xref: /linux-6.15/include/linux/of.h (revision dfd32cad)
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 	unsigned int unique_id;
70 	struct of_irq_controller *irq_trans;
71 #endif
72 };
73 
74 #define MAX_PHANDLE_ARGS 16
75 struct of_phandle_args {
76 	struct device_node *np;
77 	int args_count;
78 	uint32_t args[MAX_PHANDLE_ARGS];
79 };
80 
81 struct of_phandle_iterator {
82 	/* Common iterator information */
83 	const char *cells_name;
84 	int cell_count;
85 	const struct device_node *parent;
86 
87 	/* List size information */
88 	const __be32 *list_end;
89 	const __be32 *phandle_end;
90 
91 	/* Current position state */
92 	const __be32 *cur;
93 	uint32_t cur_count;
94 	phandle phandle;
95 	struct device_node *node;
96 };
97 
98 struct of_reconfig_data {
99 	struct device_node	*dn;
100 	struct property		*prop;
101 	struct property		*old_prop;
102 };
103 
104 /* initialize a node */
105 extern struct kobj_type of_node_ktype;
106 extern const struct fwnode_operations of_fwnode_ops;
107 static inline void of_node_init(struct device_node *node)
108 {
109 #if defined(CONFIG_OF_KOBJ)
110 	kobject_init(&node->kobj, &of_node_ktype);
111 #endif
112 	node->fwnode.ops = &of_fwnode_ops;
113 }
114 
115 #if defined(CONFIG_OF_KOBJ)
116 #define of_node_kobj(n) (&(n)->kobj)
117 #else
118 #define of_node_kobj(n) NULL
119 #endif
120 
121 #ifdef CONFIG_OF_DYNAMIC
122 extern struct device_node *of_node_get(struct device_node *node);
123 extern void of_node_put(struct device_node *node);
124 #else /* CONFIG_OF_DYNAMIC */
125 /* Dummy ref counting routines - to be implemented later */
126 static inline struct device_node *of_node_get(struct device_node *node)
127 {
128 	return node;
129 }
130 static inline void of_node_put(struct device_node *node) { }
131 #endif /* !CONFIG_OF_DYNAMIC */
132 
133 /* Pointer for first entry in chain of all nodes. */
134 extern struct device_node *of_root;
135 extern struct device_node *of_chosen;
136 extern struct device_node *of_aliases;
137 extern struct device_node *of_stdout;
138 extern raw_spinlock_t devtree_lock;
139 
140 /*
141  * struct device_node flag descriptions
142  * (need to be visible even when !CONFIG_OF)
143  */
144 #define OF_DYNAMIC		1 /* (and properties) allocated via kmalloc */
145 #define OF_DETACHED		2 /* detached from the device tree */
146 #define OF_POPULATED		3 /* device already created */
147 #define OF_POPULATED_BUS	4 /* platform bus created for children */
148 #define OF_OVERLAY		5 /* allocated for an overlay */
149 #define OF_OVERLAY_FREE_CSET	6 /* in overlay cset being freed */
150 
151 #define OF_BAD_ADDR	((u64)-1)
152 
153 #ifdef CONFIG_OF
154 void of_core_init(void);
155 
156 static inline bool is_of_node(const struct fwnode_handle *fwnode)
157 {
158 	return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &of_fwnode_ops;
159 }
160 
161 #define to_of_node(__fwnode)						\
162 	({								\
163 		typeof(__fwnode) __to_of_node_fwnode = (__fwnode);	\
164 									\
165 		is_of_node(__to_of_node_fwnode) ?			\
166 			container_of(__to_of_node_fwnode,		\
167 				     struct device_node, fwnode) :	\
168 			NULL;						\
169 	})
170 
171 #define of_fwnode_handle(node)						\
172 	({								\
173 		typeof(node) __of_fwnode_handle_node = (node);		\
174 									\
175 		__of_fwnode_handle_node ?				\
176 			&__of_fwnode_handle_node->fwnode : NULL;	\
177 	})
178 
179 static inline bool of_have_populated_dt(void)
180 {
181 	return of_root != NULL;
182 }
183 
184 static inline bool of_node_is_root(const struct device_node *node)
185 {
186 	return node && (node->parent == NULL);
187 }
188 
189 static inline int of_node_check_flag(struct device_node *n, unsigned long flag)
190 {
191 	return test_bit(flag, &n->_flags);
192 }
193 
194 static inline int of_node_test_and_set_flag(struct device_node *n,
195 					    unsigned long flag)
196 {
197 	return test_and_set_bit(flag, &n->_flags);
198 }
199 
200 static inline void of_node_set_flag(struct device_node *n, unsigned long flag)
201 {
202 	set_bit(flag, &n->_flags);
203 }
204 
205 static inline void of_node_clear_flag(struct device_node *n, unsigned long flag)
206 {
207 	clear_bit(flag, &n->_flags);
208 }
209 
210 #if defined(CONFIG_OF_DYNAMIC) || defined(CONFIG_SPARC)
211 static inline int of_property_check_flag(struct property *p, unsigned long flag)
212 {
213 	return test_bit(flag, &p->_flags);
214 }
215 
216 static inline void of_property_set_flag(struct property *p, unsigned long flag)
217 {
218 	set_bit(flag, &p->_flags);
219 }
220 
221 static inline void of_property_clear_flag(struct property *p, unsigned long flag)
222 {
223 	clear_bit(flag, &p->_flags);
224 }
225 #endif
226 
227 extern struct device_node *__of_find_all_nodes(struct device_node *prev);
228 extern struct device_node *of_find_all_nodes(struct device_node *prev);
229 
230 /*
231  * OF address retrieval & translation
232  */
233 
234 /* Helper to read a big number; size is in cells (not bytes) */
235 static inline u64 of_read_number(const __be32 *cell, int size)
236 {
237 	u64 r = 0;
238 	while (size--)
239 		r = (r << 32) | be32_to_cpu(*(cell++));
240 	return r;
241 }
242 
243 /* Like of_read_number, but we want an unsigned long result */
244 static inline unsigned long of_read_ulong(const __be32 *cell, int size)
245 {
246 	/* toss away upper bits if unsigned long is smaller than u64 */
247 	return of_read_number(cell, size);
248 }
249 
250 #if defined(CONFIG_SPARC)
251 #include <asm/prom.h>
252 #endif
253 
254 #define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags)
255 #define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags)
256 
257 extern bool of_node_name_eq(const struct device_node *np, const char *name);
258 extern bool of_node_name_prefix(const struct device_node *np, const char *prefix);
259 
260 static inline const char *of_node_full_name(const struct device_node *np)
261 {
262 	return np ? np->full_name : "<no-node>";
263 }
264 
265 #define for_each_of_allnodes_from(from, dn) \
266 	for (dn = __of_find_all_nodes(from); dn; dn = __of_find_all_nodes(dn))
267 #define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn)
268 extern struct device_node *of_find_node_by_name(struct device_node *from,
269 	const char *name);
270 extern struct device_node *of_find_node_by_type(struct device_node *from,
271 	const char *type);
272 extern struct device_node *of_find_compatible_node(struct device_node *from,
273 	const char *type, const char *compat);
274 extern struct device_node *of_find_matching_node_and_match(
275 	struct device_node *from,
276 	const struct of_device_id *matches,
277 	const struct of_device_id **match);
278 
