2 * Procedures for creating, accessing and interpreting the device tree.
4 * Paul Mackerras August 1996.
5 * Copyright (C) 1996-2005 Paul Mackerras.
7 * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
8 * {engebret|bergner}@us.ibm.com
10 * Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net
12 * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
20 #include <linux/ctype.h>
21 #include <linux/cpu.h>
22 #include <linux/module.h>
24 #include <linux/spinlock.h>
25 #include <linux/slab.h>
26 #include <linux/proc_fs.h>
28 #include "of_private.h"
30 LIST_HEAD(aliases_lookup
);
32 struct device_node
*of_allnodes
;
33 EXPORT_SYMBOL(of_allnodes
);
34 struct device_node
*of_chosen
;
35 struct device_node
*of_aliases
;
36 static struct device_node
*of_stdout
;
38 DEFINE_MUTEX(of_aliases_mutex
);
40 /* use when traversing tree through the allnext, child, sibling,
41 * or parent members of struct device_node.
43 DEFINE_RAW_SPINLOCK(devtree_lock
);
45 int of_n_addr_cells(struct device_node
*np
)
52 ip
= of_get_property(np
, "#address-cells", NULL
);
54 return be32_to_cpup(ip
);
56 /* No #address-cells property for the root node */
57 return OF_ROOT_NODE_ADDR_CELLS_DEFAULT
;
59 EXPORT_SYMBOL(of_n_addr_cells
);
61 int of_n_size_cells(struct device_node
*np
)
68 ip
= of_get_property(np
, "#size-cells", NULL
);
70 return be32_to_cpup(ip
);
72 /* No #size-cells property for the root node */
73 return OF_ROOT_NODE_SIZE_CELLS_DEFAULT
;
75 EXPORT_SYMBOL(of_n_size_cells
);
78 int __weak
of_node_to_nid(struct device_node
*np
)
80 return numa_node_id();
84 #if defined(CONFIG_OF_DYNAMIC)
86 * of_node_get - Increment refcount of a node
87 * @node: Node to inc refcount, NULL is supported to
88 * simplify writing of callers
92 struct device_node
*of_node_get(struct device_node
*node
)
95 kref_get(&node
->kref
);
98 EXPORT_SYMBOL(of_node_get
);
100 static inline struct device_node
*kref_to_device_node(struct kref
*kref
)
102 return container_of(kref
, struct device_node
, kref
);
106 * of_node_release - release a dynamically allocated node
107 * @kref: kref element of the node to be released
109 * In of_node_put() this function is passed to kref_put()
112 static void of_node_release(struct kref
*kref
)
114 struct device_node
*node
= kref_to_device_node(kref
);
115 struct property
*prop
= node
->properties
;
117 /* We should never be releasing nodes that haven't been detached. */
118 if (!of_node_check_flag(node
, OF_DETACHED
)) {
119 pr_err("ERROR: Bad of_node_put() on %s\n", node
->full_name
);
121 kref_init(&node
->kref
);
125 if (!of_node_check_flag(node
, OF_DYNAMIC
))
129 struct property
*next
= prop
->next
;
136 prop
= node
->deadprops
;
137 node
->deadprops
= NULL
;
140 kfree(node
->full_name
);
146 * of_node_put - Decrement refcount of a node
147 * @node: Node to dec refcount, NULL is supported to
148 * simplify writing of callers
151 void of_node_put(struct device_node
*node
)
154 kref_put(&node
->kref
, of_node_release
);
156 EXPORT_SYMBOL(of_node_put
);
157 #endif /* CONFIG_OF_DYNAMIC */
159 static struct property
*__of_find_property(const struct device_node
*np
,
160 const char *name
, int *lenp
)
167 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
168 if (of_prop_cmp(pp
->name
, name
) == 0) {
178 struct property
*of_find_property(const struct device_node
*np
,
185 raw_spin_lock_irqsave(&devtree_lock
, flags
);
186 pp
= __of_find_property(np
, name
, lenp
);
187 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
191 EXPORT_SYMBOL(of_find_property
);
194 * of_find_all_nodes - Get next node in global list
195 * @prev: Previous node or NULL to start iteration
196 * of_node_put() will be called on it
198 * Returns a node pointer with refcount incremented, use
199 * of_node_put() on it when done.
201 struct device_node
*of_find_all_nodes(struct device_node
*prev
)
203 struct device_node
*np
;
206 raw_spin_lock_irqsave(&devtree_lock
, flags
);
207 np
= prev
? prev
->allnext
: of_allnodes
;
208 for (; np
!= NULL
; np
= np
->allnext
)
212 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
215 EXPORT_SYMBOL(of_find_all_nodes
);
218 * Find a property with a given name for a given node
219 * and return the value.
221 static const void *__of_get_property(const struct device_node
*np
,
222 const char *name
, int *lenp
)
224 struct property
*pp
= __of_find_property(np
, name
, lenp
);
226 return pp
? pp
->value
: NULL
;
230 * Find a property with a given name for a given node
231 * and return the value.
233 const void *of_get_property(const struct device_node
*np
, const char *name
,
236 struct property
*pp
= of_find_property(np
, name
, lenp
);
238 return pp
? pp
->value
: NULL
;
240 EXPORT_SYMBOL(of_get_property
);
243 * arch_match_cpu_phys_id - Match the given logical CPU and physical id
245 * @cpu: logical cpu index of a core/thread
246 * @phys_id: physical identifier of a core/thread
248 * CPU logical to physical index mapping is architecture specific.
249 * However this __weak function provides a default match of physical
250 * id to logical cpu index. phys_id provided here is usually values read
251 * from the device tree which must match the hardware internal registers.
253 * Returns true if the physical identifier and the logical cpu index
254 * correspond to the same core/thread, false otherwise.
256 bool __weak
arch_match_cpu_phys_id(int cpu
, u64 phys_id
)
258 return (u32
)phys_id
== cpu
;
262 * Checks if the given "prop_name" property holds the physical id of the
263 * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
264 * NULL, local thread number within the core is returned in it.
