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; but also overloaded to hold off addition of
46 DEFINE_MUTEX(of_aliases_mutex
);
48 /* use when traversing tree through the allnext, child, sibling,
49 * or parent members of struct device_node.
51 DEFINE_RAW_SPINLOCK(devtree_lock
);
53 int of_n_addr_cells(struct device_node
*np
)
60 ip
= of_get_property(np
, "#address-cells", NULL
);
62 return be32_to_cpup(ip
);
64 /* No #address-cells property for the root node */
65 return OF_ROOT_NODE_ADDR_CELLS_DEFAULT
;
67 EXPORT_SYMBOL(of_n_addr_cells
);
69 int of_n_size_cells(struct device_node
*np
)
76 ip
= of_get_property(np
, "#size-cells", NULL
);
78 return be32_to_cpup(ip
);
80 /* No #size-cells property for the root node */
81 return OF_ROOT_NODE_SIZE_CELLS_DEFAULT
;
83 EXPORT_SYMBOL(of_n_size_cells
);
86 int __weak
of_node_to_nid(struct device_node
*np
)
88 return numa_node_id();
92 #if defined(CONFIG_OF_DYNAMIC)
94 * of_node_get - Increment refcount of a node
95 * @node: Node to inc refcount, NULL is supported to
96 * simplify writing of callers
100 struct device_node
*of_node_get(struct device_node
*node
)
103 kobject_get(&node
->kobj
);
106 EXPORT_SYMBOL(of_node_get
);
108 static inline struct device_node
*kobj_to_device_node(struct kobject
*kobj
)
110 return container_of(kobj
, struct device_node
, kobj
);
114 * of_node_release - release a dynamically allocated node
115 * @kref: kref element of the node to be released
117 * In of_node_put() this function is passed to kref_put()
120 static void of_node_release(struct kobject
*kobj
)
122 struct device_node
*node
= kobj_to_device_node(kobj
);
123 struct property
*prop
= node
->properties
;
125 /* We should never be releasing nodes that haven't been detached. */
126 if (!of_node_check_flag(node
, OF_DETACHED
)) {
127 pr_err("ERROR: Bad of_node_put() on %s\n", node
->full_name
);
132 if (!of_node_check_flag(node
, OF_DYNAMIC
))
136 struct property
*next
= prop
->next
;
143 prop
= node
->deadprops
;
144 node
->deadprops
= NULL
;
147 kfree(node
->full_name
);
153 * of_node_put - Decrement refcount of a node
154 * @node: Node to dec refcount, NULL is supported to
155 * simplify writing of callers
158 void of_node_put(struct device_node
*node
)
161 kobject_put(&node
->kobj
);
163 EXPORT_SYMBOL(of_node_put
);
165 static void of_node_release(struct kobject
*kobj
)
167 /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
169 #endif /* CONFIG_OF_DYNAMIC */
171 struct kobj_type of_node_ktype
= {
172 .release
= of_node_release
,
175 static ssize_t
of_node_property_read(struct file
*filp
, struct kobject
*kobj
,
176 struct bin_attribute
*bin_attr
, char *buf
,
177 loff_t offset
, size_t count
)
179 struct property
*pp
= container_of(bin_attr
, struct property
, attr
);
180 return memory_read_from_buffer(buf
, count
, &offset
, pp
->value
, pp
->length
);
183 static const char *safe_name(struct kobject
*kobj
, const char *orig_name
)
185 const char *name
= orig_name
;
186 struct kernfs_node
*kn
;
189 /* don't be a hero. After 16 tries give up */
190 while (i
< 16 && (kn
= sysfs_get_dirent(kobj
->sd
, name
))) {
192 if (name
!= orig_name
)
194 name
= kasprintf(GFP_KERNEL
, "%s#%i", orig_name
, ++i
);
197 if (name
!= orig_name
)
198 pr_warn("device-tree: Duplicate name in %s, renamed to \"%s\"\n",
199 kobject_name(kobj
), name
);
203 static int __of_add_property_sysfs(struct device_node
*np
, struct property
*pp
)
207 /* Important: Don't leak passwords */
208 bool secure
= strncmp(pp
->name
, "security-", 9) == 0;
210 sysfs_bin_attr_init(&pp
->attr
);
211 pp
->attr
.attr
.name
= safe_name(&np
->kobj
, pp
->name
);
212 pp
->attr
.attr
.mode
= secure
? S_IRUSR
: S_IRUGO
;
213 pp
->attr
.size
= secure
? 0 : pp
->length
;
214 pp
->attr
.read
= of_node_property_read
;
216 rc
= sysfs_create_bin_file(&np
->kobj
, &pp
->attr
);
217 WARN(rc
, "error adding attribute %s to node %s\n", pp
->name
, np
->full_name
);
221 static int __of_node_add(struct device_node
*np
)
227 np
->kobj
.kset
= of_kset
;
229 /* Nodes without parents are new top level trees */
230 rc
= kobject_add(&np
->kobj
, NULL
, 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_aliases_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_aliases_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_aliases_mutex
);
292 of_kset
= kset_create_and_add("devicetree", NULL
, firmware_kobj
);
294 mutex_unlock(&of_aliases_mutex
);
297 for_each_of_allnodes(np
)
299 mutex_unlock(&of_aliases_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
);
699 * of_get_next_child - Iterate a node childs
701 * @prev: previous child of the parent node, or NULL to get first
703 * Returns a node pointer with refcount incremented, use
704 * of_node_put() on it when done.
706 struct device_node
*of_get_next_child(const struct device_node
*node
,
707 struct device_node
*prev
)
709 struct device_node
*next
;
712 raw_spin_lock_irqsave(&devtree_lock
, flags
);
713 next
= prev
? prev
->sibling
: node
->child
;
714 for (; next
; next
= next
->sibling
)
715 if (of_node_get(next
))
718 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
721 EXPORT_SYMBOL(of_get_next_child
);
724 * of_get_next_available_child - Find the next available child node
726 * @prev: previous child of the parent node, or NULL to get first
728 * This function is like of_get_next_child(), except that it
729 * automatically skips any disabled nodes (i.e. status = "disabled").
