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/of_graph.h>
25 #include <linux/spinlock.h>
26 #include <linux/slab.h>
27 #include <linux/string.h>
28 #include <linux/proc_fs.h>
30 #include "of_private.h"
32 LIST_HEAD(aliases_lookup
);
34 struct device_node
*of_allnodes
;
35 EXPORT_SYMBOL(of_allnodes
);
36 struct device_node
*of_chosen
;
37 struct device_node
*of_aliases
;
38 static struct device_node
*of_stdout
;
40 static struct kset
*of_kset
;
43 * Used to protect the of_aliases, to hold off addition of nodes to sysfs
45 DEFINE_MUTEX(of_mutex
);
47 /* use when traversing tree through the allnext, child, sibling,
48 * or parent members of struct device_node.
50 DEFINE_RAW_SPINLOCK(devtree_lock
);
52 int of_n_addr_cells(struct device_node
*np
)
59 ip
= of_get_property(np
, "#address-cells", NULL
);
61 return be32_to_cpup(ip
);
63 /* No #address-cells property for the root node */
64 return OF_ROOT_NODE_ADDR_CELLS_DEFAULT
;
66 EXPORT_SYMBOL(of_n_addr_cells
);
68 int of_n_size_cells(struct device_node
*np
)
75 ip
= of_get_property(np
, "#size-cells", NULL
);
77 return be32_to_cpup(ip
);
79 /* No #size-cells property for the root node */
80 return OF_ROOT_NODE_SIZE_CELLS_DEFAULT
;
82 EXPORT_SYMBOL(of_n_size_cells
);
85 int __weak
of_node_to_nid(struct device_node
*np
)
87 return numa_node_id();
91 #if defined(CONFIG_OF_DYNAMIC)
93 * of_node_get - Increment refcount of a node
94 * @node: Node to inc refcount, NULL is supported to
95 * simplify writing of callers
99 struct device_node
*of_node_get(struct device_node
*node
)
102 kobject_get(&node
->kobj
);
105 EXPORT_SYMBOL(of_node_get
);
107 static inline struct device_node
*kobj_to_device_node(struct kobject
*kobj
)
109 return container_of(kobj
, struct device_node
, kobj
);
113 * of_node_release - release a dynamically allocated node
114 * @kref: kref element of the node to be released
116 * In of_node_put() this function is passed to kref_put()
119 static void of_node_release(struct kobject
*kobj
)
121 struct device_node
*node
= kobj_to_device_node(kobj
);
122 struct property
*prop
= node
->properties
;
124 /* We should never be releasing nodes that haven't been detached. */
125 if (!of_node_check_flag(node
, OF_DETACHED
)) {
126 pr_err("ERROR: Bad of_node_put() on %s\n", node
->full_name
);
131 if (!of_node_check_flag(node
, OF_DYNAMIC
))
135 struct property
*next
= prop
->next
;
142 prop
= node
->deadprops
;
143 node
->deadprops
= NULL
;
146 kfree(node
->full_name
);
152 * of_node_put - Decrement refcount of a node
153 * @node: Node to dec refcount, NULL is supported to
154 * simplify writing of callers
157 void of_node_put(struct device_node
*node
)
160 kobject_put(&node
->kobj
);
162 EXPORT_SYMBOL(of_node_put
);
164 static void of_node_release(struct kobject
*kobj
)
166 /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
168 #endif /* CONFIG_OF_DYNAMIC */
170 struct kobj_type of_node_ktype
= {
171 .release
= of_node_release
,
174 static ssize_t
of_node_property_read(struct file
*filp
, struct kobject
*kobj
,
175 struct bin_attribute
*bin_attr
, char *buf
,
176 loff_t offset
, size_t count
)
178 struct property
*pp
= container_of(bin_attr
, struct property
, attr
);
179 return memory_read_from_buffer(buf
, count
, &offset
, pp
->value
, pp
->length
);
182 static const char *safe_name(struct kobject
*kobj
, const char *orig_name
)
184 const char *name
= orig_name
;
185 struct kernfs_node
*kn
;
188 /* don't be a hero. After 16 tries give up */
189 while (i
< 16 && (kn
= sysfs_get_dirent(kobj
->sd
, name
))) {
191 if (name
!= orig_name
)
193 name
= kasprintf(GFP_KERNEL
, "%s#%i", orig_name
, ++i
);
196 if (name
!= orig_name
)
197 pr_warn("device-tree: Duplicate name in %s, renamed to \"%s\"\n",
198 kobject_name(kobj
), name
);
202 static int __of_add_property_sysfs(struct device_node
*np
, struct property
*pp
)
206 /* Important: Don't leak passwords */
207 bool secure
= strncmp(pp
->name
, "security-", 9) == 0;
209 sysfs_bin_attr_init(&pp
->attr
);
210 pp
->attr
.attr
.name
= safe_name(&np
->kobj
, pp
->name
);
211 pp
->attr
.attr
.mode
= secure
? S_IRUSR
: S_IRUGO
;
212 pp
->attr
.size
= secure
? 0 : pp
->length
;
213 pp
->attr
.read
= of_node_property_read
;
215 rc
= sysfs_create_bin_file(&np
->kobj
, &pp
->attr
);
216 WARN(rc
, "error adding attribute %s to node %s\n", pp
->name
, np
->full_name
);
220 static int __of_node_add(struct device_node
*np
)
226 np
->kobj
.kset
= of_kset
;
228 /* Nodes without parents are new top level trees */
229 rc
= kobject_add(&np
->kobj
, NULL
, "%s",
230 safe_name(&of_kset
->kobj
, "base"));
232 name
= safe_name(&np
->parent
->kobj
, kbasename(np
->full_name
));
233 if (!name
|| !name
[0])
236 rc
= kobject_add(&np
->kobj
, &np
->parent
->kobj
, "%s", name
);
241 for_each_property_of_node(np
, pp
)
242 __of_add_property_sysfs(np
, pp
);
247 int of_node_add(struct device_node
*np
)
251 BUG_ON(!of_node_is_initialized(np
));
254 * Grab the mutex here so that in a race condition between of_init() and
255 * of_node_add(), node addition will still be consistent.
257 mutex_lock(&of_mutex
);
259 rc
= __of_node_add(np
);
261 /* This scenario may be perfectly valid, but report it anyway */
262 pr_info("of_node_add(%s) before of_init()\n", np
->full_name
);
263 mutex_unlock(&of_mutex
);
267 #if defined(CONFIG_OF_DYNAMIC)
268 static void of_node_remove(struct device_node
*np
)
272 BUG_ON(!of_node_is_initialized(np
));
274 /* only remove properties if on sysfs */
275 if (of_node_is_attached(np
)) {
276 for_each_property_of_node(np
, pp
)
277 sysfs_remove_bin_file(&np
->kobj
, &pp
->attr
);
278 kobject_del(&np
->kobj
);
281 /* finally remove the kobj_init ref */
286 static int __init
of_init(void)
288 struct device_node
*np
;
290 /* Create the kset, and register existing nodes */
291 mutex_lock(&of_mutex
);
292 of_kset
= kset_create_and_add("devicetree", NULL
, firmware_kobj
);
294 mutex_unlock(&of_mutex
);
297 for_each_of_allnodes(np
)
299 mutex_unlock(&of_mutex
);
301 /* Symlink in /proc as required by userspace ABI */
303 proc_symlink("device-tree", NULL
, "/sys/firmware/devicetree/base");
307 core_initcall(of_init
);
309 static struct property
*__of_find_property(const struct device_node
*np
,
310 const char *name
, int *lenp
)
317 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
318 if (of_prop_cmp(pp
->name
, name
) == 0) {
328 struct property
*of_find_property(const struct device_node
*np
,
335 raw_spin_lock_irqsave(&devtree_lock
, flags
);
336 pp
= __of_find_property(np
, name
, lenp
);
337 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
341 EXPORT_SYMBOL(of_find_property
);
344 * of_find_all_nodes - Get next node in global list
345 * @prev: Previous node or NULL to start iteration
346 * of_node_put() will be called on it
348 * Returns a node pointer with refcount incremented, use
349 * of_node_put() on it when done.