266 static bool __of_find_n_match_cpu_property(struct device_node
*cpun
,
267 const char *prop_name
, int cpu
, unsigned int *thread
)
270 int ac
, prop_len
, tid
;
273 ac
= of_n_addr_cells(cpun
);
274 cell
= of_get_property(cpun
, prop_name
, &prop_len
);
277 prop_len
/= sizeof(*cell
) * ac
;
278 for (tid
= 0; tid
< prop_len
; tid
++) {
279 hwid
= of_read_number(cell
, ac
);
280 if (arch_match_cpu_phys_id(cpu
, hwid
)) {
291 * arch_find_n_match_cpu_physical_id - See if the given device node is
292 * for the cpu corresponding to logical cpu 'cpu'. Return true if so,
293 * else false. If 'thread' is non-NULL, the local thread number within the
294 * core is returned in it.
296 bool __weak
arch_find_n_match_cpu_physical_id(struct device_node
*cpun
,
297 int cpu
, unsigned int *thread
)
299 /* Check for non-standard "ibm,ppc-interrupt-server#s" property
300 * for thread ids on PowerPC. If it doesn't exist fallback to
301 * standard "reg" property.
303 if (IS_ENABLED(CONFIG_PPC
) &&
304 __of_find_n_match_cpu_property(cpun
,
305 "ibm,ppc-interrupt-server#s",
309 if (__of_find_n_match_cpu_property(cpun
, "reg", cpu
, thread
))
316 * of_get_cpu_node - Get device node associated with the given logical CPU
318 * @cpu: CPU number(logical index) for which device node is required
319 * @thread: if not NULL, local thread number within the physical core is
322 * The main purpose of this function is to retrieve the device node for the
323 * given logical CPU index. It should be used to initialize the of_node in
324 * cpu device. Once of_node in cpu device is populated, all the further
325 * references can use that instead.
327 * CPU logical to physical index mapping is architecture specific and is built
328 * before booting secondary cores. This function uses arch_match_cpu_phys_id
329 * which can be overridden by architecture specific implementation.
331 * Returns a node pointer for the logical cpu if found, else NULL.
333 struct device_node
*of_get_cpu_node(int cpu
, unsigned int *thread
)
335 struct device_node
*cpun
;
337 for_each_node_by_type(cpun
, "cpu") {
338 if (arch_find_n_match_cpu_physical_id(cpun
, cpu
, thread
))
343 EXPORT_SYMBOL(of_get_cpu_node
);
346 * __of_device_is_compatible() - Check if the node matches given constraints
347 * @device: pointer to node
348 * @compat: required compatible string, NULL or "" for any match
349 * @type: required device_type value, NULL or "" for any match
350 * @name: required node name, NULL or "" for any match
352 * Checks if the given @compat, @type and @name strings match the
353 * properties of the given @device. A constraints can be skipped by
354 * passing NULL or an empty string as the constraint.
356 * Returns 0 for no match, and a positive integer on match. The return
357 * value is a relative score with larger values indicating better
358 * matches. The score is weighted for the most specific compatible value
359 * to get the highest score. Matching type is next, followed by matching
360 * name. Practically speaking, this results in the following priority
363 * 1. specific compatible && type && name
364 * 2. specific compatible && type
365 * 3. specific compatible && name
366 * 4. specific compatible
367 * 5. general compatible && type && name
368 * 6. general compatible && type
369 * 7. general compatible && name
370 * 8. general compatible
375 static int __of_device_is_compatible(const struct device_node
*device
,
376 const char *compat
, const char *type
, const char *name
)
378 struct property
*prop
;
380 int index
= 0, score
= 0;
382 /* Compatible match has highest priority */
383 if (compat
&& compat
[0]) {
384 prop
= __of_find_property(device
, "compatible", NULL
);
385 for (cp
= of_prop_next_string(prop
, NULL
); cp
;
386 cp
= of_prop_next_string(prop
, cp
), index
++) {
387 if (of_compat_cmp(cp
, compat
, strlen(compat
)) == 0) {
388 score
= INT_MAX
/2 - (index
<< 2);
396 /* Matching type is better than matching name */
397 if (type
&& type
[0]) {
398 if (!device
->type
|| of_node_cmp(type
, device
->type
))
403 /* Matching name is a bit better than not */
404 if (name
&& name
[0]) {
405 if (!device
->name
|| of_node_cmp(name
, device
->name
))
413 /** Checks if the given "compat" string matches one of the strings in
414 * the device's "compatible" property
416 int of_device_is_compatible(const struct device_node
*device
,
422 raw_spin_lock_irqsave(&devtree_lock
, flags
);
423 res
= __of_device_is_compatible(device
, compat
, NULL
, NULL
);
424 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
427 EXPORT_SYMBOL(of_device_is_compatible
);
430 * of_machine_is_compatible - Test root of device tree for a given compatible value
431 * @compat: compatible string to look for in root node's compatible property.
433 * Returns true if the root node has the given value in its
434 * compatible property.
436 int of_machine_is_compatible(const char *compat
)
438 struct device_node
*root
;
441 root
= of_find_node_by_path("/");
443 rc
= of_device_is_compatible(root
, compat
);
448 EXPORT_SYMBOL(of_machine_is_compatible
);
451 * __of_device_is_available - check if a device is available for use
453 * @device: Node to check for availability, with locks already held
455 * Returns 1 if the status property is absent or set to "okay" or "ok",
458 static int __of_device_is_available(const struct device_node
*device
)
466 status
= __of_get_property(device
, "status", &statlen
);
471 if (!strcmp(status
, "okay") || !strcmp(status
, "ok"))
479 * of_device_is_available - check if a device is available for use
481 * @device: Node to check for availability
483 * Returns 1 if the status property is absent or set to "okay" or "ok",
486 int of_device_is_available(const struct device_node
*device
)
491 raw_spin_lock_irqsave(&devtree_lock
, flags
);
492 res
= __of_device_is_available(device
);
493 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
497 EXPORT_SYMBOL(of_device_is_available
);
500 * of_get_parent - Get a node's parent if any
501 * @node: Node to get parent
503 * Returns a node pointer with refcount incremented, use
504 * of_node_put() on it when done.
506 struct device_node
*of_get_parent(const struct device_node
*node
)
508 struct device_node
*np
;
514 raw_spin_lock_irqsave(&devtree_lock
, flags
);
515 np
= of_node_get(node
->parent
);
516 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
519 EXPORT_SYMBOL(of_get_parent
);
522 * of_get_next_parent - Iterate to a node's parent
523 * @node: Node to get parent of
525 * This is like of_get_parent() except that it drops the
526 * refcount on the passed node, making it suitable for iterating
527 * through a node's parents.
