xref: /linux-6.15/include/linux/of.h (revision 2ff40400)
1 #ifndef _LINUX_OF_H
2 #define _LINUX_OF_H
3 /*
4  * Definitions for talking to the Open Firmware PROM on
5  * Power Macintosh and other computers.
6  *
7  * Copyright (C) 1996-2005 Paul Mackerras.
8  *
9  * Updates for PPC64 by Peter Bergner & David Engebretsen, IBM Corp.
10  * Updates for SPARC64 by David S. Miller
11  * Derived from PowerPC and Sparc prom.h files by Stephen Rothwell, IBM Corp.
12  *
13  * This program is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU General Public License
15  * as published by the Free Software Foundation; either version
16  * 2 of the License, or (at your option) any later version.
17  */
18 #include <linux/types.h>
19 #include <linux/bitops.h>
20 #include <linux/errno.h>
21 #include <linux/kobject.h>
22 #include <linux/mod_devicetable.h>
23 #include <linux/spinlock.h>
24 #include <linux/topology.h>
25 #include <linux/notifier.h>
26 
27 #include <asm/byteorder.h>
28 #include <asm/errno.h>
29 
30 typedef u32 phandle;
31 typedef u32 ihandle;
32 
33 struct property {
34 	char	*name;
35 	int	length;
36 	void	*value;
37 	struct property *next;
38 	unsigned long _flags;
39 	unsigned int unique_id;
40 	struct bin_attribute attr;
41 };
42 
43 #if defined(CONFIG_SPARC)
44 struct of_irq_controller;
45 #endif
46 
47 struct device_node {
48 	const char *name;
49 	const char *type;
50 	phandle phandle;
51 	const char *full_name;
52 
53 	struct	property *properties;
54 	struct	property *deadprops;	/* removed properties */
55 	struct	device_node *parent;
56 	struct	device_node *child;
57 	struct	device_node *sibling;
58 	struct	device_node *next;	/* next device of same type */
59 	struct	device_node *allnext;	/* next in list of all nodes */
60 	struct	kobject kobj;
61 	unsigned long _flags;
62 	void	*data;
63 #if defined(CONFIG_SPARC)
64 	const char *path_component_name;
65 	unsigned int unique_id;
66 	struct of_irq_controller *irq_trans;
67 #endif
68 };
69 
70 #define MAX_PHANDLE_ARGS 16
71 struct of_phandle_args {
72 	struct device_node *np;
73 	int args_count;
74 	uint32_t args[MAX_PHANDLE_ARGS];
75 };
76 
77 /* initialize a node */
78 extern struct kobj_type of_node_ktype;
79 static inline void of_node_init(struct device_node *node)
80 {
81 	kobject_init(&node->kobj, &of_node_ktype);
82 }
83 
84 /* true when node is initialized */
85 static inline int of_node_is_initialized(struct device_node *node)
86 {
87 	return node && node->kobj.state_initialized;
88 }
89 
90 /* true when node is attached (i.e. present on sysfs) */
91 static inline int of_node_is_attached(struct device_node *node)
92 {
93 	return node && node->kobj.state_in_sysfs;
94 }
95 
96 #ifdef CONFIG_OF_DYNAMIC
97 extern struct device_node *of_node_get(struct device_node *node);
98 extern void of_node_put(struct device_node *node);
99 #else /* CONFIG_OF_DYNAMIC */
100 /* Dummy ref counting routines - to be implemented later */
101 static inline struct device_node *of_node_get(struct device_node *node)
102 {
103 	return node;
104 }
105 static inline void of_node_put(struct device_node *node) { }
106 #endif /* !CONFIG_OF_DYNAMIC */
107 
108 #ifdef CONFIG_OF
109 
110 /* Pointer for first entry in chain of all nodes. */
111 extern struct device_node *of_allnodes;
112 extern struct device_node *of_chosen;
113 extern struct device_node *of_aliases;
114 extern struct device_node *of_stdout;
115 extern raw_spinlock_t devtree_lock;
116 
117 static inline bool of_have_populated_dt(void)
118 {
119 	return of_allnodes != NULL;
120 }
121 
122 static inline bool of_node_is_root(const struct device_node *node)
123 {
124 	return node && (node->parent == NULL);
125 }
126 
127 static inline int of_node_check_flag(struct device_node *n, unsigned long flag)
128 {
129 	return test_bit(flag, &n->_flags);
130 }
131 
132 static inline int of_node_test_and_set_flag(struct device_node *n,
