xref: /linux-6.15/include/linux/of.h (revision c2e7075c)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 #ifndef _LINUX_OF_H
3 #define _LINUX_OF_H
4 /*
5  * Definitions for talking to the Open Firmware PROM on
6  * Power Macintosh and other computers.
7  *
8  * Copyright (C) 1996-2005 Paul Mackerras.
9  *
10  * Updates for PPC64 by Peter Bergner & David Engebretsen, IBM Corp.
11  * Updates for SPARC64 by David S. Miller
12  * Derived from PowerPC and Sparc prom.h files by Stephen Rothwell, IBM Corp.
13  */
14 #include <linux/types.h>
15 #include <linux/bitops.h>
16 #include <linux/errno.h>
17 #include <linux/kobject.h>
18 #include <linux/mod_devicetable.h>
19 #include <linux/spinlock.h>
20 #include <linux/topology.h>
21 #include <linux/notifier.h>
22 #include <linux/property.h>
23 #include <linux/list.h>
24 
25 #include <asm/byteorder.h>
26 #include <asm/errno.h>
27 
28 typedef u32 phandle;
29 typedef u32 ihandle;
30 
31 struct property {
32 	char	*name;
33 	int	length;
34 	void	*value;
35 	struct property *next;
36 #if defined(CONFIG_OF_DYNAMIC) || defined(CONFIG_SPARC)
37 	unsigned long _flags;
38 #endif
39 #if defined(CONFIG_OF_PROMTREE)
40 	unsigned int unique_id;
41 #endif
42 #if defined(CONFIG_OF_KOBJ)
43 	struct bin_attribute attr;
44 #endif
45 };
46 
47 #if defined(CONFIG_SPARC)
48 struct of_irq_controller;
49 #endif
50 
51 struct device_node {
52 	const char *name;
53 	const char *type;
54 	phandle phandle;
55 	const char *full_name;
56 	struct fwnode_handle fwnode;
57 
58 	struct	property *properties;
59 	struct	property *deadprops;	/* removed properties */
60 	struct	device_node *parent;
61 	struct	device_node *child;
62 	struct	device_node *sibling;
63 #if defined(CONFIG_OF_KOBJ)
64 	struct	kobject kobj;
65 #endif
66 	unsigned long _flags;
67 	void	*data;
68 #if defined(CONFIG_SPARC)
69 	const char *path_component_name;
70 	unsigned int unique_id;
71 	struct of_irq_controller *irq_trans;
72 #endif
73 };
74 
75 #define MAX_PHANDLE_ARGS 16
76 struct of_phandle_args {
77 	struct device_node *np;
78 	int args_count;
79 	uint32_t args[MAX_PHANDLE_ARGS];
80 };
81 
82 struct of_phandle_iterator {
83 	/* Common iterator information */
84 	const char *cells_name;
85 	int cell_count;
86 	const struct device_node *parent;
87 
88 	/* List size information */
89 	const __be32 *list_end;
90 	const __be32 *phandle_end;
91 
92 	/* Current position state */
93 	const __be32 *cur;
94 	uint32_t cur_count;
95 	phandle phandle;
96 	struct device_node *node;
97 };
98 
99 struct of_reconfig_data {
100 	struct device_node	*dn;
101 	struct property		*prop;
102 	struct property		*old_prop;
103 };
104 
105 /* initialize a node */
106 extern struct kobj_type of_node_ktype;
107 extern const struct fwnode_operations of_fwnode_ops;
108 static inline void of_node_init(struct device_node *node)
109 {
110 #if defined(CONFIG_OF_KOBJ)
111 	kobject_init(&node->kobj, &of_node_ktype);
112 #endif
113 	node->fwnode.ops = &of_fwnode_ops;
114 }
115 
116 #if defined(CONFIG_OF_KOBJ)
117 #define of_node_kobj(n) (&(n)->kobj)
118 #else
119 #define of_node_kobj(n) NULL
120 #endif
121 
122 #ifdef CONFIG_OF_DYNAMIC
123 extern struct device_node *of_node_get(struct device_node *node);
124 extern void of_node_put(struct device_node *node);
125 #else /* CONFIG_OF_DYNAMIC */
126 /* Dummy ref counting routines - to be implemented later */
127 static inline struct device_node *of_node_get(struct device_node *node)
128 {
129 	return node;
130 }
131 static inline void of_node_put(struct device_node *node) { }
132 #endif /* !CONFIG_OF_DYNAMIC */
133 
134 /* Pointer for first entry in chain of all nodes. */
135 extern struct device_node *of_root;
136 extern struct device_node *of_chosen;
137 extern struct device_node *of_aliases;
138 extern struct device_node *of_stdout;
139 extern raw_spinlock_t devtree_lock;
140 
141 /*
142  * struct device_node flag descriptions
143  * (need to be visible even when !CONFIG_OF)
144  */
145 #define OF_DYNAMIC		1 /* (and properties) allocated via kmalloc */
146 #define OF_DETACHED		2 /* detached from the device tree */
147 #define OF_POPULATED		3 /* device already created */
148 #define OF_POPULATED_BUS	4 /* platform bus created for children */
149 #define OF_OVERLAY		5 /* allocated for an overlay */
150 #define OF_OVERLAY_FREE_CSET	6 /* in overlay cset being freed */
151 
152 #define OF_BAD_ADDR	((u64)-1)
153 
154 #ifdef CONFIG_OF
155 void of_core_init(void);
156 
157 static inline bool is_of_node(const struct fwnode_handle *fwnode)
158 {
159 	return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &of_fwnode_ops;
160 }
161 
162 #define to_of_node(__fwnode)						\
163 	({								\
164 		typeof(__fwnode) __to_of_node_fwnode = (__fwnode);	\
165 									\
166 		is_of_node(__to_of_node_fwnode) ?			\
167 			container_of(__to_of_node_fwnode,		\
168 				     struct device_node, fwnode) :	\
169 			NULL;						\
170 	})
171 
172 #define of_fwnode_handle(node)						\
173 	({								\
174 		typeof(node) __of_fwnode_handle_node = (node);		\
175 									\
176 		__of_fwnode_handle_node ?				\
177 			&__of_fwnode_handle_node->fwnode : NULL;	\
178 	})
179 
180 static inline bool of_have_populated_dt(void)
181 {
182 	return of_root != NULL;
183 }
184 
185 static inline bool of_node_is_root(const struct device_node *node)
186 {
187 	return node && (node->parent == NULL);
188 }
189 
190 static inline int of_node_check_flag(struct device_node *n, unsigned long flag)
191 {
192 	return test_bit(flag, &n->_flags);
193 }
194 
195 static inline int of_node_test_and_set_flag(struct device_node *n,
196 					    unsigned long flag)
197 {
198 	return test_and_set_bit(flag, &n->_flags);
199 }
200 
201 static inline void of_node_set_flag(struct device_node *n, unsigned long flag)
202 {
203 	set_bit(flag, &n->_flags);
204 }
205 
206 static inline void of_node_clear_flag(struct device_node *n, unsigned long flag)
207 {
208 	clear_bit(flag, &n->_flags);
209 }
210 
211 #if defined(CONFIG_OF_DYNAMIC) || defined(CONFIG_SPARC)
212 static inline int of_property_check_flag(struct property *p, unsigned long flag)
213 {
214 	return test_bit(flag, &p->_flags);
215 }
216 
217 static inline void of_property_set_flag(struct property *p, unsigned long flag)