731 struct device_node
*of_get_next_available_child(const struct device_node
*node
,
732 struct device_node
*prev
)
734 struct device_node
*next
;
737 raw_spin_lock_irqsave(&devtree_lock
, flags
);
738 next
= prev
? prev
->sibling
: node
->child
;
739 for (; next
; next
= next
->sibling
) {
740 if (!__of_device_is_available(next
))
742 if (of_node_get(next
))
746 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
749 EXPORT_SYMBOL(of_get_next_available_child
);
752 * of_get_child_by_name - Find the child node by name for a given parent
754 * @name: child name to look for.
756 * This function looks for child node for given matching name
758 * Returns a node pointer if found, with refcount incremented, use
759 * of_node_put() on it when done.
760 * Returns NULL if node is not found.
762 struct device_node
*of_get_child_by_name(const struct device_node
*node
,
765 struct device_node
*child
;
767 for_each_child_of_node(node
, child
)
768 if (child
->name
&& (of_node_cmp(child
->name
, name
) == 0))
772 EXPORT_SYMBOL(of_get_child_by_name
);
775 * of_find_node_by_path - Find a node matching a full OF path
776 * @path: The full path to match
778 * Returns a node pointer with refcount incremented, use
779 * of_node_put() on it when done.
781 struct device_node
*of_find_node_by_path(const char *path
)
783 struct device_node
*np
= of_allnodes
;
786 raw_spin_lock_irqsave(&devtree_lock
, flags
);
787 for (; np
; np
= np
->allnext
) {
788 if (np
->full_name
&& (of_node_cmp(np
->full_name
, path
) == 0)
792 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
795 EXPORT_SYMBOL(of_find_node_by_path
);
798 * of_find_node_by_name - Find a node by its "name" property
799 * @from: The node to start searching from or NULL, the node
800 * you pass will not be searched, only the next one
801 * will; typically, you pass what the previous call
802 * returned. of_node_put() will be called on it
803 * @name: The name string to match against
805 * Returns a node pointer with refcount incremented, use
806 * of_node_put() on it when done.
808 struct device_node
*of_find_node_by_name(struct device_node
*from
,
811 struct device_node
*np
;
814 raw_spin_lock_irqsave(&devtree_lock
, flags
);
815 np
= from
? from
->allnext
: of_allnodes
;
816 for (; np
; np
= np
->allnext
)
817 if (np
->name
&& (of_node_cmp(np
->name
, name
) == 0)
821 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
824 EXPORT_SYMBOL(of_find_node_by_name
);
827 * of_find_node_by_type - Find a node by its "device_type" property
828 * @from: The node to start searching from, or NULL to start searching
829 * the entire device tree. The node you pass will not be
830 * searched, only the next one will; typically, you pass
831 * what the previous call returned. of_node_put() will be
832 * called on from for you.
833 * @type: The type string to match against
835 * Returns a node pointer with refcount incremented, use
836 * of_node_put() on it when done.
838 struct device_node
*of_find_node_by_type(struct device_node
*from
,
841 struct device_node
*np
;
844 raw_spin_lock_irqsave(&devtree_lock
, flags
);
845 np
= from
? from
->allnext
: of_allnodes
;
846 for (; np
; np
= np
->allnext
)
847 if (np
->type
&& (of_node_cmp(np
->type
, type
) == 0)
851 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
854 EXPORT_SYMBOL(of_find_node_by_type
);
857 * of_find_compatible_node - Find a node based on type and one of the
858 * tokens in its "compatible" property
859 * @from: The node to start searching from or NULL, the node
860 * you pass will not be searched, only the next one
861 * will; typically, you pass what the previous call
862 * returned. of_node_put() will be called on it
863 * @type: The type string to match "device_type" or NULL to ignore
864 * @compatible: The string to match to one of the tokens in the device
867 * Returns a node pointer with refcount incremented, use
868 * of_node_put() on it when done.
870 struct device_node
*of_find_compatible_node(struct device_node
*from
,
871 const char *type
, const char *compatible
)
873 struct device_node
*np
;
876 raw_spin_lock_irqsave(&devtree_lock
, flags
);
877 np
= from
? from
->allnext
: of_allnodes
;
878 for (; np
; np
= np
->allnext
) {
879 if (__of_device_is_compatible(np
, compatible
, type
, NULL
) &&
884 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
887 EXPORT_SYMBOL(of_find_compatible_node
);
890 * of_find_node_with_property - Find a node which has a property with
892 * @from: The node to start searching from or NULL, the node
893 * you pass will not be searched, only the next one
894 * will; typically, you pass what the previous call
895 * returned. of_node_put() will be called on it
896 * @prop_name: The name of the property to look for.
898 * Returns a node pointer with refcount incremented, use
899 * of_node_put() on it when done.
901 struct device_node
*of_find_node_with_property(struct device_node
*from
,
902 const char *prop_name
)
904 struct device_node
*np
;
908 raw_spin_lock_irqsave(&devtree_lock
, flags
);
909 np
= from
? from
->allnext
: of_allnodes
;
910 for (; np
; np
= np
->allnext
) {
911 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
912 if (of_prop_cmp(pp
->name
, prop_name
) == 0) {
920 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
923 EXPORT_SYMBOL(of_find_node_with_property
);
926 const struct of_device_id
*__of_match_node(const struct of_device_id
*matches
,
927 const struct device_node
*node
)
929 const struct of_device_id
*best_match
= NULL
;
930 int score
, best_score
= 0;
935 for (; matches
->name
[0] || matches
->type
[0] || matches
->compatible
[0]; matches
++) {
936 score
= __of_device_is_compatible(node
, matches
->compatible
,
937 matches
->type
, matches
->name
);
938 if (score
> best_score
) {
939 best_match
= matches
;
948 * of_match_node - Tell if an device_node has a matching of_match structure
949 * @matches: array of of device match structures to search in
950 * @node: the of device structure to match against
952 * Low level utility function used by device matching.
