLAY)) {  in of_node_release()
368 		if (!of_node_check_flag(node, OF_OVERLAY_FREE_CSET)) {  in of_node_release()
371 			       node);  in of_node_release()
376 		 * If node->properties non-empty then properties were added  in of_node_release()
377 		 * to this node either by different overlay that has not  in of_node_release()
378 		 * yet been removed, or by a non-overlay mechanism.  in of_node_release()
380 		if (node->properties)  in of_node_release()
382 			       __func__, node);  in of_node_release()
385 	if (node->child)  in of_node_release()
387 			__func__, node->parent, node->full_name);  in of_node_release()
389 	property_list_free(node->properties);  in of_node_release()
390 	property_list_free(node->deadprops);  in of_node_release()
391 	fwnode_links_purge(of_fwnode_handle(node));  in of_node_release()
393 	kfree(node->full_name);  in of_node_release()
394 	kfree(node->data);  in of_node_release()
395 	kfree(node);  in of_node_release()
399  * __of_prop_dup - Copy a property dynamically.
400  * @prop:	Property to copy
403  * Copy a property by dynamically allocating the memory of both the
404  * property structure and the property name & contents. The property's
408  * Return: The newly allocated property or NULL on out of memory error.
410 struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags)  in __of_prop_dup()
412 	struct property *new;  in __of_prop_dup()
420 	 * In case of a boolean property, this will allocate a value  in __of_prop_dup()
424 	new->name = kstrdup(prop->name, allocflags);  in __of_prop_dup()
425 	new->value = kmemdup(prop->value, prop->length, allocflags);  in __of_prop_dup()
426 	new->length = prop->length;  in __of_prop_dup()
427 	if (!new->name || !new->value)  in __of_prop_dup()
430 	/* mark the property as dynamic */  in __of_prop_dup()
441  * __of_node_dup() - Duplicate or create an empty device node dynamically.
442  * @np:		if not NULL, contains properties to be duplicated in new node
443  * @full_name:	string value to be duplicated into new node's full_name field
445  * Create a device tree node, optionally duplicating the properties of
446  * another node.  The node data are dynamically allocated and all the node
449  * Return: The newly allocated node or NULL on out of memory error.  Use
455 	struct device_node *node;  in __of_node_dup()  local
457 	node = kzalloc(sizeof(*node), GFP_KERNEL);  in __of_node_dup()
458 	if (!node)  in __of_node_dup()
460 	node->full_name = kstrdup(full_name, GFP_KERNEL);  in __of_node_dup()
461 	if (!node->full_name) {  in __of_node_dup()
462 		kfree(node);  in __of_node_dup()
466 	of_node_set_flag(node, OF_DYNAMIC);  in __of_node_dup()
467 	of_node_set_flag(node, OF_DETACHED);  in __of_node_dup()
468 	of_node_init(node);  in __of_node_dup()
472 		struct property *pp, *new_pp;  in __of_node_dup()
477 			if (__of_add_property(node, new_pp)) {  in __of_node_dup()
483 	return node;  in __of_node_dup()
486 	of_node_put(node); /* Frees the node and properties */  in __of_node_dup()
491  * of_changeset_create_node - Dynamically create a device node and attach to
492  * a given changeset.
495  * @parent: Pointer to parent device node
496  * @full_name: Node full name
498  * Return: Pointer to the created device node or NULL in case of an error.