529 * Returns a node pointer with refcount incremented, use
530 * of_node_put() on it when done.
532 struct device_node
*of_get_next_parent(struct device_node
*node
)
534 struct device_node
*parent
;
540 raw_spin_lock_irqsave(&devtree_lock
, flags
);
541 parent
= of_node_get(node
->parent
);
543 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
546 EXPORT_SYMBOL(of_get_next_parent
);
549 * of_get_next_child - Iterate a node childs
551 * @prev: previous child of the parent node, or NULL to get first
553 * Returns a node pointer with refcount incremented, use
554 * of_node_put() on it when done.
556 struct device_node
*of_get_next_child(const struct device_node
*node
,
557 struct device_node
*prev
)
559 struct device_node
*next
;
562 raw_spin_lock_irqsave(&devtree_lock
, flags
);
563 next
= prev
? prev
->sibling
: node
->child
;
564 for (; next
; next
= next
->sibling
)
565 if (of_node_get(next
))
568 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
571 EXPORT_SYMBOL(of_get_next_child
);
574 * of_get_next_available_child - Find the next available child node
576 * @prev: previous child of the parent node, or NULL to get first
578 * This function is like of_get_next_child(), except that it
579 * automatically skips any disabled nodes (i.e. status = "disabled").
581 struct device_node
*of_get_next_available_child(const struct device_node
*node
,
582 struct device_node
*prev
)
584 struct device_node
*next
;
587 raw_spin_lock_irqsave(&devtree_lock
, flags
);
588 next
= prev
? prev
->sibling
: node
->child
;
589 for (; next
; next
= next
->sibling
) {
590 if (!__of_device_is_available(next
))
592 if (of_node_get(next
))
596 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
599 EXPORT_SYMBOL(of_get_next_available_child
);
602 * of_get_child_by_name - Find the child node by name for a given parent
604 * @name: child name to look for.
606 * This function looks for child node for given matching name
608 * Returns a node pointer if found, with refcount incremented, use
609 * of_node_put() on it when done.
610 * Returns NULL if node is not found.
612 struct device_node
*of_get_child_by_name(const struct device_node
*node
,
615 struct device_node
*child
;
617 for_each_child_of_node(node
, child
)
618 if (child
->name
&& (of_node_cmp(child
->name
, name
) == 0))
622 EXPORT_SYMBOL(of_get_child_by_name
);
625 * of_find_node_by_path - Find a node matching a full OF path
626 * @path: The full path to match
628 * Returns a node pointer with refcount incremented, use
629 * of_node_put() on it when done.
631 struct device_node
*of_find_node_by_path(const char *path
)
633 struct device_node
*np
= of_allnodes
;
636 raw_spin_lock_irqsave(&devtree_lock
, flags
);
637 for (; np
; np
= np
->allnext
) {
638 if (np
->full_name
&& (of_node_cmp(np
->full_name
, path
) == 0)
642 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
645 EXPORT_SYMBOL(of_find_node_by_path
);
648 * of_find_node_by_name - Find a node by its "name" property
649 * @from: The node to start searching from or NULL, the node
650 * you pass will not be searched, only the next one
651 * will; typically, you pass what the previous call
652 * returned. of_node_put() will be called on it
653 * @name: The name string to match against
655 * Returns a node pointer with refcount incremented, use
656 * of_node_put() on it when done.
658 struct device_node
*of_find_node_by_name(struct device_node
*from
,
661 struct device_node
*np
;
664 raw_spin_lock_irqsave(&devtree_lock
, flags
);
665 np
= from
? from
->allnext
: of_allnodes
;
666 for (; np
; np
= np
->allnext
)
667 if (np
->name
&& (of_node_cmp(np
->name
, name
) == 0)
671 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
674 EXPORT_SYMBOL(of_find_node_by_name
);
677 * of_find_node_by_type - Find a node by its "device_type" property
678 * @from: The node to start searching from, or NULL to start searching
679 * the entire device tree. The node you pass will not be
680 * searched, only the next one will; typically, you pass
681 * what the previous call returned. of_node_put() will be
682 * called on from for you.
683 * @type: The type string to match against
685 * Returns a node pointer with refcount incremented, use
686 * of_node_put() on it when done.
688 struct device_node
*of_find_node_by_type(struct device_node
*from
,
691 struct device_node
*np
;
694 raw_spin_lock_irqsave(&devtree_lock
, flags
);
695 np
= from
? from
->allnext
: of_allnodes
;
696 for (; np
; np
= np
->allnext
)
697 if (np
->type
&& (of_node_cmp(np
->type
, type
) == 0)
701 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
704 EXPORT_SYMBOL(of_find_node_by_type
);
707 * of_find_compatible_node - Find a node based on type and one of the
708 * tokens in its "compatible" property
709 * @from: The node to start searching from or NULL, the node
710 * you pass will not be searched, only the next one
711 * will; typically, you pass what the previous call
712 * returned. of_node_put() will be called on it
713 * @type: The type string to match "device_type" or NULL to ignore
714 * @compatible: The string to match to one of the tokens in the device
717 * Returns a node pointer with refcount incremented, use
718 * of_node_put() on it when done.
720 struct device_node
*of_find_compatible_node(struct device_node
*from
,
721 const char *type
, const char *compatible
)
723 struct device_node
*np
;
726 raw_spin_lock_irqsave(&devtree_lock
, flags
);
727 np
= from
? from
->allnext
: of_allnodes
;
728 for (; np
; np
= np
->allnext
) {
729 if (__of_device_is_compatible(np
, compatible
, type
, NULL
) &&
734 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
737 EXPORT_SYMBOL(of_find_compatible_node
);
740 * of_find_node_with_property - Find a node which has a property with
742 * @from: The node to start searching from or NULL, the node
743 * you pass will not be searched, only the next one
744 * will; typically, you pass what the previous call
745 * returned. of_node_put() will be called on it
746 * @prop_name: The name of the property to look for.
748 * Returns a node pointer with refcount incremented, use
749 * of_node_put() on it when done.
