xref: /linux-6.15/include/linux/of.h (revision 81f0cd97)
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 #include <linux/property.h>
27 #include <linux/list.h>
28 
29 #include <asm/byteorder.h>
30 #include <asm/errno.h>
31 
32 typedef u32 phandle;
33 typedef u32 ihandle;
34 
35 struct property {
36 	char	*name;
37 	int	length;
38 	void	*value;
39 	struct property *next;
40 	unsigned long _flags;
41 	unsigned int unique_id;
42 	struct bin_attribute attr;
43 };
44 
45 #if defined(CONFIG_SPARC)
46 struct of_irq_controller;
47 #endif
48 
49 struct device_node {
50 	const char *name;
51 	const char *type;
52 	phandle phandle;
53 	const char *full_name;
54 	struct fwnode_handle fwnode;
55 
56 	struct	property *properties;
57 	struct	property *deadprops;	/* removed properties */
58 	struct	device_node *parent;
59 	struct	device_node *child;
60 	struct	device_node *sibling;
61 	struct	kobject kobj;
62 	unsigned long _flags;
63 	void	*data;
64 #if defined(CONFIG_SPARC)
65 	const char *path_component_name;
66 	unsigned int unique_id;
67 	struct of_irq_controller *irq_trans;
68 #endif
69 };
70 
71 #define MAX_PHANDLE_ARGS 16
72 struct of_phandle_args {
73 	struct device_node *np;
74 	int args_count;
75 	uint32_t args[MAX_PHANDLE_ARGS];
76 };
77 
78 struct of_reconfig_data {
79 	struct device_node	*dn;
80 	struct property		*prop;
81 	struct property		*old_prop;
82 };
83 
84 /* initialize a node */
85 extern struct kobj_type of_node_ktype;
86 static inline void of_node_init(struct device_node *node)
87 {
88 	kobject_init(&node->kobj, &of_node_ktype);
89 	node->fwnode.type = FWNODE_OF;
90 }
91 
92 /* true when node is initialized */
93 static inline int of_node_is_initialized(struct device_node *node)
94 {
95 	return node && node->kobj.state_initialized;
96 }
97 
98 /* true when node is attached (i.e. present on sysfs) */
99 static inline int of_node_is_attached(struct device_node *node)
100 {
101 	return node && node->kobj.state_in_sysfs;
102 }
103 
104 #ifdef CONFIG_OF_DYNAMIC
105 extern struct device_node *of_node_get(struct device_node *node);
106 extern void of_node_put(struct device_node *node);
107 #else /* CONFIG_OF_DYNAMIC */
108 /* Dummy ref counting routines - to be implemented later */
109 static inline struct device_node *of_node_get(struct device_node *node)
110 {
111 	return node;
112 }
113 static inline void of_node_put(struct device_node *node) { }
114 #endif /* !CONFIG_OF_DYNAMIC */
115 
116 /* Pointer for first entry in chain of all nodes. */
117 extern struct device_node *of_root;
118 extern struct device_node *of_chosen;
119 extern struct device_node *of_aliases;
120 extern struct device_node *of_stdout;
121 extern raw_spinlock_t devtree_lock;
122 
123 #ifdef CONFIG_OF
124 static inline bool is_of_node(struct fwnode_handle *fwnode)
125 {
126 	return fwnode && fwnode->type == FWNODE_OF;
127 }
128 
129 static inline struct device_node *of_node(struct fwnode_handle *fwnode)
130 {
131 	return fwnode ? container_of(fwnode, struct device_node, fwnode) : NULL;
132 }
133 
134 static inline bool of_have_populated_dt(void)
135 {
136 	return of_root != NULL;
137 }
138 
139 static inline bool of_node_is_root(const struct device_node *node)
140 {
141 	return node && (node->parent == NULL);
142 }
143 
144 static inline int of_node_check_flag(struct device_node *n, unsigned long flag)
145 {
146 	return test_bit(flag, &n->_flags);
147 }
148 
149 static inline int of_node_test_and_set_flag(struct device_node *n,
150 					    unsigned long flag)
151 {
152 	return test_and_set_bit(flag, &n->_flags);
153 }
154 
155 static inline void of_node_set_flag(struct device_node *n, unsigned long flag)
156 {
157 	set_bit(flag, &n->_flags);
158 }
159 
160 static inline void of_node_clear_flag(struct device_node *n, unsigned long flag)
161 {
162 	clear_bit(flag, &n->_flags);
163 }
164 
165 static inline int of_property_check_flag(struct property *p, unsigned long flag)
166 {
167 	return test_bit(flag, &p->_flags);
168 }
169 
170 static inline void of_property_set_flag(struct property *p, unsigned long flag)
171 {
172 	set_bit(flag, &p->_flags);
173 }
174 
175 static inline void of_property_clear_flag(struct property *p, unsigned long flag)
176 {
177 	clear_bit(flag, &p->_flags);
178 }
179 
180 extern struct device_node *__of_find_all_nodes(struct device_node *prev);