133 					    unsigned long flag)
134 {
135 	return test_and_set_bit(flag, &n->_flags);
136 }
137 
138 static inline void of_node_set_flag(struct device_node *n, unsigned long flag)
139 {
140 	set_bit(flag, &n->_flags);
141 }
142 
143 static inline void of_node_clear_flag(struct device_node *n, unsigned long flag)
144 {
145 	clear_bit(flag, &n->_flags);
146 }
147 
148 static inline int of_property_check_flag(struct property *p, unsigned long flag)
149 {
150 	return test_bit(flag, &p->_flags);
151 }
152 
153 static inline void of_property_set_flag(struct property *p, unsigned long flag)
154 {
155 	set_bit(flag, &p->_flags);
156 }
157 
158 static inline void of_property_clear_flag(struct property *p, unsigned long flag)
159 {
160 	clear_bit(flag, &p->_flags);
161 }
162 
163 extern struct device_node *of_find_all_nodes(struct device_node *prev);
164 
165 /*
166  * OF address retrieval & translation
167  */
168 
169 /* Helper to read a big number; size is in cells (not bytes) */
170 static inline u64 of_read_number(const __be32 *cell, int size)
171 {
172 	u64 r = 0;
173 	while (size--)
174 		r = (r << 32) | be32_to_cpu(*(cell++));
175 	return r;
176 }
177 
178 /* Like of_read_number, but we want an unsigned long result */
179 static inline unsigned long of_read_ulong(const __be32 *cell, int size)
180 {
181 	/* toss away upper bits if unsigned long is smaller than u64 */
182 	return of_read_number(cell, size);
183 }
184 
185 #if defined(CONFIG_SPARC)
186 #include <asm/prom.h>
187 #endif
188 
189 /* Default #address and #size cells.  Allow arch asm/prom.h to override */
190 #if !defined(OF_ROOT_NODE_ADDR_CELLS_DEFAULT)
191 #define OF_ROOT_NODE_ADDR_CELLS_DEFAULT 1
192 #define OF_ROOT_NODE_SIZE_CELLS_DEFAULT 1
193 #endif
194 
195 /* Default string compare functions, Allow arch asm/prom.h to override */
196 #if !defined(of_compat_cmp)
197 #define of_compat_cmp(s1, s2, l)	strcasecmp((s1), (s2))
198 #define of_prop_cmp(s1, s2)		strcmp((s1), (s2))
199 #define of_node_cmp(s1, s2)		strcasecmp((s1), (s2))
200 #endif
201 
202 /* flag descriptions */
203 #define OF_DYNAMIC	1 /* node and properties were allocated via kmalloc */
204 #define OF_DETACHED	2 /* node has been detached from the device tree */
205 #define OF_POPULATED	3 /* device already created for the node */
206 #define OF_POPULATED_BUS	4 /* of_platform_populate recursed to children of this node */
207 
208 #define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags)
209 #define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags)
210 
211 #define OF_BAD_ADDR	((u64)-1)
212 
213 static inline const char *of_node_full_name(const struct device_node *np)
214 {
215 	return np ? np->full_name : "<no-node>";
216 }
217 
218 #define for_each_of_allnodes(dn) \
219 	for (dn = of_allnodes; dn; dn = dn->allnext)
220 extern struct device_node *of_find_node_by_name(struct device_node *from,
221 	const char *name);
222 extern struct device_node *of_find_node_by_type(struct device_node *from,
223 	const char *type);
224 extern struct device_node *of_find_compatible_node(struct device_node *from,
225 	const char *type, const char *compat);
226 extern struct device_node *of_find_matching_node_and_match(
227 	struct device_node *from,
228 	const struct of_device_id *matches,
229 	const struct of_device_id **match);
230 
231 extern struct device_node *of_find_node_by_path(const char *path);
232 extern struct device_node *of_find_node_by_phandle(phandle handle);
233 extern struct device_node *of_get_parent(const struct device_node *node);
234 extern struct device_node *of_get_next_parent(struct device_node *node);
235 extern struct device_node *of_get_next_child(const struct device_node *node,
236 					     struct device_node *prev);
237 extern struct device_node *of_get_next_available_child(
238 	const struct device_node *node, struct device_node *prev);
239 