279 extern struct device_node *of_find_node_opts_by_path(const char *path,
280 	const char **opts);
281 static inline struct device_node *of_find_node_by_path(const char *path)
282 {
283 	return of_find_node_opts_by_path(path, NULL);
284 }
285 
286 extern struct device_node *of_find_node_by_phandle(phandle handle);
287 extern struct device_node *of_get_parent(const struct device_node *node);
288 extern struct device_node *of_get_next_parent(struct device_node *node);
289 extern struct device_node *of_get_next_child(const struct device_node *node,
290 					     struct device_node *prev);
291 extern struct device_node *of_get_next_available_child(
292 	const struct device_node *node, struct device_node *prev);
293 
294 extern struct device_node *of_get_compatible_child(const struct device_node *parent,
295 					const char *compatible);
296 extern struct device_node *of_get_child_by_name(const struct device_node *node,
297 					const char *name);
298 
299 /* cache lookup */
300 extern struct device_node *of_find_next_cache_node(const struct device_node *);
301 extern int of_find_last_cache_level(unsigned int cpu);
302 extern struct device_node *of_find_node_with_property(
303 	struct device_node *from, const char *prop_name);
304 
305 extern struct property *of_find_property(const struct device_node *np,
306 					 const char *name,
307 					 int *lenp);
308 extern int of_property_count_elems_of_size(const struct device_node *np,
309 				const char *propname, int elem_size);
310 extern int of_property_read_u32_index(const struct device_node *np,
311 				       const char *propname,
312 				       u32 index, u32 *out_value);
313 extern int of_property_read_u64_index(const struct device_node *np,
314 				       const char *propname,
315 				       u32 index, u64 *out_value);
316 extern int of_property_read_variable_u8_array(const struct device_node *np,
317 					const char *propname, u8 *out_values,
318 					size_t sz_min, size_t sz_max);
319 extern int of_property_read_variable_u16_array(const struct device_node *np,
320 					const char *propname, u16 *out_values,
321 					size_t sz_min, size_t sz_max);
322 extern int of_property_read_variable_u32_array(const struct device_node *np,
323 					const char *propname,
324 					u32 *out_values,
325 					size_t sz_min,
326 					size_t sz_max);
327 extern int of_property_read_u64(const struct device_node *np,
328 				const char *propname, u64 *out_value);
329 extern int of_property_read_variable_u64_array(const struct device_node *np,
330 					const char *propname,
331 					u64 *out_values,
332 					size_t sz_min,
333 					size_t sz_max);
334 
335 extern int of_property_read_string(const struct device_node *np,
336 				   const char *propname,
337 				   const char **out_string);
338 extern int of_property_match_string(const struct device_node *np,
339 				    const char *propname,
340 				    const char *string);
341 extern int of_property_read_string_helper(const struct device_node *np,
342 					      const char *propname,
343 					      const char **out_strs, size_t sz, int index);
344 extern int of_device_is_compatible(const struct device_node *device,
345 				   const char *);
346 extern int of_device_compatible_match(struct device_node *device,
347 				      const char *const *compat);
348 extern bool of_device_is_available(const struct device_node *device);
349 extern bool of_device_is_big_endian(const struct device_node *device);
350 extern const void *of_get_property(const struct device_node *node,
351 				const char *name,
352 				int *lenp);
353 extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread);
354 extern struct device_node *of_get_next_cpu_node(struct device_node *prev);
355 
356 #define for_each_property_of_node(dn, pp) \
357 	for (pp = dn->properties; pp != NULL; pp = pp->next)
358 
359 extern int of_n_addr_cells(struct device_node *np);
360 extern int of_n_size_cells(struct device_node *np);
361 extern const struct of_device_id *of_match_node(
362 	const struct of_device_id *matches, const struct device_node *node);
363 extern int of_modalias_node(struct device_node *node, char *modalias, int len);
364 extern void of_print_phandle_args(const char *msg, const struct of_phandle_args *args);
365 extern struct device_node *of_parse_phandle(const struct device_node *np,
366 					    const char *phandle_name,
367 					    int index);
368 extern int of_parse_phandle_with_args(const struct device_node *np,
369 	const char *list_name, const char *cells_name, int index,
370 	struct of_phandle_args *out_args);
371 extern int of_parse_phandle_with_args_map(const struct device_node *np,
372 	const char *list_name, const char *stem_name, int index,
373 	struct of_phandle_args *out_args);
374 extern int of_parse_phandle_with_fixed_args(const struct device_node *np,
375 	const char *list_name, int cells_count, int index,
376 	struct of_phandle_args *out_args);
377 extern int of_count_phandle_with_args(const struct device_node *np,
378 	const char *list_name, const char *cells_name);
379 
380 /* phandle iterator functions */
381 extern int of_phandle_iterator_init(struct of_phandle_iterator *it,
382 				    const struct device_node *np,
383 				    const char *list_name,
384 				    const char *cells_name,
385 				    int cell_count);
386 
387 extern int of_phandle_iterator_next(struct of_phandle_iterator *it);
388 extern int of_phandle_iterator_args(struct of_phandle_iterator *it,
389 				    uint32_t *args,
390 				    int size);
391 
392 extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align));
393 extern int of_alias_get_id(struct device_node *np, const char *stem);
394 extern int of_alias_get_highest_id(const char *stem);
395 extern int of_alias_get_alias_list(const struct of_device_id *matches,
396 				   const char *stem, unsigned long *bitmap,
397 				   unsigned int nbits);
398 
399 extern int of_machine_is_compatible(const char *compat);
400 
401 extern int of_add_property(struct device_node *np, struct property *prop);
402 extern int of_remove_property(struct device_node *np, struct property *prop);
403 extern int of_update_property(struct device_node *np, struct property *newprop);
404 
405 /* For updating the device tree at runtime */
406 #define OF_RECONFIG_ATTACH_NODE		0x0001
407 #define OF_RECONFIG_DETACH_NODE		0x0002
408 #define OF_RECONFIG_ADD_PROPERTY	0x0003
409 #define OF_RECONFIG_REMOVE_PROPERTY	0x0004
410 #define OF_RECONFIG_UPDATE_PROPERTY	0x0005
411 
412 extern int of_attach_node(struct device_node *);
413 extern int of_detach_node(struct device_node *);
414 
415 #define of_match_ptr(_ptr)	(_ptr)
416 
417 /**
418  * of_property_read_u8_array - Find and read an array of u8 from a property.