751 struct device_node
*of_find_node_with_property(struct device_node
*from
,
752 const char *prop_name
)
754 struct device_node
*np
;
758 raw_spin_lock_irqsave(&devtree_lock
, flags
);
759 np
= from
? from
->allnext
: of_allnodes
;
760 for (; np
; np
= np
->allnext
) {
761 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
762 if (of_prop_cmp(pp
->name
, prop_name
) == 0) {
770 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
773 EXPORT_SYMBOL(of_find_node_with_property
);
776 const struct of_device_id
*__of_match_node(const struct of_device_id
*matches
,
777 const struct device_node
*node
)
779 const struct of_device_id
*best_match
= NULL
;
780 int score
, best_score
= 0;
785 for (; matches
->name
[0] || matches
->type
[0] || matches
->compatible
[0]; matches
++) {
786 score
= __of_device_is_compatible(node
, matches
->compatible
,
787 matches
->type
, matches
->name
);
788 if (score
> best_score
) {
789 best_match
= matches
;
798 * of_match_node - Tell if an device_node has a matching of_match structure
799 * @matches: array of of device match structures to search in
800 * @node: the of device structure to match against
802 * Low level utility function used by device matching.
804 const struct of_device_id
*of_match_node(const struct of_device_id
*matches
,
805 const struct device_node
*node
)
807 const struct of_device_id
*match
;
810 raw_spin_lock_irqsave(&devtree_lock
, flags
);
811 match
= __of_match_node(matches
, node
);
812 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
815 EXPORT_SYMBOL(of_match_node
);
818 * of_find_matching_node_and_match - Find a node based on an of_device_id
820 * @from: The node to start searching from or NULL, the node
821 * you pass will not be searched, only the next one
822 * will; typically, you pass what the previous call
823 * returned. of_node_put() will be called on it
824 * @matches: array of of device match structures to search in
825 * @match Updated to point at the matches entry which matched
827 * Returns a node pointer with refcount incremented, use
828 * of_node_put() on it when done.
830 struct device_node
*of_find_matching_node_and_match(struct device_node
*from
,
831 const struct of_device_id
*matches
,
832 const struct of_device_id
**match
)
834 struct device_node
*np
;
835 const struct of_device_id
*m
;
841 raw_spin_lock_irqsave(&devtree_lock
, flags
);
842 np
= from
? from
->allnext
: of_allnodes
;
843 for (; np
; np
= np
->allnext
) {
844 m
= __of_match_node(matches
, np
);
845 if (m
&& of_node_get(np
)) {
852 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
855 EXPORT_SYMBOL(of_find_matching_node_and_match
);
858 * of_modalias_node - Lookup appropriate modalias for a device node
859 * @node: pointer to a device tree node
860 * @modalias: Pointer to buffer that modalias value will be copied into
861 * @len: Length of modalias value
863 * Based on the value of the compatible property, this routine will attempt
864 * to choose an appropriate modalias value for a particular device tree node.
865 * It does this by stripping the manufacturer prefix (as delimited by a ',')
866 * from the first entry in the compatible list property.
868 * This routine returns 0 on success, <0 on failure.
870 int of_modalias_node(struct device_node
*node
, char *modalias
, int len
)
872 const char *compatible
, *p
;
875 compatible
= of_get_property(node
, "compatible", &cplen
);
876 if (!compatible
|| strlen(compatible
) > cplen
)
878 p
= strchr(compatible
, ',');
879 strlcpy(modalias
, p
? p
+ 1 : compatible
, len
);
882 EXPORT_SYMBOL_GPL(of_modalias_node
);
885 * of_find_node_by_phandle - Find a node given a phandle
886 * @handle: phandle of the node to find
888 * Returns a node pointer with refcount incremented, use
889 * of_node_put() on it when done.
891 struct device_node
*of_find_node_by_phandle(phandle handle
)
893 struct device_node
*np
;
896 raw_spin_lock_irqsave(&devtree_lock
, flags
);
897 for (np
= of_allnodes
; np
; np
= np
->allnext
)
898 if (np
->phandle
== handle
)
901 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
904 EXPORT_SYMBOL(of_find_node_by_phandle
);
907 * of_find_property_value_of_size
909 * @np: device node from which the property value is to be read.
910 * @propname: name of the property to be searched.
911 * @len: requested length of property value
913 * Search for a property in a device node and valid the requested size.
914 * Returns the property value on success, -EINVAL if the property does not
915 * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
916 * property data isn't large enough.
919 static void *of_find_property_value_of_size(const struct device_node
*np
,
920 const char *propname
, u32 len
)
922 struct property
*prop
= of_find_property(np
, propname
, NULL
);
925 return ERR_PTR(-EINVAL
);
927 return ERR_PTR(-ENODATA
);
928 if (len
> prop
->length
)
929 return ERR_PTR(-EOVERFLOW
);
935 * of_property_read_u32_index - Find and read a u32 from a multi-value property.
937 * @np: device node from which the property value is to be read.
938 * @propname: name of the property to be searched.
939 * @index: index of the u32 in the list of values
940 * @out_value: pointer to return value, modified only if no error.
942 * Search for a property in a device node and read nth 32-bit value from
943 * it. Returns 0 on success, -EINVAL if the property does not exist,
944 * -ENODATA if property does not have a value, and -EOVERFLOW if the
945 * property data isn't large enough.
947 * The out_value is modified only if a valid u32 value can be decoded.
949 int of_property_read_u32_index(const struct device_node
*np
,
950 const char *propname
,
951 u32 index
, u32
*out_value
)
953 const u32
*val
= of_find_property_value_of_size(np
, propname
,
954 ((index
+ 1) * sizeof(*out_value
)));
959 *out_value
= be32_to_cpup(((__be32
*)val
) + index
);
962 EXPORT_SYMBOL_GPL(of_property_read_u32_index
);
965 * of_property_read_u8_array - Find and read an array of u8 from a property.
967 * @np: device node from which the property value is to be read.
968 * @propname: name of the property to be searched.
969 * @out_values: pointer to return value, modified only if return value is 0.
970 * @sz: number of array elements to read
972 * Search for a property in a device node and read 8-bit value(s) from
973 * it. Returns 0 on success, -EINVAL if the property does not exist,
974 * -ENODATA if property does not have a value, and -EOVERFLOW if the
975 * property data isn't large enough.