218 {
219 	set_bit(flag, &p->_flags);
220 }
221 
222 static inline void of_property_clear_flag(struct property *p, unsigned long flag)
223 {
224 	clear_bit(flag, &p->_flags);
225 }
226 #endif
227 
228 extern struct device_node *__of_find_all_nodes(struct device_node *prev);
229 extern struct device_node *of_find_all_nodes(struct device_node *prev);
230 
231 /*
232  * OF address retrieval & translation
233  */
234 
235 /* Helper to read a big number; size is in cells (not bytes) */
236 static inline u64 of_read_number(const __be32 *cell, int size)
237 {
238 	u64 r = 0;
239 	while (size--)
240 		r = (r << 32) | be32_to_cpu(*(cell++));
241 	return r;
242 }
243 
244 /* Like of_read_number, but we want an unsigned long result */
245 static inline unsigned long of_read_ulong(const __be32 *cell, int size)
246 {
247 	/* toss away upper bits if unsigned long is smaller than u64 */
248 	return of_read_number(cell, size);
249 }
250 
251 #if defined(CONFIG_SPARC)
252 #include <asm/prom.h>
253 #endif
254 
255 #define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags)
256 #define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags)
257 
258 extern bool of_node_name_eq(const struct device_node *np, const char *name);
259 extern bool of_node_name_prefix(const struct device_node *np, const char *prefix);
260 
261 static inline const char *of_node_full_name(const struct device_node *np)
262 {
263 	return np ? np->full_name : "<no-node>";
264 }
265 
266 #define for_each_of_allnodes_from(from, dn) \
267 	for (dn = __of_find_all_nodes(from); dn; dn = __of_find_all_nodes(dn))
268 #define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn)
269 extern struct device_node *of_find_node_by_name(struct device_node *from,
270 	const char *name);
271 extern struct device_node *of_find_node_by_type(struct device_node *from,
272 	const char *type);
273 extern struct device_node *of_find_compatible_node(struct device_node *from,
274 	const char *type, const char *compat);
275 extern struct device_node *of_find_matching_node_and_match(
276 	struct device_node *from,
277 	const struct of_device_id *matches,
278 	const struct of_device_id **match);
279 
280 extern struct device_node *of_find_node_opts_by_path(const char *path,
281 	const char **opts);
282 static inline struct device_node *of_find_node_by_path(const char *path)
283 {
284 	return of_find_node_opts_by_path(path, NULL);
285 }
286 
287 extern struct device_node *of_find_node_by_phandle(phandle handle);
288 extern struct device_node *of_get_parent(const struct device_node *node);
289 extern struct device_node *of_get_next_parent(struct device_node *node);
290 extern struct device_node *of_get_next_child(const struct device_node *node,
291 					     struct device_node *prev);
292 extern struct device_node *of_get_next_available_child(
293 	const struct device_node *node, struct device_node *prev);
294 
295 extern struct device_node *of_get_compatible_child(const struct device_node *parent,
296 					const char *compatible);
297 extern struct device_node *of_get_child_by_name(const struct device_node *node,
298 					const char *name);
299 
300 /* cache lookup */
301 extern struct device_node *of_find_next_cache_node(const struct device_node *);
302 extern int of_find_last_cache_level(unsigned int cpu);
303 extern struct device_node *of_find_node_with_property(
304 	struct device_node *from, const char *prop_name);
305 
306 extern struct property *of_find_property(const struct device_node *np,
307 					 const char *name,
308 					 int *lenp);
309 extern int of_property_count_elems_of_size(const struct device_node *np,
310 				const char *propname, int elem_size);
311 extern int of_property_read_u32_index(const struct device_node *np,
312 				       const char *propname,
313 				       u32 index, u32 *out_value);
314 extern int of_property_read_u64_index(const struct device_node *np,
315 				       const char *propname,
316 				       u32 index, u64 *out_value);
317 extern int of_property_read_variable_u8_array(const struct device_node *np,
318 					const char *propname, u8 *out_values,
319 					size_t sz_min, size_t sz_max);
320 extern int of_property_read_variable_u16_array(const struct device_node *np,
321 					const char *propname, u16 *out_values,
322 					size_t sz_min, size_t sz_max);
323 extern int of_property_read_variable_u32_array(const struct device_node *np,
324 					const char *propname,
325 					u32 *out_values,
326 					size_t sz_min,
327 					size_t sz_max);
328 extern int of_property_read_u64(const struct device_node *np,
329 				const char *propname, u64 *out_value);
330 extern int of_property_read_variable_u64_array(const struct device_node *np,
331 					const char *propname,
332 					u64 *out_values,
333 					size_t sz_min,
334 					size_t sz_max);
335 
336 extern int of_property_read_string(const struct device_node *np,
337 				   const char *propname,
338 				   const char **out_string);
339 extern int of_property_match_string(const struct device_node *np,
340 				    const char *propname,
341 				    const char *string);
342 extern int of_property_read_string_helper(const struct device_node *np,
343 					      const char *propname,
344 					      const char **out_strs, size_t sz, int index);
345 extern int of_device_is_compatible(const struct device_node *device,
346 				   const char *);
347 extern int of_device_compatible_match(struct device_node *device,
348 				      const char *const *compat);
349 extern bool of_device_is_available(const struct device_node *device);
350 extern bool of_device_is_big_endian(const struct device_node *device);
351 extern const void *of_get_property(const struct device_node *node,
352 				const char *name,
353 				int *lenp);
354 extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread);
355 extern struct device_node *of_get_next_cpu_node(struct device_node *prev);
356 
357 #define for_each_property_of_node(dn, pp) \
358 	for (pp = dn->properties; pp != NULL; pp = pp->next)
359 
360 extern int of_n_addr_cells(struct device_node *np);
361 extern int of_n_size_cells(struct device_node *np);
362 extern const struct of_device_id *of_match_node(
363 	const struct of_device_id *matches, const struct device_node *node);