419  *
420  * @np:		device node from which the property value is to be read.
421  * @propname:	name of the property to be searched.
422  * @out_values:	pointer to return value, modified only if return value is 0.
423  * @sz:		number of array elements to read
424  *
425  * Search for a property in a device node and read 8-bit value(s) from
426  * it. Returns 0 on success, -EINVAL if the property does not exist,
427  * -ENODATA if property does not have a value, and -EOVERFLOW if the
428  * property data isn't large enough.
429  *
430  * dts entry of array should be like:
431  *	property = /bits/ 8 <0x50 0x60 0x70>;
432  *
433  * The out_values is modified only if a valid u8 value can be decoded.
434  */
435 static inline int of_property_read_u8_array(const struct device_node *np,
436 					    const char *propname,
437 					    u8 *out_values, size_t sz)
438 {
439 	int ret = of_property_read_variable_u8_array(np, propname, out_values,
440 						     sz, 0);
441 	if (ret >= 0)
442 		return 0;
443 	else
444 		return ret;
445 }
446 
447 /**
448  * of_property_read_u16_array - Find and read an array of u16 from a property.
449  *
450  * @np:		device node from which the property value is to be read.
451  * @propname:	name of the property to be searched.
452  * @out_values:	pointer to return value, modified only if return value is 0.
453  * @sz:		number of array elements to read
454  *
455  * Search for a property in a device node and read 16-bit value(s) from
456  * it. Returns 0 on success, -EINVAL if the property does not exist,
457  * -ENODATA if property does not have a value, and -EOVERFLOW if the
458  * property data isn't large enough.
459  *
460  * dts entry of array should be like:
461  *	property = /bits/ 16 <0x5000 0x6000 0x7000>;
462  *
463  * The out_values is modified only if a valid u16 value can be decoded.
464  */
465 static inline int of_property_read_u16_array(const struct device_node *np,
466 					     const char *propname,
467 					     u16 *out_values, size_t sz)
468 {
469 	int ret = of_property_read_variable_u16_array(np, propname, out_values,
470 						      sz, 0);
471 	if (ret >= 0)
472 		return 0;
473 	else
474 		return ret;
475 }
476 
477 /**
478  * of_property_read_u32_array - Find and read an array of 32 bit integers
479  * from a property.
480  *
481  * @np:		device node from which the property value is to be read.
482  * @propname:	name of the property to be searched.
483  * @out_values:	pointer to return value, modified only if return value is 0.
484  * @sz:		number of array elements to read
485  *
486  * Search for a property in a device node and read 32-bit value(s) from
487  * it. Returns 0 on success, -EINVAL if the property does not exist,
488  * -ENODATA if property does not have a value, and -EOVERFLOW if the
489  * property data isn't large enough.
490  *
491  * The out_values is modified only if a valid u32 value can be decoded.
492  */
493 static inline int of_property_read_u32_array(const struct device_node *np,
494 					     const char *propname,
495 					     u32 *out_values, size_t sz)
496 {
497 	int ret = of_property_read_variable_u32_array(np, propname, out_values,
498 						      sz, 0);
499 	if (ret >= 0)
500 		return 0;
501 	else
502 		return ret;
503 }
504 
505 /**
506  * of_property_read_u64_array - Find and read an array of 64 bit integers
507  * from a property.
508  *
509  * @np:		device node from which the property value is to be read.
510  * @propname:	name of the property to be searched.
511  * @out_values:	pointer to return value, modified only if return value is 0.
512  * @sz:		number of array elements to read
513  *
514  * Search for a property in a device node and read 64-bit value(s) from
515  * it. Returns 0 on success, -EINVAL if the property does not exist,
516  * -ENODATA if property does not have a value, and -EOVERFLOW if the
517  * property data isn't large enough.
518  *
519  * The out_values is modified only if a valid u64 value can be decoded.