977 * dts entry of array should be like:
978 * property = /bits/ 8 <0x50 0x60 0x70>;
980 * The out_values is modified only if a valid u8 value can be decoded.
982 int of_property_read_u8_array(const struct device_node
*np
,
983 const char *propname
, u8
*out_values
, size_t sz
)
985 const u8
*val
= of_find_property_value_of_size(np
, propname
,
986 (sz
* sizeof(*out_values
)));
992 *out_values
++ = *val
++;
995 EXPORT_SYMBOL_GPL(of_property_read_u8_array
);
998 * of_property_read_u16_array - Find and read an array of u16 from a property.
1000 * @np: device node from which the property value is to be read.
1001 * @propname: name of the property to be searched.
1002 * @out_values: pointer to return value, modified only if return value is 0.
1003 * @sz: number of array elements to read
1005 * Search for a property in a device node and read 16-bit value(s) from
1006 * it. Returns 0 on success, -EINVAL if the property does not exist,
1007 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1008 * property data isn't large enough.
1010 * dts entry of array should be like:
1011 * property = /bits/ 16 <0x5000 0x6000 0x7000>;
1013 * The out_values is modified only if a valid u16 value can be decoded.
1015 int of_property_read_u16_array(const struct device_node
*np
,
1016 const char *propname
, u16
*out_values
, size_t sz
)
1018 const __be16
*val
= of_find_property_value_of_size(np
, propname
,
1019 (sz
* sizeof(*out_values
)));
1022 return PTR_ERR(val
);
1025 *out_values
++ = be16_to_cpup(val
++);
1028 EXPORT_SYMBOL_GPL(of_property_read_u16_array
);
1031 * of_property_read_u32_array - Find and read an array of 32 bit integers
1034 * @np: device node from which the property value is to be read.
1035 * @propname: name of the property to be searched.
1036 * @out_values: pointer to return value, modified only if return value is 0.
1037 * @sz: number of array elements to read
1039 * Search for a property in a device node and read 32-bit value(s) from
1040 * it. Returns 0 on success, -EINVAL if the property does not exist,
1041 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1042 * property data isn't large enough.
1044 * The out_values is modified only if a valid u32 value can be decoded.
1046 int of_property_read_u32_array(const struct device_node
*np
,
1047 const char *propname
, u32
*out_values
,
1050 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1051 (sz
* sizeof(*out_values
)));
1054 return PTR_ERR(val
);
1057 *out_values
++ = be32_to_cpup(val
++);
1060 EXPORT_SYMBOL_GPL(of_property_read_u32_array
);
1063 * of_property_read_u64 - Find and read a 64 bit integer from a property
1064 * @np: device node from which the property value is to be read.
1065 * @propname: name of the property to be searched.
1066 * @out_value: pointer to return value, modified only if return value is 0.
1068 * Search for a property in a device node and read a 64-bit value from
1069 * it. Returns 0 on success, -EINVAL if the property does not exist,
1070 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1071 * property data isn't large enough.
1073 * The out_value is modified only if a valid u64 value can be decoded.
1075 int of_property_read_u64(const struct device_node
*np
, const char *propname
,
1078 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1079 sizeof(*out_value
));
1082 return PTR_ERR(val
);
1084 *out_value
= of_read_number(val
, 2);
1087 EXPORT_SYMBOL_GPL(of_property_read_u64
);
1090 * of_property_read_string - Find and read a string from a property
1091 * @np: device node from which the property value is to be read.
1092 * @propname: name of the property to be searched.
1093 * @out_string: pointer to null terminated return string, modified only if
1094 * return value is 0.
1096 * Search for a property in a device tree node and retrieve a null
1097 * terminated string value (pointer to data, not a copy). Returns 0 on
1098 * success, -EINVAL if the property does not exist, -ENODATA if property
1099 * does not have a value, and -EILSEQ if the string is not null-terminated
1100 * within the length of the property data.
1102 * The out_string pointer is modified only if a valid string can be decoded.
1104 int of_property_read_string(struct device_node
*np
, const char *propname
,
1105 const char **out_string
)
1107 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1112 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1114 *out_string
= prop
->value
;
1117 EXPORT_SYMBOL_GPL(of_property_read_string
);
1120 * of_property_read_string_index - Find and read a string from a multiple
1122 * @np: device node from which the property value is to be read.
1123 * @propname: name of the property to be searched.
1124 * @index: index of the string in the list of strings
1125 * @out_string: pointer to null terminated return string, modified only if
1126 * return value is 0.
1128 * Search for a property in a device tree node and retrieve a null
1129 * terminated string value (pointer to data, not a copy) in the list of strings
1130 * contained in that property.
1131 * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
1132 * property does not have a value, and -EILSEQ if the string is not
1133 * null-terminated within the length of the property data.
1135 * The out_string pointer is modified only if a valid string can be decoded.
1137 int of_property_read_string_index(struct device_node
*np
, const char *propname
,
1138 int index
, const char **output
)
1140 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1142 size_t l
= 0, total
= 0;
1149 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1154 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
) {
1163 EXPORT_SYMBOL_GPL(of_property_read_string_index
);
1166 * of_property_match_string() - Find string in a list and return index
1167 * @np: pointer to node containing string list property
1168 * @propname: string list property name
1169 * @string: pointer to string to search for in string list
1171 * This function searches a string list property and returns the index
1172 * of a specific string value.
1174 int of_property_match_string(struct device_node
*np
, const char *propname
,
1177 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1180 const char *p
, *end
;
1188 end
= p
+ prop
->length
;
1190 for (i
= 0; p
< end
; i
++, p
+= l
) {
1194 pr_debug("comparing %s with %s\n", string
, p
);
1195 if (strcmp(string
, p
) == 0)
1196 return i
; /* Found it; return index */
1200 EXPORT_SYMBOL_GPL(of_property_match_string
);
1203 * of_property_count_strings - Find and return the number of strings from a
1204 * multiple strings property.
1205 * @np: device node from which the property value is to be read.
1206 * @propname: name of the property to be searched.
1208 * Search for a property in a device tree node and retrieve the number of null
1209 * terminated string contain in it. Returns the number of strings on
1210 * success, -EINVAL if the property does not exist, -ENODATA if property
1211 * does not have a value, and -EILSEQ if the string is not null-terminated
1212 * within the length of the property data.