364 extern int of_modalias_node(struct device_node *node, char *modalias, int len);
365 extern void of_print_phandle_args(const char *msg, const struct of_phandle_args *args);
366 extern struct device_node *of_parse_phandle(const struct device_node *np,
367 					    const char *phandle_name,
368 					    int index);
369 extern int of_parse_phandle_with_args(const struct device_node *np,
370 	const char *list_name, const char *cells_name, int index,
371 	struct of_phandle_args *out_args);
372 extern int of_parse_phandle_with_args_map(const struct device_node *np,
373 	const char *list_name, const char *stem_name, int index,
374 	struct of_phandle_args *out_args);
375 extern int of_parse_phandle_with_fixed_args(const struct device_node *np,
376 	const char *list_name, int cells_count, int index,
377 	struct of_phandle_args *out_args);
378 extern int of_count_phandle_with_args(const struct device_node *np,
379 	const char *list_name, const char *cells_name);
380 
381 /* phandle iterator functions */
382 extern int of_phandle_iterator_init(struct of_phandle_iterator *it,
383 				    const struct device_node *np,
384 				    const char *list_name,
385 				    const char *cells_name,
386 				    int cell_count);
387 
388 extern int of_phandle_iterator_next(struct of_phandle_iterator *it);
389 extern int of_phandle_iterator_args(struct of_phandle_iterator *it,
390 				    uint32_t *args,
391 				    int size);
392 
393 extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align));
394 extern int of_alias_get_id(struct device_node *np, const char *stem);
395 extern int of_alias_get_highest_id(const char *stem);
396 extern int of_alias_get_alias_list(const struct of_device_id *matches,
397 				   const char *stem, unsigned long *bitmap,
398 				   unsigned int nbits);
399 
400 extern int of_machine_is_compatible(const char *compat);
401 
402 extern int of_add_property(struct device_node *np, struct property *prop);
403 extern int of_remove_property(struct device_node *np, struct property *prop);
404 extern int of_update_property(struct device_node *np, struct property *newprop);
405 
406 /* For updating the device tree at runtime */
407 #define OF_RECONFIG_ATTACH_NODE		0x0001
408 #define OF_RECONFIG_DETACH_NODE		0x0002
409 #define OF_RECONFIG_ADD_PROPERTY	0x0003
410 #define OF_RECONFIG_REMOVE_PROPERTY	0x0004
411 #define OF_RECONFIG_UPDATE_PROPERTY	0x0005
412 
413 extern int of_attach_node(struct device_node *);
414 extern int of_detach_node(struct device_node *);
415 
416 #define of_match_ptr(_ptr)	(_ptr)
417 
418 /**
419  * of_property_read_u8_array - Find and read an array of u8 from a property.
420  *
421  * @np:		device node from which the property value is to be read.
422  * @propname:	name of the property to be searched.
423  * @out_values:	pointer to return value, modified only if return value is 0.
424  * @sz:		number of array elements to read
425  *
426  * Search for a property in a device node and read 8-bit value(s) from
427  * it. Returns 0 on success, -EINVAL if the property does not exist,
428  * -ENODATA if property does not have a value, and -EOVERFLOW if the
429  * property data isn't large enough.
430  *
431  * dts entry of array should be like:
432  *	property = /bits/ 8 <0x50 0x60 0x70>;
433  *
434  * The out_values is modified only if a valid u8 value can be decoded.
435  */
436 static inline int of_property_read_u8_array(const struct device_node *np,
437 					    const char *propname,
438 					    u8 *out_values, size_t sz)
439 {
440 	int ret = of_property_read_variable_u8_array(np, propname, out_values,
441 						     sz, 0);
442 	if (ret >= 0)
443 		return 0;
444 	else
445 		return ret;
446 }
447 
448 /**
449  * of_property_read_u16_array - Find and read an array of u16 from a property.
450  *
451  * @np:		device node from which the property value is to be read.
452  * @propname:	name of the property to be searched.
453  * @out_values:	pointer to return value, modified only if return value is 0.
454  * @sz:		number of array elements to read
455  *
456  * Search for a property in a device node and read 16-bit value(s) from
457  * it. Returns 0 on success, -EINVAL if the property does not exist,
458  * -ENODATA if property does not have a value, and -EOVERFLOW if the
459  * property data isn't large enough.
460  *
461  * dts entry of array should be like:
462  *	property = /bits/ 16 <0x5000 0x6000 0x7000>;
463  *
464  * The out_values is modified only if a valid u16 value can be decoded.
465  */
466 static inline int of_property_read_u16_array(const struct device_node *np,
467 					     const char *propname,
468 					     u16 *out_values, size_t sz)
469 {
470 	int ret = of_property_read_variable_u16_array(np, propname, out_values,
471 						      sz, 0);
472 	if (ret >= 0)
473 		return 0;
474 	else
475 		return ret;
476 }
477 
478 /**
479  * of_property_read_u32_array - Find and read an array of 32 bit integers
480  * from a property.
481  *
482  * @np:		device node from which the property value is to be read.
483  * @propname:	name of the property to be searched.
484  * @out_values:	pointer to return value, modified only if return value is 0.
485  * @sz:		number of array elements to read
486  *
487  * Search for a property in a device node and read 32-bit value(s) from
488  * it. Returns 0 on success, -EINVAL if the property does not exist,
489  * -ENODATA if property does not have a value, and -EOVERFLOW if the
490  * property data isn't large enough.
491  *
492  * The out_values is modified only if a valid u32 value can be decoded.
493  */
494 static inline int of_property_read_u32_array(const struct device_node *np,
495 					     const char *propname,
496 					     u32 *out_values, size_t sz)
497 {
498 	int ret = of_property_read_variable_u32_array(np, propname, out_values,
499 						      sz, 0);
500 	if (ret >= 0)
501 		return 0;
502 	else
503 		return ret;
504 }
505 
506 /**
507  * of_property_read_u64_array - Find and read an array of 64 bit integers
508  * from a property.
509  *
510  * @np:		device node from which the property value is to be read.
511  * @propname:	name of the property to be searched.
512  * @out_values:	pointer to return value, modified only if return value is 0.