520  */
521 static inline int of_property_read_u64_array(const struct device_node *np,
522 					     const char *propname,
523 					     u64 *out_values, size_t sz)
524 {
525 	int ret = of_property_read_variable_u64_array(np, propname, out_values,
526 						      sz, 0);
527 	if (ret >= 0)
528 		return 0;
529 	else
530 		return ret;
531 }
532 
533 /*
534  * struct property *prop;
535  * const __be32 *p;
536  * u32 u;
537  *
538  * of_property_for_each_u32(np, "propname", prop, p, u)
539  *         printk("U32 value: %x\n", u);
540  */
541 const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
542 			       u32 *pu);
543 /*
544  * struct property *prop;
545  * const char *s;
546  *
547  * of_property_for_each_string(np, "propname", prop, s)
548  *         printk("String value: %s\n", s);
549  */
550 const char *of_prop_next_string(struct property *prop, const char *cur);
551 
552 bool of_console_check(struct device_node *dn, char *name, int index);
553 
554 extern int of_cpu_node_to_id(struct device_node *np);
555 
556 int of_map_rid(struct device_node *np, u32 rid,
557 	       const char *map_name, const char *map_mask_name,
558 	       struct device_node **target, u32 *id_out);
559 
560 #else /* CONFIG_OF */
561 
562 static inline void of_core_init(void)
563 {
564 }
565 
566 static inline bool is_of_node(const struct fwnode_handle *fwnode)
567 {
568 	return false;
569 }
570 
571 static inline struct device_node *to_of_node(const struct fwnode_handle *fwnode)
572 {
573 	return NULL;
574 }
575 
576 static inline bool of_node_name_eq(const struct device_node *np, const char *name)
577 {
578 	return false;
579 }
580 
581 static inline bool of_node_name_prefix(const struct device_node *np, const char *prefix)
582 {
583 	return false;
584 }
585 
586 static inline const char* of_node_full_name(const struct device_node *np)
587 {
588 	return "<no-node>";
589 }
590 
591 static inline struct device_node *of_find_node_by_name(struct device_node *from,
592 	const char *name)
593 {
594 	return NULL;
595 }
596 
597 static inline struct device_node *of_find_node_by_type(struct device_node *from,
598 	const char *type)
599 {
600 	return NULL;
601 }
602 
603 static inline struct device_node *of_find_matching_node_and_match(
604 	struct device_node *from,
605 	const struct of_device_id *matches,
606 	const struct of_device_id **match)
607 {
608 	return NULL;
609 }
610 
611 static inline struct device_node *of_find_node_by_path(const char *path)
612 {
613 	return NULL;
614 }
615 
616 static inline struct device_node *of_find_node_opts_by_path(const char *path,
617 	const char **opts)
618 {
619 	return NULL;
620 }
621 
622 static inline struct device_node *of_find_node_by_phandle(phandle handle)
623 {
624 	return NULL;
625 }
626 
627 static inline struct device_node *of_get_parent(const struct device_node *node)
628 {
629 	return NULL;
630 }
631 
632 static inline struct device_node *of_get_next_child(
633 	const struct device_node *node, struct device_node *prev)
634 {
635 	return NULL;
636 }
637 
638 static inline struct device_node *of_get_next_available_child(
639 	const struct device_node *node, struct device_node *prev)
640 {
641 	return NULL;
642 }
643 
644 static inline struct device_node *of_find_node_with_property(
645 	struct device_node *from, const char *prop_name)
646 {
647 	return NULL;
648 }
649 
650 #define of_fwnode_handle(node) NULL
651 
652 static inline bool of_have_populated_dt(void)
653 {
654 	return false;
655 }
656 
657 static inline struct device_node *of_get_compatible_child(const struct device_node *parent,
658 					const char *compatible)
659 {
660 	return NULL;
661 }
662 
663 static inline struct device_node *of_get_child_by_name(
664 					const struct device_node *node,
665 					const char *name)
666 {
667 	return NULL;
668 }
669 
670 static inline int of_device_is_compatible(const struct device_node *device,
671 					  const char *name)
672 {
673 	return 0;
674 }
675 
676 static inline  int of_device_compatible_match(struct device_node *device,
677 					      const char *const *compat)
678 {
679 	return 0;
680 }
681 
682 static inline bool of_device_is_available(const struct device_node *device)
683 {
684 	return false;
685 }
686 
687 static inline bool of_device_is_big_endian(const struct device_node *device)
688 {
689 	return false;
690 }
691 
692 static inline struct property *of_find_property(const struct device_node *np,
693 						const char *name,
694 						int *lenp)
695 {
696 	return NULL;
697 }
698 
699 static inline struct device_node *of_find_compatible_node(
700 						struct device_node *from,
701 						const char *type,
702 						const char *compat)
703 {
704 	return NULL;
705 }
706 
707 static inline int of_property_count_elems_of_size(const struct device_node *np,
708 			const char *propname, int elem_size)
709 {
710 	return -ENOSYS;
711 }
712 
713 static inline int of_property_read_u8_array(const struct device_node *np,
714 			const char *propname, u8 *out_values, size_t sz)
715 {
716 	return -ENOSYS;
717 }
718 
719 static inline int of_property_read_u16_array(const struct device_node *np,
720 			const char *propname, u16 *out_values, size_t sz)
721 {
722 	return -ENOSYS;
723 }
724 
725 static inline int of_property_read_u32_array(const struct device_node *np,
726 					     const char *propname,
727 					     u32 *out_values, size_t sz)
728 {
729 	return -ENOSYS;
730 }
731 
732 static inline int of_property_read_u64_array(const struct device_node *np,
733 					     const char *propname,
734 					     u64 *out_values, size_t sz)
735 {
736 	return -ENOSYS;
737 }
738 
739 static inline int of_property_read_u32_index(const struct device_node *np,
740 			const char *propname, u32 index, u32 *out_value)
741 {
742 	return -ENOSYS;
743 }
744 
745 static inline int of_property_read_u64_index(const struct device_node *np,
746 			const char *propname, u32 index, u64 *out_value)
747 {
748 	return -ENOSYS;
749 }
750 
751 static inline const void *of_get_property(const struct device_node *node,
752 				const char *name,
753 				int *lenp)
754 {
755 	return NULL;
756 }
757 
758 static inline struct device_node *of_get_cpu_node(int cpu,
759 					unsigned int *thread)
760 {
761 	return NULL;
762 }
763 
764 static inline struct device_node *of_get_next_cpu_node(struct device_node *prev)
765 {
766 	return NULL;
767 }
768 
769 static inline int of_n_addr_cells(struct device_node *np)
770 {
771 	return 0;
772 
773 }
774 static inline int of_n_size_cells(struct device_node *np)
775 {
776 	return 0;
777 }
778 
779 static inline int of_property_read_variable_u8_array(const struct device_node *np,
780 					const char *propname, u8 *out_values,
781 					size_t sz_min, size_t sz_max)
782 {
783 	return -ENOSYS;
784 }
785 
786 static inline int of_property_read_variable_u16_array(const struct device_node *np,