954 const struct of_device_id
*of_match_node(const struct of_device_id
*matches
,
955 const struct device_node
*node
)
957 const struct of_device_id
*match
;
960 raw_spin_lock_irqsave(&devtree_lock
, flags
);
961 match
= __of_match_node(matches
, node
);
962 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
965 EXPORT_SYMBOL(of_match_node
);
968 * of_find_matching_node_and_match - Find a node based on an of_device_id
970 * @from: The node to start searching from or NULL, the node
971 * you pass will not be searched, only the next one
972 * will; typically, you pass what the previous call
973 * returned. of_node_put() will be called on it
974 * @matches: array of of device match structures to search in
975 * @match Updated to point at the matches entry which matched
977 * Returns a node pointer with refcount incremented, use
978 * of_node_put() on it when done.
980 struct device_node
*of_find_matching_node_and_match(struct device_node
*from
,
981 const struct of_device_id
*matches
,
982 const struct of_device_id
**match
)
984 struct device_node
*np
;
985 const struct of_device_id
*m
;
991 raw_spin_lock_irqsave(&devtree_lock
, flags
);
992 np
= from
? from
->allnext
: of_allnodes
;
993 for (; np
; np
= np
->allnext
) {
994 m
= __of_match_node(matches
, np
);
995 if (m
&& of_node_get(np
)) {
1002 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1005 EXPORT_SYMBOL(of_find_matching_node_and_match
);
1008 * of_modalias_node - Lookup appropriate modalias for a device node
1009 * @node: pointer to a device tree node
1010 * @modalias: Pointer to buffer that modalias value will be copied into
1011 * @len: Length of modalias value
1013 * Based on the value of the compatible property, this routine will attempt
1014 * to choose an appropriate modalias value for a particular device tree node.
1015 * It does this by stripping the manufacturer prefix (as delimited by a ',')
1016 * from the first entry in the compatible list property.
1018 * This routine returns 0 on success, <0 on failure.
1020 int of_modalias_node(struct device_node
*node
, char *modalias
, int len
)
1022 const char *compatible
, *p
;
1025 compatible
= of_get_property(node
, "compatible", &cplen
);
1026 if (!compatible
|| strlen(compatible
) > cplen
)
1028 p
= strchr(compatible
, ',');
1029 strlcpy(modalias
, p
? p
+ 1 : compatible
, len
);
1032 EXPORT_SYMBOL_GPL(of_modalias_node
);
1035 * of_find_node_by_phandle - Find a node given a phandle
1036 * @handle: phandle of the node to find
1038 * Returns a node pointer with refcount incremented, use
1039 * of_node_put() on it when done.
1041 struct device_node
*of_find_node_by_phandle(phandle handle
)
1043 struct device_node
*np
;
1044 unsigned long flags
;
1046 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1047 for (np
= of_allnodes
; np
; np
= np
->allnext
)
1048 if (np
->phandle
== handle
)
1051 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1054 EXPORT_SYMBOL(of_find_node_by_phandle
);
1057 * of_property_count_elems_of_size - Count the number of elements in a property
1059 * @np: device node from which the property value is to be read.
1060 * @propname: name of the property to be searched.
1061 * @elem_size: size of the individual element
1063 * Search for a property in a device node and count the number of elements of
1064 * size elem_size in it. Returns number of elements on sucess, -EINVAL if the
1065 * property does not exist or its length does not match a multiple of elem_size
1066 * and -ENODATA if the property does not have a value.
1068 int of_property_count_elems_of_size(const struct device_node
*np
,
1069 const char *propname
, int elem_size
)
1071 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1078 if (prop
->length
% elem_size
!= 0) {
1079 pr_err("size of %s in node %s is not a multiple of %d\n",
1080 propname
, np
->full_name
, elem_size
);
1084 return prop
->length
/ elem_size
;
1086 EXPORT_SYMBOL_GPL(of_property_count_elems_of_size
);
1089 * of_find_property_value_of_size
1091 * @np: device node from which the property value is to be read.
1092 * @propname: name of the property to be searched.
1093 * @len: requested length of property value
1095 * Search for a property in a device node and valid the requested size.
1096 * Returns the property value on success, -EINVAL if the property does not
1097 * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
1098 * property data isn't large enough.
1101 static void *of_find_property_value_of_size(const struct device_node
*np
,
1102 const char *propname
, u32 len
)
1104 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1107 return ERR_PTR(-EINVAL
);
1109 return ERR_PTR(-ENODATA
);
1110 if (len
> prop
->length
)
1111 return ERR_PTR(-EOVERFLOW
);
1117 * of_property_read_u32_index - Find and read a u32 from a multi-value property.
1119 * @np: device node from which the property value is to be read.
1120 * @propname: name of the property to be searched.
1121 * @index: index of the u32 in the list of values
1122 * @out_value: pointer to return value, modified only if no error.
1124 * Search for a property in a device node and read nth 32-bit value from
1125 * it. Returns 0 on success, -EINVAL if the property does not exist,
1126 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1127 * property data isn't large enough.
1129 * The out_value is modified only if a valid u32 value can be decoded.