513  * @sz:		number of array elements to read
514  *
515  * Search for a property in a device node and read 64-bit value(s) from
516  * it. Returns 0 on success, -EINVAL if the property does not exist,
517  * -ENODATA if property does not have a value, and -EOVERFLOW if the
518  * property data isn't large enough.
519  *
520  * The out_values is modified only if a valid u64 value can be decoded.
521  */
522 static inline int of_property_read_u64_array(const struct device_node *np,
523 					     const char *propname,
524 					     u64 *out_values, size_t sz)
525 {
526 	int ret = of_property_read_variable_u64_array(np, propname, out_values,
527 						      sz, 0);
528 	if (ret >= 0)
529 		return 0;
530 	else
531 		return ret;
532 }
533 
534 /*
535  * struct property *prop;
536  * const __be32 *p;
537  * u32 u;
538  *
539  * of_property_for_each_u32(np, "propname", prop, p, u)
540  *         printk("U32 value: %x\n", u);
541  */
542 const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
543 			       u32 *pu);
544 /*
545  * struct property *prop;
546  * const char *s;
547  *
548  * of_property_for_each_string(np, "propname", prop, s)
549  *         printk("String value: %s\n", s);
550  */
551 const char *of_prop_next_string(struct property *prop, const char *cur);
552 
553 bool of_console_check(struct device_node *dn, char *name, int index);
554 
555 extern int of_cpu_node_to_id(struct device_node *np);
556 
557 int of_map_rid(struct device_node *np, u32 rid,
558 	       const char *map_name, const char *map_mask_name,
559 	       struct device_node **target, u32 *id_out);
560 
561 #else /* CONFIG_OF */
562 
563 static inline void of_core_init(void)
564 {
565 }
566 
567 static inline bool is_of_node(const struct fwnode_handle *fwnode)
568 {
569 	return false;
570 }
571 
572 static inline struct device_node *to_of_node(const struct fwnode_handle *fwnode)
573 {
574 	return NULL;
575 }
576 
577 static inline bool of_node_name_eq(const struct device_node *np, const char *name)
578 {
579 	return false;
580 }
581 
582 static inline bool of_node_name_prefix(const struct device_node *np, const char *prefix)
583 {
584 	return false;
585 }
586 
587 static inline const char* of_node_full_name(const struct device_node *np)
588 {
589 	return "<no-node>";
590 }
591 
592 static inline struct device_node *of_find_node_by_name(struct device_node *from,
593 	const char *name)
594 {
595 	return NULL;
596 }
597 
598 static inline struct device_node *of_find_node_by_type(struct device_node *from,
599 	const char *type)
600 {
601 	return NULL;
602 }
603 
604 static inline struct device_node *of_find_matching_node_and_match(
605 	struct device_node *from,
606 	const struct of_device_id *matches,
607 	const struct of_device_id **match)
608 {
609 	return NULL;
610 }
611 
612 static inline struct device_node *of_find_node_by_path(const char *path)
613 {
614 	return NULL;
615 }
616 
617 static inline struct device_node *of_find_node_opts_by_path(const char *path,
618 	const char **opts)
619 {
620 	return NULL;
621 }
622 
623 static inline struct device_node *of_find_node_by_phandle(phandle handle)
624 {
625 	return NULL;
626 }
627 
628 static inline struct device_node *of_get_parent(const struct device_node *node)
629 {
630 	return NULL;
631 }
632 
633 static inline struct device_node *of_get_next_child(
634 	const struct device_node *node, struct device_node *prev)
635 {
636 	return NULL;
637 }
638 
639 static inline struct device_node *of_get_next_available_child(
640 	const struct device_node *node, struct device_node *prev)
641 {
642 	return NULL;
643 }
644 
645 static inline struct device_node *of_find_node_with_property(
646 	struct device_node *from, const char *prop_name)
647 {
648 	return NULL;
649 }
650 
651 #define of_fwnode_handle(node) NULL
652 
653 static inline bool of_have_populated_dt(void)
654 {
655 	return false;
656 }
657 
658 static inline struct device_node *of_get_compatible_child(const struct device_node *parent,
659 					const char *compatible)
660 {
661 	return NULL;
662 }
663 
664 static inline struct device_node *of_get_child_by_name(
665 					const struct device_node *node,
666 					const char *name)
667 {
668 	return NULL;
669 }
670 
671 static inline int of_device_is_compatible(const struct device_node *device,
672 					  const char *name)
673 {
674 	return 0;
675 }
676 
677 static inline  int of_device_compatible_match(struct device_node *device,
678 					      const char *const *compat)
679 {
680 	return 0;
681 }
682 
683 static inline bool of_device_is_available(const struct device_node *device)
684 {
685 	return false;
686 }
687 
688 static inline bool of_device_is_big_endian(const struct device_node *device)
689 {
690 	return false;
691 }
692 
693 static inline struct property *of_find_property(const struct device_node *np,
694 						const char *name,
695 						int *lenp)
696 {
697 	return NULL;
698 }
699 
700 static inline struct device_node *of_find_compatible_node(
701 						struct device_node *from,
702 						const char *type,
703 						const char *compat)
704 {
705 	return NULL;
706 }
707 
708 static inline int of_property_count_elems_of_size(const struct device_node *np,
709 			const char *propname, int elem_size)
710 {
711 	return -ENOSYS;
712 }
713 
714 static inline int of_property_read_u8_array(const struct device_node *np,
715 			const char *propname, u8 *out_values, size_t sz)
716 {
717 	return -ENOSYS;
718 }
719 
720 static inline int of_property_read_u16_array(const struct device_node *np,
721 			const char *propname, u16 *out_values, size_t sz)
722 {
723 	return -ENOSYS;
724 }
725 
726 static inline int of_property_read_u32_array(const struct device_node *np,
727 					     const char *propname,
728 					     u32 *out_values, size_t sz)
729 {
730 	return -ENOSYS;
731 }
732 
733 static inline int of_property_read_u64_array(const struct device_node *np,
734 					     const char *propname,
735 					     u64 *out_values, size_t sz)
736 {
737 	return -ENOSYS;
738 }
739 
740 static inline int of_property_read_u32_index(const struct device_node *np,
741 			const char *propname, u32 index, u32 *out_value)
742 {
743 	return -ENOSYS;
744 }
745 
746 static inline int of_property_read_u64_index(const struct device_node *np,
747 			const char *propname, u32 index, u64 *out_value)
748 {
749 	return -ENOSYS;
750 }
751 
752 static inline const void *of_get_property(const struct device_node *node,
753 				const char *name,
754 				int *lenp)
755 {
756 	return NULL;
757 }
758 
759 static inline struct device_node *of_get_cpu_node(int cpu,
760 					unsigned int *thread)
761 {
762 	return NULL;
763 }
764 
765 static inline struct device_node *of_get_next_cpu_node(struct device_node *prev)
766 {
767 	return NULL;
768 }
769 
770 static inline int of_n_addr_cells(struct device_node *np)
771 {
772 	return 0;
773 
774 }
775 static inline int of_n_size_cells(struct device_node *np)
776 {
777 	return 0;
778 }
779 
780 static inline int of_property_read_variable_u8_array(const struct device_node *np,