1214 int of_property_count_strings(struct device_node
*np
, const char *propname
)
1216 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1218 size_t l
= 0, total
= 0;
1225 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1230 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
, i
++)
1235 EXPORT_SYMBOL_GPL(of_property_count_strings
);
1237 void of_print_phandle_args(const char *msg
, const struct of_phandle_args
*args
)
1240 printk("%s %s", msg
, of_node_full_name(args
->np
));
1241 for (i
= 0; i
< args
->args_count
; i
++)
1242 printk(i
? ",%08x" : ":%08x", args
->args
[i
]);
1246 static int __of_parse_phandle_with_args(const struct device_node
*np
,
1247 const char *list_name
,
1248 const char *cells_name
,
1249 int cell_count
, int index
,
1250 struct of_phandle_args
*out_args
)
1252 const __be32
*list
, *list_end
;
1253 int rc
= 0, size
, cur_index
= 0;
1255 struct device_node
*node
= NULL
;
1258 /* Retrieve the phandle list property */
1259 list
= of_get_property(np
, list_name
, &size
);
1262 list_end
= list
+ size
/ sizeof(*list
);
1264 /* Loop over the phandles until all the requested entry is found */
1265 while (list
< list_end
) {
1270 * If phandle is 0, then it is an empty entry with no
1271 * arguments. Skip forward to the next entry.
1273 phandle
= be32_to_cpup(list
++);
1276 * Find the provider node and parse the #*-cells
1277 * property to determine the argument length.
1279 * This is not needed if the cell count is hard-coded
1280 * (i.e. cells_name not set, but cell_count is set),
1281 * except when we're going to return the found node
1284 if (cells_name
|| cur_index
== index
) {
1285 node
= of_find_node_by_phandle(phandle
);
1287 pr_err("%s: could not find phandle\n",
1294 if (of_property_read_u32(node
, cells_name
,
1296 pr_err("%s: could not get %s for %s\n",
1297 np
->full_name
, cells_name
,
1306 * Make sure that the arguments actually fit in the
1307 * remaining property data length
1309 if (list
+ count
> list_end
) {
1310 pr_err("%s: arguments longer than property\n",
1317 * All of the error cases above bail out of the loop, so at
1318 * this point, the parsing is successful. If the requested
1319 * index matches, then fill the out_args structure and return,
1320 * or return -ENOENT for an empty entry.
1323 if (cur_index
== index
) {
1329 if (WARN_ON(count
> MAX_PHANDLE_ARGS
))
1330 count
= MAX_PHANDLE_ARGS
;
1331 out_args
->np
= node
;
1332 out_args
->args_count
= count
;
1333 for (i
= 0; i
< count
; i
++)
1334 out_args
->args
[i
] = be32_to_cpup(list
++);
1339 /* Found it! return success */
1350 * Unlock node before returning result; will be one of:
1351 * -ENOENT : index is for empty phandle
1352 * -EINVAL : parsing error on data
1353 * [1..n] : Number of phandle (count mode; when index = -1)
1355 rc
= index
< 0 ? cur_index
: -ENOENT
;
1363 * of_parse_phandle - Resolve a phandle property to a device_node pointer
1364 * @np: Pointer to device node holding phandle property
1365 * @phandle_name: Name of property holding a phandle value
1366 * @index: For properties holding a table of phandles, this is the index into
1369 * Returns the device_node pointer with refcount incremented. Use
1370 * of_node_put() on it when done.
1372 struct device_node
*of_parse_phandle(const struct device_node
*np
,
1373 const char *phandle_name
, int index
)
1375 struct of_phandle_args args
;
1380 if (__of_parse_phandle_with_args(np
, phandle_name
, NULL
, 0,
1386 EXPORT_SYMBOL(of_parse_phandle
);
1389 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
1390 * @np: pointer to a device tree node containing a list
1391 * @list_name: property name that contains a list
1392 * @cells_name: property name that specifies phandles' arguments count
1393 * @index: index of a phandle to parse out
1394 * @out_args: optional pointer to output arguments structure (will be filled)
1396 * This function is useful to parse lists of phandles and their arguments.
1397 * Returns 0 on success and fills out_args, on error returns appropriate
1400 * Caller is responsible to call of_node_put() on the returned out_args->node
1406 * #list-cells = <2>;
1410 * #list-cells = <1>;
1414 * list = <&phandle1 1 2 &phandle2 3>;
1417 * To get a device_node of the `node2' node you may call this:
1418 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
1420 int of_parse_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1421 const char *cells_name
, int index
,
1422 struct of_phandle_args
*out_args
)
1426 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0,
1429 EXPORT_SYMBOL(of_parse_phandle_with_args
);
1432 * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
1433 * @np: pointer to a device tree node containing a list
1434 * @list_name: property name that contains a list
1435 * @cell_count: number of argument cells following the phandle
1436 * @index: index of a phandle to parse out
1437 * @out_args: optional pointer to output arguments structure (will be filled)
1439 * This function is useful to parse lists of phandles and their arguments.