351 struct device_node
*of_find_all_nodes(struct device_node
*prev
)
353 struct device_node
*np
;
356 raw_spin_lock_irqsave(&devtree_lock
, flags
);
357 np
= prev
? prev
->allnext
: of_allnodes
;
358 for (; np
!= NULL
; np
= np
->allnext
)
362 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
365 EXPORT_SYMBOL(of_find_all_nodes
);
368 * Find a property with a given name for a given node
369 * and return the value.
371 static const void *__of_get_property(const struct device_node
*np
,
372 const char *name
, int *lenp
)
374 struct property
*pp
= __of_find_property(np
, name
, lenp
);
376 return pp
? pp
->value
: NULL
;
380 * Find a property with a given name for a given node
381 * and return the value.
383 const void *of_get_property(const struct device_node
*np
, const char *name
,
386 struct property
*pp
= of_find_property(np
, name
, lenp
);
388 return pp
? pp
->value
: NULL
;
390 EXPORT_SYMBOL(of_get_property
);
393 * arch_match_cpu_phys_id - Match the given logical CPU and physical id
395 * @cpu: logical cpu index of a core/thread
396 * @phys_id: physical identifier of a core/thread
398 * CPU logical to physical index mapping is architecture specific.
399 * However this __weak function provides a default match of physical
400 * id to logical cpu index. phys_id provided here is usually values read
401 * from the device tree which must match the hardware internal registers.
403 * Returns true if the physical identifier and the logical cpu index
404 * correspond to the same core/thread, false otherwise.
406 bool __weak
arch_match_cpu_phys_id(int cpu
, u64 phys_id
)
408 return (u32
)phys_id
== cpu
;
412 * Checks if the given "prop_name" property holds the physical id of the
413 * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
414 * NULL, local thread number within the core is returned in it.
416 static bool __of_find_n_match_cpu_property(struct device_node
*cpun
,
417 const char *prop_name
, int cpu
, unsigned int *thread
)
420 int ac
, prop_len
, tid
;
423 ac
= of_n_addr_cells(cpun
);
424 cell
= of_get_property(cpun
, prop_name
, &prop_len
);
427 prop_len
/= sizeof(*cell
) * ac
;
428 for (tid
= 0; tid
< prop_len
; tid
++) {
429 hwid
= of_read_number(cell
, ac
);
430 if (arch_match_cpu_phys_id(cpu
, hwid
)) {
441 * arch_find_n_match_cpu_physical_id - See if the given device node is
442 * for the cpu corresponding to logical cpu 'cpu'. Return true if so,
443 * else false. If 'thread' is non-NULL, the local thread number within the
444 * core is returned in it.
446 bool __weak
arch_find_n_match_cpu_physical_id(struct device_node
*cpun
,
447 int cpu
, unsigned int *thread
)
449 /* Check for non-standard "ibm,ppc-interrupt-server#s" property
450 * for thread ids on PowerPC. If it doesn't exist fallback to
451 * standard "reg" property.
453 if (IS_ENABLED(CONFIG_PPC
) &&
454 __of_find_n_match_cpu_property(cpun
,
455 "ibm,ppc-interrupt-server#s",
459 if (__of_find_n_match_cpu_property(cpun
, "reg", cpu
, thread
))
466 * of_get_cpu_node - Get device node associated with the given logical CPU
468 * @cpu: CPU number(logical index) for which device node is required
469 * @thread: if not NULL, local thread number within the physical core is
472 * The main purpose of this function is to retrieve the device node for the
473 * given logical CPU index. It should be used to initialize the of_node in
474 * cpu device. Once of_node in cpu device is populated, all the further
475 * references can use that instead.
477 * CPU logical to physical index mapping is architecture specific and is built
478 * before booting secondary cores. This function uses arch_match_cpu_phys_id
479 * which can be overridden by architecture specific implementation.
481 * Returns a node pointer for the logical cpu if found, else NULL.
483 struct device_node
*of_get_cpu_node(int cpu
, unsigned int *thread
)
485 struct device_node
*cpun
;
487 for_each_node_by_type(cpun
, "cpu") {
488 if (arch_find_n_match_cpu_physical_id(cpun
, cpu
, thread
))
493 EXPORT_SYMBOL(of_get_cpu_node
);
496 * __of_device_is_compatible() - Check if the node matches given constraints
497 * @device: pointer to node
498 * @compat: required compatible string, NULL or "" for any match
499 * @type: required device_type value, NULL or "" for any match
500 * @name: required node name, NULL or "" for any match
502 * Checks if the given @compat, @type and @name strings match the
503 * properties of the given @device. A constraints can be skipped by
504 * passing NULL or an empty string as the constraint.
506 * Returns 0 for no match, and a positive integer on match. The return
507 * value is a relative score with larger values indicating better
508 * matches. The score is weighted for the most specific compatible value
509 * to get the highest score. Matching type is next, followed by matching
510 * name. Practically speaking, this results in the following priority
513 * 1. specific compatible && type && name
514 * 2. specific compatible && type
515 * 3. specific compatible && name
516 * 4. specific compatible
517 * 5. general compatible && type && name
518 * 6. general compatible && type
519 * 7. general compatible && name
520 * 8. general compatible
525 static int __of_device_is_compatible(const struct device_node
*device
,
526 const char *compat
, const char *type
, const char *name
)
528 struct property
*prop
;
530 int index
= 0, score
= 0;
532 /* Compatible match has highest priority */
533 if (compat
&& compat
[0]) {
534 prop
= __of_find_property(device
, "compatible", NULL
);
535 for (cp
= of_prop_next_string(prop
, NULL
); cp
;
536 cp
= of_prop_next_string(prop
, cp
), index
++) {
537 if (of_compat_cmp(cp
, compat
, strlen(compat
)) == 0) {
538 score
= INT_MAX
/2 - (index
<< 2);
546 /* Matching type is better than matching name */
547 if (type
&& type
[0]) {
548 if (!device
->type
|| of_node_cmp(type
, device
->type
))
553 /* Matching name is a bit better than not */
554 if (name
&& name
[0]) {
555 if (!device
->name
|| of_node_cmp(name
, device
->name
))
563 /** Checks if the given "compat" string matches one of the strings in
564 * the device's "compatible" property
566 int of_device_is_compatible(const struct device_node
*device
,
572 raw_spin_lock_irqsave(&devtree_lock
, flags
);
573 res
= __of_device_is_compatible(device
, compat
, NULL
, NULL
);
574 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
577 EXPORT_SYMBOL(of_device_is_compatible
);
580 * of_machine_is_compatible - Test root of device tree for a given compatible value
581 * @compat: compatible string to look for in root node's compatible property.
583 * Returns true if the root node has the given value in its
584 * compatible property.