240 extern struct device_node *of_get_child_by_name(const struct device_node *node,
241 					const char *name);
242 
243 /* cache lookup */
244 extern struct device_node *of_find_next_cache_node(const struct device_node *);
245 extern struct device_node *of_find_node_with_property(
246 	struct device_node *from, const char *prop_name);
247 
248 extern struct property *of_find_property(const struct device_node *np,
249 					 const char *name,
250 					 int *lenp);
251 extern int of_property_count_elems_of_size(const struct device_node *np,
252 				const char *propname, int elem_size);
253 extern int of_property_read_u32_index(const struct device_node *np,
254 				       const char *propname,
255 				       u32 index, u32 *out_value);
256 extern int of_property_read_u8_array(const struct device_node *np,
257 			const char *propname, u8 *out_values, size_t sz);
258 extern int of_property_read_u16_array(const struct device_node *np,
259 			const char *propname, u16 *out_values, size_t sz);
260 extern int of_property_read_u32_array(const struct device_node *np,
261 				      const char *propname,
262 				      u32 *out_values,
263 				      size_t sz);
264 extern int of_property_read_u64(const struct device_node *np,
265 				const char *propname, u64 *out_value);
266 
267 extern int of_property_read_string(struct device_node *np,
268 				   const char *propname,
269 				   const char **out_string);
270 extern int of_property_match_string(struct device_node *np,
271 				    const char *propname,
272 				    const char *string);
273 extern int of_property_read_string_helper(struct device_node *np,
274 					      const char *propname,
275 					      const char **out_strs, size_t sz, int index);
276 extern int of_device_is_compatible(const struct device_node *device,
277 				   const char *);
278 extern int of_device_is_available(const struct device_node *device);
279 extern const void *of_get_property(const struct device_node *node,
280 				const char *name,
281 				int *lenp);
282 extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread);
283 #define for_each_property_of_node(dn, pp) \
284 	for (pp = dn->properties; pp != NULL; pp = pp->next)
285 
286 extern int of_n_addr_cells(struct device_node *np);
287 extern int of_n_size_cells(struct device_node *np);
288 extern const struct of_device_id *of_match_node(
289 	const struct of_device_id *matches, const struct device_node *node);
290 extern int of_modalias_node(struct device_node *node, char *modalias, int len);
291 extern void of_print_phandle_args(const char *msg, const struct of_phandle_args *args);
292 extern struct device_node *of_parse_phandle(const struct device_node *np,
293 					    const char *phandle_name,
294 					    int index);
295 extern int of_parse_phandle_with_args(const struct device_node *np,
296 	const char *list_name, const char *cells_name, int index,
297 	struct of_phandle_args *out_args);
298 extern int of_parse_phandle_with_fixed_args(const struct device_node *np,
299 	const char *list_name, int cells_count, int index,
300 	struct of_phandle_args *out_args);
301 extern int of_count_phandle_with_args(const struct device_node *np,
302 	const char *list_name, const char *cells_name);
303 
304 extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align));
305 extern int of_alias_get_id(struct device_node *np, const char *stem);
306 
307 extern int of_machine_is_compatible(const char *compat);
308 
309 extern int of_add_property(struct device_node *np, struct property *prop);
310 extern int of_remove_property(struct device_node *np, struct property *prop);
311 extern int of_update_property(struct device_node *np, struct property *newprop);
312 
313 /* For updating the device tree at runtime */
314 #define OF_RECONFIG_ATTACH_NODE		0x0001
315 #define OF_RECONFIG_DETACH_NODE		0x0002
316 #define OF_RECONFIG_ADD_PROPERTY	0x0003
317 #define OF_RECONFIG_REMOVE_PROPERTY	0x0004