1131 int of_property_read_u32_index(const struct device_node
*np
,
1132 const char *propname
,
1133 u32 index
, u32
*out_value
)
1135 const u32
*val
= of_find_property_value_of_size(np
, propname
,
1136 ((index
+ 1) * sizeof(*out_value
)));
1139 return PTR_ERR(val
);
1141 *out_value
= be32_to_cpup(((__be32
*)val
) + index
);
1144 EXPORT_SYMBOL_GPL(of_property_read_u32_index
);
1147 * of_property_read_u8_array - Find and read an array of u8 from a property.
1149 * @np: device node from which the property value is to be read.
1150 * @propname: name of the property to be searched.
1151 * @out_values: pointer to return value, modified only if return value is 0.
1152 * @sz: number of array elements to read
1154 * Search for a property in a device node and read 8-bit value(s) from
1155 * it. Returns 0 on success, -EINVAL if the property does not exist,
1156 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1157 * property data isn't large enough.
1159 * dts entry of array should be like:
1160 * property = /bits/ 8 <0x50 0x60 0x70>;
1162 * The out_values is modified only if a valid u8 value can be decoded.
1164 int of_property_read_u8_array(const struct device_node
*np
,
1165 const char *propname
, u8
*out_values
, size_t sz
)
1167 const u8
*val
= of_find_property_value_of_size(np
, propname
,
1168 (sz
* sizeof(*out_values
)));
1171 return PTR_ERR(val
);
1174 *out_values
++ = *val
++;
1177 EXPORT_SYMBOL_GPL(of_property_read_u8_array
);
1180 * of_property_read_u16_array - Find and read an array of u16 from a property.
1182 * @np: device node from which the property value is to be read.
1183 * @propname: name of the property to be searched.
1184 * @out_values: pointer to return value, modified only if return value is 0.
1185 * @sz: number of array elements to read
1187 * Search for a property in a device node and read 16-bit value(s) from
1188 * it. Returns 0 on success, -EINVAL if the property does not exist,
1189 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1190 * property data isn't large enough.
1192 * dts entry of array should be like:
1193 * property = /bits/ 16 <0x5000 0x6000 0x7000>;
1195 * The out_values is modified only if a valid u16 value can be decoded.
1197 int of_property_read_u16_array(const struct device_node
*np
,
1198 const char *propname
, u16
*out_values
, size_t sz
)
1200 const __be16
*val
= of_find_property_value_of_size(np
, propname
,
1201 (sz
* sizeof(*out_values
)));
1204 return PTR_ERR(val
);
1207 *out_values
++ = be16_to_cpup(val
++);
1210 EXPORT_SYMBOL_GPL(of_property_read_u16_array
);
1213 * of_property_read_u32_array - Find and read an array of 32 bit integers
1216 * @np: device node from which the property value is to be read.
1217 * @propname: name of the property to be searched.
1218 * @out_values: pointer to return value, modified only if return value is 0.
1219 * @sz: number of array elements to read
1221 * Search for a property in a device node and read 32-bit value(s) from
1222 * it. Returns 0 on success, -EINVAL if the property does not exist,
1223 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1224 * property data isn't large enough.
1226 * The out_values is modified only if a valid u32 value can be decoded.
1228 int of_property_read_u32_array(const struct device_node
*np
,
1229 const char *propname
, u32
*out_values
,
1232 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1233 (sz
* sizeof(*out_values
)));
1236 return PTR_ERR(val
);
1239 *out_values
++ = be32_to_cpup(val
++);
1242 EXPORT_SYMBOL_GPL(of_property_read_u32_array
);
1245 * of_property_read_u64 - Find and read a 64 bit integer from a property
1246 * @np: device node from which the property value is to be read.
1247 * @propname: name of the property to be searched.
1248 * @out_value: pointer to return value, modified only if return value is 0.
1250 * Search for a property in a device node and read a 64-bit value from
1251 * it. Returns 0 on success, -EINVAL if the property does not exist,
1252 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1253 * property data isn't large enough.
1255 * The out_value is modified only if a valid u64 value can be decoded.
1257 int of_property_read_u64(const struct device_node
*np
, const char *propname
,
1260 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1261 sizeof(*out_value
));
1264 return PTR_ERR(val
);
1266 *out_value
= of_read_number(val
, 2);
1269 EXPORT_SYMBOL_GPL(of_property_read_u64
);
1272 * of_property_read_string - Find and read a string from a property
1273 * @np: device node from which the property value is to be read.
1274 * @propname: name of the property to be searched.
1275 * @out_string: pointer to null terminated return string, modified only if
1276 * return value is 0.
1278 * Search for a property in a device tree node and retrieve a null
1279 * terminated string value (pointer to data, not a copy). Returns 0 on
1280 * success, -EINVAL if the property does not exist, -ENODATA if property
1281 * does not have a value, and -EILSEQ if the string is not null-terminated
1282 * within the length of the property data.
1284 * The out_string pointer is modified only if a valid string can be decoded.
1286 int of_property_read_string(struct device_node
*np
, const char *propname
,
1287 const char **out_string
)
1289 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1294 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1296 *out_string
= prop
->value
;
1299 EXPORT_SYMBOL_GPL(of_property_read_string
);
1302 * of_property_read_string_index - Find and read a string from a multiple
1304 * @np: device node from which the property value is to be read.
1305 * @propname: name of the property to be searched.
1306 * @index: index of the string in the list of strings
1307 * @out_string: pointer to null terminated return string, modified only if
1308 * return value is 0.
1310 * Search for a property in a device tree node and retrieve a null
1311 * terminated string value (pointer to data, not a copy) in the list of strings
1312 * contained in that property.
1313 * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
1314 * property does not have a value, and -EILSEQ if the string is not
1315 * null-terminated within the length of the property data.
1317 * The out_string pointer is modified only if a valid string can be decoded.