181 extern struct device_node *of_find_all_nodes(struct device_node *prev);
182 
183 /*
184  * OF address retrieval & translation
185  */
186 
187 /* Helper to read a big number; size is in cells (not bytes) */
188 static inline u64 of_read_number(const __be32 *cell, int size)
189 {
190 	u64 r = 0;
191 	while (size--)
192 		r = (r << 32) | be32_to_cpu(*(cell++));
193 	return r;
194 }
195 
196 /* Like of_read_number, but we want an unsigned long result */
197 static inline unsigned long of_read_ulong(const __be32 *cell, int size)
198 {
199 	/* toss away upper bits if unsigned long is smaller than u64 */
200 	return of_read_number(cell, size);
201 }
202 
203 #if defined(CONFIG_SPARC)
204 #include <asm/prom.h>
205 #endif
206 
207 /* Default #address and #size cells.  Allow arch asm/prom.h to override */
208 #if !defined(OF_ROOT_NODE_ADDR_CELLS_DEFAULT)
209 #define OF_ROOT_NODE_ADDR_CELLS_DEFAULT 1
210 #define OF_ROOT_NODE_SIZE_CELLS_DEFAULT 1
211 #endif
212 
213 /* Default string compare functions, Allow arch asm/prom.h to override */
214 #if !defined(of_compat_cmp)
215 #define of_compat_cmp(s1, s2, l)	strcasecmp((s1), (s2))
216 #define of_prop_cmp(s1, s2)		strcmp((s1), (s2))
217 #define of_node_cmp(s1, s2)		strcasecmp((s1), (s2))
218 #endif
219 
220 /* flag descriptions */
221 #define OF_DYNAMIC	1 /* node and properties were allocated via kmalloc */
222 #define OF_DETACHED	2 /* node has been detached from the device tree */
223 #define OF_POPULATED	3 /* device already created for the node */
224 #define OF_POPULATED_BUS	4 /* of_platform_populate recursed to children of this node */
225 
226 #define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags)
227 #define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags)
228 
229 #define OF_BAD_ADDR	((u64)-1)
230 
231 static inline const char *of_node_full_name(const struct device_node *np)
232 {
233 	return np ? np->full_name : "<no-node>";
234 }
235 
236 #define for_each_of_allnodes_from(from, dn) \
237 	for (dn = __of_find_all_nodes(from); dn; dn = __of_find_all_nodes(dn))
238 #define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn)
239 extern struct device_node *of_find_node_by_name(struct device_node *from,
240 	const char *name);
241 extern struct device_node *of_find_node_by_type(struct device_node *from,
242 	const char *type);
243 extern struct device_node *of_find_compatible_node(struct device_node *from,
244 	const char *type, const char *compat);
245 extern struct device_node *of_find_matching_node_and_match(
246 	struct device_node *from,
247 	const struct of_device_id *matches,
248 	const struct of_device_id **match);
249 
250 extern struct device_node *of_find_node_opts_by_path(const char *path,
251 	const char **opts);
252 static inline struct device_node *of_find_node_by_path(const char *path)
253 {
254 	return of_find_node_opts_by_path(path, NULL);
255 }
256 
257 extern struct device_node *of_find_node_by_phandle(phandle handle);
258 extern struct device_node *of_get_parent(const struct device_node *node);
259 extern struct device_node *of_get_next_parent(struct device_node *node);
260 extern struct device_node *of_get_next_child(const struct device_node *node,
261 					     struct device_node *prev);
262 extern struct device_node *of_get_next_available_child(
263 	const struct device_node *node, struct device_node *prev);
264 
265 extern struct device_node *of_get_child_by_name(const struct device_node *node,
266 					const char *name);
267 
268 /* cache lookup */
269 extern struct device_node *of_find_next_cache_node(const struct device_node *);
270 extern struct device_node *of_find_node_with_property(
271 	struct device_node *from, const char *prop_name);
272 
273 extern struct property *of_find_property(const struct device_node *np,
274 					 const char *name,
275 					 int *lenp);
276 extern int of_property_count_elems_of_size(const struct device_node *np,
277 				const char *propname, int elem_size);
278 extern int of_property_read_u32_index(const struct device_node *np,
279 				       const char *propname,
280 				       u32 index, u32 *out_value);
281 extern int of_property_read_u8_array(const struct device_node *np,
282 			const char *propname, u8 *out_values, size_t sz);
283 extern int of_property_read_u16_array(const struct device_node *np,
284 			const char *propname, u16 *out_values, size_t sz);
285 extern int of_property_read_u32_array(const struct device_node *np,