781 					const char *propname, u8 *out_values,
782 					size_t sz_min, size_t sz_max)
783 {
784 	return -ENOSYS;
785 }
786 
787 static inline int of_property_read_variable_u16_array(const struct device_node *np,
788 					const char *propname, u16 *out_values,
789 					size_t sz_min, size_t sz_max)
790 {
791 	return -ENOSYS;
792 }
793 
794 static inline int of_property_read_variable_u32_array(const struct device_node *np,
795 					const char *propname,
796 					u32 *out_values,
797 					size_t sz_min,
798 					size_t sz_max)
799 {
800 	return -ENOSYS;
801 }
802 
803 static inline int of_property_read_u64(const struct device_node *np,
804 				       const char *propname, u64 *out_value)
805 {
806 	return -ENOSYS;
807 }
808 
809 static inline int of_property_read_variable_u64_array(const struct device_node *np,
810 					const char *propname,
811 					u64 *out_values,
812 					size_t sz_min,
813 					size_t sz_max)
814 {
815 	return -ENOSYS;
816 }
817 
818 static inline int of_property_read_string(const struct device_node *np,
819 					  const char *propname,
820 					  const char **out_string)
821 {
822 	return -ENOSYS;
823 }
824 
825 static inline int of_property_match_string(const struct device_node *np,
826 					   const char *propname,
827 					   const char *string)
828 {
829 	return -ENOSYS;
830 }
831 
832 static inline int of_property_read_string_helper(const struct device_node *np,
833 						 const char *propname,
834 						 const char **out_strs, size_t sz, int index)
835 {
836 	return -ENOSYS;
837 }
838 
839 static inline struct device_node *of_parse_phandle(const struct device_node *np,
840 						   const char *phandle_name,
841 						   int index)
842 {
843 	return NULL;
844 }
845 
846 static inline int of_parse_phandle_with_args(const struct device_node *np,
847 					     const char *list_name,
848 					     const char *cells_name,
849 					     int index,
850 					     struct of_phandle_args *out_args)
851 {
852 	return -ENOSYS;
853 }
854 
855 static inline int of_parse_phandle_with_args_map(const struct device_node *np,
856 						 const char *list_name,
857 						 const char *stem_name,
858 						 int index,
859 						 struct of_phandle_args *out_args)
860 {
861 	return -ENOSYS;
862 }
863 
864 static inline int of_parse_phandle_with_fixed_args(const struct device_node *np,
865 	const char *list_name, int cells_count, int index,
866 	struct of_phandle_args *out_args)
867 {
868 	return -ENOSYS;
869 }
870 
871 static inline int of_count_phandle_with_args(struct device_node *np,
872 					     const char *list_name,
873 					     const char *cells_name)
874 {
875 	return -ENOSYS;
876 }
877 
878 static inline int of_phandle_iterator_init(struct of_phandle_iterator *it,
879 					   const struct device_node *np,
880 					   const char *list_name,
881 					   const char *cells_name,
882 					   int cell_count)
883 {
884 	return -ENOSYS;
885 }
886 
887 static inline int of_phandle_iterator_next(struct of_phandle_iterator *it)
888 {
889 	return -ENOSYS;
890 }
891 
892 static inline int of_phandle_iterator_args(struct of_phandle_iterator *it,
893 					   uint32_t *args,
894 					   int size)
895 {
896 	return 0;
897 }
898 
899 static inline int of_alias_get_id(struct device_node *np, const char *stem)
900 {
901 	return -ENOSYS;
902 }
903 
904 static inline int of_alias_get_highest_id(const char *stem)
905 {
906 	return -ENOSYS;
907 }
908 
909 static inline int of_alias_get_alias_list(const struct of_device_id *matches,
910 					  const char *stem, unsigned long *bitmap,
911 					  unsigned int nbits)
912 {
913 	return -ENOSYS;
914 }
915 
916 static inline int of_machine_is_compatible(const char *compat)
917 {
918 	return 0;
919 }
920 
921 static inline bool of_console_check(const struct device_node *dn, const char *name, int index)
922 {
923 	return false;
924 }
925 
926 static inline const __be32 *of_prop_next_u32(struct property *prop,
927 		const __be32 *cur, u32 *pu)
928 {
929 	return NULL;
930 }
931 
932 static inline const char *of_prop_next_string(struct property *prop,
933 		const char *cur)
934 {
935 	return NULL;
936 }
937 
938 static inline int of_node_check_flag(struct device_node *n, unsigned long flag)
939 {
940 	return 0;
941 }
942 
943 static inline int of_node_test_and_set_flag(struct device_node *n,
944 					    unsigned long flag)
945 {
946 	return 0;
947 }
948 
949 static inline void of_node_set_flag(struct device_node *n, unsigned long flag)
950 {
951 }
952 
953 static inline void of_node_clear_flag(struct device_node *n, unsigned long flag)
954 {
955 }
956 
957 static inline int of_property_check_flag(struct property *p, unsigned long flag)
958 {
959 	return 0;
960 }
961 
962 static inline void of_property_set_flag(struct property *p, unsigned long flag)
963 {
964 }
965 
966 static inline void of_property_clear_flag(struct property *p, unsigned long flag)
967 {
968 }
969 
970 static inline int of_cpu_node_to_id(struct device_node *np)
971 {
972 	return -ENODEV;
973 }
974 
975 static inline int of_map_rid(struct device_node *np, u32 rid,
976 			     const char *map_name, const char *map_mask_name,
977 			     struct device_node **target, u32 *id_out)
978 {
979 	return -EINVAL;
980 }
981 
982 #define of_match_ptr(_ptr)	NULL
983 #define of_match_node(_matches, _node)	NULL
984 #endif /* CONFIG_OF */
985 
986 /* Default string compare functions, Allow arch asm/prom.h to override */
987 #if !defined(of_compat_cmp)
988 #define of_compat_cmp(s1, s2, l)	strcasecmp((s1), (s2))
989 #define of_prop_cmp(s1, s2)		strcmp((s1), (s2))
990 #define of_node_cmp(s1, s2)		strcasecmp((s1), (s2))
991 #endif
992 
993 static inline int of_prop_val_eq(struct property *p1, struct property *p2)
994 {
995 	return p1->length == p2->length &&
996 	       !memcmp(p1->value, p2->value, (size_t)p1->length);
997 }
998 
999 #if defined(CONFIG_OF) && defined(CONFIG_NUMA)
1000 extern int of_node_to_nid(struct device_node *np);
1001 #else
1002 static inline int of_node_to_nid(struct device_node *device)
1003 {
1004 	return NUMA_NO_NODE;
1005 }
1006 #endif
1007 
1008 #ifdef CONFIG_OF_NUMA
1009 extern int of_numa_init(void);
1010 #else
1011 static inline int of_numa_init(void)
1012 {
1013 	return -ENOSYS;
1014 }
1015 #endif
1016 
1017 static inline struct device_node *of_find_matching_node(
1018 	struct device_node *from,
1019 	const struct of_device_id *matches)
1020 {
1021 	return of_find_matching_node_and_match(from, matches, NULL);
1022 }
1023 
1024 static inline const char *of_node_get_device_type(const struct device_node *np)
1025 {
1026 	return of_get_property(np, "device_type", NULL);
1027 }
1028 
1029 static inline bool of_node_is_type(const struct device_node *np, const char *type)
1030 {
1031 	const char *match = of_node_get_device_type(np);
1032 
1033 	return np && match && type && !strcmp(match, type);
1034 }
1035 
1036 /**
1037  * of_property_count_u8_elems - Count the number of u8 elements in a property
1038  *
1039  * @np:		device node from which the property value is to be read.