586 int of_machine_is_compatible(const char *compat
)
588 struct device_node
*root
;
591 root
= of_find_node_by_path("/");
593 rc
= of_device_is_compatible(root
, compat
);
598 EXPORT_SYMBOL(of_machine_is_compatible
);
601 * __of_device_is_available - check if a device is available for use
603 * @device: Node to check for availability, with locks already held
605 * Returns 1 if the status property is absent or set to "okay" or "ok",
608 static int __of_device_is_available(const struct device_node
*device
)
616 status
= __of_get_property(device
, "status", &statlen
);
621 if (!strcmp(status
, "okay") || !strcmp(status
, "ok"))
629 * of_device_is_available - check if a device is available for use
631 * @device: Node to check for availability
633 * Returns 1 if the status property is absent or set to "okay" or "ok",
636 int of_device_is_available(const struct device_node
*device
)
641 raw_spin_lock_irqsave(&devtree_lock
, flags
);
642 res
= __of_device_is_available(device
);
643 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
647 EXPORT_SYMBOL(of_device_is_available
);
650 * of_get_parent - Get a node's parent if any
651 * @node: Node to get parent
653 * Returns a node pointer with refcount incremented, use
654 * of_node_put() on it when done.
656 struct device_node
*of_get_parent(const struct device_node
*node
)
658 struct device_node
*np
;
664 raw_spin_lock_irqsave(&devtree_lock
, flags
);
665 np
= of_node_get(node
->parent
);
666 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
669 EXPORT_SYMBOL(of_get_parent
);
672 * of_get_next_parent - Iterate to a node's parent
673 * @node: Node to get parent of
675 * This is like of_get_parent() except that it drops the
676 * refcount on the passed node, making it suitable for iterating
677 * through a node's parents.
679 * Returns a node pointer with refcount incremented, use
680 * of_node_put() on it when done.
682 struct device_node
*of_get_next_parent(struct device_node
*node
)
684 struct device_node
*parent
;
690 raw_spin_lock_irqsave(&devtree_lock
, flags
);
691 parent
= of_node_get(node
->parent
);
693 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
696 EXPORT_SYMBOL(of_get_next_parent
);
698 static struct device_node
*__of_get_next_child(const struct device_node
*node
,
699 struct device_node
*prev
)
701 struct device_node
*next
;
706 next
= prev
? prev
->sibling
: node
->child
;
707 for (; next
; next
= next
->sibling
)
708 if (of_node_get(next
))
713 #define __for_each_child_of_node(parent, child) \
714 for (child = __of_get_next_child(parent, NULL); child != NULL; \
715 child = __of_get_next_child(parent, child))
718 * of_get_next_child - Iterate a node childs
720 * @prev: previous child of the parent node, or NULL to get first
722 * Returns a node pointer with refcount incremented, use
723 * of_node_put() on it when done.
725 struct device_node
*of_get_next_child(const struct device_node
*node
,
726 struct device_node
*prev
)
728 struct device_node
*next
;
731 raw_spin_lock_irqsave(&devtree_lock
, flags
);
732 next
= __of_get_next_child(node
, prev
);
733 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
736 EXPORT_SYMBOL(of_get_next_child
);
739 * of_get_next_available_child - Find the next available child node
741 * @prev: previous child of the parent node, or NULL to get first
743 * This function is like of_get_next_child(), except that it
744 * automatically skips any disabled nodes (i.e. status = "disabled").
746 struct device_node
*of_get_next_available_child(const struct device_node
*node
,
747 struct device_node
*prev
)
749 struct device_node
*next
;
755 raw_spin_lock_irqsave(&devtree_lock
, flags
);
756 next
= prev
? prev
->sibling
: node
->child
;
757 for (; next
; next
= next
->sibling
) {
758 if (!__of_device_is_available(next
))
760 if (of_node_get(next
))
764 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
767 EXPORT_SYMBOL(of_get_next_available_child
);
770 * of_get_child_by_name - Find the child node by name for a given parent
772 * @name: child name to look for.
774 * This function looks for child node for given matching name
776 * Returns a node pointer if found, with refcount incremented, use
777 * of_node_put() on it when done.
778 * Returns NULL if node is not found.
780 struct device_node
*of_get_child_by_name(const struct device_node
*node
,
783 struct device_node
*child
;
785 for_each_child_of_node(node
, child
)
786 if (child
->name
&& (of_node_cmp(child
->name
, name
) == 0))
790 EXPORT_SYMBOL(of_get_child_by_name
);
792 static struct device_node
*__of_find_node_by_path(struct device_node
*parent
,
795 struct device_node
*child
;
796 int len
= strchrnul(path
, '/') - path
;
801 __for_each_child_of_node(parent
, child
) {
802 const char *name
= strrchr(child
->full_name
, '/');
803 if (WARN(!name
, "malformed device_node %s\n", child
->full_name
))
806 if (strncmp(path
, name
, len
) == 0 && (strlen(name
) == len
))
813 * of_find_node_by_path - Find a node matching a full OF path
814 * @path: Either the full path to match, or if the path does not
815 * start with '/', the name of a property of the /aliases
816 * node (an alias). In the case of an alias, the node
817 * matching the alias' value will be returned.
822 * foo/bar Valid alias + relative path
824 * Returns a node pointer with refcount incremented, use
825 * of_node_put() on it when done.
827 struct device_node
*of_find_node_by_path(const char *path
)
829 struct device_node
*np
= NULL
;
833 if (strcmp(path
, "/") == 0)
834 return of_node_get(of_allnodes
);
836 /* The path could begin with an alias */
838 char *p
= strchrnul(path
, '/');
841 /* of_aliases must not be NULL */
845 for_each_property_of_node(of_aliases
, pp
) {
846 if (strlen(pp
->name
) == len
&& !strncmp(pp
->name
, path
, len
)) {
847 np
= of_find_node_by_path(pp
->value
);
856 /* Step down the tree matching path components */
857 raw_spin_lock_irqsave(&devtree_lock
, flags
);
859 np
= of_node_get(of_allnodes
);
860 while (np
&& *path
== '/') {
861 path
++; /* Increment past '/' delimiter */
862 np
= __of_find_node_by_path(np
, path
);
863 path
= strchrnul(path
, '/');
865 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
868 EXPORT_SYMBOL(of_find_node_by_path
);
871 * of_find_node_by_name - Find a node by its "name" property
872 * @from: The node to start searching from or NULL, the node
873 * you pass will not be searched, only the next one
874 * will; typically, you pass what the previous call
875 * returned. of_node_put() will be called on it
876 * @name: The name string to match against
878 * Returns a node pointer with refcount incremented, use
879 * of_node_put() on it when done.
881 struct device_node
*of_find_node_by_name(struct device_node
*from
,
884 struct device_node
*np
;
887 raw_spin_lock_irqsave(&devtree_lock
, flags
);
888 np
= from
? from
->allnext
: of_allnodes
;
889 for (; np
; np
= np
->allnext
)
890 if (np
->name
&& (of_node_cmp(np
->name
, name
) == 0)
894 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
897 EXPORT_SYMBOL(of_find_node_by_name
);
900 * of_find_node_by_type - Find a node by its "device_type" property
901 * @from: The node to start searching from, or NULL to start searching
902 * the entire device tree. The node you pass will not be
903 * searched, only the next one will; typically, you pass
904 * what the previous call returned. of_node_put() will be
905 * called on from for you.
906 * @type: The type string to match against
908 * Returns a node pointer with refcount incremented, use
909 * of_node_put() on it when done.