286 				      const char *propname,
287 				      u32 *out_values,
288 				      size_t sz);
289 extern int of_property_read_u64(const struct device_node *np,
290 				const char *propname, u64 *out_value);
291 extern int of_property_read_u64_array(const struct device_node *np,
292 				      const char *propname,
293 				      u64 *out_values,
294 				      size_t sz);
295 
296 extern int of_property_read_string(struct device_node *np,
297 				   const char *propname,
298 				   const char **out_string);
299 extern int of_property_match_string(struct device_node *np,
300 				    const char *propname,
301 				    const char *string);
302 extern int of_property_read_string_helper(struct device_node *np,
303 					      const char *propname,
304 					      const char **out_strs, size_t sz, int index);
305 extern int of_device_is_compatible(const struct device_node *device,
306 				   const char *);
307 extern bool of_device_is_available(const struct device_node *device);
308 extern const void *of_get_property(const struct device_node *node,
309 				const char *name,
310 				int *lenp);
311 extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread);
312 #define for_each_property_of_node(dn, pp) \
313 	for (pp = dn->properties; pp != NULL; pp = pp->next)
314 
315 extern int of_n_addr_cells(struct device_node *np);
316 extern int of_n_size_cells(struct device_node *np);
317 extern const struct of_device_id *of_match_node(
318 	const struct of_device_id *matches, const struct device_node *node);
319 extern int of_modalias_node(struct device_node *node, char *modalias, int len);
320 extern void of_print_phandle_args(const char *msg, const struct of_phandle_args *args);
321 extern struct device_node *of_parse_phandle(const struct device_node *np,
322 					    const char *phandle_name,
323 					    int index);
324 extern int of_parse_phandle_with_args(const struct device_node *np,
325 	const char *list_name, const char *cells_name, int index,
326 	struct of_phandle_args *out_args);
327 extern int of_parse_phandle_with_fixed_args(const struct device_node *np,
328 	const char *list_name, int cells_count, int index,
329 	struct of_phandle_args *out_args);
330 extern int of_count_phandle_with_args(const struct device_node *np,
331 	const char *list_name, const char *cells_name);
332 
333 extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align));
334 extern int of_alias_get_id(struct device_node *np, const char *stem);
335 extern int of_alias_get_highest_id(const char *stem);
336 
337 extern int of_machine_is_compatible(const char *compat);
338 
339 extern int of_add_property(struct device_node *np, struct property *prop);
340 extern int of_remove_property(struct device_node *np, struct property *prop);
341 extern int of_update_property(struct device_node *np, struct property *newprop);
342 
343 /* For updating the device tree at runtime */
344 #define OF_RECONFIG_ATTACH_NODE		0x0001
345 #define OF_RECONFIG_DETACH_NODE		0x0002
346 #define OF_RECONFIG_ADD_PROPERTY	0x0003
347 #define OF_RECONFIG_REMOVE_PROPERTY	0x0004
348 #define OF_RECONFIG_UPDATE_PROPERTY	0x0005
349 
350 extern int of_attach_node(struct device_node *);
351 extern int of_detach_node(struct device_node *);
352 
353 #define of_match_ptr(_ptr)	(_ptr)
354 
355 /*
356  * struct property *prop;
357  * const __be32 *p;
358  * u32 u;
359  *
360  * of_property_for_each_u32(np, "propname", prop, p, u)
361  *         printk("U32 value: %x\n", u);
362  */
363 const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
364 			       u32 *pu);
365 /*
366  * struct property *prop;
367  * const char *s;
368  *
369  * of_property_for_each_string(np, "propname", prop, s)
370  *         printk("String value: %s\n", s);
371  */
372 const char *of_prop_next_string(struct property *prop, const char *cur);
373 
374 bool of_console_check(struct device_node *dn, char *name, int index);
375 
376 #else /* CONFIG_OF */
377 
378 static inline bool is_of_node(struct fwnode_handle *fwnode)
379 {
380 	return false;
381 }
382 
383 static inline struct device_node *of_node(struct fwnode_handle *fwnode)
384 {
385 	return NULL;
386 }
387 
388 static inline const char* of_node_full_name(const struct device_node *np)
389 {
390 	return "<no-node>";
391 }
392 
393 static inline struct device_node *of_find_node_by_name(struct device_node *from,