787 					const char *propname, u16 *out_values,
788 					size_t sz_min, size_t sz_max)
789 {
790 	return -ENOSYS;
791 }
792 
793 static inline int of_property_read_variable_u32_array(const struct device_node *np,
794 					const char *propname,
795 					u32 *out_values,
796 					size_t sz_min,
797 					size_t sz_max)
798 {
799 	return -ENOSYS;
800 }
801 
802 static inline int of_property_read_u64(const struct device_node *np,
803 				       const char *propname, u64 *out_value)
804 {
805 	return -ENOSYS;
806 }
807 
808 static inline int of_property_read_variable_u64_array(const struct device_node *np,
809 					const char *propname,
810 					u64 *out_values,
811 					size_t sz_min,
812 					size_t sz_max)
813 {
814 	return -ENOSYS;
815 }
816 
817 static inline int of_property_read_string(const struct device_node *np,
818 					  const char *propname,
819 					  const char **out_string)
820 {
821 	return -ENOSYS;
822 }
823 
824 static inline int of_property_match_string(const struct device_node *np,
825 					   const char *propname,
826 					   const char *string)
827 {
828 	return -ENOSYS;
829 }
830 
831 static inline int of_property_read_string_helper(const struct device_node *np,
832 						 const char *propname,
833 						 const char **out_strs, size_t sz, int index)
834 {
835 	return -ENOSYS;
836 }
837 
838 static inline struct device_node *of_parse_phandle(const struct device_node *np,
839 						   const char *phandle_name,
840 						   int index)
841 {
842 	return NULL;
843 }
844 
845 static inline int of_parse_phandle_with_args(const struct device_node *np,
846 					     const char *list_name,
847 					     const char *cells_name,
848 					     int index,
849 					     struct of_phandle_args *out_args)
850 {
851 	return -ENOSYS;
852 }
853 
854 static inline int of_parse_phandle_with_args_map(const struct device_node *np,
855 						 const char *list_name,
856 						 const char *stem_name,
857 						 int index,
858 						 struct of_phandle_args *out_args)
859 {
860 	return -ENOSYS;
861 }
862 
863 static inline int of_parse_phandle_with_fixed_args(const struct device_node *np,
864 	const char *list_name, int cells_count, int index,
865 	struct of_phandle_args *out_args)
866 {
867 	return -ENOSYS;
868 }
869 
870 static inline int of_count_phandle_with_args(struct device_node *np,
871 					     const char *list_name,
872 					     const char *cells_name)
873 {
874 	return -ENOSYS;
875 }
876 
877 static inline int of_phandle_iterator_init(struct of_phandle_iterator *it,
878 					   const struct device_node *np,
879 					   const char *list_name,
880 					   const char *cells_name,
881 					   int cell_count)
882 {
883 	return -ENOSYS;
884 }
885 
886 static inline int of_phandle_iterator_next(struct of_phandle_iterator *it)
887 {
888 	return -ENOSYS;
889 }
890 
891 static inline int of_phandle_iterator_args(struct of_phandle_iterator *it,
892 					   uint32_t *args,
893 					   int size)
894 {
895 	return 0;
896 }
897 
898 static inline int of_alias_get_id(struct device_node *np, const char *stem)
899 {
900 	return -ENOSYS;
901 }
902 
903 static inline int of_alias_get_highest_id(const char *stem)
904 {
905 	return -ENOSYS;
906 }
907 
908 static inline int of_alias_get_alias_list(const struct of_device_id *matches,
909 					  const char *stem, unsigned long *bitmap,
910 					  unsigned int nbits)
911 {
912 	return -ENOSYS;
913 }
914 
915 static inline int of_machine_is_compatible(const char *compat)
916 {
917 	return 0;
918 }
919 
920 static inline bool of_console_check(const struct device_node *dn, const char *name, int index)
921 {
922 	return false;
923 }
924 
925 static inline const __be32 *of_prop_next_u32(struct property *prop,
926 		const __be32 *cur, u32 *pu)
927 {
928 	return NULL;
929 }
930 
931 static inline const char *of_prop_next_string(struct property *prop,
932 		const char *cur)
933 {
934 	return NULL;
935 }
936 
937 static inline int of_node_check_flag(struct device_node *n, unsigned long flag)
938 {
939 	return 0;
940 }
941 
942 static inline int of_node_test_and_set_flag(struct device_node *n,
943 					    unsigned long flag)
944 {
945 	return 0;
946 }
947 
948 static inline void of_node_set_flag(struct device_node *n, unsigned long flag)
949 {
950 }
951 
952 static inline void of_node_clear_flag(struct device_node *n, unsigned long flag)
953 {
954 }
955 
956 static inline int of_property_check_flag(struct property *p, unsigned long flag)
957 {
958 	return 0;
959 }
960 
961 static inline void of_property_set_flag(struct property *p, unsigned long flag)
962 {
963 }
964 
965 static inline void of_property_clear_flag(struct property *p, unsigned long flag)
966 {
967 }
968 
969 static inline int of_cpu_node_to_id(struct device_node *np)
970 {
971 	return -ENODEV;
972 }
973 
974 static inline int of_map_rid(struct device_node *np, u32 rid,
975 			     const char *map_name, const char *map_mask_name,
976 			     struct device_node **target, u32 *id_out)
977 {
978 	return -EINVAL;
979 }
980 
981 #define of_match_ptr(_ptr)	NULL
982 #define of_match_node(_matches, _node)	NULL
983 #endif /* CONFIG_OF */
984 
985 /* Default string compare functions, Allow arch asm/prom.h to override */
986 #if !defined(of_compat_cmp)
987 #define of_compat_cmp(s1, s2, l)	strcasecmp((s1), (s2))
988 #define of_prop_cmp(s1, s2)		strcmp((s1), (s2))
989 #define of_node_cmp(s1, s2)		strcasecmp((s1), (s2))
990 #endif
991 
992 static inline int of_prop_val_eq(struct property *p1, struct property *p2)
993 {
994 	return p1->length == p2->length &&
995 	       !memcmp(p1->value, p2->value, (size_t)p1->length);
996 }
997 
998 #if defined(CONFIG_OF) && defined(CONFIG_NUMA)
999 extern int of_node_to_nid(struct device_node *np);
1000 #else
1001 static inline int of_node_to_nid(struct device_node *device)
1002 {
1003 	return NUMA_NO_NODE;
1004 }
1005 #endif
1006 
1007 #ifdef CONFIG_OF_NUMA
1008 extern int of_numa_init(void);
1009 #else
1010 static inline int of_numa_init(void)
1011 {
1012 	return -ENOSYS;
1013 }
1014 #endif
1015 
1016 static inline struct device_node *of_find_matching_node(
1017 	struct device_node *from,
1018 	const struct of_device_id *matches)
1019 {
1020 	return of_find_matching_node_and_match(from, matches, NULL);
1021 }
1022 
1023 static inline const char *of_node_get_device_type(const struct device_node *np)
1024 {
1025 	return of_get_property(np, "device_type", NULL);
1026 }
1027 
1028 static inline bool of_node_is_type(const struct device_node *np, const char *type)
1029 {
1030 	const char *match = of_node_get_device_type(np);
1031 
1032 	return np && match && type && !strcmp(match, type);
1033 }
1034 
1035 /**
1036  * of_property_count_u8_elems - Count the number of u8 elements in a property
1037  *
1038  * @np:		device node from which the property value is to be read.