911 struct device_node
*of_find_node_by_type(struct device_node
*from
,
914 struct device_node
*np
;
917 raw_spin_lock_irqsave(&devtree_lock
, flags
);
918 np
= from
? from
->allnext
: of_allnodes
;
919 for (; np
; np
= np
->allnext
)
920 if (np
->type
&& (of_node_cmp(np
->type
, type
) == 0)
924 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
927 EXPORT_SYMBOL(of_find_node_by_type
);
930 * of_find_compatible_node - Find a node based on type and one of the
931 * tokens in its "compatible" property
932 * @from: The node to start searching from or NULL, the node
933 * you pass will not be searched, only the next one
934 * will; typically, you pass what the previous call
935 * returned. of_node_put() will be called on it
936 * @type: The type string to match "device_type" or NULL to ignore
937 * @compatible: The string to match to one of the tokens in the device
940 * Returns a node pointer with refcount incremented, use
941 * of_node_put() on it when done.
943 struct device_node
*of_find_compatible_node(struct device_node
*from
,
944 const char *type
, const char *compatible
)
946 struct device_node
*np
;
949 raw_spin_lock_irqsave(&devtree_lock
, flags
);
950 np
= from
? from
->allnext
: of_allnodes
;
951 for (; np
; np
= np
->allnext
) {
952 if (__of_device_is_compatible(np
, compatible
, type
, NULL
) &&
957 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
960 EXPORT_SYMBOL(of_find_compatible_node
);
963 * of_find_node_with_property - Find a node which has a property with
965 * @from: The node to start searching from or NULL, the node
966 * you pass will not be searched, only the next one
967 * will; typically, you pass what the previous call
968 * returned. of_node_put() will be called on it
969 * @prop_name: The name of the property to look for.
971 * Returns a node pointer with refcount incremented, use
972 * of_node_put() on it when done.
974 struct device_node
*of_find_node_with_property(struct device_node
*from
,
975 const char *prop_name
)
977 struct device_node
*np
;
981 raw_spin_lock_irqsave(&devtree_lock
, flags
);
982 np
= from
? from
->allnext
: of_allnodes
;
983 for (; np
; np
= np
->allnext
) {
984 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
985 if (of_prop_cmp(pp
->name
, prop_name
) == 0) {
993 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
996 EXPORT_SYMBOL(of_find_node_with_property
);
999 const struct of_device_id
*__of_match_node(const struct of_device_id
*matches
,
1000 const struct device_node
*node
)
1002 const struct of_device_id
*best_match
= NULL
;
1003 int score
, best_score
= 0;
1008 for (; matches
->name
[0] || matches
->type
[0] || matches
->compatible
[0]; matches
++) {
1009 score
= __of_device_is_compatible(node
, matches
->compatible
,
1010 matches
->type
, matches
->name
);
1011 if (score
> best_score
) {
1012 best_match
= matches
;
1021 * of_match_node - Tell if an device_node has a matching of_match structure
1022 * @matches: array of of device match structures to search in
1023 * @node: the of device structure to match against
1025 * Low level utility function used by device matching.
1027 const struct of_device_id
*of_match_node(const struct of_device_id
*matches
,
1028 const struct device_node
*node
)
1030 const struct of_device_id
*match
;
1031 unsigned long flags
;
1033 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1034 match
= __of_match_node(matches
, node
);
1035 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1038 EXPORT_SYMBOL(of_match_node
);
1041 * of_find_matching_node_and_match - Find a node based on an of_device_id
1043 * @from: The node to start searching from or NULL, the node
1044 * you pass will not be searched, only the next one
1045 * will; typically, you pass what the previous call
1046 * returned. of_node_put() will be called on it
1047 * @matches: array of of device match structures to search in
1048 * @match Updated to point at the matches entry which matched
1050 * Returns a node pointer with refcount incremented, use
1051 * of_node_put() on it when done.
1053 struct device_node
*of_find_matching_node_and_match(struct device_node
*from
,
1054 const struct of_device_id
*matches
,
1055 const struct of_device_id
**match
)
1057 struct device_node
*np
;
1058 const struct of_device_id
*m
;
1059 unsigned long flags
;
1064 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1065 np
= from
? from
->allnext
: of_allnodes
;
1066 for (; np
; np
= np
->allnext
) {
1067 m
= __of_match_node(matches
, np
);
1068 if (m
&& of_node_get(np
)) {
1075 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1078 EXPORT_SYMBOL(of_find_matching_node_and_match
);
1081 * of_modalias_node - Lookup appropriate modalias for a device node
1082 * @node: pointer to a device tree node
1083 * @modalias: Pointer to buffer that modalias value will be copied into
1084 * @len: Length of modalias value
1086 * Based on the value of the compatible property, this routine will attempt
1087 * to choose an appropriate modalias value for a particular device tree node.
1088 * It does this by stripping the manufacturer prefix (as delimited by a ',')
1089 * from the first entry in the compatible list property.
1091 * This routine returns 0 on success, <0 on failure.
1093 int of_modalias_node(struct device_node
*node
, char *modalias
, int len
)
1095 const char *compatible
, *p
;
1098 compatible
= of_get_property(node
, "compatible", &cplen
);
1099 if (!compatible
|| strlen(compatible
) > cplen
)
1101 p
= strchr(compatible
, ',');
1102 strlcpy(modalias
, p
? p
+ 1 : compatible
, len
);
1105 EXPORT_SYMBOL_GPL(of_modalias_node
);
1108 * of_find_node_by_phandle - Find a node given a phandle
1109 * @handle: phandle of the node to find
1111 * Returns a node pointer with refcount incremented, use
1112 * of_node_put() on it when done.
1114 struct device_node
*of_find_node_by_phandle(phandle handle
)
1116 struct device_node
*np
;
1117 unsigned long flags
;
1119 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1120 for (np
= of_allnodes
; np
; np
= np
->allnext
)
1121 if (np
->phandle
== handle
)
1124 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1127 EXPORT_SYMBOL(of_find_node_by_phandle
);
1130 * of_property_count_elems_of_size - Count the number of elements in a property
1132 * @np: device node from which the property value is to be read.
1133 * @propname: name of the property to be searched.
1134 * @elem_size: size of the individual element
1136 * Search for a property in a device node and count the number of elements of
1137 * size elem_size in it. Returns number of elements on sucess, -EINVAL if the
1138 * property does not exist or its length does not match a multiple of elem_size
1139 * and -ENODATA if the property does not have a value.
1141 int of_property_count_elems_of_size(const struct device_node
*np
,
1142 const char *propname
, int elem_size
)
1144 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1151 if (prop
->length
% elem_size
!= 0) {
1152 pr_err("size of %s in node %s is not a multiple of %d\n",
1153 propname
, np
->full_name
, elem_size
);
1157 return prop
->length
/ elem_size
;
1159 EXPORT_SYMBOL_GPL(of_property_count_elems_of_size
);
1162 * of_find_property_value_of_size
1164 * @np: device node from which the property value is to be read.
1165 * @propname: name of the property to be searched.
1166 * @len: requested length of property value
1168 * Search for a property in a device node and valid the requested size.
1169 * Returns the property value on success, -EINVAL if the property does not
1170 * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
1171 * property data isn't large enough.
1174 static void *of_find_property_value_of_size(const struct device_node
*np
,
1175 const char *propname
, u32 len
)
1177 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1180 return ERR_PTR(-EINVAL
);
1182 return ERR_PTR(-ENODATA
);
1183 if (len
> prop
->length
)
1184 return ERR_PTR(-EOVERFLOW
);
1190 * of_property_read_u32_index - Find and read a u32 from a multi-value property.