1319 int of_property_read_string_index(struct device_node
*np
, const char *propname
,
1320 int index
, const char **output
)
1322 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1324 size_t l
= 0, total
= 0;
1331 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1336 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
) {
1345 EXPORT_SYMBOL_GPL(of_property_read_string_index
);
1348 * of_property_match_string() - Find string in a list and return index
1349 * @np: pointer to node containing string list property
1350 * @propname: string list property name
1351 * @string: pointer to string to search for in string list
1353 * This function searches a string list property and returns the index
1354 * of a specific string value.
1356 int of_property_match_string(struct device_node
*np
, const char *propname
,
1359 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1362 const char *p
, *end
;
1370 end
= p
+ prop
->length
;
1372 for (i
= 0; p
< end
; i
++, p
+= l
) {
1376 pr_debug("comparing %s with %s\n", string
, p
);
1377 if (strcmp(string
, p
) == 0)
1378 return i
; /* Found it; return index */
1382 EXPORT_SYMBOL_GPL(of_property_match_string
);
1385 * of_property_count_strings - Find and return the number of strings from a
1386 * multiple strings property.
1387 * @np: device node from which the property value is to be read.
1388 * @propname: name of the property to be searched.
1390 * Search for a property in a device tree node and retrieve the number of null
1391 * terminated string contain in it. Returns the number of strings on
1392 * success, -EINVAL if the property does not exist, -ENODATA if property
1393 * does not have a value, and -EILSEQ if the string is not null-terminated
1394 * within the length of the property data.
1396 int of_property_count_strings(struct device_node
*np
, const char *propname
)
1398 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1400 size_t l
= 0, total
= 0;
1407 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1412 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
, i
++)
1417 EXPORT_SYMBOL_GPL(of_property_count_strings
);
1419 void of_print_phandle_args(const char *msg
, const struct of_phandle_args
*args
)
1422 printk("%s %s", msg
, of_node_full_name(args
->np
));
1423 for (i
= 0; i
< args
->args_count
; i
++)
1424 printk(i
? ",%08x" : ":%08x", args
->args
[i
]);
1428 static int __of_parse_phandle_with_args(const struct device_node
*np
,
1429 const char *list_name
,
1430 const char *cells_name
,
1431 int cell_count
, int index
,
1432 struct of_phandle_args
*out_args
)
1434 const __be32
*list
, *list_end
;
1435 int rc
= 0, size
, cur_index
= 0;
1437 struct device_node
*node
= NULL
;
1440 /* Retrieve the phandle list property */
1441 list
= of_get_property(np
, list_name
, &size
);
1444 list_end
= list
+ size
/ sizeof(*list
);
1446 /* Loop over the phandles until all the requested entry is found */
1447 while (list
< list_end
) {
1452 * If phandle is 0, then it is an empty entry with no
1453 * arguments. Skip forward to the next entry.
1455 phandle
= be32_to_cpup(list
++);
1458 * Find the provider node and parse the #*-cells
1459 * property to determine the argument length.
1461 * This is not needed if the cell count is hard-coded
1462 * (i.e. cells_name not set, but cell_count is set),
1463 * except when we're going to return the found node
1466 if (cells_name
|| cur_index
== index
) {
1467 node
= of_find_node_by_phandle(phandle
);
1469 pr_err("%s: could not find phandle\n",
1476 if (of_property_read_u32(node
, cells_name
,
1478 pr_err("%s: could not get %s for %s\n",
1479 np
->full_name
, cells_name
,
1488 * Make sure that the arguments actually fit in the
1489 * remaining property data length
1491 if (list
+ count
> list_end
) {
1492 pr_err("%s: arguments longer than property\n",
1499 * All of the error cases above bail out of the loop, so at
1500 * this point, the parsing is successful. If the requested
1501 * index matches, then fill the out_args structure and return,
1502 * or return -ENOENT for an empty entry.
1505 if (cur_index
== index
) {
1511 if (WARN_ON(count
> MAX_PHANDLE_ARGS
))
1512 count
= MAX_PHANDLE_ARGS
;
1513 out_args
->np
= node
;
1514 out_args
->args_count
= count
;
1515 for (i
= 0; i
< count
; i
++)
1516 out_args
->args
[i
] = be32_to_cpup(list
++);
1521 /* Found it! return success */
1532 * Unlock node before returning result; will be one of:
1533 * -ENOENT : index is for empty phandle
1534 * -EINVAL : parsing error on data
1535 * [1..n] : Number of phandle (count mode; when index = -1)
1537 rc
= index
< 0 ? cur_index
: -ENOENT
;
1545 * of_parse_phandle - Resolve a phandle property to a device_node pointer
1546 * @np: Pointer to device node holding phandle property
1547 * @phandle_name: Name of property holding a phandle value
1548 * @index: For properties holding a table of phandles, this is the index into
1551 * Returns the device_node pointer with refcount incremented. Use
1552 * of_node_put() on it when done.
1554 struct device_node
*of_parse_phandle(const struct device_node
*np
,
1555 const char *phandle_name
, int index
)
1557 struct of_phandle_args args
;
1562 if (__of_parse_phandle_with_args(np
, phandle_name
, NULL
, 0,
1568 EXPORT_SYMBOL(of_parse_phandle
);
1571 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
1572 * @np: pointer to a device tree node containing a list
1573 * @list_name: property name that contains a list
1574 * @cells_name: property name that specifies phandles' arguments count
1575 * @index: index of a phandle to parse out
1576 * @out_args: optional pointer to output arguments structure (will be filled)
1578 * This function is useful to parse lists of phandles and their arguments.