1440 * Returns 0 on success and fills out_args, on error returns appropriate
1443 * Caller is responsible to call of_node_put() on the returned out_args->node
1455 * list = <&phandle1 0 2 &phandle2 2 3>;
1458 * To get a device_node of the `node2' node you may call this:
1459 * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
1461 int of_parse_phandle_with_fixed_args(const struct device_node
*np
,
1462 const char *list_name
, int cell_count
,
1463 int index
, struct of_phandle_args
*out_args
)
1467 return __of_parse_phandle_with_args(np
, list_name
, NULL
, cell_count
,
1470 EXPORT_SYMBOL(of_parse_phandle_with_fixed_args
);
1473 * of_count_phandle_with_args() - Find the number of phandles references in a property
1474 * @np: pointer to a device tree node containing a list
1475 * @list_name: property name that contains a list
1476 * @cells_name: property name that specifies phandles' arguments count
1478 * Returns the number of phandle + argument tuples within a property. It
1479 * is a typical pattern to encode a list of phandle and variable
1480 * arguments into a single property. The number of arguments is encoded
1481 * by a property in the phandle-target node. For example, a gpios
1482 * property would contain a list of GPIO specifies consisting of a
1483 * phandle and 1 or more arguments. The number of arguments are
1484 * determined by the #gpio-cells property in the node pointed to by the
1487 int of_count_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1488 const char *cells_name
)
1490 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0, -1,
1493 EXPORT_SYMBOL(of_count_phandle_with_args
);
1495 #if defined(CONFIG_OF_DYNAMIC)
1496 static int of_property_notify(int action
, struct device_node
*np
,
1497 struct property
*prop
)
1499 struct of_prop_reconfig pr
;
1503 return of_reconfig_notify(action
, &pr
);
1506 static int of_property_notify(int action
, struct device_node
*np
,
1507 struct property
*prop
)
1514 * of_add_property - Add a property to a node
1516 int of_add_property(struct device_node
*np
, struct property
*prop
)
1518 struct property
**next
;
1519 unsigned long flags
;
1522 rc
= of_property_notify(OF_RECONFIG_ADD_PROPERTY
, np
, prop
);
1527 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1528 next
= &np
->properties
;
1530 if (strcmp(prop
->name
, (*next
)->name
) == 0) {
1531 /* duplicate ! don't insert it */
1532 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1535 next
= &(*next
)->next
;
1538 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1540 #ifdef CONFIG_PROC_DEVICETREE
1541 /* try to add to proc as well if it was initialized */
1543 proc_device_tree_add_prop(np
->pde
, prop
);
1544 #endif /* CONFIG_PROC_DEVICETREE */
1550 * of_remove_property - Remove a property from a node.
1552 * Note that we don't actually remove it, since we have given out
1553 * who-knows-how-many pointers to the data using get-property.
1554 * Instead we just move the property to the "dead properties"
1555 * list, so it won't be found any more.
1557 int of_remove_property(struct device_node
*np
, struct property
*prop
)
1559 struct property
**next
;
1560 unsigned long flags
;
1564 rc
= of_property_notify(OF_RECONFIG_REMOVE_PROPERTY
, np
, prop
);
1568 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1569 next
= &np
->properties
;
1571 if (*next
== prop
) {
1572 /* found the node */
1574 prop
->next
= np
->deadprops
;
1575 np
->deadprops
= prop
;
1579 next
= &(*next
)->next
;
1581 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1586 #ifdef CONFIG_PROC_DEVICETREE
1587 /* try to remove the proc node as well */
1589 proc_device_tree_remove_prop(np
->pde
, prop
);
1590 #endif /* CONFIG_PROC_DEVICETREE */
1596 * of_update_property - Update a property in a node, if the property does
1597 * not exist, add it.
1599 * Note that we don't actually remove it, since we have given out
1600 * who-knows-how-many pointers to the data using get-property.
1601 * Instead we just move the property to the "dead properties" list,
1602 * and add the new property to the property list
1604 int of_update_property(struct device_node
*np
, struct property
*newprop
)
1606 struct property
**next
, *oldprop
;
1607 unsigned long flags
;
1610 rc
= of_property_notify(OF_RECONFIG_UPDATE_PROPERTY
, np
, newprop
);
1617 oldprop
= of_find_property(np
, newprop
->name
, NULL
);
1619 return of_add_property(np
, newprop
);
1621 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1622 next
= &np
->properties
;
1624 if (*next
== oldprop
) {
1625 /* found the node */
1626 newprop
->next
= oldprop
->next
;
1628 oldprop
->next
= np
->deadprops
;
1629 np
->deadprops
= oldprop
;
1633 next
= &(*next
)->next
;
1635 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1640 #ifdef CONFIG_PROC_DEVICETREE
1641 /* try to add to proc as well if it was initialized */
1643 proc_device_tree_update_prop(np
->pde
, newprop
, oldprop
);
1644 #endif /* CONFIG_PROC_DEVICETREE */
1649 #if defined(CONFIG_OF_DYNAMIC)
1651 * Support for dynamic device trees.
1653 * On some platforms, the device tree can be manipulated at runtime.
1654 * The routines in this section support adding, removing and changing
1655 * device tree nodes.
1658 static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain
);
1660 int of_reconfig_notifier_register(struct notifier_block
*nb
)
1662 return blocking_notifier_chain_register(&of_reconfig_chain
, nb
);
1664 EXPORT_SYMBOL_GPL(of_reconfig_notifier_register
);
1666 int of_reconfig_notifier_unregister(struct notifier_block
*nb
)
1668 return blocking_notifier_chain_unregister(&of_reconfig_chain
, nb
);
1670 EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister
);
1672 int of_reconfig_notify(unsigned long action
, void *p
)
1676 rc
= blocking_notifier_call_chain(&of_reconfig_chain
, action
, p
);
1677 return notifier_to_errno(rc
);
1680 #ifdef CONFIG_PROC_DEVICETREE
1681 static void of_add_proc_dt_entry(struct device_node
*dn
)
1683 struct proc_dir_entry
*ent
;
1685 ent
= proc_mkdir(strrchr(dn
->full_name
, '/') + 1, dn
->parent
->pde
);
1687 proc_device_tree_add_node(dn
, ent
);
1690 static void of_add_proc_dt_entry(struct device_node
*dn
)
1697 * of_attach_node - Plug a device node into the tree and global list.
1699 int of_attach_node(struct device_node
*np
)
1701 unsigned long flags
;
1704 rc
= of_reconfig_notify(OF_RECONFIG_ATTACH_NODE
, np
);
1708 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1709 np
->sibling
= np
->parent
->child
;
1710 np
->allnext
= of_allnodes
;
1711 np
->parent
->child
= np
;
1713 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1715 of_add_proc_dt_entry(np
);
1719 #ifdef CONFIG_PROC_DEVICETREE
1720 static void of_remove_proc_dt_entry(struct device_node
*dn
)
1722 proc_remove(dn
->pde
);
1725 static void of_remove_proc_dt_entry(struct device_node
*dn
)
1732 * of_detach_node - "Unplug" a node from the device tree.
1734 * The caller must hold a reference to the node. The memory associated with
1735 * the node is not freed until its refcount goes to zero.