1192 * @np: device node from which the property value is to be read.
1193 * @propname: name of the property to be searched.
1194 * @index: index of the u32 in the list of values
1195 * @out_value: pointer to return value, modified only if no error.
1197 * Search for a property in a device node and read nth 32-bit value from
1198 * it. Returns 0 on success, -EINVAL if the property does not exist,
1199 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1200 * property data isn't large enough.
1202 * The out_value is modified only if a valid u32 value can be decoded.
1204 int of_property_read_u32_index(const struct device_node
*np
,
1205 const char *propname
,
1206 u32 index
, u32
*out_value
)
1208 const u32
*val
= of_find_property_value_of_size(np
, propname
,
1209 ((index
+ 1) * sizeof(*out_value
)));
1212 return PTR_ERR(val
);
1214 *out_value
= be32_to_cpup(((__be32
*)val
) + index
);
1217 EXPORT_SYMBOL_GPL(of_property_read_u32_index
);
1220 * of_property_read_u8_array - Find and read an array of u8 from a property.
1222 * @np: device node from which the property value is to be read.
1223 * @propname: name of the property to be searched.
1224 * @out_values: pointer to return value, modified only if return value is 0.
1225 * @sz: number of array elements to read
1227 * Search for a property in a device node and read 8-bit value(s) from
1228 * it. Returns 0 on success, -EINVAL if the property does not exist,
1229 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1230 * property data isn't large enough.
1232 * dts entry of array should be like:
1233 * property = /bits/ 8 <0x50 0x60 0x70>;
1235 * The out_values is modified only if a valid u8 value can be decoded.
1237 int of_property_read_u8_array(const struct device_node
*np
,
1238 const char *propname
, u8
*out_values
, size_t sz
)
1240 const u8
*val
= of_find_property_value_of_size(np
, propname
,
1241 (sz
* sizeof(*out_values
)));
1244 return PTR_ERR(val
);
1247 *out_values
++ = *val
++;
1250 EXPORT_SYMBOL_GPL(of_property_read_u8_array
);
1253 * of_property_read_u16_array - Find and read an array of u16 from a property.
1255 * @np: device node from which the property value is to be read.
1256 * @propname: name of the property to be searched.
1257 * @out_values: pointer to return value, modified only if return value is 0.
1258 * @sz: number of array elements to read
1260 * Search for a property in a device node and read 16-bit value(s) from
1261 * it. Returns 0 on success, -EINVAL if the property does not exist,
1262 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1263 * property data isn't large enough.
1265 * dts entry of array should be like:
1266 * property = /bits/ 16 <0x5000 0x6000 0x7000>;
1268 * The out_values is modified only if a valid u16 value can be decoded.
1270 int of_property_read_u16_array(const struct device_node
*np
,
1271 const char *propname
, u16
*out_values
, size_t sz
)
1273 const __be16
*val
= of_find_property_value_of_size(np
, propname
,
1274 (sz
* sizeof(*out_values
)));
1277 return PTR_ERR(val
);
1280 *out_values
++ = be16_to_cpup(val
++);
1283 EXPORT_SYMBOL_GPL(of_property_read_u16_array
);
1286 * of_property_read_u32_array - Find and read an array of 32 bit integers
1289 * @np: device node from which the property value is to be read.
1290 * @propname: name of the property to be searched.
1291 * @out_values: pointer to return value, modified only if return value is 0.
1292 * @sz: number of array elements to read
1294 * Search for a property in a device node and read 32-bit value(s) from
1295 * it. Returns 0 on success, -EINVAL if the property does not exist,
1296 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1297 * property data isn't large enough.
1299 * The out_values is modified only if a valid u32 value can be decoded.
1301 int of_property_read_u32_array(const struct device_node
*np
,
1302 const char *propname
, u32
*out_values
,
1305 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1306 (sz
* sizeof(*out_values
)));
1309 return PTR_ERR(val
);
1312 *out_values
++ = be32_to_cpup(val
++);
1315 EXPORT_SYMBOL_GPL(of_property_read_u32_array
);
1318 * of_property_read_u64 - Find and read a 64 bit integer from a property
1319 * @np: device node from which the property value is to be read.
1320 * @propname: name of the property to be searched.
1321 * @out_value: pointer to return value, modified only if return value is 0.
1323 * Search for a property in a device node and read a 64-bit value from
1324 * it. Returns 0 on success, -EINVAL if the property does not exist,
1325 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1326 * property data isn't large enough.
1328 * The out_value is modified only if a valid u64 value can be decoded.
1330 int of_property_read_u64(const struct device_node
*np
, const char *propname
,
1333 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1334 sizeof(*out_value
));
1337 return PTR_ERR(val
);
1339 *out_value
= of_read_number(val
, 2);
1342 EXPORT_SYMBOL_GPL(of_property_read_u64
);
1345 * of_property_read_string - Find and read a string from a property
1346 * @np: device node from which the property value is to be read.
1347 * @propname: name of the property to be searched.
1348 * @out_string: pointer to null terminated return string, modified only if
1349 * return value is 0.
1351 * Search for a property in a device tree node and retrieve a null
1352 * terminated string value (pointer to data, not a copy). Returns 0 on
1353 * success, -EINVAL if the property does not exist, -ENODATA if property
1354 * does not have a value, and -EILSEQ if the string is not null-terminated
1355 * within the length of the property data.
1357 * The out_string pointer is modified only if a valid string can be decoded.
1359 int of_property_read_string(struct device_node
*np
, const char *propname
,
1360 const char **out_string
)
1362 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1367 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1369 *out_string
= prop
->value
;
1372 EXPORT_SYMBOL_GPL(of_property_read_string
);
1375 * of_property_read_string_index - Find and read a string from a multiple
1377 * @np: device node from which the property value is to be read.
1378 * @propname: name of the property to be searched.
1379 * @index: index of the string in the list of strings
1380 * @out_string: pointer to null terminated return string, modified only if
1381 * return value is 0.
1383 * Search for a property in a device tree node and retrieve a null
1384 * terminated string value (pointer to data, not a copy) in the list of strings
1385 * contained in that property.
1386 * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
1387 * property does not have a value, and -EILSEQ if the string is not
1388 * null-terminated within the length of the property data.
1390 * The out_string pointer is modified only if a valid string can be decoded.
1392 int of_property_read_string_index(struct device_node
*np
, const char *propname
,
1393 int index
, const char **output
)
1395 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1397 size_t l
= 0, total
= 0;
1404 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1409 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
) {
1418 EXPORT_SYMBOL_GPL(of_property_read_string_index
);
1421 * of_property_match_string() - Find string in a list and return index
1422 * @np: pointer to node containing string list property
1423 * @propname: string list property name
1424 * @string: pointer to string to search for in string list
1426 * This function searches a string list property and returns the index
1427 * of a specific string value.
1429 int of_property_match_string(struct device_node
*np
, const char *propname
,
1432 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1435 const char *p
, *end
;
1443 end
= p
+ prop
->length
;
1445 for (i
= 0; p
< end
; i
++, p
+= l
) {
1449 pr_debug("comparing %s with %s\n", string
, p
);
1450 if (strcmp(string
, p
) == 0)
1451 return i
; /* Found it; return index */
1455 EXPORT_SYMBOL_GPL(of_property_match_string
);
1458 * of_property_count_strings - Find and return the number of strings from a
1459 * multiple strings property.