1039  * @propname:	name of the property to be searched.
1040  *
1041  * Search for a property in a device node and count the number of u8 elements
1042  * in it. Returns number of elements on sucess, -EINVAL if the property does
1043  * not exist or its length does not match a multiple of u8 and -ENODATA if the
1044  * property does not have a value.
1045  */
1046 static inline int of_property_count_u8_elems(const struct device_node *np,
1047 				const char *propname)
1048 {
1049 	return of_property_count_elems_of_size(np, propname, sizeof(u8));
1050 }
1051 
1052 /**
1053  * of_property_count_u16_elems - Count the number of u16 elements in a property
1054  *
1055  * @np:		device node from which the property value is to be read.
1056  * @propname:	name of the property to be searched.
1057  *
1058  * Search for a property in a device node and count the number of u16 elements
1059  * in it. Returns number of elements on sucess, -EINVAL if the property does
1060  * not exist or its length does not match a multiple of u16 and -ENODATA if the
1061  * property does not have a value.
1062  */
1063 static inline int of_property_count_u16_elems(const struct device_node *np,
1064 				const char *propname)
1065 {
1066 	return of_property_count_elems_of_size(np, propname, sizeof(u16));
1067 }
1068 
1069 /**
1070  * of_property_count_u32_elems - Count the number of u32 elements in a property
1071  *
1072  * @np:		device node from which the property value is to be read.
1073  * @propname:	name of the property to be searched.
1074  *
1075  * Search for a property in a device node and count the number of u32 elements
1076  * in it. Returns number of elements on sucess, -EINVAL if the property does
1077  * not exist or its length does not match a multiple of u32 and -ENODATA if the
1078  * property does not have a value.
1079  */
1080 static inline int of_property_count_u32_elems(const struct device_node *np,
1081 				const char *propname)
1082 {
1083 	return of_property_count_elems_of_size(np, propname, sizeof(u32));
1084 }
1085 
1086 /**
1087  * of_property_count_u64_elems - Count the number of u64 elements in a property
1088  *
1089  * @np:		device node from which the property value is to be read.
1090  * @propname:	name of the property to be searched.
1091  *
1092  * Search for a property in a device node and count the number of u64 elements
1093  * in it. Returns number of elements on sucess, -EINVAL if the property does
1094  * not exist or its length does not match a multiple of u64 and -ENODATA if the
1095  * property does not have a value.
1096  */
1097 static inline int of_property_count_u64_elems(const struct device_node *np,
1098 				const char *propname)
1099 {
1100 	return of_property_count_elems_of_size(np, propname, sizeof(u64));
1101 }
1102 
1103 /**
1104  * of_property_read_string_array() - Read an array of strings from a multiple
1105  * strings property.
1106  * @np:		device node from which the property value is to be read.
1107  * @propname:	name of the property to be searched.
1108  * @out_strs:	output array of string pointers.
1109  * @sz:		number of array elements to read.
1110  *
1111  * Search for a property in a device tree node and retrieve a list of
1112  * terminated string values (pointer to data, not a copy) in that property.
1113  *
1114  * If @out_strs is NULL, the number of strings in the property is returned.
1115  */
1116 static inline int of_property_read_string_array(const struct device_node *np,
1117 						const char *propname, const char **out_strs,
1118 						size_t sz)
1119 {
1120 	return of_property_read_string_helper(np, propname, out_strs, sz, 0);
1121 }
1122 
1123 /**
1124  * of_property_count_strings() - Find and return the number of strings from a
1125  * multiple strings property.
1126  * @np:		device node from which the property value is to be read.
1127  * @propname:	name of the property to be searched.
1128  *
1129  * Search for a property in a device tree node and retrieve the number of null
1130  * terminated string contain in it. Returns the number of strings on
1131  * success, -EINVAL if the property does not exist, -ENODATA if property
1132  * does not have a value, and -EILSEQ if the string is not null-terminated
1133  * within the length of the property data.
1134  */
1135 static inline int of_property_count_strings(const struct device_node *np,
1136 					    const char *propname)
1137 {
1138 	return of_property_read_string_helper(np, propname, NULL, 0, 0);
1139 }
1140 
1141 /**
1142  * of_property_read_string_index() - Find and read a string from a multiple
1143  * strings property.
1144  * @np:		device node from which the property value is to be read.
1145  * @propname:	name of the property to be searched.
1146  * @index:	index of the string in the list of strings
1147  * @out_string:	pointer to null terminated return string, modified only if
1148  *		return value is 0.
1149  *
1150  * Search for a property in a device tree node and retrieve a null
1151  * terminated string value (pointer to data, not a copy) in the list of strings
1152  * contained in that property.
1153  * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
1154  * property does not have a value, and -EILSEQ if the string is not
1155  * null-terminated within the length of the property data.
1156  *
1157  * The out_string pointer is modified only if a valid string can be decoded.
1158  */
1159 static inline int of_property_read_string_index(const struct device_node *np,
1160 						const char *propname,
1161 						int index, const char **output)
1162 {
1163 	int rc = of_property_read_string_helper(np, propname, output, 1, index);
1164 	return rc < 0 ? rc : 0;
1165 }
1166 
1167 /**
1168  * of_property_read_bool - Findfrom a property
1169  * @np:		device node from which the property value is to be read.
1170  * @propname:	name of the property to be searched.
1171  *
1172  * Search for a property in a device node.
1173  * Returns true if the property exists false otherwise.