1579 * Returns 0 on success and fills out_args, on error returns appropriate
1582 * Caller is responsible to call of_node_put() on the returned out_args->node
1588 * #list-cells = <2>;
1592 * #list-cells = <1>;
1596 * list = <&phandle1 1 2 &phandle2 3>;
1599 * To get a device_node of the `node2' node you may call this:
1600 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
1602 int of_parse_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1603 const char *cells_name
, int index
,
1604 struct of_phandle_args
*out_args
)
1608 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0,
1611 EXPORT_SYMBOL(of_parse_phandle_with_args
);
1614 * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
1615 * @np: pointer to a device tree node containing a list
1616 * @list_name: property name that contains a list
1617 * @cell_count: number of argument cells following the phandle
1618 * @index: index of a phandle to parse out
1619 * @out_args: optional pointer to output arguments structure (will be filled)
1621 * This function is useful to parse lists of phandles and their arguments.
1622 * Returns 0 on success and fills out_args, on error returns appropriate
1625 * Caller is responsible to call of_node_put() on the returned out_args->node
1637 * list = <&phandle1 0 2 &phandle2 2 3>;
1640 * To get a device_node of the `node2' node you may call this:
1641 * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
1643 int of_parse_phandle_with_fixed_args(const struct device_node
*np
,
1644 const char *list_name
, int cell_count
,
1645 int index
, struct of_phandle_args
*out_args
)
1649 return __of_parse_phandle_with_args(np
, list_name
, NULL
, cell_count
,
1652 EXPORT_SYMBOL(of_parse_phandle_with_fixed_args
);
1655 * of_count_phandle_with_args() - Find the number of phandles references in a property
1656 * @np: pointer to a device tree node containing a list
1657 * @list_name: property name that contains a list
1658 * @cells_name: property name that specifies phandles' arguments count
1660 * Returns the number of phandle + argument tuples within a property. It
1661 * is a typical pattern to encode a list of phandle and variable
1662 * arguments into a single property. The number of arguments is encoded
1663 * by a property in the phandle-target node. For example, a gpios
1664 * property would contain a list of GPIO specifies consisting of a
1665 * phandle and 1 or more arguments. The number of arguments are
1666 * determined by the #gpio-cells property in the node pointed to by the
1669 int of_count_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1670 const char *cells_name
)
1672 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0, -1,
1675 EXPORT_SYMBOL(of_count_phandle_with_args
);
1677 #if defined(CONFIG_OF_DYNAMIC)
1678 static int of_property_notify(int action
, struct device_node
*np
,
1679 struct property
*prop
)
1681 struct of_prop_reconfig pr
;
1683 /* only call notifiers if the node is attached */
1684 if (!of_node_is_attached(np
))
1689 return of_reconfig_notify(action
, &pr
);
1692 static int of_property_notify(int action
, struct device_node
*np
,
1693 struct property
*prop
)
1700 * __of_add_property - Add a property to a node without lock operations
1702 static int __of_add_property(struct device_node
*np
, struct property
*prop
)
1704 struct property
**next
;
1707 next
= &np
->properties
;
1709 if (strcmp(prop
->name
, (*next
)->name
) == 0)
1710 /* duplicate ! don't insert it */
1713 next
= &(*next
)->next
;
1721 * of_add_property - Add a property to a node
1723 int of_add_property(struct device_node
*np
, struct property
*prop
)
1725 unsigned long flags
;
1728 rc
= of_property_notify(OF_RECONFIG_ADD_PROPERTY
, np
, prop
);
1732 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1733 rc
= __of_add_property(np
, prop
);
1734 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1738 if (of_node_is_attached(np
))
1739 __of_add_property_sysfs(np
, prop
);
1745 * of_remove_property - Remove a property from a node.
1747 * Note that we don't actually remove it, since we have given out
1748 * who-knows-how-many pointers to the data using get-property.
1749 * Instead we just move the property to the "dead properties"
1750 * list, so it won't be found any more.
1752 int of_remove_property(struct device_node
*np
, struct property
*prop
)
1754 struct property
**next
;
1755 unsigned long flags
;
1759 rc
= of_property_notify(OF_RECONFIG_REMOVE_PROPERTY
, np
, prop
);
1763 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1764 next
= &np
->properties
;
1766 if (*next
== prop
) {
1767 /* found the node */
1769 prop
->next
= np
->deadprops
;
1770 np
->deadprops
= prop
;
1774 next
= &(*next
)->next
;
1776 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1781 /* at early boot, bail hear and defer setup to of_init() */
1785 sysfs_remove_bin_file(&np
->kobj
, &prop
->attr
);
1791 * of_update_property - Update a property in a node, if the property does
1792 * not exist, add it.
1794 * Note that we don't actually remove it, since we have given out
1795 * who-knows-how-many pointers to the data using get-property.
1796 * Instead we just move the property to the "dead properties" list,
1797 * and add the new property to the property list
1799 int of_update_property(struct device_node
*np
, struct property
*newprop
)
1801 struct property
**next
, *oldprop
;
1802 unsigned long flags
;
1805 rc
= of_property_notify(OF_RECONFIG_UPDATE_PROPERTY
, np
, newprop
);
1812 oldprop
= of_find_property(np
, newprop
->name
, NULL
);
1814 return of_add_property(np
, newprop
);
1816 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1817 next
= &np
->properties
;
1819 if (*next
== oldprop
) {
1820 /* found the node */
1821 newprop
->next
= oldprop
->next
;
1823 oldprop
->next
= np
->deadprops
;
1824 np
->deadprops
= oldprop
;
1828 next
= &(*next
)->next
;
1830 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1834 /* Update the sysfs attribute */
1835 sysfs_remove_bin_file(&np
->kobj
, &oldprop
->attr
);
1836 __of_add_property_sysfs(np
, newprop
);
1841 #if defined(CONFIG_OF_DYNAMIC)
1843 * Support for dynamic device trees.
1845 * On some platforms, the device tree can be manipulated at runtime.
1846 * The routines in this section support adding, removing and changing
1847 * device tree nodes.