1737 int of_detach_node(struct device_node
*np
)
1739 struct device_node
*parent
;
1740 unsigned long flags
;
1743 rc
= of_reconfig_notify(OF_RECONFIG_DETACH_NODE
, np
);
1747 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1749 if (of_node_check_flag(np
, OF_DETACHED
)) {
1750 /* someone already detached it */
1751 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1755 parent
= np
->parent
;
1757 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1761 if (of_allnodes
== np
)
1762 of_allnodes
= np
->allnext
;
1764 struct device_node
*prev
;
1765 for (prev
= of_allnodes
;
1766 prev
->allnext
!= np
;
1767 prev
= prev
->allnext
)
1769 prev
->allnext
= np
->allnext
;
1772 if (parent
->child
== np
)
1773 parent
->child
= np
->sibling
;
1775 struct device_node
*prevsib
;
1776 for (prevsib
= np
->parent
->child
;
1777 prevsib
->sibling
!= np
;
1778 prevsib
= prevsib
->sibling
)
1780 prevsib
->sibling
= np
->sibling
;
1783 of_node_set_flag(np
, OF_DETACHED
);
1784 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1786 of_remove_proc_dt_entry(np
);
1789 #endif /* defined(CONFIG_OF_DYNAMIC) */
1791 static void of_alias_add(struct alias_prop
*ap
, struct device_node
*np
,
1792 int id
, const char *stem
, int stem_len
)
1796 strncpy(ap
->stem
, stem
, stem_len
);
1797 ap
->stem
[stem_len
] = 0;
1798 list_add_tail(&ap
->link
, &aliases_lookup
);
1799 pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
1800 ap
->alias
, ap
->stem
, ap
->id
, of_node_full_name(np
));
1804 * of_alias_scan - Scan all properties of 'aliases' node
1806 * The function scans all the properties of 'aliases' node and populate
1807 * the the global lookup table with the properties. It returns the
1808 * number of alias_prop found, or error code in error case.
1810 * @dt_alloc: An allocator that provides a virtual address to memory
1811 * for the resulting tree
1813 void of_alias_scan(void * (*dt_alloc
)(u64 size
, u64 align
))
1815 struct property
*pp
;
1817 of_chosen
= of_find_node_by_path("/chosen");
1818 if (of_chosen
== NULL
)
1819 of_chosen
= of_find_node_by_path("/chosen@0");
1824 name
= of_get_property(of_chosen
, "linux,stdout-path", NULL
);
1826 of_stdout
= of_find_node_by_path(name
);
1829 of_aliases
= of_find_node_by_path("/aliases");
1833 for_each_property_of_node(of_aliases
, pp
) {
1834 const char *start
= pp
->name
;
1835 const char *end
= start
+ strlen(start
);
1836 struct device_node
*np
;
1837 struct alias_prop
*ap
;
1840 /* Skip those we do not want to proceed */
1841 if (!strcmp(pp
->name
, "name") ||
1842 !strcmp(pp
->name
, "phandle") ||
1843 !strcmp(pp
->name
, "linux,phandle"))
1846 np
= of_find_node_by_path(pp
->value
);
1850 /* walk the alias backwards to extract the id and work out
1851 * the 'stem' string */
1852 while (isdigit(*(end
-1)) && end
> start
)
1856 if (kstrtoint(end
, 10, &id
) < 0)
1859 /* Allocate an alias_prop with enough space for the stem */
1860 ap
= dt_alloc(sizeof(*ap
) + len
+ 1, 4);
1863 memset(ap
, 0, sizeof(*ap
) + len
+ 1);
1865 of_alias_add(ap
, np
, id
, start
, len
);
1870 * of_alias_get_id - Get alias id for the given device_node
1871 * @np: Pointer to the given device_node
1872 * @stem: Alias stem of the given device_node
1874 * The function travels the lookup table to get alias id for the given
1875 * device_node and alias stem. It returns the alias id if find it.
1877 int of_alias_get_id(struct device_node
*np
, const char *stem
)
1879 struct alias_prop
*app
;
1882 mutex_lock(&of_aliases_mutex
);
1883 list_for_each_entry(app
, &aliases_lookup
, link
) {
1884 if (strcmp(app
->stem
, stem
) != 0)
1887 if (np
== app
->np
) {
1892 mutex_unlock(&of_aliases_mutex
);
1896 EXPORT_SYMBOL_GPL(of_alias_get_id
);
1898 const __be32
*of_prop_next_u32(struct property
*prop
, const __be32
*cur
,
1901 const void *curv
= cur
;
1911 curv
+= sizeof(*cur
);
1912 if (curv
>= prop
->value
+ prop
->length
)
1916 *pu
= be32_to_cpup(curv
);
1919 EXPORT_SYMBOL_GPL(of_prop_next_u32
);
1921 const char *of_prop_next_string(struct property
*prop
, const char *cur
)
1923 const void *curv
= cur
;
1931 curv
+= strlen(cur
) + 1;
1932 if (curv
>= prop
->value
+ prop
->length
)
1937 EXPORT_SYMBOL_GPL(of_prop_next_string
);
1940 * of_device_is_stdout_path - check if a device node matches the
1941 * linux,stdout-path property
1943 * Check if this device node matches the linux,stdout-path property
1944 * in the chosen node. return true if yes, false otherwise.
1946 int of_device_is_stdout_path(struct device_node
*dn
)
1951 return of_stdout
== dn
;
1953 EXPORT_SYMBOL_GPL(of_device_is_stdout_path
);
1956 * of_find_next_cache_node - Find a node's subsidiary cache
1957 * @np: node of type "cpu" or "cache"
1959 * Returns a node pointer with refcount incremented, use
1960 * of_node_put() on it when done. Caller should hold a reference
1963 struct device_node
*of_find_next_cache_node(const struct device_node
*np
)
1965 struct device_node
*child
;
1966 const phandle
*handle
;
1968 handle
= of_get_property(np
, "l2-cache", NULL
);
1970 handle
= of_get_property(np
, "next-level-cache", NULL
);
1973 return of_find_node_by_phandle(be32_to_cpup(handle
));
1975 /* OF on pmac has nodes instead of properties named "l2-cache"
1976 * beneath CPU nodes.
1978 if (!strcmp(np
->type
, "cpu"))
1979 for_each_child_of_node(np
, child
)
1980 if (!strcmp(child
->type
, "cache"))