1460 * @np: device node from which the property value is to be read.
1461 * @propname: name of the property to be searched.
1463 * Search for a property in a device tree node and retrieve the number of null
1464 * terminated string contain in it. Returns the number of strings on
1465 * success, -EINVAL if the property does not exist, -ENODATA if property
1466 * does not have a value, and -EILSEQ if the string is not null-terminated
1467 * within the length of the property data.
1469 int of_property_count_strings(struct device_node
*np
, const char *propname
)
1471 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1473 size_t l
= 0, total
= 0;
1480 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1485 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
, i
++)
1490 EXPORT_SYMBOL_GPL(of_property_count_strings
);
1492 void of_print_phandle_args(const char *msg
, const struct of_phandle_args
*args
)
1495 printk("%s %s", msg
, of_node_full_name(args
->np
));
1496 for (i
= 0; i
< args
->args_count
; i
++)
1497 printk(i
? ",%08x" : ":%08x", args
->args
[i
]);
1501 static int __of_parse_phandle_with_args(const struct device_node
*np
,
1502 const char *list_name
,
1503 const char *cells_name
,
1504 int cell_count
, int index
,
1505 struct of_phandle_args
*out_args
)
1507 const __be32
*list
, *list_end
;
1508 int rc
= 0, size
, cur_index
= 0;
1510 struct device_node
*node
= NULL
;
1513 /* Retrieve the phandle list property */
1514 list
= of_get_property(np
, list_name
, &size
);
1517 list_end
= list
+ size
/ sizeof(*list
);
1519 /* Loop over the phandles until all the requested entry is found */
1520 while (list
< list_end
) {
1525 * If phandle is 0, then it is an empty entry with no
1526 * arguments. Skip forward to the next entry.
1528 phandle
= be32_to_cpup(list
++);
1531 * Find the provider node and parse the #*-cells
1532 * property to determine the argument length.
1534 * This is not needed if the cell count is hard-coded
1535 * (i.e. cells_name not set, but cell_count is set),
1536 * except when we're going to return the found node
1539 if (cells_name
|| cur_index
== index
) {
1540 node
= of_find_node_by_phandle(phandle
);
1542 pr_err("%s: could not find phandle\n",
1549 if (of_property_read_u32(node
, cells_name
,
1551 pr_err("%s: could not get %s for %s\n",
1552 np
->full_name
, cells_name
,
1561 * Make sure that the arguments actually fit in the
1562 * remaining property data length
1564 if (list
+ count
> list_end
) {
1565 pr_err("%s: arguments longer than property\n",
1572 * All of the error cases above bail out of the loop, so at
1573 * this point, the parsing is successful. If the requested
1574 * index matches, then fill the out_args structure and return,
1575 * or return -ENOENT for an empty entry.
1578 if (cur_index
== index
) {
1584 if (WARN_ON(count
> MAX_PHANDLE_ARGS
))
1585 count
= MAX_PHANDLE_ARGS
;
1586 out_args
->np
= node
;
1587 out_args
->args_count
= count
;
1588 for (i
= 0; i
< count
; i
++)
1589 out_args
->args
[i
] = be32_to_cpup(list
++);
1594 /* Found it! return success */
1605 * Unlock node before returning result; will be one of:
1606 * -ENOENT : index is for empty phandle
1607 * -EINVAL : parsing error on data
1608 * [1..n] : Number of phandle (count mode; when index = -1)
1610 rc
= index
< 0 ? cur_index
: -ENOENT
;
1618 * of_parse_phandle - Resolve a phandle property to a device_node pointer
1619 * @np: Pointer to device node holding phandle property
1620 * @phandle_name: Name of property holding a phandle value
1621 * @index: For properties holding a table of phandles, this is the index into
1624 * Returns the device_node pointer with refcount incremented. Use
1625 * of_node_put() on it when done.
1627 struct device_node
*of_parse_phandle(const struct device_node
*np
,
1628 const char *phandle_name
, int index
)
1630 struct of_phandle_args args
;
1635 if (__of_parse_phandle_with_args(np
, phandle_name
, NULL
, 0,
1641 EXPORT_SYMBOL(of_parse_phandle
);
1644 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
1645 * @np: pointer to a device tree node containing a list
1646 * @list_name: property name that contains a list
1647 * @cells_name: property name that specifies phandles' arguments count
1648 * @index: index of a phandle to parse out
1649 * @out_args: optional pointer to output arguments structure (will be filled)
1651 * This function is useful to parse lists of phandles and their arguments.
1652 * Returns 0 on success and fills out_args, on error returns appropriate
1655 * Caller is responsible to call of_node_put() on the returned out_args->node
1661 * #list-cells = <2>;
1665 * #list-cells = <1>;
1669 * list = <&phandle1 1 2 &phandle2 3>;
1672 * To get a device_node of the `node2' node you may call this:
1673 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
1675 int of_parse_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1676 const char *cells_name
, int index
,
1677 struct of_phandle_args
*out_args
)
1681 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0,
1684 EXPORT_SYMBOL(of_parse_phandle_with_args
);
1687 * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
1688 * @np: pointer to a device tree node containing a list
1689 * @list_name: property name that contains a list
1690 * @cell_count: number of argument cells following the phandle
1691 * @index: index of a phandle to parse out
1692 * @out_args: optional pointer to output arguments structure (will be filled)
1694 * This function is useful to parse lists of phandles and their arguments.
1695 * Returns 0 on success and fills out_args, on error returns appropriate
1698 * Caller is responsible to call of_node_put() on the returned out_args->node
1710 * list = <&phandle1 0 2 &phandle2 2 3>;
1713 * To get a device_node of the `node2' node you may call this:
1714 * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
1716 int of_parse_phandle_with_fixed_args(const struct device_node
*np
,
1717 const char *list_name
, int cell_count
,
1718 int index
, struct of_phandle_args
*out_args
)
1722 return __of_parse_phandle_with_args(np
, list_name
, NULL
, cell_count
,
1725 EXPORT_SYMBOL(of_parse_phandle_with_fixed_args
);
1728 * of_count_phandle_with_args() - Find the number of phandles references in a property
1729 * @np: pointer to a device tree node containing a list
1730 * @list_name: property name that contains a list
1731 * @cells_name: property name that specifies phandles' arguments count
1733 * Returns the number of phandle + argument tuples within a property. It
1734 * is a typical pattern to encode a list of phandle and variable
1735 * arguments into a single property. The number of arguments is encoded
1736 * by a property in the phandle-target node. For example, a gpios
1737 * property would contain a list of GPIO specifies consisting of a
1738 * phandle and 1 or more arguments. The number of arguments are
1739 * determined by the #gpio-cells property in the node pointed to by the
1742 int of_count_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1743 const char *cells_name
)
1745 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0, -1,
1748 EXPORT_SYMBOL(of_count_phandle_with_args
);
1750 #if defined(CONFIG_OF_DYNAMIC)
1751 static int of_property_notify(int action
, struct device_node
*np
,
1752 struct property
*prop
)
1754 struct of_prop_reconfig pr
;
1756 /* only call notifiers if the node is attached */
1757 if (!of_node_is_attached(np
))
1762 return of_reconfig_notify(action
, &pr
);
1765 static int of_property_notify(int action
, struct device_node
*np
,
1766 struct property
*prop
)
1773 * __of_add_property - Add a property to a node without lock operations
1775 static int __of_add_property(struct device_node
*np
, struct property
*prop
)
1777 struct property
**next
;
1780 next
= &np
->properties
;
1782 if (strcmp(prop
->name
, (*next
)->name
) == 0)
1783 /* duplicate ! don't insert it */
1786 next
= &(*next
)->next
;
1794 * of_add_property - Add a property to a node
1796 int of_add_property(struct device_node
*np
, struct property
*prop
)
1798 unsigned long flags
;
1801 rc
= of_property_notify(OF_RECONFIG_ADD_PROPERTY
, np
, prop
);
1805 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1806 rc
= __of_add_property(np
, prop
);
1807 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1811 if (of_node_is_attached(np
))
1812 __of_add_property_sysfs(np
, prop
);
1818 * of_remove_property - Remove a property from a node.