1850 static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain
);
1852 int of_reconfig_notifier_register(struct notifier_block
*nb
)
1854 return blocking_notifier_chain_register(&of_reconfig_chain
, nb
);
1856 EXPORT_SYMBOL_GPL(of_reconfig_notifier_register
);
1858 int of_reconfig_notifier_unregister(struct notifier_block
*nb
)
1860 return blocking_notifier_chain_unregister(&of_reconfig_chain
, nb
);
1862 EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister
);
1864 int of_reconfig_notify(unsigned long action
, void *p
)
1868 rc
= blocking_notifier_call_chain(&of_reconfig_chain
, action
, p
);
1869 return notifier_to_errno(rc
);
1873 * of_attach_node - Plug a device node into the tree and global list.
1875 int of_attach_node(struct device_node
*np
)
1877 unsigned long flags
;
1880 rc
= of_reconfig_notify(OF_RECONFIG_ATTACH_NODE
, np
);
1884 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1885 np
->sibling
= np
->parent
->child
;
1886 np
->allnext
= of_allnodes
;
1887 np
->parent
->child
= np
;
1889 of_node_clear_flag(np
, OF_DETACHED
);
1890 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1897 * of_detach_node - "Unplug" a node from the device tree.
1899 * The caller must hold a reference to the node. The memory associated with
1900 * the node is not freed until its refcount goes to zero.
1902 int of_detach_node(struct device_node
*np
)
1904 struct device_node
*parent
;
1905 unsigned long flags
;
1908 rc
= of_reconfig_notify(OF_RECONFIG_DETACH_NODE
, np
);
1912 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1914 if (of_node_check_flag(np
, OF_DETACHED
)) {
1915 /* someone already detached it */
1916 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1920 parent
= np
->parent
;
1922 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1926 if (of_allnodes
== np
)
1927 of_allnodes
= np
->allnext
;
1929 struct device_node
*prev
;
1930 for (prev
= of_allnodes
;
1931 prev
->allnext
!= np
;
1932 prev
= prev
->allnext
)
1934 prev
->allnext
= np
->allnext
;
1937 if (parent
->child
== np
)
1938 parent
->child
= np
->sibling
;
1940 struct device_node
*prevsib
;
1941 for (prevsib
= np
->parent
->child
;
1942 prevsib
->sibling
!= np
;
1943 prevsib
= prevsib
->sibling
)
1945 prevsib
->sibling
= np
->sibling
;
1948 of_node_set_flag(np
, OF_DETACHED
);
1949 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1954 #endif /* defined(CONFIG_OF_DYNAMIC) */
1956 static void of_alias_add(struct alias_prop
*ap
, struct device_node
*np
,
1957 int id
, const char *stem
, int stem_len
)
1961 strncpy(ap
->stem
, stem
, stem_len
);
1962 ap
->stem
[stem_len
] = 0;
1963 list_add_tail(&ap
->link
, &aliases_lookup
);
1964 pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
1965 ap
->alias
, ap
->stem
, ap
->id
, of_node_full_name(np
));
1969 * of_alias_scan - Scan all properties of 'aliases' node
1971 * The function scans all the properties of 'aliases' node and populate
1972 * the the global lookup table with the properties. It returns the
1973 * number of alias_prop found, or error code in error case.
1975 * @dt_alloc: An allocator that provides a virtual address to memory
1976 * for the resulting tree
1978 void of_alias_scan(void * (*dt_alloc
)(u64 size
, u64 align
))
1980 struct property
*pp
;
1982 of_chosen
= of_find_node_by_path("/chosen");
1983 if (of_chosen
== NULL
)
1984 of_chosen
= of_find_node_by_path("/chosen@0");
1987 const char *name
= of_get_property(of_chosen
, "stdout-path", NULL
);
1989 name
= of_get_property(of_chosen
, "linux,stdout-path", NULL
);
1991 of_stdout
= of_find_node_by_path(name
);
1994 of_aliases
= of_find_node_by_path("/aliases");
1998 for_each_property_of_node(of_aliases
, pp
) {
1999 const char *start
= pp
->name
;
2000 const char *end
= start
+ strlen(start
);
2001 struct device_node
*np
;
2002 struct alias_prop
*ap
;
2005 /* Skip those we do not want to proceed */
2006 if (!strcmp(pp
->name
, "name") ||
2007 !strcmp(pp
->name
, "phandle") ||
2008 !strcmp(pp
->name
, "linux,phandle"))
2011 np
= of_find_node_by_path(pp
->value
);
2015 /* walk the alias backwards to extract the id and work out
2016 * the 'stem' string */
2017 while (isdigit(*(end
-1)) && end
> start
)
2021 if (kstrtoint(end
, 10, &id
) < 0)
2024 /* Allocate an alias_prop with enough space for the stem */
2025 ap
= dt_alloc(sizeof(*ap
) + len
+ 1, 4);
2028 memset(ap
, 0, sizeof(*ap
) + len
+ 1);
2030 of_alias_add(ap
, np
, id
, start
, len
);
2035 * of_alias_get_id - Get alias id for the given device_node
2036 * @np: Pointer to the given device_node
2037 * @stem: Alias stem of the given device_node
2039 * The function travels the lookup table to get alias id for the given
2040 * device_node and alias stem. It returns the alias id if find it.