394 	const char *name)
395 {
396 	return NULL;
397 }
398 
399 static inline struct device_node *of_find_node_by_type(struct device_node *from,
400 	const char *type)
401 {
402 	return NULL;
403 }
404 
405 static inline struct device_node *of_find_matching_node_and_match(
406 	struct device_node *from,
407 	const struct of_device_id *matches,
408 	const struct of_device_id **match)
409 {
410 	return NULL;
411 }
412 
413 static inline struct device_node *of_find_node_by_path(const char *path)
414 {
415 	return NULL;
416 }
417 
418 static inline struct device_node *of_find_node_opts_by_path(const char *path,
419 	const char **opts)
420 {
421 	return NULL;
422 }
423 
424 static inline struct device_node *of_get_parent(const struct device_node *node)
425 {
426 	return NULL;
427 }
428 
429 static inline struct device_node *of_get_next_child(
430 	const struct device_node *node, struct device_node *prev)
431 {
432 	return NULL;
433 }
434 
435 static inline struct device_node *of_get_next_available_child(
436 	const struct device_node *node, struct device_node *prev)
437 {
438 	return NULL;
439 }
440 
441 static inline struct device_node *of_find_node_with_property(
442 	struct device_node *from, const char *prop_name)
443 {
444 	return NULL;
445 }
446 
447 static inline bool of_have_populated_dt(void)
448 {
449 	return false;
450 }
451 
452 static inline struct device_node *of_get_child_by_name(
453 					const struct device_node *node,
454 					const char *name)
455 {
456 	return NULL;
457 }
458 
459 static inline int of_device_is_compatible(const struct device_node *device,
460 					  const char *name)
461 {
462 	return 0;
463 }
464 
465 static inline bool of_device_is_available(const struct device_node *device)
466 {
467 	return false;
468 }
469 
470 static inline struct property *of_find_property(const struct device_node *np,
471 						const char *name,
472 						int *lenp)
473 {
474 	return NULL;
475 }
476 
477 static inline struct device_node *of_find_compatible_node(
478 						struct device_node *from,
479 						const char *type,
480 						const char *compat)
481 {
482 	return NULL;
483 }
484 
485 static inline int of_property_count_elems_of_size(const struct device_node *np,
486 			const char *propname, int elem_size)
487 {
488 	return -ENOSYS;
489 }
490 
491 static inline int of_property_read_u32_index(const struct device_node *np,
492 			const char *propname, u32 index, u32 *out_value)
493 {
494 	return -ENOSYS;
495 }
496 
497 static inline int of_property_read_u8_array(const struct device_node *np,
498 			const char *propname, u8 *out_values, size_t sz)
499 {
500 	return -ENOSYS;
501 }
502 
503 static inline int of_property_read_u16_array(const struct device_node *np,
504 			const char *propname, u16 *out_values, size_t sz)
505 {
506 	return -ENOSYS;
507 }
508 
509 static inline int of_property_read_u32_array(const struct device_node *np,
510 					     const char *propname,
511 					     u32 *out_values, size_t sz)
512 {
513 	return -ENOSYS;
514 }
515 
516 static inline int of_property_read_u64_array(const struct device_node *np,
517 					     const char *propname,
518 					     u64 *out_values, size_t sz)
519 {
520 	return -ENOSYS;
521 }
522 
523 static inline int of_property_read_string(struct device_node *np,
524 					  const char *propname,
525 					  const char **out_string)
526 {
527 	return -ENOSYS;
528 }
529 
530 static inline int of_property_read_string_helper(struct device_node *np,
531 						 const char *propname,
532 						 const char **out_strs, size_t sz, int index)
533 {
534 	return -ENOSYS;
535 }
536 
537 static inline const void *of_get_property(const struct device_node *node,
538 				const char *name,
539 				int *lenp)
540 {
541 	return NULL;
542 }
543 
544 static inline struct device_node *of_get_cpu_node(int cpu,
545 					unsigned int *thread)
546 {
547 	return NULL;
548 }
549 
550 static inline int of_property_read_u64(const struct device_node *np,
551 				       const char *propname, u64 *out_value)
552 {
553 	return -ENOSYS;
554 }
555 
556 static inline int of_property_match_string(struct device_node *np,
557 					   const char *propname,
558 					   const char *string)
559 {
560 	return -ENOSYS;
561 }
562 
563 static inline struct device_node *of_parse_phandle(const struct device_node *np,
564 						   const char *phandle_name,
565 						   int index)