318 #define OF_RECONFIG_UPDATE_PROPERTY	0x0005
319 
320 struct of_prop_reconfig {
321 	struct device_node	*dn;
322 	struct property		*prop;
323 	struct property		*old_prop;
324 };
325 
326 extern int of_reconfig_notifier_register(struct notifier_block *);
327 extern int of_reconfig_notifier_unregister(struct notifier_block *);
328 extern int of_reconfig_notify(unsigned long, void *);
329 
330 extern int of_attach_node(struct device_node *);
331 extern int of_detach_node(struct device_node *);
332 
333 #define of_match_ptr(_ptr)	(_ptr)
334 
335 /*
336  * struct property *prop;
337  * const __be32 *p;
338  * u32 u;
339  *
340  * of_property_for_each_u32(np, "propname", prop, p, u)
341  *         printk("U32 value: %x\n", u);
342  */
343 const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
344 			       u32 *pu);
345 /*
346  * struct property *prop;
347  * const char *s;
348  *
349  * of_property_for_each_string(np, "propname", prop, s)
350  *         printk("String value: %s\n", s);
351  */
352 const char *of_prop_next_string(struct property *prop, const char *cur);
353 
354 bool of_console_check(struct device_node *dn, char *name, int index);
355 
356 #else /* CONFIG_OF */
357 
358 static inline const char* of_node_full_name(const struct device_node *np)
359 {
360 	return "<no-node>";
361 }
362 
363 static inline struct device_node *of_find_node_by_name(struct device_node *from,
364 	const char *name)
365 {
366 	return NULL;
367 }
368 
369 static inline struct device_node *of_find_node_by_type(struct device_node *from,
370 	const char *type)
371 {
372 	return NULL;
373 }
374 
375 static inline struct device_node *of_find_matching_node_and_match(
376 	struct device_node *from,
377 	const struct of_device_id *matches,
378 	const struct of_device_id **match)
379 {
380 	return NULL;
381 }
382 
383 static inline struct device_node *of_find_node_by_path(const char *path)
384 {
385 	return NULL;
386 }
387 
388 static inline struct device_node *of_get_parent(const struct device_node *node)
389 {
390 	return NULL;
391 }
392 
393 static inline struct device_node *of_get_next_child(
394 	const struct device_node *node, struct device_node *prev)
395 {
396 	return NULL;
397 }
398 
399 static inline struct device_node *of_get_next_available_child(
400 	const struct device_node *node, struct device_node *prev)
401 {
402 	return NULL;
403 }
404 
405 static inline struct device_node *of_find_node_with_property(
406 	struct device_node *from, const char *prop_name)
407 {
408 	return NULL;
409 }
410 
411 static inline bool of_have_populated_dt(void)
412 {
413 	return false;
414 }
415 
416 static inline struct device_node *of_get_child_by_name(
417 					const struct device_node *node,
418 					const char *name)
419 {
420 	return NULL;
421 }
422 
423 static inline int of_device_is_compatible(const struct device_node *device,
424 					  const char *name)
425 {
426 	return 0;
427 }
428 
429 static inline int of_device_is_available(const struct device_node *device)
430 {
431 	return 0;
432 }
433 
434 static inline struct property *of_find_property(const struct device_node *np,
435 						const char *name,
436 						int *lenp)
437 {
438 	return NULL;
439 }
440 
441 static inline struct device_node *of_find_compatible_node(
442 						struct device_node *from,
443 						const char *type,
444 						const char *compat)
445 {
446 	return NULL;
447 }
448 
449 static inline int of_property_count_elems_of_size(const struct device_node *np,
450 			const char *propname, int elem_size)
451 {
452 	return -ENOSYS;
453 }
454 
455 static inline int of_property_read_u32_index(const struct device_node *np,
456 			const char *propname, u32 index, u32 *out_value)
457 {
458 	return -ENOSYS;
459 }
460 
461 static inline int of_property_read_u8_array(const struct device_node *np,
462 			const char *propname, u8 *out_values, size_t sz)
463 {
464 	return -ENOSYS;
465 }
466 