2042 int of_alias_get_id(struct device_node
*np
, const char *stem
)
2044 struct alias_prop
*app
;
2047 mutex_lock(&of_aliases_mutex
);
2048 list_for_each_entry(app
, &aliases_lookup
, link
) {
2049 if (strcmp(app
->stem
, stem
) != 0)
2052 if (np
== app
->np
) {
2057 mutex_unlock(&of_aliases_mutex
);
2061 EXPORT_SYMBOL_GPL(of_alias_get_id
);
2063 const __be32
*of_prop_next_u32(struct property
*prop
, const __be32
*cur
,
2066 const void *curv
= cur
;
2076 curv
+= sizeof(*cur
);
2077 if (curv
>= prop
->value
+ prop
->length
)
2081 *pu
= be32_to_cpup(curv
);
2084 EXPORT_SYMBOL_GPL(of_prop_next_u32
);
2086 const char *of_prop_next_string(struct property
*prop
, const char *cur
)
2088 const void *curv
= cur
;
2096 curv
+= strlen(cur
) + 1;
2097 if (curv
>= prop
->value
+ prop
->length
)
2102 EXPORT_SYMBOL_GPL(of_prop_next_string
);
2105 * of_device_is_stdout_path - check if a device node matches the
2106 * linux,stdout-path property
2108 * Check if this device node matches the linux,stdout-path property
2109 * in the chosen node. return true if yes, false otherwise.
2111 int of_device_is_stdout_path(struct device_node
*dn
)
2116 return of_stdout
== dn
;
2118 EXPORT_SYMBOL_GPL(of_device_is_stdout_path
);
2121 * of_find_next_cache_node - Find a node's subsidiary cache
2122 * @np: node of type "cpu" or "cache"
2124 * Returns a node pointer with refcount incremented, use
2125 * of_node_put() on it when done. Caller should hold a reference
2128 struct device_node
*of_find_next_cache_node(const struct device_node
*np
)
2130 struct device_node
*child
;
2131 const phandle
*handle
;
2133 handle
= of_get_property(np
, "l2-cache", NULL
);
2135 handle
= of_get_property(np
, "next-level-cache", NULL
);
2138 return of_find_node_by_phandle(be32_to_cpup(handle
));
2140 /* OF on pmac has nodes instead of properties named "l2-cache"
2141 * beneath CPU nodes.
2143 if (!strcmp(np
->type
, "cpu"))
2144 for_each_child_of_node(np
, child
)
2145 if (!strcmp(child
->type
, "cache"))
2152 * of_graph_parse_endpoint() - parse common endpoint node properties
2153 * @node: pointer to endpoint device_node
2154 * @endpoint: pointer to the OF endpoint data structure
2156 * The caller should hold a reference to @node.
2158 int of_graph_parse_endpoint(const struct device_node
*node
,
2159 struct of_endpoint
*endpoint
)
2161 struct device_node
*port_node
= of_get_parent(node
);
2163 WARN_ONCE(!port_node
, "%s(): endpoint %s has no parent node\n",
2164 __func__
, node
->full_name
);
2166 memset(endpoint
, 0, sizeof(*endpoint
));
2168 endpoint
->local_node
= node
;
2170 * It doesn't matter whether the two calls below succeed.
2171 * If they don't then the default value 0 is used.
2173 of_property_read_u32(port_node
, "reg", &endpoint
->port
);
2174 of_property_read_u32(node
, "reg", &endpoint
->id
);
2176 of_node_put(port_node
);
2180 EXPORT_SYMBOL(of_graph_parse_endpoint
);
2183 * of_graph_get_next_endpoint() - get next endpoint node
2184 * @parent: pointer to the parent device node
2185 * @prev: previous endpoint node, or NULL to get first
2187 * Return: An 'endpoint' node pointer with refcount incremented. Refcount
2188 * of the passed @prev node is not decremented, the caller have to use
2189 * of_node_put() on it when done.
2191 struct device_node
*of_graph_get_next_endpoint(const struct device_node
*parent
,
2192 struct device_node
*prev
)
2194 struct device_node
*endpoint
;
2195 struct device_node
*port
;
2201 * Start by locating the port node. If no previous endpoint is specified
2202 * search for the first port node, otherwise get the previous endpoint
2206 struct device_node
*node
;
2208 node
= of_get_child_by_name(parent
, "ports");
2212 port
= of_get_child_by_name(parent
, "port");
2216 pr_err("%s(): no port node found in %s\n",
2217 __func__
, parent
->full_name
);
2221 port
= of_get_parent(prev
);
2222 if (WARN_ONCE(!port
, "%s(): endpoint %s has no parent node\n",
2223 __func__
, prev
->full_name
))
2227 * Avoid dropping prev node refcount to 0 when getting the next
2235 * Now that we have a port node, get the next endpoint by
2236 * getting the next child. If the previous endpoint is NULL this
2237 * will return the first child.
2239 endpoint
= of_get_next_child(port
, prev
);
2245 /* No more endpoints under this port, try the next one. */
2249 port
= of_get_next_child(parent
, port
);
2252 } while (of_node_cmp(port
->name
, "port"));
2255 EXPORT_SYMBOL(of_graph_get_next_endpoint
);
2258 * of_graph_get_remote_port_parent() - get remote port's parent node
2259 * @node: pointer to a local endpoint device_node
2261 * Return: Remote device node associated with remote endpoint node linked
2262 * to @node. Use of_node_put() on it when done.
2264 struct device_node
*of_graph_get_remote_port_parent(
2265 const struct device_node
*node
)
2267 struct device_node
*np
;
2270 /* Get remote endpoint node. */
2271 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2273 /* Walk 3 levels up only if there is 'ports' node. */
2274 for (depth
= 3; depth
&& np
; depth
--) {
2275 np
= of_get_next_parent(np
);
2276 if (depth
== 2 && of_node_cmp(np
->name
, "ports"))
2281 EXPORT_SYMBOL(of_graph_get_remote_port_parent
);
2284 * of_graph_get_remote_port() - get remote port node
2285 * @node: pointer to a local endpoint device_node
2287 * Return: Remote port node associated with remote endpoint node linked
2288 * to @node. Use of_node_put() on it when done.
2290 struct device_node
*of_graph_get_remote_port(const struct device_node
*node
)
2292 struct device_node
*np
;
2294 /* Get remote endpoint node. */
2295 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2298 return of_get_next_parent(np
);
2300 EXPORT_SYMBOL(of_graph_get_remote_port
);