566 {
567 	return NULL;
568 }
569 
570 static inline int of_parse_phandle_with_args(struct device_node *np,
571 					     const char *list_name,
572 					     const char *cells_name,
573 					     int index,
574 					     struct of_phandle_args *out_args)
575 {
576 	return -ENOSYS;
577 }
578 
579 static inline int of_parse_phandle_with_fixed_args(const struct device_node *np,
580 	const char *list_name, int cells_count, int index,
581 	struct of_phandle_args *out_args)
582 {
583 	return -ENOSYS;
584 }
585 
586 static inline int of_count_phandle_with_args(struct device_node *np,
587 					     const char *list_name,
588 					     const char *cells_name)
589 {
590 	return -ENOSYS;
591 }
592 
593 static inline int of_alias_get_id(struct device_node *np, const char *stem)
594 {
595 	return -ENOSYS;
596 }
597 
598 static inline int of_alias_get_highest_id(const char *stem)
599 {
600 	return -ENOSYS;
601 }
602 
603 static inline int of_machine_is_compatible(const char *compat)
604 {
605 	return 0;
606 }
607 
608 static inline bool of_console_check(const struct device_node *dn, const char *name, int index)
609 {
610 	return false;
611 }
612 
613 static inline const __be32 *of_prop_next_u32(struct property *prop,
614 		const __be32 *cur, u32 *pu)
615 {
616 	return NULL;
617 }
618 
619 static inline const char *of_prop_next_string(struct property *prop,
620 		const char *cur)
621 {
622 	return NULL;
623 }
624 
625 #define of_match_ptr(_ptr)	NULL
626 #define of_match_node(_matches, _node)	NULL
627 #endif /* CONFIG_OF */
628 
629 #if defined(CONFIG_OF) && defined(CONFIG_NUMA)
630 extern int of_node_to_nid(struct device_node *np);
631 #else
632 static inline int of_node_to_nid(struct device_node *device) { return 0; }
633 #endif
634 
635 static inline struct device_node *of_find_matching_node(
636 	struct device_node *from,
637 	const struct of_device_id *matches)
638 {
639 	return of_find_matching_node_and_match(from, matches, NULL);
640 }
641 
642 /**
643  * of_property_count_u8_elems - Count the number of u8 elements in a property
644  *
645  * @np:		device node from which the property value is to be read.
646  * @propname:	name of the property to be searched.
647  *
648  * Search for a property in a device node and count the number of u8 elements
649  * in it. Returns number of elements on sucess, -EINVAL if the property does
650  * not exist or its length does not match a multiple of u8 and -ENODATA if the
651  * property does not have a value.
652  */
653 static inline int of_property_count_u8_elems(const struct device_node *np,
654 				const char *propname)
655 {
656 	return of_property_count_elems_of_size(np, propname, sizeof(u8));
657 }
658 
659 /**
660  * of_property_count_u16_elems - Count the number of u16 elements in a property
661  *
662  * @np:		device node from which the property value is to be read.
663  * @propname:	name of the property to be searched.
664  *
665  * Search for a property in a device node and count the number of u16 elements
666  * in it. Returns number of elements on sucess, -EINVAL if the property does
667  * not exist or its length does not match a multiple of u16 and -ENODATA if the
668  * property does not have a value.
669  */
670 static inline int of_property_count_u16_elems(const struct device_node *np,
671 				const char *propname)
672 {
673 	return of_property_count_elems_of_size(np, propname, sizeof(u16));
674 }
675 
676 /**
677  * of_property_count_u32_elems - Count the number of u32 elements in a property
678  *
679  * @np:		device node from which the property value is to be read.
680  * @propname:	name of the property to be searched.
681  *
682  * Search for a property in a device node and count the number of u32 elements
683  * in it. Returns number of elements on sucess, -EINVAL if the property does
684  * not exist or its length does not match a multiple of u32 and -ENODATA if the
685  * property does not have a value.
686  */
687 static inline int of_property_count_u32_elems(const struct device_node *np,
688 				const char *propname)
689 {
690 	return of_property_count_elems_of_size(np, propname, sizeof(u32));
691 }
692 
693 /**
694  * of_property_count_u64_elems - Count the number of u64 elements in a property
695  *
696  * @np:		device node from which the property value is to be read.
697  * @propname:	name of the property to be searched.