1040  * @propname:	name of the property to be searched.
1041  *
1042  * Search for a property in a device node and count the number of u8 elements
1043  * in it. Returns number of elements on sucess, -EINVAL if the property does
1044  * not exist or its length does not match a multiple of u8 and -ENODATA if the
1045  * property does not have a value.
1046  */
1047 static inline int of_property_count_u8_elems(const struct device_node *np,
1048 				const char *propname)
1049 {
1050 	return of_property_count_elems_of_size(np, propname, sizeof(u8));
1051 }
1052 
1053 /**
1054  * of_property_count_u16_elems - Count the number of u16 elements in a property
1055  *
1056  * @np:		device node from which the property value is to be read.
1057  * @propname:	name of the property to be searched.
1058  *
1059  * Search for a property in a device node and count the number of u16 elements
1060  * in it. Returns number of elements on sucess, -EINVAL if the property does
1061  * not exist or its length does not match a multiple of u16 and -ENODATA if the
1062  * property does not have a value.
1063  */
1064 static inline int of_property_count_u16_elems(const struct device_node *np,
1065 				const char *propname)
1066 {
1067 	return of_property_count_elems_of_size(np, propname, sizeof(u16));
1068 }
1069 
1070 /**
1071  * of_property_count_u32_elems - Count the number of u32 elements in a property
1072  *
1073  * @np:		device node from which the property value is to be read.
1074  * @propname:	name of the property to be searched.
1075  *
1076  * Search for a property in a device node and count the number of u32 elements
1077  * in it. Returns number of elements on sucess, -EINVAL if the property does
1078  * not exist or its length does not match a multiple of u32 and -ENODATA if the
1079  * property does not have a value.
1080  */
1081 static inline int of_property_count_u32_elems(const struct device_node *np,
1082 				const char *propname)
1083 {
1084 	return of_property_count_elems_of_size(np, propname, sizeof(u32));
1085 }
1086 
1087 /**
1088  * of_property_count_u64_elems - Count the number of u64 elements in a property
1089  *
1090  * @np:		device node from which the property value is to be read.
1091  * @propname:	name of the property to be searched.
1092  *
1093  * Search for a property in a device node and count the number of u64 elements
1094  * in it. Returns number of elements on sucess, -EINVAL if the property does
1095  * not exist or its length does not match a multiple of u64 and -ENODATA if the
1096  * property does not have a value.
1097  */
1098 static inline int of_property_count_u64_elems(const struct device_node *np,
1099 				const char *propname)
1100 {
1101 	return of_property_count_elems_of_size(np, propname, sizeof(u64));
1102 }
1103 
1104 /**
1105  * of_property_read_string_array() - Read an array of strings from a multiple
1106  * strings property.
1107  * @np:		device node from which the property value is to be read.
1108  * @propname:	name of the property to be searched.
1109  * @out_strs:	output array of string pointers.
1110  * @sz:		number of array elements to read.
1111  *
1112  * Search for a property in a device tree node and retrieve a list of
1113  * terminated string values (pointer to data, not a copy) in that property.
1114  *
1115  * If @out_strs is NULL, the number of strings in the property is returned.
1116  */
1117 static inline int of_property_read_string_array(const struct device_node *np,
1118 						const char *propname, const char **out_strs,
1119 						size_t sz)
1120 {
1121 	return of_property_read_string_helper(np, propname, out_strs, sz, 0);
1122 }
1123 
1124 /**
1125  * of_property_count_strings() - Find and return the number of strings from a
1126  * multiple strings property.
1127  * @np:		device node from which the property value is to be read.
1128  * @propname:	name of the property to be searched.
1129  *
1130  * Search for a property in a device tree node and retrieve the number of null
1131  * terminated string contain in it. Returns the number of strings on
1132  * success, -EINVAL if the property does not exist, -ENODATA if property
1133  * does not have a value, and -EILSEQ if the string is not null-terminated
1134  * within the length of the property data.
1135  */
1136 static inline int of_property_count_strings(const struct device_node *np,
1137 					    const char *propname)
1138 {
1139 	return of_property_read_string_helper(np, propname, NULL, 0, 0);
1140 }
1141 
1142 /**
1143  * of_property_read_string_index() - Find and read a string from a multiple
1144  * strings property.
1145  * @np:		device node from which the property value is to be read.
1146  * @propname:	name of the property to be searched.
1147  * @index:	index of the string in the list of strings
1148  * @out_string:	pointer to null terminated return string, modified only if
1149  *		return value is 0.
1150  *
1151  * Search for a property in a device tree node and retrieve a null
1152  * terminated string value (pointer to data, not a copy) in the list of strings
1153  * contained in that property.
1154  * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
1155  * property does not have a value, and -EILSEQ if the string is not
1156  * null-terminated within the length of the property data.
1157  *
1158  * The out_string pointer is modified only if a valid string can be decoded.