1820 * Note that we don't actually remove it, since we have given out
1821 * who-knows-how-many pointers to the data using get-property.
1822 * Instead we just move the property to the "dead properties"
1823 * list, so it won't be found any more.
1825 int of_remove_property(struct device_node
*np
, struct property
*prop
)
1827 struct property
**next
;
1828 unsigned long flags
;
1832 rc
= of_property_notify(OF_RECONFIG_REMOVE_PROPERTY
, np
, prop
);
1836 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1837 next
= &np
->properties
;
1839 if (*next
== prop
) {
1840 /* found the node */
1842 prop
->next
= np
->deadprops
;
1843 np
->deadprops
= prop
;
1847 next
= &(*next
)->next
;
1849 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1854 /* at early boot, bail hear and defer setup to of_init() */
1858 sysfs_remove_bin_file(&np
->kobj
, &prop
->attr
);
1864 * of_update_property - Update a property in a node, if the property does
1865 * not exist, add it.
1867 * Note that we don't actually remove it, since we have given out
1868 * who-knows-how-many pointers to the data using get-property.
1869 * Instead we just move the property to the "dead properties" list,
1870 * and add the new property to the property list
1872 int of_update_property(struct device_node
*np
, struct property
*newprop
)
1874 struct property
**next
, *oldprop
;
1875 unsigned long flags
;
1878 rc
= of_property_notify(OF_RECONFIG_UPDATE_PROPERTY
, np
, newprop
);
1885 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1886 next
= &np
->properties
;
1887 oldprop
= __of_find_property(np
, newprop
->name
, NULL
);
1889 /* add the new node */
1890 rc
= __of_add_property(np
, newprop
);
1891 } else while (*next
) {
1892 /* replace the node */
1893 if (*next
== oldprop
) {
1894 newprop
->next
= oldprop
->next
;
1896 oldprop
->next
= np
->deadprops
;
1897 np
->deadprops
= oldprop
;
1900 next
= &(*next
)->next
;
1902 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1906 /* At early boot, bail out and defer setup to of_init() */
1910 /* Update the sysfs attribute */
1912 sysfs_remove_bin_file(&np
->kobj
, &oldprop
->attr
);
1913 __of_add_property_sysfs(np
, newprop
);
1918 #if defined(CONFIG_OF_DYNAMIC)
1920 * Support for dynamic device trees.
1922 * On some platforms, the device tree can be manipulated at runtime.
1923 * The routines in this section support adding, removing and changing
1924 * device tree nodes.
1927 static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain
);
1929 int of_reconfig_notifier_register(struct notifier_block
*nb
)
1931 return blocking_notifier_chain_register(&of_reconfig_chain
, nb
);
1933 EXPORT_SYMBOL_GPL(of_reconfig_notifier_register
);
1935 int of_reconfig_notifier_unregister(struct notifier_block
*nb
)
1937 return blocking_notifier_chain_unregister(&of_reconfig_chain
, nb
);
1939 EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister
);
1941 int of_reconfig_notify(unsigned long action
, void *p
)
1945 rc
= blocking_notifier_call_chain(&of_reconfig_chain
, action
, p
);
1946 return notifier_to_errno(rc
);
1950 * of_attach_node - Plug a device node into the tree and global list.
1952 int of_attach_node(struct device_node
*np
)
1954 unsigned long flags
;
1957 rc
= of_reconfig_notify(OF_RECONFIG_ATTACH_NODE
, np
);
1961 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1962 np
->sibling
= np
->parent
->child
;
1963 np
->allnext
= np
->parent
->allnext
;
1964 np
->parent
->allnext
= np
;
1965 np
->parent
->child
= np
;
1966 of_node_clear_flag(np
, OF_DETACHED
);
1967 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1974 * of_detach_node - "Unplug" a node from the device tree.
1976 * The caller must hold a reference to the node. The memory associated with
1977 * the node is not freed until its refcount goes to zero.
1979 int of_detach_node(struct device_node
*np
)
1981 struct device_node
*parent
;
1982 unsigned long flags
;
1985 rc
= of_reconfig_notify(OF_RECONFIG_DETACH_NODE
, np
);
1989 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1991 if (of_node_check_flag(np
, OF_DETACHED
)) {
1992 /* someone already detached it */
1993 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1997 parent
= np
->parent
;
1999 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
2003 if (of_allnodes
== np
)
2004 of_allnodes
= np
->allnext
;
2006 struct device_node
*prev
;
2007 for (prev
= of_allnodes
;
2008 prev
->allnext
!= np
;
2009 prev
= prev
->allnext
)
2011 prev
->allnext
= np
->allnext
;
2014 if (parent
->child
== np
)
2015 parent
->child
= np
->sibling
;
2017 struct device_node
*prevsib
;
2018 for (prevsib
= np
->parent
->child
;
2019 prevsib
->sibling
!= np
;
2020 prevsib
= prevsib
->sibling
)
2022 prevsib
->sibling
= np
->sibling
;
2025 of_node_set_flag(np
, OF_DETACHED
);
2026 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
2031 #endif /* defined(CONFIG_OF_DYNAMIC) */
2033 static void of_alias_add(struct alias_prop
*ap
, struct device_node
*np
,
2034 int id
, const char *stem
, int stem_len
)
2038 strncpy(ap
->stem
, stem
, stem_len
);
2039 ap
->stem
[stem_len
] = 0;
2040 list_add_tail(&ap
->link
, &aliases_lookup
);
2041 pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
2042 ap
->alias
, ap
->stem
, ap
->id
, of_node_full_name(np
));
2046 * of_alias_scan - Scan all properties of 'aliases' node
2048 * The function scans all the properties of 'aliases' node and populate
2049 * the the global lookup table with the properties. It returns the
2050 * number of alias_prop found, or error code in error case.