698  *
699  * Search for a property in a device node and count the number of u64 elements
700  * in it. Returns number of elements on sucess, -EINVAL if the property does
701  * not exist or its length does not match a multiple of u64 and -ENODATA if the
702  * property does not have a value.
703  */
704 static inline int of_property_count_u64_elems(const struct device_node *np,
705 				const char *propname)
706 {
707 	return of_property_count_elems_of_size(np, propname, sizeof(u64));
708 }
709 
710 /**
711  * of_property_read_string_array() - Read an array of strings from a multiple
712  * strings property.
713  * @np:		device node from which the property value is to be read.
714  * @propname:	name of the property to be searched.
715  * @out_strs:	output array of string pointers.
716  * @sz:		number of array elements to read.
717  *
718  * Search for a property in a device tree node and retrieve a list of
719  * terminated string values (pointer to data, not a copy) in that property.
720  *
721  * If @out_strs is NULL, the number of strings in the property is returned.
722  */
723 static inline int of_property_read_string_array(struct device_node *np,
724 						const char *propname, const char **out_strs,
725 						size_t sz)
726 {
727 	return of_property_read_string_helper(np, propname, out_strs, sz, 0);
728 }
729 
730 /**
731  * of_property_count_strings() - Find and return the number of strings from a
732  * multiple strings property.
733  * @np:		device node from which the property value is to be read.
734  * @propname:	name of the property to be searched.
735  *
736  * Search for a property in a device tree node and retrieve the number of null
737  * terminated string contain in it. Returns the number of strings on
738  * success, -EINVAL if the property does not exist, -ENODATA if property
739  * does not have a value, and -EILSEQ if the string is not null-terminated
740  * within the length of the property data.
741  */
742 static inline int of_property_count_strings(struct device_node *np,
743 					    const char *propname)
744 {
745 	return of_property_read_string_helper(np, propname, NULL, 0, 0);
746 }
747 
748 /**
749  * of_property_read_string_index() - Find and read a string from a multiple
750  * strings property.
751  * @np:		device node from which the property value is to be read.
752  * @propname:	name of the property to be searched.
753  * @index:	index of the string in the list of strings
754  * @out_string:	pointer to null terminated return string, modified only if
755  *		return value is 0.
756  *
757  * Search for a property in a device tree node and retrieve a null
758  * terminated string value (pointer to data, not a copy) in the list of strings
759  * contained in that property.
760  * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
761  * property does not have a value, and -EILSEQ if the string is not
762  * null-terminated within the length of the property data.
763  *
764  * The out_string pointer is modified only if a valid string can be decoded.
765  */
766 static inline int of_property_read_string_index(struct device_node *np,
767 						const char *propname,
768 						int index, const char **output)
769 {
770 	int rc = of_property_read_string_helper(np, propname, output, 1, index);
771 	return rc < 0 ? rc : 0;
772 }
773 
774 /**
775  * of_property_read_bool - Findfrom a property
776  * @np:		device node from which the property value is to be read.
777  * @propname:	name of the property to be searched.
778  *
779  * Search for a property in a device node.
780  * Returns true if the property exist false otherwise.
781  */
782 static inline bool of_property_read_bool(const struct device_node *np,
783 					 const char *propname)
784 {
785 	struct property *prop = of_find_property(np, propname, NULL);
786 
787 	return prop ? true : false;
788 }
789 
790 static inline int of_property_read_u8(const struct device_node *np,
791 				       const char *propname,
792 				       u8 *out_value)
793 {
794 	return of_property_read_u8_array(np, propname, out_value, 1);
795 }
796 
797 static inline int of_property_read_u16(const struct device_node *np,
798 				       const char *propname,
799 				       u16 *out_value)
800 {
801 	return of_property_read_u16_array(np, propname, out_value, 1);
802 }
803 
804 static inline int of_property_read_u32(const struct device_node *np,
805 				       const char *propname,
806 				       u32 *out_value)
807 {
808 	return of_property_read_u32_array(np, propname, out_value, 1);
809 }
810 
811 static inline int of_property_read_s32(const struct device_node *np,