467 static inline int of_property_read_u16_array(const struct device_node *np,
468 			const char *propname, u16 *out_values, size_t sz)
469 {
470 	return -ENOSYS;
471 }
472 
473 static inline int of_property_read_u32_array(const struct device_node *np,
474 					     const char *propname,
475 					     u32 *out_values, size_t sz)
476 {
477 	return -ENOSYS;
478 }
479 
480 static inline int of_property_read_string(struct device_node *np,
481 					  const char *propname,
482 					  const char **out_string)
483 {
484 	return -ENOSYS;
485 }
486 
487 static inline int of_property_read_string_helper(struct device_node *np,
488 						 const char *propname,
489 						 const char **out_strs, size_t sz, int index)
490 {
491 	return -ENOSYS;
492 }
493 
494 static inline const void *of_get_property(const struct device_node *node,
495 				const char *name,
496 				int *lenp)
497 {
498 	return NULL;
499 }
500 
501 static inline struct device_node *of_get_cpu_node(int cpu,
502 					unsigned int *thread)
503 {
504 	return NULL;
505 }
506 
507 static inline int of_property_read_u64(const struct device_node *np,
508 				       const char *propname, u64 *out_value)
509 {
510 	return -ENOSYS;
511 }
512 
513 static inline int of_property_match_string(struct device_node *np,
514 					   const char *propname,
515 					   const char *string)
516 {
517 	return -ENOSYS;
518 }
519 
520 static inline struct device_node *of_parse_phandle(const struct device_node *np,
521 						   const char *phandle_name,
522 						   int index)
523 {
524 	return NULL;
525 }
526 
527 static inline int of_parse_phandle_with_args(struct device_node *np,
528 					     const char *list_name,
529 					     const char *cells_name,
530 					     int index,
531 					     struct of_phandle_args *out_args)
532 {
533 	return -ENOSYS;
534 }
535 
536 static inline int of_parse_phandle_with_fixed_args(const struct device_node *np,
537 	const char *list_name, int cells_count, int index,
538 	struct of_phandle_args *out_args)
539 {
540 	return -ENOSYS;
541 }
542 
543 static inline int of_count_phandle_with_args(struct device_node *np,
544 					     const char *list_name,
545 					     const char *cells_name)
546 {
547 	return -ENOSYS;
548 }
549 
550 static inline int of_alias_get_id(struct device_node *np, const char *stem)
551 {
552 	return -ENOSYS;
553 }
554 
555 static inline int of_machine_is_compatible(const char *compat)
556 {
557 	return 0;
558 }
559 
560 static inline bool of_console_check(const struct device_node *dn, const char *name, int index)
561 {
562 	return false;
563 }
564 
565 static inline const __be32 *of_prop_next_u32(struct property *prop,
566 		const __be32 *cur, u32 *pu)
567 {
568 	return NULL;
569 }
570 
571 static inline const char *of_prop_next_string(struct property *prop,
572 		const char *cur)
573 {
574 	return NULL;
575 }
576 
577 #define of_match_ptr(_ptr)	NULL
578 #define of_match_node(_matches, _node)	NULL
579 #endif /* CONFIG_OF */
580 
581 #if defined(CONFIG_OF) && defined(CONFIG_NUMA)
582 extern int of_node_to_nid(struct device_node *np);
583 #else
584 static inline int of_node_to_nid(struct device_node *device) { return 0; }
585 #endif
586 
587 static inline struct device_node *of_find_matching_node(
588 	struct device_node *from,
589 	const struct of_device_id *matches)
590 {
591 	return of_find_matching_node_and_match(from, matches, NULL);
592 }
593 
594 /**
595  * of_property_count_u8_elems - Count the number of u8 elements in a property
596  *
597  * @np:		device node from which the property value is to be read.
598  * @propname:	name of the property to be searched.
599  *
600  * Search for a property in a device node and count the number of u8 elements
601  * in it. Returns number of elements on sucess, -EINVAL if the property does
602  * not exist or its length does not match a multiple of u8 and -ENODATA if the
603  * property does not have a value.