510 	np->parent = parent;  in of_changeset_create_node()
524 	if (ce->action == OF_RECONFIG_ATTACH_NODE &&  in __of_changeset_entry_destroy()
525 	    of_node_check_flag(ce->np, OF_OVERLAY)) {  in __of_changeset_entry_destroy()
526 		if (kref_read(&ce->np->kobj.kref) > 1) {  in __of_changeset_entry_destroy()
527 …1 instead of %d, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node …  in __of_changeset_entry_destroy()
528 			       kref_read(&ce->np->kobj.kref), ce->np);  in __of_changeset_entry_destroy()
530 			of_node_set_flag(ce->np, OF_OVERLAY_FREE_CSET);  in __of_changeset_entry_destroy()
534 	of_node_put(ce->np);  in __of_changeset_entry_destroy()
535 	list_del(&ce->node);  in __of_changeset_entry_destroy()
544 	switch (ce->action) {  in __of_changeset_entry_invert()
546 		rce->action = OF_RECONFIG_DETACH_NODE;  in __of_changeset_entry_invert()
549 		rce->action = OF_RECONFIG_ATTACH_NODE;  in __of_changeset_entry_invert()
552 		rce->action = OF_RECONFIG_REMOVE_PROPERTY;  in __of_changeset_entry_invert()
555 		rce->action = OF_RECONFIG_ADD_PROPERTY;  in __of_changeset_entry_invert()
558 		rce->old_prop = ce->prop;  in __of_changeset_entry_invert()
559 		rce->prop = ce->old_prop;  in __of_changeset_entry_invert()
560 		/* update was used but original property did not exist */  in __of_changeset_entry_invert()
561 		if (!rce->prop) {  in __of_changeset_entry_invert()
562 			rce->action = OF_RECONFIG_REMOVE_PROPERTY;  in __of_changeset_entry_invert()
563 			rce->prop = ce->prop;  in __of_changeset_entry_invert()
581 	switch (ce->action) {  in __of_changeset_entry_notify()
585 		rd.dn = ce->np;  in __of_changeset_entry_notify()
586 		ret = of_reconfig_notify(ce->action, &rd);  in __of_changeset_entry_notify()
591 		ret = of_property_notify(ce->action, ce->np, ce->prop, ce->old_prop);  in __of_changeset_entry_notify()
595 			(int)ce->action);  in __of_changeset_entry_notify()
596 		ret = -EINVAL;  in __of_changeset_entry_notify()
600 		pr_err("changeset notifier error @%pOF\n", ce->np);  in __of_changeset_entry_notify()
608 	of_changeset_action_debug("apply: ", ce->action, ce->np, ce->prop);  in __of_changeset_entry_apply()
610 	switch (ce->action) {  in __of_changeset_entry_apply()
612 		__of_attach_node(ce->np);  in __of_changeset_entry_apply()
615 		__of_detach_node(ce->np);  in __of_changeset_entry_apply()
618 		ret = __of_add_property(ce->np, ce->prop);  in __of_changeset_entry_apply()
621 		ret = __of_remove_property(ce->np, ce->prop);  in __of_changeset_entry_apply()
625 		ret = __of_update_property(ce->np, ce->prop, &ce->old_prop);  in __of_changeset_entry_apply()
628 		ret = -EINVAL;  in __of_changeset_entry_apply()
632 		of_changeset_action_err("apply failed: ", ce->action, ce->np, ce->prop);  in __of_changeset_entry_apply()
648  * of_changeset_init - Initialize a changeset for use
652  * Initialize a changeset structure
657 	INIT_LIST_HEAD(&ocs->entries);  in of_changeset_init()
662  * of_changeset_destroy - Destroy a changeset
666  * Destroys a changeset. Note that if a changeset is applied,
674 	 * When a device is deleted, the device links to/from it are also queued  in of_changeset_destroy()
677 	 * overlay change, this device might be holding a reference to a device  in of_changeset_destroy()
678 	 * node that will be freed. So, wait until all already pending device  in of_changeset_destroy()
679 	 * links are deleted before freeing a device node. This ensures we don't  in of_changeset_destroy()
680 	 * free any device node that has a non-zero reference count.  in of_changeset_destroy()
684 	list_for_each_entry_safe_reverse(ce, cen, &ocs->entries, node)  in of_changeset_destroy()
696  * Returns 0 on success, a negative error value in case of an error.
697  * If a revert error occurs, it is returned in *ret_revert.
705 	list_for_each_entry(ce, &ocs->entries, node) {  in __of_changeset_apply_entries()
709 			list_for_each_entry_continue_reverse(ce, &ocs->entries,  in __of_changeset_apply_entries()
710 							     node) {  in __of_changeset_apply_entries()
723  * Returns 0 on success, a negative error value in case of an error.
737 	list_for_each_entry(ce, &ocs->entries, node) {  in __of_changeset_apply_notify()
749  * Returns 0 on success, a negative error value in case of an error.
751  * If a changeset entry apply fails, an attempt is made to revert any
768  * of_changeset_apply - Applies a changeset
772  * Applies a changeset to the live tree.