812 				       const char *propname,
813 				       s32 *out_value)
814 {
815 	return of_property_read_u32(np, propname, (u32*) out_value);
816 }
817 
818 #define of_property_for_each_u32(np, propname, prop, p, u)	\
819 	for (prop = of_find_property(np, propname, NULL),	\
820 		p = of_prop_next_u32(prop, NULL, &u);		\
821 		p;						\
822 		p = of_prop_next_u32(prop, p, &u))
823 
824 #define of_property_for_each_string(np, propname, prop, s)	\
825 	for (prop = of_find_property(np, propname, NULL),	\
826 		s = of_prop_next_string(prop, NULL);		\
827 		s;						\
828 		s = of_prop_next_string(prop, s))
829 
830 #define for_each_node_by_name(dn, name) \
831 	for (dn = of_find_node_by_name(NULL, name); dn; \
832 	     dn = of_find_node_by_name(dn, name))
833 #define for_each_node_by_type(dn, type) \
834 	for (dn = of_find_node_by_type(NULL, type); dn; \
835 	     dn = of_find_node_by_type(dn, type))
836 #define for_each_compatible_node(dn, type, compatible) \
837 	for (dn = of_find_compatible_node(NULL, type, compatible); dn; \
838 	     dn = of_find_compatible_node(dn, type, compatible))
839 #define for_each_matching_node(dn, matches) \
840 	for (dn = of_find_matching_node(NULL, matches); dn; \
841 	     dn = of_find_matching_node(dn, matches))
842 #define for_each_matching_node_and_match(dn, matches, match) \
843 	for (dn = of_find_matching_node_and_match(NULL, matches, match); \
844 	     dn; dn = of_find_matching_node_and_match(dn, matches, match))
845 
846 #define for_each_child_of_node(parent, child) \
847 	for (child = of_get_next_child(parent, NULL); child != NULL; \
848 	     child = of_get_next_child(parent, child))
849 #define for_each_available_child_of_node(parent, child) \
850 	for (child = of_get_next_available_child(parent, NULL); child != NULL; \
851 	     child = of_get_next_available_child(parent, child))
852 
853 #define for_each_node_with_property(dn, prop_name) \
854 	for (dn = of_find_node_with_property(NULL, prop_name); dn; \
855 	     dn = of_find_node_with_property(dn, prop_name))
856 
857 static inline int of_get_child_count(const struct device_node *np)
858 {
859 	struct device_node *child;
860 	int num = 0;
861 
862 	for_each_child_of_node(np, child)
863 		num++;
864 
865 	return num;
866 }
867 
868 static inline int of_get_available_child_count(const struct device_node *np)
869 {
870 	struct device_node *child;
871 	int num = 0;
872 
873 	for_each_available_child_of_node(np, child)
874 		num++;
875 
876 	return num;
877 }
878 
879 #ifdef CONFIG_OF
880 #define _OF_DECLARE(table, name, compat, fn, fn_type)			\
881 	static const struct of_device_id __of_table_##name		\
882 		__used __section(__##table##_of_table)			\
883 		 = { .compatible = compat,				\
884 		     .data = (fn == (fn_type)NULL) ? fn : fn  }
885 #else
886 #define _OF_DECLARE(table, name, compat, fn, fn_type)			\
887 	static const struct of_device_id __of_table_##name		\
888 		__attribute__((unused))					\
889 		 = { .compatible = compat,				\
890 		     .data = (fn == (fn_type)NULL) ? fn : fn }
891 #endif
892 
893 typedef int (*of_init_fn_2)(struct device_node *, struct device_node *);
894 typedef void (*of_init_fn_1)(struct device_node *);
895 
896 #define OF_DECLARE_1(table, name, compat, fn) \
897 		_OF_DECLARE(table, name, compat, fn, of_init_fn_1)
898 #define OF_DECLARE_2(table, name, compat, fn) \
899 		_OF_DECLARE(table, name, compat, fn, of_init_fn_2)
900 
901 /**
902  * struct of_changeset_entry	- Holds a changeset entry
903  *
904  * @node:	list_head for the log list
905  * @action:	notifier action
906  * @np:		pointer to the device node affected
907  * @prop:	pointer to the property affected
908  * @old_prop:	hold a pointer to the original property
909  *
910  * Every modification of the device tree during a changeset
911  * is held in a list of of_changeset_entry structures.
912  * That way we can recover from a partial application, or we can
913  * revert the changeset
914  */
915 struct of_changeset_entry {
916 	struct list_head node;
917 	unsigned long action;
918 	struct device_node *np;
919 	struct property *prop;
920 	struct property *old_prop;
921 };
922 
923 /**
924  * struct of_changeset - changeset tracker structure
925  *
926  * @entries:	list_head for the changeset entries
927  *
928  * changesets are a convenient way to apply bulk changes to the
929  * live tree. In case of an error, changes are rolled-back.
930  * changesets live on after initial application, and if not
931  * destroyed after use, they can be reverted in one single call.