604  */
605 static inline int of_property_count_u8_elems(const struct device_node *np,
606 				const char *propname)
607 {
608 	return of_property_count_elems_of_size(np, propname, sizeof(u8));
609 }
610 
611 /**
612  * of_property_count_u16_elems - Count the number of u16 elements in a property
613  *
614  * @np:		device node from which the property value is to be read.
615  * @propname:	name of the property to be searched.
616  *
617  * Search for a property in a device node and count the number of u16 elements
618  * in it. Returns number of elements on sucess, -EINVAL if the property does
619  * not exist or its length does not match a multiple of u16 and -ENODATA if the
620  * property does not have a value.
621  */
622 static inline int of_property_count_u16_elems(const struct device_node *np,
623 				const char *propname)
624 {
625 	return of_property_count_elems_of_size(np, propname, sizeof(u16));
626 }
627 
628 /**
629  * of_property_count_u32_elems - Count the number of u32 elements in a property
630  *
631  * @np:		device node from which the property value is to be read.
632  * @propname:	name of the property to be searched.
633  *
634  * Search for a property in a device node and count the number of u32 elements
635  * in it. Returns number of elements on sucess, -EINVAL if the property does
636  * not exist or its length does not match a multiple of u32 and -ENODATA if the
637  * property does not have a value.
638  */
639 static inline int of_property_count_u32_elems(const struct device_node *np,
640 				const char *propname)
641 {
642 	return of_property_count_elems_of_size(np, propname, sizeof(u32));
643 }
644 
645 /**
646  * of_property_count_u64_elems - Count the number of u64 elements in a property
647  *
648  * @np:		device node from which the property value is to be read.
649  * @propname:	name of the property to be searched.
650  *
651  * Search for a property in a device node and count the number of u64 elements
652  * in it. Returns number of elements on sucess, -EINVAL if the property does
653  * not exist or its length does not match a multiple of u64 and -ENODATA if the
654  * property does not have a value.
655  */
656 static inline int of_property_count_u64_elems(const struct device_node *np,
657 				const char *propname)
658 {
659 	return of_property_count_elems_of_size(np, propname, sizeof(u64));
660 }
661 
662 /**
663  * of_property_read_string_array() - Read an array of strings from a multiple
664  * strings property.
665  * @np:		device node from which the property value is to be read.
666  * @propname:	name of the property to be searched.
667  * @out_strs:	output array of string pointers.
668  * @sz:		number of array elements to read.
669  *
670  * Search for a property in a device tree node and retrieve a list of
671  * terminated string values (pointer to data, not a copy) in that property.
672  *
673  * If @out_strs is NULL, the number of strings in the property is returned.
674  */
675 static inline int of_property_read_string_array(struct device_node *np,
676 						const char *propname, const char **out_strs,
677 						size_t sz)
678 {
679 	return of_property_read_string_helper(np, propname, out_strs, sz, 0);
680 }
681 
682 /**
683  * of_property_count_strings() - Find and return the number of strings from a
684  * multiple strings property.
685  * @np:		device node from which the property value is to be read.
686  * @propname:	name of the property to be searched.
687  *
688  * Search for a property in a device tree node and retrieve the number of null
689  * terminated string contain in it. Returns the number of strings on
690  * success, -EINVAL if the property does not exist, -ENODATA if property
691  * does not have a value, and -EILSEQ if the string is not null-terminated
692  * within the length of the property data.
693  */
694 static inline int of_property_count_strings(struct device_node *np,
695 					    const char *propname)
696 {
697 	return of_property_read_string_helper(np, propname, NULL, 0, 0);
698 }
699 
700 /**
701  * of_property_read_string_index() - Find and read a string from a multiple
702  * strings property.
703  * @np:		device node from which the property value is to be read.
704  * @propname:	name of the property to be searched.
705  * @index:	index of the string in the list of strings
706  * @out_string:	pointer to null terminated return string, modified only if
707  *		return value is 0.
708  *
709  * Search for a property in a device tree node and retrieve a null
710  * terminated string value (pointer to data, not a copy) in the list of strings
711  * contained in that property.
712  * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
713  * property does not have a value, and -EILSEQ if the string is not
714  * null-terminated within the length of the property data.
715  *
716  * The out_string pointer is modified only if a valid string can be decoded.