2052 * @dt_alloc: An allocator that provides a virtual address to memory
2053 * for the resulting tree
2055 void of_alias_scan(void * (*dt_alloc
)(u64 size
, u64 align
))
2057 struct property
*pp
;
2059 of_chosen
= of_find_node_by_path("/chosen");
2060 if (of_chosen
== NULL
)
2061 of_chosen
= of_find_node_by_path("/chosen@0");
2064 const char *name
= of_get_property(of_chosen
, "stdout-path", NULL
);
2066 name
= of_get_property(of_chosen
, "linux,stdout-path", NULL
);
2068 of_stdout
= of_find_node_by_path(name
);
2071 of_aliases
= of_find_node_by_path("/aliases");
2075 for_each_property_of_node(of_aliases
, pp
) {
2076 const char *start
= pp
->name
;
2077 const char *end
= start
+ strlen(start
);
2078 struct device_node
*np
;
2079 struct alias_prop
*ap
;
2082 /* Skip those we do not want to proceed */
2083 if (!strcmp(pp
->name
, "name") ||
2084 !strcmp(pp
->name
, "phandle") ||
2085 !strcmp(pp
->name
, "linux,phandle"))
2088 np
= of_find_node_by_path(pp
->value
);
2092 /* walk the alias backwards to extract the id and work out
2093 * the 'stem' string */
2094 while (isdigit(*(end
-1)) && end
> start
)
2098 if (kstrtoint(end
, 10, &id
) < 0)
2101 /* Allocate an alias_prop with enough space for the stem */
2102 ap
= dt_alloc(sizeof(*ap
) + len
+ 1, 4);
2105 memset(ap
, 0, sizeof(*ap
) + len
+ 1);
2107 of_alias_add(ap
, np
, id
, start
, len
);
2112 * of_alias_get_id - Get alias id for the given device_node
2113 * @np: Pointer to the given device_node
2114 * @stem: Alias stem of the given device_node
2116 * The function travels the lookup table to get the alias id for the given
2117 * device_node and alias stem. It returns the alias id if found.
2119 int of_alias_get_id(struct device_node
*np
, const char *stem
)
2121 struct alias_prop
*app
;
2124 mutex_lock(&of_mutex
);
2125 list_for_each_entry(app
, &aliases_lookup
, link
) {
2126 if (strcmp(app
->stem
, stem
) != 0)
2129 if (np
== app
->np
) {
2134 mutex_unlock(&of_mutex
);
2138 EXPORT_SYMBOL_GPL(of_alias_get_id
);
2140 const __be32
*of_prop_next_u32(struct property
*prop
, const __be32
*cur
,
2143 const void *curv
= cur
;
2153 curv
+= sizeof(*cur
);
2154 if (curv
>= prop
->value
+ prop
->length
)
2158 *pu
= be32_to_cpup(curv
);
2161 EXPORT_SYMBOL_GPL(of_prop_next_u32
);
2163 const char *of_prop_next_string(struct property
*prop
, const char *cur
)
2165 const void *curv
= cur
;
2173 curv
+= strlen(cur
) + 1;
2174 if (curv
>= prop
->value
+ prop
->length
)
2179 EXPORT_SYMBOL_GPL(of_prop_next_string
);
2182 * of_device_is_stdout_path - check if a device node matches the
2183 * linux,stdout-path property
2185 * Check if this device node matches the linux,stdout-path property
2186 * in the chosen node. return true if yes, false otherwise.
2188 int of_device_is_stdout_path(struct device_node
*dn
)
2193 return of_stdout
== dn
;
2195 EXPORT_SYMBOL_GPL(of_device_is_stdout_path
);
2198 * of_find_next_cache_node - Find a node's subsidiary cache
2199 * @np: node of type "cpu" or "cache"
2201 * Returns a node pointer with refcount incremented, use
2202 * of_node_put() on it when done. Caller should hold a reference
2205 struct device_node
*of_find_next_cache_node(const struct device_node
*np
)
2207 struct device_node
*child
;
2208 const phandle
*handle
;
2210 handle
= of_get_property(np
, "l2-cache", NULL
);
2212 handle
= of_get_property(np
, "next-level-cache", NULL
);
2215 return of_find_node_by_phandle(be32_to_cpup(handle
));
2217 /* OF on pmac has nodes instead of properties named "l2-cache"
2218 * beneath CPU nodes.
2220 if (!strcmp(np
->type
, "cpu"))
2221 for_each_child_of_node(np
, child
)
2222 if (!strcmp(child
->type
, "cache"))
2229 * of_graph_parse_endpoint() - parse common endpoint node properties
2230 * @node: pointer to endpoint device_node
2231 * @endpoint: pointer to the OF endpoint data structure
2233 * The caller should hold a reference to @node.
2235 int of_graph_parse_endpoint(const struct device_node
*node
,
2236 struct of_endpoint
*endpoint
)
2238 struct device_node
*port_node
= of_get_parent(node
);
2240 WARN_ONCE(!port_node
, "%s(): endpoint %s has no parent node\n",
2241 __func__
, node
->full_name
);
2243 memset(endpoint
, 0, sizeof(*endpoint
));
2245 endpoint
->local_node
= node
;
2247 * It doesn't matter whether the two calls below succeed.
2248 * If they don't then the default value 0 is used.
2250 of_property_read_u32(port_node
, "reg", &endpoint
->port
);
2251 of_property_read_u32(node
, "reg", &endpoint
->id
);
2253 of_node_put(port_node
);
2257 EXPORT_SYMBOL(of_graph_parse_endpoint
);
2260 * of_graph_get_next_endpoint() - get next endpoint node
2261 * @parent: pointer to the parent device node
2262 * @prev: previous endpoint node, or NULL to get first
2264 * Return: An 'endpoint' node pointer with refcount incremented. Refcount
2265 * of the passed @prev node is not decremented, the caller have to use
2266 * of_node_put() on it when done.
2268 struct device_node
*of_graph_get_next_endpoint(const struct device_node
*parent
,
2269 struct device_node
*prev
)
2271 struct device_node
*endpoint
;
2272 struct device_node
*port
;
2278 * Start by locating the port node. If no previous endpoint is specified
2279 * search for the first port node, otherwise get the previous endpoint
2283 struct device_node
*node
;
2285 node
= of_get_child_by_name(parent
, "ports");
2289 port
= of_get_child_by_name(parent
, "port");
2293 pr_err("%s(): no port node found in %s\n",
2294 __func__
, parent
->full_name
);
2298 port
= of_get_parent(prev
);
2299 if (WARN_ONCE(!port
, "%s(): endpoint %s has no parent node\n",
2300 __func__
, prev
->full_name
))
2304 * Avoid dropping prev node refcount to 0 when getting the next
2312 * Now that we have a port node, get the next endpoint by
2313 * getting the next child. If the previous endpoint is NULL this
2314 * will return the first child.
2316 endpoint
= of_get_next_child(port
, prev
);
2322 /* No more endpoints under this port, try the next one. */
2326 port
= of_get_next_child(parent
, port
);
2329 } while (of_node_cmp(port
->name
, "port"));
2332 EXPORT_SYMBOL(of_graph_get_next_endpoint
);
2335 * of_graph_get_remote_port_parent() - get remote port's parent node
2336 * @node: pointer to a local endpoint device_node
2338 * Return: Remote device node associated with remote endpoint node linked
2339 * to @node. Use of_node_put() on it when done.
2341 struct device_node
*of_graph_get_remote_port_parent(
2342 const struct device_node
*node
)
2344 struct device_node
*np
;
2347 /* Get remote endpoint node. */
2348 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2350 /* Walk 3 levels up only if there is 'ports' node. */
2351 for (depth
= 3; depth
&& np
; depth
--) {
2352 np
= of_get_next_parent(np
);
2353 if (depth
== 2 && of_node_cmp(np
->name
, "ports"))
2358 EXPORT_SYMBOL(of_graph_get_remote_port_parent
);
2361 * of_graph_get_remote_port() - get remote port node
2362 * @node: pointer to a local endpoint device_node
2364 * Return: Remote port node associated with remote endpoint node linked
2365 * to @node. Use of_node_put() on it when done.
2367 struct device_node
*of_graph_get_remote_port(const struct device_node
*node
)
2369 struct device_node
*np
;
2371 /* Get remote endpoint node. */
2372 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2375 return of_get_next_parent(np
);
2377 EXPORT_SYMBOL(of_graph_get_remote_port
);