1159  */
1160 static inline int of_property_read_string_index(const struct device_node *np,
1161 						const char *propname,
1162 						int index, const char **output)
1163 {
1164 	int rc = of_property_read_string_helper(np, propname, output, 1, index);
1165 	return rc < 0 ? rc : 0;
1166 }
1167 
1168 /**
1169  * of_property_read_bool - Findfrom a property
1170  * @np:		device node from which the property value is to be read.
1171  * @propname:	name of the property to be searched.
1172  *
1173  * Search for a property in a device node.
1174  * Returns true if the property exists false otherwise.
1175  */
1176 static inline bool of_property_read_bool(const struct device_node *np,
1177 					 const char *propname)
1178 {
1179 	struct property *prop = of_find_property(np, propname, NULL);
1180 
1181 	return prop ? true : false;
1182 }
1183 
1184 static inline int of_property_read_u8(const struct device_node *np,
1185 				       const char *propname,
1186 				       u8 *out_value)
1187 {
1188 	return of_property_read_u8_array(np, propname, out_value, 1);
1189 }
1190 
1191 static inline int of_property_read_u16(const struct device_node *np,
1192 				       const char *propname,
1193 				       u16 *out_value)
1194 {
1195 	return of_property_read_u16_array(np, propname, out_value, 1);
1196 }
1197 
1198 static inline int of_property_read_u32(const struct device_node *np,
1199 				       const char *propname,
1200 				       u32 *out_value)
1201 {
1202 	return of_property_read_u32_array(np, propname, out_value, 1);
1203 }
1204 
1205 static inline int of_property_read_s32(const struct device_node *np,
1206 				       const char *propname,
1207 				       s32 *out_value)
1208 {
1209 	return of_property_read_u32(np, propname, (u32*) out_value);
1210 }
1211 
1212 #define of_for_each_phandle(it, err, np, ln, cn, cc)			\
1213 	for (of_phandle_iterator_init((it), (np), (ln), (cn), (cc)),	\
1214 	     err = of_phandle_iterator_next(it);			\
1215 	     err == 0;							\
1216 	     err = of_phandle_iterator_next(it))
1217 
1218 #define of_property_for_each_u32(np, propname, prop, p, u)	\
1219 	for (prop = of_find_property(np, propname, NULL),	\
1220 		p = of_prop_next_u32(prop, NULL, &u);		\
1221 		p;						\
1222 		p = of_prop_next_u32(prop, p, &u))
1223 
1224 #define of_property_for_each_string(np, propname, prop, s)	\
1225 	for (prop = of_find_property(np, propname, NULL),	\
1226 		s = of_prop_next_string(prop, NULL);		\
1227 		s;						\
1228 		s = of_prop_next_string(prop, s))
1229 
1230 #define for_each_node_by_name(dn, name) \
1231 	for (dn = of_find_node_by_name(NULL, name); dn; \
1232 	     dn = of_find_node_by_name(dn, name))
1233 #define for_each_node_by_type(dn, type) \
1234 	for (dn = of_find_node_by_type(NULL, type); dn; \
1235 	     dn = of_find_node_by_type(dn, type))
1236 #define for_each_compatible_node(dn, type, compatible) \
1237 	for (dn = of_find_compatible_node(NULL, type, compatible); dn; \
1238 	     dn = of_find_compatible_node(dn, type, compatible))
1239 #define for_each_matching_node(dn, matches) \
1240 	for (dn = of_find_matching_node(NULL, matches); dn; \
1241 	     dn = of_find_matching_node(dn, matches))
1242 #define for_each_matching_node_and_match(dn, matches, match) \
1243 	for (dn = of_find_matching_node_and_match(NULL, matches, match); \
1244 	     dn; dn = of_find_matching_node_and_match(dn, matches, match))
1245 
1246 #define for_each_child_of_node(parent, child) \
1247 	for (child = of_get_next_child(parent, NULL); child != NULL; \
1248 	     child = of_get_next_child(parent, child))
1249 #define for_each_available_child_of_node(parent, child) \
1250 	for (child = of_get_next_available_child(parent, NULL); child != NULL; \
1251 	     child = of_get_next_available_child(parent, child))
1252 
1253 #define for_each_of_cpu_node(cpu) \
1254 	for (cpu = of_get_next_cpu_node(NULL); cpu != NULL; \
1255 	     cpu = of_get_next_cpu_node(cpu))
1256 
1257 #define for_each_node_with_property(dn, prop_name) \
1258 	for (dn = of_find_node_with_property(NULL, prop_name); dn; \
1259 	     dn = of_find_node_with_property(dn, prop_name))
1260 
1261 static inline int of_get_child_count(const struct device_node *np)
1262 {
1263 	struct device_node *child;
1264 	int num = 0;
1265 
1266 	for_each_child_of_node(np, child)
1267 		num++;
1268 
1269 	return num;
1270 }
1271 
1272 static inline int of_get_available_child_count(const struct device_node *np)
1273 {
1274 	struct device_node *child;
1275 	int num = 0;
1276 
1277 	for_each_available_child_of_node(np, child)
1278 		num++;
1279 
1280 	return num;
1281 }
1282 
1283 #if defined(CONFIG_OF) && !defined(MODULE)
1284 #define _OF_DECLARE(table, name, compat, fn, fn_type)			\
1285 	static const struct of_device_id __of_table_##name		\
1286 		__used __section(__##table##_of_table)			\
1287 		 = { .compatible = compat,				\
1288 		     .data = (fn == (fn_type)NULL) ? fn : fn  }
1289 #else
1290 #define _OF_DECLARE(table, name, compat, fn, fn_type)			\
1291 	static const struct of_device_id __of_table_##name		\
1292 		__attribute__((unused))					\
1293 		 = { .compatible = compat,				\
1294 		     .data = (fn == (fn_type)NULL) ? fn : fn }
1295 #endif
1296 
1297 typedef int (*of_init_fn_2)(struct device_node *, struct device_node *);
1298 typedef int (*of_init_fn_1_ret)(struct device_node *);
1299 typedef void (*of_init_fn_1)(struct device_node *);
1300 
1301 #define OF_DECLARE_1(table, name, compat, fn) \
1302 		_OF_DECLARE(table, name, compat, fn, of_init_fn_1)
1303 #define OF_DECLARE_1_RET(table, name, compat, fn) \
1304 		_OF_DECLARE(table, name, compat, fn, of_init_fn_1_ret)
1305 #define OF_DECLARE_2(table, name, compat, fn) \
1306 		_OF_DECLARE(table, name, compat, fn, of_init_fn_2)
1307 
1308 /**
1309  * struct of_changeset_entry	- Holds a changeset entry
1310  *
1311  * @node:	list_head for the log list
1312  * @action:	notifier action
1313  * @np:		pointer to the device node affected
1314  * @prop:	pointer to the property affected
1315  * @old_prop:	hold a pointer to the original property
1316  *
1317  * Every modification of the device tree during a changeset
1318  * is held in a list of of_changeset_entry structures.