1174  */
1175 static inline bool of_property_read_bool(const struct device_node *np,
1176 					 const char *propname)
1177 {
1178 	struct property *prop = of_find_property(np, propname, NULL);
1179 
1180 	return prop ? true : false;
1181 }
1182 
1183 static inline int of_property_read_u8(const struct device_node *np,
1184 				       const char *propname,
1185 				       u8 *out_value)
1186 {
1187 	return of_property_read_u8_array(np, propname, out_value, 1);
1188 }
1189 
1190 static inline int of_property_read_u16(const struct device_node *np,
1191 				       const char *propname,
1192 				       u16 *out_value)
1193 {
1194 	return of_property_read_u16_array(np, propname, out_value, 1);
1195 }
1196 
1197 static inline int of_property_read_u32(const struct device_node *np,
1198 				       const char *propname,
1199 				       u32 *out_value)
1200 {
1201 	return of_property_read_u32_array(np, propname, out_value, 1);
1202 }
1203 
1204 static inline int of_property_read_s32(const struct device_node *np,
1205 				       const char *propname,
1206 				       s32 *out_value)
1207 {
1208 	return of_property_read_u32(np, propname, (u32*) out_value);
1209 }
1210 
1211 #define of_for_each_phandle(it, err, np, ln, cn, cc)			\
1212 	for (of_phandle_iterator_init((it), (np), (ln), (cn), (cc)),	\
1213 	     err = of_phandle_iterator_next(it);			\
1214 	     err == 0;							\
1215 	     err = of_phandle_iterator_next(it))
1216 
1217 #define of_property_for_each_u32(np, propname, prop, p, u)	\
1218 	for (prop = of_find_property(np, propname, NULL),	\
1219 		p = of_prop_next_u32(prop, NULL, &u);		\
1220 		p;						\
1221 		p = of_prop_next_u32(prop, p, &u))
1222 
1223 #define of_property_for_each_string(np, propname, prop, s)	\
1224 	for (prop = of_find_property(np, propname, NULL),	\
1225 		s = of_prop_next_string(prop, NULL);		\
1226 		s;						\
1227 		s = of_prop_next_string(prop, s))
1228 
1229 #define for_each_node_by_name(dn, name) \
1230 	for (dn = of_find_node_by_name(NULL, name); dn; \
1231 	     dn = of_find_node_by_name(dn, name))
1232 #define for_each_node_by_type(dn, type) \
1233 	for (dn = of_find_node_by_type(NULL, type); dn; \
1234 	     dn = of_find_node_by_type(dn, type))
1235 #define for_each_compatible_node(dn, type, compatible) \
1236 	for (dn = of_find_compatible_node(NULL, type, compatible); dn; \
1237 	     dn = of_find_compatible_node(dn, type, compatible))
1238 #define for_each_matching_node(dn, matches) \
1239 	for (dn = of_find_matching_node(NULL, matches); dn; \
1240 	     dn = of_find_matching_node(dn, matches))
1241 #define for_each_matching_node_and_match(dn, matches, match) \
1242 	for (dn = of_find_matching_node_and_match(NULL, matches, match); \
1243 	     dn; dn = of_find_matching_node_and_match(dn, matches, match))
1244 
1245 #define for_each_child_of_node(parent, child) \
1246 	for (child = of_get_next_child(parent, NULL); child != NULL; \
1247 	     child = of_get_next_child(parent, child))
1248 #define for_each_available_child_of_node(parent, child) \
1249 	for (child = of_get_next_available_child(parent, NULL); child != NULL; \
1250 	     child = of_get_next_available_child(parent, child))
1251 
1252 #define for_each_of_cpu_node(cpu) \
1253 	for (cpu = of_get_next_cpu_node(NULL); cpu != NULL; \
1254 	     cpu = of_get_next_cpu_node(cpu))
1255 
1256 #define for_each_node_with_property(dn, prop_name) \
1257 	for (dn = of_find_node_with_property(NULL, prop_name); dn; \
1258 	     dn = of_find_node_with_property(dn, prop_name))
1259 
1260 static inline int of_get_child_count(const struct device_node *np)
1261 {
1262 	struct device_node *child;
1263 	int num = 0;
1264 
1265 	for_each_child_of_node(np, child)
1266 		num++;
1267 
1268 	return num;
1269 }
1270 
1271 static inline int of_get_available_child_count(const struct device_node *np)
1272 {
1273 	struct device_node *child;
1274 	int num = 0;
1275 
1276 	for_each_available_child_of_node(np, child)
1277 		num++;
1278 
1279 	return num;
1280 }
1281 
1282 #if defined(CONFIG_OF) && !defined(MODULE)
1283 #define _OF_DECLARE(table, name, compat, fn, fn_type)			\
1284 	static const struct of_device_id __of_table_##name		\
1285 		__used __section(__##table##_of_table)			\
1286 		 = { .compatible = compat,				\
1287 		     .data = (fn == (fn_type)NULL) ? fn : fn  }
1288 #else
1289 #define _OF_DECLARE(table, name, compat, fn, fn_type)			\
1290 	static const struct of_device_id __of_table_##name		\
1291 		__attribute__((unused))					\
1292 		 = { .compatible = compat,				\
1293 		     .data = (fn == (fn_type)NULL) ? fn : fn }
1294 #endif
1295 
1296 typedef int (*of_init_fn_2)(struct device_node *, struct device_node *);
1297 typedef int (*of_init_fn_1_ret)(struct device_node *);
1298 typedef void (*of_init_fn_1)(struct device_node *);
1299 
1300 #define OF_DECLARE_1(table, name, compat, fn) \
1301 		_OF_DECLARE(table, name, compat, fn, of_init_fn_1)
1302 #define OF_DECLARE_1_RET(table, name, compat, fn) \
1303 		_OF_DECLARE(table, name, compat, fn, of_init_fn_1_ret)
1304 #define OF_DECLARE_2(table, name, compat, fn) \
1305 		_OF_DECLARE(table, name, compat, fn, of_init_fn_2)
1306 
1307 /**
1308  * struct of_changeset_entry	- Holds a changeset entry
1309  *
1310  * @node:	list_head for the log list
1311  * @action:	notifier action
1312  * @np:		pointer to the device node affected
1313  * @prop:	pointer to the property affected
1314  * @old_prop:	hold a pointer to the original property
1315  *
1316  * Every modification of the device tree during a changeset
1317  * is held in a list of of_changeset_entry structures.