717  */
718 static inline int of_property_read_string_index(struct device_node *np,
719 						const char *propname,
720 						int index, const char **output)
721 {
722 	int rc = of_property_read_string_helper(np, propname, output, 1, index);
723 	return rc < 0 ? rc : 0;
724 }
725 
726 /**
727  * of_property_read_bool - Findfrom a property
728  * @np:		device node from which the property value is to be read.
729  * @propname:	name of the property to be searched.
730  *
731  * Search for a property in a device node.
732  * Returns true if the property exist false otherwise.
733  */
734 static inline bool of_property_read_bool(const struct device_node *np,
735 					 const char *propname)
736 {
737 	struct property *prop = of_find_property(np, propname, NULL);
738 
739 	return prop ? true : false;
740 }
741 
742 static inline int of_property_read_u8(const struct device_node *np,
743 				       const char *propname,
744 				       u8 *out_value)
745 {
746 	return of_property_read_u8_array(np, propname, out_value, 1);
747 }
748 
749 static inline int of_property_read_u16(const struct device_node *np,
750 				       const char *propname,
751 				       u16 *out_value)
752 {
753 	return of_property_read_u16_array(np, propname, out_value, 1);
754 }
755 
756 static inline int of_property_read_u32(const struct device_node *np,
757 				       const char *propname,
758 				       u32 *out_value)
759 {
760 	return of_property_read_u32_array(np, propname, out_value, 1);
761 }
762 
763 #define of_property_for_each_u32(np, propname, prop, p, u)	\
764 	for (prop = of_find_property(np, propname, NULL),	\
765 		p = of_prop_next_u32(prop, NULL, &u);		\
766 		p;						\
767 		p = of_prop_next_u32(prop, p, &u))
768 
769 #define of_property_for_each_string(np, propname, prop, s)	\
770 	for (prop = of_find_property(np, propname, NULL),	\
771 		s = of_prop_next_string(prop, NULL);		\
772 		s;						\
773 		s = of_prop_next_string(prop, s))
774 
775 #define for_each_node_by_name(dn, name) \
776 	for (dn = of_find_node_by_name(NULL, name); dn; \
777 	     dn = of_find_node_by_name(dn, name))
778 #define for_each_node_by_type(dn, type) \
779 	for (dn = of_find_node_by_type(NULL, type); dn; \
780 	     dn = of_find_node_by_type(dn, type))
781 #define for_each_compatible_node(dn, type, compatible) \
782 	for (dn = of_find_compatible_node(NULL, type, compatible); dn; \
783 	     dn = of_find_compatible_node(dn, type, compatible))
784 #define for_each_matching_node(dn, matches) \
785 	for (dn = of_find_matching_node(NULL, matches); dn; \
786 	     dn = of_find_matching_node(dn, matches))
787 #define for_each_matching_node_and_match(dn, matches, match) \
788 	for (dn = of_find_matching_node_and_match(NULL, matches, match); \
789 	     dn; dn = of_find_matching_node_and_match(dn, matches, match))
790 
791 #define for_each_child_of_node(parent, child) \
792 	for (child = of_get_next_child(parent, NULL); child != NULL; \
793 	     child = of_get_next_child(parent, child))
794 #define for_each_available_child_of_node(parent, child) \
795 	for (child = of_get_next_available_child(parent, NULL); child != NULL; \
796 	     child = of_get_next_available_child(parent, child))
797 
798 #define for_each_node_with_property(dn, prop_name) \
799 	for (dn = of_find_node_with_property(NULL, prop_name); dn; \
800 	     dn = of_find_node_with_property(dn, prop_name))
801 
802 static inline int of_get_child_count(const struct device_node *np)
803 {
804 	struct device_node *child;
805 	int num = 0;
806 
807 	for_each_child_of_node(np, child)
808 		num++;
809 
810 	return num;
811 }
812 
813 static inline int of_get_available_child_count(const struct device_node *np)
814 {
815 	struct device_node *child;
816 	int num = 0;
817 
818 	for_each_available_child_of_node(np, child)