773  * Any side-effects of live tree state changes are applied here on
774  * success, like creation/destruction of devices and side-effects
777  * Return: 0 on success, a negative error value in case of an error.
794  * If revert fails, an attempt is made to re-apply the entries that were
797  * If multiple re-apply errors occur then only the final apply error is
800  * Returns 0 on success, a negative error value in case of an error.
809 	list_for_each_entry_reverse(ce, &ocs->entries, node) {  in __of_changeset_revert_entries()
813 			list_for_each_entry_continue(ce, &ocs->entries, node) {  in __of_changeset_revert_entries()
838 	list_for_each_entry_reverse(ce, &ocs->entries, node) {  in __of_changeset_revert_notify()
863  * of_changeset_revert - Reverts an applied changeset
867  * Reverts a changeset returning the state of the tree to what it
869  * Any side-effects like creation/destruction of devices and
872  * Return: 0 on success, a negative error value in case of an error.
887  * of_changeset_action - Add an action to the tail of the changeset list
891  * @np:		Pointer to device node
892  * @prop:	Pointer to property
901  * Return: 0 on success, a negative error value in case of an error.
904 		struct device_node *np, struct property *prop)  in of_changeset_action()
909 		return -EINVAL;  in of_changeset_action()
913 		return -ENOMEM;  in of_changeset_action()
915 	/* get a reference to the node */  in of_changeset_action()
916 	ce->action = action;  in of_changeset_action()
917 	ce->np = of_node_get(np);  in of_changeset_action()
918 	ce->prop = prop;  in of_changeset_action()
921 	list_add_tail(&ce->node, &ocs->entries);  in of_changeset_action()
928 					const struct property *pp)  in of_changeset_add_prop_helper()
930 	struct property *new_pp;  in of_changeset_add_prop_helper()
935 		return -ENOMEM;  in of_changeset_add_prop_helper()
945  * of_changeset_add_prop_string - Add a string property to a changeset
948  * @np:		device node pointer
949  * @prop_name:	name of the property to be added
952  * Create a string property and add it to a changeset.
954  * Return: 0 on success, a negative error value in case of an error.
960 	struct property prop;  in of_changeset_add_prop_string()
971  * of_changeset_add_prop_string_array - Add a string list property to
972  * a changeset
975  * @np:		device node pointer
976  * @prop_name:	name of the property to be added
980  * Create a string list property and add it to a changeset.
982  * Return: 0 on success, a negative error value in case of an error.
989 	struct property prop;  in of_changeset_add_prop_string_array()
1001 		return -ENOMEM;  in of_changeset_add_prop_string_array()
1005 		vp += snprintf(vp, (char *)prop.value + prop.length - vp, "%s",  in of_changeset_add_prop_string_array()
1016  * of_changeset_add_prop_u32_array - Add a property of 32 bit integers
1017  * property to a changeset
1020  * @np:		device node pointer
1021  * @prop_name:	name of the property to be added
1025  * Create a property of 32 bit integers and add it to a changeset.
1027  * Return: 0 on success, a negative error value in case of an error.
1034 	struct property prop;  in of_changeset_add_prop_u32_array()
1039 		return -ENOMEM;  in of_changeset_add_prop_u32_array()
1052  * of_changeset_add_prop_bool - Add a boolean property (i.e. a property without
1053  * any values) to a changeset.
1056  * @np:		device node pointer
1057  * @prop_name:	name of the property to be added
1059  * Create a boolean property and add it to a changeset.
1061  * Return: 0 on success, a negative error value in case of an error.
1066 	struct property prop;  in of_changeset_add_prop_bool()
1078 					   const struct property *pp)  in of_changeset_update_prop_helper()
1080 	struct property *new_pp;  in of_changeset_update_prop_helper()
1085 		return -ENOMEM;  in of_changeset_update_prop_helper()
1095  * of_changeset_update_prop_string - Add a string property update to a changeset
1098  * @np:		device node pointer
1099  * @prop_name:	name of the property to be updated
1102  * Create a string property to be updated and add it to a changeset.
1104  * Return: 0 on success, a negative error value in case of an error.
1110 	struct property prop = {  in of_changeset_update_prop_string()