1318  * That way we can recover from a partial application, or we can
1319  * revert the changeset
1320  */
1321 struct of_changeset_entry {
1322 	struct list_head node;
1323 	unsigned long action;
1324 	struct device_node *np;
1325 	struct property *prop;
1326 	struct property *old_prop;
1327 };
1328 
1329 /**
1330  * struct of_changeset - changeset tracker structure
1331  *
1332  * @entries:	list_head for the changeset entries
1333  *
1334  * changesets are a convenient way to apply bulk changes to the
1335  * live tree. In case of an error, changes are rolled-back.
1336  * changesets live on after initial application, and if not
1337  * destroyed after use, they can be reverted in one single call.
1338  */
1339 struct of_changeset {
1340 	struct list_head entries;
1341 };
1342 
1343 enum of_reconfig_change {
1344 	OF_RECONFIG_NO_CHANGE = 0,
1345 	OF_RECONFIG_CHANGE_ADD,
1346 	OF_RECONFIG_CHANGE_REMOVE,
1347 };
1348 
1349 #ifdef CONFIG_OF_DYNAMIC
1350 extern int of_reconfig_notifier_register(struct notifier_block *);
1351 extern int of_reconfig_notifier_unregister(struct notifier_block *);
1352 extern int of_reconfig_notify(unsigned long, struct of_reconfig_data *rd);
1353 extern int of_reconfig_get_state_change(unsigned long action,
1354 					struct of_reconfig_data *arg);
1355 
1356 extern void of_changeset_init(struct of_changeset *ocs);
1357 extern void of_changeset_destroy(struct of_changeset *ocs);
1358 extern int of_changeset_apply(struct of_changeset *ocs);
1359 extern int of_changeset_revert(struct of_changeset *ocs);
1360 extern int of_changeset_action(struct of_changeset *ocs,
1361 		unsigned long action, struct device_node *np,
1362 		struct property *prop);
1363 
1364 static inline int of_changeset_attach_node(struct of_changeset *ocs,
1365 		struct device_node *np)
1366 {
1367 	return of_changeset_action(ocs, OF_RECONFIG_ATTACH_NODE, np, NULL);
1368 }
1369 
1370 static inline int of_changeset_detach_node(struct of_changeset *ocs,
1371 		struct device_node *np)
1372 {
1373 	return of_changeset_action(ocs, OF_RECONFIG_DETACH_NODE, np, NULL);
1374 }
1375 
1376 static inline int of_changeset_add_property(struct of_changeset *ocs,
1377 		struct device_node *np, struct property *prop)
1378 {
1379 	return of_changeset_action(ocs, OF_RECONFIG_ADD_PROPERTY, np, prop);
1380 }
1381 
1382 static inline int of_changeset_remove_property(struct of_changeset *ocs,
1383 		struct device_node *np, struct property *prop)
1384 {
1385 	return of_changeset_action(ocs, OF_RECONFIG_REMOVE_PROPERTY, np, prop);
1386 }
1387 
1388 static inline int of_changeset_update_property(struct of_changeset *ocs,
1389 		struct device_node *np, struct property *prop)
1390 {
1391 	return of_changeset_action(ocs, OF_RECONFIG_UPDATE_PROPERTY, np, prop);
1392 }
1393 #else /* CONFIG_OF_DYNAMIC */
1394 static inline int of_reconfig_notifier_register(struct notifier_block *nb)
1395 {
1396 	return -EINVAL;
1397 }
1398 static inline int of_reconfig_notifier_unregister(struct notifier_block *nb)
1399 {
1400 	return -EINVAL;
1401 }
1402 static inline int of_reconfig_notify(unsigned long action,
1403 				     struct of_reconfig_data *arg)
1404 {
1405 	return -EINVAL;
1406 }
1407 static inline int of_reconfig_get_state_change(unsigned long action,
1408 						struct of_reconfig_data *arg)
1409 {
1410 	return -EINVAL;
1411 }
1412 #endif /* CONFIG_OF_DYNAMIC */
1413 
1414 /**
1415  * of_device_is_system_power_controller - Tells if system-power-controller is found for device_node
1416  * @np: Pointer to the given device_node
1417  *
1418  * return true if present false otherwise
1419  */
1420 static inline bool of_device_is_system_power_controller(const struct device_node *np)
1421 {
1422 	return of_property_read_bool(np, "system-power-controller");
1423 }
1424 
1425 /**
1426  * Overlay support
1427  */
1428 
1429 enum of_overlay_notify_action {
1430 	OF_OVERLAY_PRE_APPLY = 0,
1431 	OF_OVERLAY_POST_APPLY,
1432 	OF_OVERLAY_PRE_REMOVE,
1433 	OF_OVERLAY_POST_REMOVE,
1434 };
1435 
1436 struct of_overlay_notify_data {
1437 	struct device_node *overlay;
1438 	struct device_node *target;
1439 };
1440 
1441 #ifdef CONFIG_OF_OVERLAY
1442 
1443 int of_overlay_fdt_apply(const void *overlay_fdt, u32 overlay_fdt_size,
1444 			 int *ovcs_id);
1445 int of_overlay_remove(int *ovcs_id);
1446 int of_overlay_remove_all(void);
1447 
1448 int of_overlay_notifier_register(struct notifier_block *nb);
1449 int of_overlay_notifier_unregister(struct notifier_block *nb);
1450 
1451 #else
1452 
1453 static inline int of_overlay_fdt_apply(void *overlay_fdt, int *ovcs_id)
1454 {
1455 	return -ENOTSUPP;
1456 }
1457 
1458 static inline int of_overlay_remove(int *ovcs_id)
1459 {
1460 	return -ENOTSUPP;
1461 }
1462 
1463 static inline int of_overlay_remove_all(void)
1464 {
1465 	return -ENOTSUPP;
1466 }
1467 
1468 static inline int of_overlay_notifier_register(struct notifier_block *nb)
1469 {
1470 	return 0;
1471 }
1472 
1473 static inline int of_overlay_notifier_unregister(struct notifier_block *nb)
1474 {
1475 	return 0;
1476 }
1477 
1478 #endif
1479 
1480 #endif /* _LINUX_OF_H */
1481