932  */
933 struct of_changeset {
934 	struct list_head entries;
935 };
936 
937 enum of_reconfig_change {
938 	OF_RECONFIG_NO_CHANGE = 0,
939 	OF_RECONFIG_CHANGE_ADD,
940 	OF_RECONFIG_CHANGE_REMOVE,
941 };
942 
943 #ifdef CONFIG_OF_DYNAMIC
944 extern int of_reconfig_notifier_register(struct notifier_block *);
945 extern int of_reconfig_notifier_unregister(struct notifier_block *);
946 extern int of_reconfig_notify(unsigned long, struct of_reconfig_data *rd);
947 extern int of_reconfig_get_state_change(unsigned long action,
948 					struct of_reconfig_data *arg);
949 
950 extern void of_changeset_init(struct of_changeset *ocs);
951 extern void of_changeset_destroy(struct of_changeset *ocs);
952 extern int of_changeset_apply(struct of_changeset *ocs);
953 extern int of_changeset_revert(struct of_changeset *ocs);
954 extern int of_changeset_action(struct of_changeset *ocs,
955 		unsigned long action, struct device_node *np,
956 		struct property *prop);
957 
958 static inline int of_changeset_attach_node(struct of_changeset *ocs,
959 		struct device_node *np)
960 {
961 	return of_changeset_action(ocs, OF_RECONFIG_ATTACH_NODE, np, NULL);
962 }
963 
964 static inline int of_changeset_detach_node(struct of_changeset *ocs,
965 		struct device_node *np)
966 {
967 	return of_changeset_action(ocs, OF_RECONFIG_DETACH_NODE, np, NULL);
968 }
969 
970 static inline int of_changeset_add_property(struct of_changeset *ocs,
971 		struct device_node *np, struct property *prop)
972 {
973 	return of_changeset_action(ocs, OF_RECONFIG_ADD_PROPERTY, np, prop);
974 }
975 
976 static inline int of_changeset_remove_property(struct of_changeset *ocs,
977 		struct device_node *np, struct property *prop)
978 {
979 	return of_changeset_action(ocs, OF_RECONFIG_REMOVE_PROPERTY, np, prop);
980 }
981 
982 static inline int of_changeset_update_property(struct of_changeset *ocs,
983 		struct device_node *np, struct property *prop)
984 {
985 	return of_changeset_action(ocs, OF_RECONFIG_UPDATE_PROPERTY, np, prop);
986 }
987 #else /* CONFIG_OF_DYNAMIC */
988 static inline int of_reconfig_notifier_register(struct notifier_block *nb)
989 {
990 	return -EINVAL;
991 }
992 static inline int of_reconfig_notifier_unregister(struct notifier_block *nb)
993 {
994 	return -EINVAL;
995 }
996 static inline int of_reconfig_notify(unsigned long action,
997 				     struct of_reconfig_data *arg)
998 {
999 	return -EINVAL;
1000 }
1001 static inline int of_reconfig_get_state_change(unsigned long action,
1002 						struct of_reconfig_data *arg)
1003 {
1004 	return -EINVAL;
1005 }
1006 #endif /* CONFIG_OF_DYNAMIC */
1007 
1008 /* CONFIG_OF_RESOLVE api */
1009 extern int of_resolve_phandles(struct device_node *tree);
1010 
1011 /**
1012  * of_device_is_system_power_controller - Tells if system-power-controller is found for device_node
1013  * @np: Pointer to the given device_node
1014  *
1015  * return true if present false otherwise
1016  */
1017 static inline bool of_device_is_system_power_controller(const struct device_node *np)
1018 {
1019 	return of_property_read_bool(np, "system-power-controller");
1020 }
1021 
1022 /**
1023  * Overlay support
1024  */
1025 
1026 #ifdef CONFIG_OF_OVERLAY
1027 
1028 /* ID based overlays; the API for external users */
1029 int of_overlay_create(struct device_node *tree);
1030 int of_overlay_destroy(int id);
1031 int of_overlay_destroy_all(void);
1032 
1033 #else
1034 
1035 static inline int of_overlay_create(struct device_node *tree)
1036 {
1037 	return -ENOTSUPP;
1038 }
1039 
1040 static inline int of_overlay_destroy(int id)
1041 {
1042 	return -ENOTSUPP;
1043 }
1044 
1045 static inline int of_overlay_destroy_all(void)
1046 {
1047 	return -ENOTSUPP;
1048 }
1049 
1050 #endif
1051 
1052 #endif /* _LINUX_OF_H */
1053