819 		num++;
820 
821 	return num;
822 }
823 
824 #ifdef CONFIG_OF
825 #define _OF_DECLARE(table, name, compat, fn, fn_type)			\
826 	static const struct of_device_id __of_table_##name		\
827 		__used __section(__##table##_of_table)			\
828 		 = { .compatible = compat,				\
829 		     .data = (fn == (fn_type)NULL) ? fn : fn  }
830 #else
831 #define _OF_DECLARE(table, name, compat, fn, fn_type)					\
832 	static const struct of_device_id __of_table_##name		\
833 		__attribute__((unused))					\
834 		 = { .compatible = compat,				\
835 		     .data = (fn == (fn_type)NULL) ? fn : fn }
836 #endif
837 
838 typedef int (*of_init_fn_2)(struct device_node *, struct device_node *);
839 typedef void (*of_init_fn_1)(struct device_node *);
840 
841 #define OF_DECLARE_1(table, name, compat, fn) \
842 		_OF_DECLARE(table, name, compat, fn, of_init_fn_1)
843 #define OF_DECLARE_2(table, name, compat, fn) \
844 		_OF_DECLARE(table, name, compat, fn, of_init_fn_2)
845 
846 /**
847  * struct of_changeset_entry	- Holds a changeset entry
848  *
849  * @node:	list_head for the log list
850  * @action:	notifier action
851  * @np:		pointer to the device node affected
852  * @prop:	pointer to the property affected
853  * @old_prop:	hold a pointer to the original property
854  *
855  * Every modification of the device tree during a changeset
856  * is held in a list of of_changeset_entry structures.
857  * That way we can recover from a partial application, or we can
858  * revert the changeset
859  */
860 struct of_changeset_entry {
861 	struct list_head node;
862 	unsigned long action;
863 	struct device_node *np;
864 	struct property *prop;
865 	struct property *old_prop;
866 };
867 
868 /**
869  * struct of_changeset - changeset tracker structure
870  *
871  * @entries:	list_head for the changeset entries
872  *
873  * changesets are a convenient way to apply bulk changes to the
874  * live tree. In case of an error, changes are rolled-back.
875  * changesets live on after initial application, and if not
876  * destroyed after use, they can be reverted in one single call.
877  */
878 struct of_changeset {
879 	struct list_head entries;
880 };
881 
882 #ifdef CONFIG_OF_DYNAMIC
883 extern void of_changeset_init(struct of_changeset *ocs);
884 extern void of_changeset_destroy(struct of_changeset *ocs);
885 extern int of_changeset_apply(struct of_changeset *ocs);
886 extern int of_changeset_revert(struct of_changeset *ocs);
887 extern int of_changeset_action(struct of_changeset *ocs,
888 		unsigned long action, struct device_node *np,
889 		struct property *prop);
890 
891 static inline int of_changeset_attach_node(struct of_changeset *ocs,
892 		struct device_node *np)
893 {
894 	return of_changeset_action(ocs, OF_RECONFIG_ATTACH_NODE, np, NULL);
895 }
896 
897 static inline int of_changeset_detach_node(struct of_changeset *ocs,
898 		struct device_node *np)
899 {
900 	return of_changeset_action(ocs, OF_RECONFIG_DETACH_NODE, np, NULL);
901 }
902 
903 static inline int of_changeset_add_property(struct of_changeset *ocs,
904 		struct device_node *np, struct property *prop)
905 {
906 	return of_changeset_action(ocs, OF_RECONFIG_ADD_PROPERTY, np, prop);
907 }
908 
909 static inline int of_changeset_remove_property(struct of_changeset *ocs,
910 		struct device_node *np, struct property *prop)
911 {
912 	return of_changeset_action(ocs, OF_RECONFIG_REMOVE_PROPERTY, np, prop);
913 }
914 
915 static inline int of_changeset_update_property(struct of_changeset *ocs,
916 		struct device_node *np, struct property *prop)
917 {
918 	return of_changeset_action(ocs, OF_RECONFIG_UPDATE_PROPERTY, np, prop);
919 }
920 #endif
921 
922 /* CONFIG_OF_RESOLVE api */
923 extern int of_resolve_phandles(struct device_node *tree);
924 
925 #endif /* _LINUX_OF_H */
926