1319  * That way we can recover from a partial application, or we can
1320  * revert the changeset
1321  */
1322 struct of_changeset_entry {
1323 	struct list_head node;
1324 	unsigned long action;
1325 	struct device_node *np;
1326 	struct property *prop;
1327 	struct property *old_prop;
1328 };
1329 
1330 /**
1331  * struct of_changeset - changeset tracker structure
1332  *
1333  * @entries:	list_head for the changeset entries
1334  *
1335  * changesets are a convenient way to apply bulk changes to the
1336  * live tree. In case of an error, changes are rolled-back.
1337  * changesets live on after initial application, and if not
1338  * destroyed after use, they can be reverted in one single call.
1339  */
1340 struct of_changeset {
1341 	struct list_head entries;
1342 };
1343 
1344 enum of_reconfig_change {
1345 	OF_RECONFIG_NO_CHANGE = 0,
1346 	OF_RECONFIG_CHANGE_ADD,
1347 	OF_RECONFIG_CHANGE_REMOVE,
1348 };
1349 
1350 #ifdef CONFIG_OF_DYNAMIC
1351 extern int of_reconfig_notifier_register(struct notifier_block *);
1352 extern int of_reconfig_notifier_unregister(struct notifier_block *);
1353 extern int of_reconfig_notify(unsigned long, struct of_reconfig_data *rd);
1354 extern int of_reconfig_get_state_change(unsigned long action,
1355 					struct of_reconfig_data *arg);
1356 
1357 extern void of_changeset_init(struct of_changeset *ocs);
1358 extern void of_changeset_destroy(struct of_changeset *ocs);
1359 extern int of_changeset_apply(struct of_changeset *ocs);
1360 extern int of_changeset_revert(struct of_changeset *ocs);
1361 extern int of_changeset_action(struct of_changeset *ocs,
1362 		unsigned long action, struct device_node *np,
1363 		struct property *prop);
1364 
1365 static inline int of_changeset_attach_node(struct of_changeset *ocs,
1366 		struct device_node *np)
1367 {
1368 	return of_changeset_action(ocs, OF_RECONFIG_ATTACH_NODE, np, NULL);
1369 }
1370 
1371 static inline int of_changeset_detach_node(struct of_changeset *ocs,
1372 		struct device_node *np)
1373 {
1374 	return of_changeset_action(ocs, OF_RECONFIG_DETACH_NODE, np, NULL);
1375 }
1376 
1377 static inline int of_changeset_add_property(struct of_changeset *ocs,
1378 		struct device_node *np, struct property *prop)
1379 {
1380 	return of_changeset_action(ocs, OF_RECONFIG_ADD_PROPERTY, np, prop);
1381 }
1382 
1383 static inline int of_changeset_remove_property(struct of_changeset *ocs,
1384 		struct device_node *np, struct property *prop)
1385 {
1386 	return of_changeset_action(ocs, OF_RECONFIG_REMOVE_PROPERTY, np, prop);
1387 }
1388 
1389 static inline int of_changeset_update_property(struct of_changeset *ocs,
1390 		struct device_node *np, struct property *prop)
1391 {
1392 	return of_changeset_action(ocs, OF_RECONFIG_UPDATE_PROPERTY, np, prop);
1393 }
1394 #else /* CONFIG_OF_DYNAMIC */
1395 static inline int of_reconfig_notifier_register(struct notifier_block *nb)
1396 {
1397 	return -EINVAL;
1398 }
1399 static inline int of_reconfig_notifier_unregister(struct notifier_block *nb)
1400 {
1401 	return -EINVAL;
1402 }
1403 static inline int of_reconfig_notify(unsigned long action,
1404 				     struct of_reconfig_data *arg)
1405 {
1406 	return -EINVAL;
1407 }
1408 static inline int of_reconfig_get_state_change(unsigned long action,
1409 						struct of_reconfig_data *arg)
1410 {
1411 	return -EINVAL;
1412 }
1413 #endif /* CONFIG_OF_DYNAMIC */
1414 
1415 /**
1416  * of_device_is_system_power_controller - Tells if system-power-controller is found for device_node
1417  * @np: Pointer to the given device_node
1418  *
1419  * return true if present false otherwise
1420  */
1421 static inline bool of_device_is_system_power_controller(const struct device_node *np)
1422 {
1423 	return of_property_read_bool(np, "system-power-controller");
1424 }
1425 
1426 /**
1427  * Overlay support
1428  */
1429 
1430 enum of_overlay_notify_action {
1431 	OF_OVERLAY_PRE_APPLY = 0,
1432 	OF_OVERLAY_POST_APPLY,
1433 	OF_OVERLAY_PRE_REMOVE,
1434 	OF_OVERLAY_POST_REMOVE,
1435 };
1436 
1437 struct of_overlay_notify_data {
1438 	struct device_node *overlay;
1439 	struct device_node *target;
1440 };
1441 
1442 #ifdef CONFIG_OF_OVERLAY
1443 
1444 int of_overlay_fdt_apply(const void *overlay_fdt, u32 overlay_fdt_size,
1445 			 int *ovcs_id);
1446 int of_overlay_remove(int *ovcs_id);
1447 int of_overlay_remove_all(void);
1448 
1449 int of_overlay_notifier_register(struct notifier_block *nb);
1450 int of_overlay_notifier_unregister(struct notifier_block *nb);
1451 
1452 #else
1453 
1454 static inline int of_overlay_fdt_apply(void *overlay_fdt, int *ovcs_id)
1455 {
1456 	return -ENOTSUPP;
1457 }
1458 
1459 static inline int of_overlay_remove(int *ovcs_id)
1460 {
1461 	return -ENOTSUPP;
1462 }
1463 
1464 static inline int of_overlay_remove_all(void)
1465 {
1466 	return -ENOTSUPP;
1467 }
1468 
1469 static inline int of_overlay_notifier_register(struct notifier_block *nb)
1470 {
1471 	return 0;
1472 }
1473 
1474 static inline int of_overlay_notifier_unregister(struct notifier_block *nb)
1475 {
1476 	return 0;
1477 }
1478 
1479 #endif
1480 
1481 #endif /* _LINUX_OF_H */
1482