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/console.h>
21 #include <linux/ctype.h>
22 #include <linux/cpu.h>
23 #include <linux/module.h>
25 #include <linux/of_graph.h>
26 #include <linux/spinlock.h>
27 #include <linux/slab.h>
28 #include <linux/string.h>
29 #include <linux/proc_fs.h>
31 #include "of_private.h"
33 LIST_HEAD(aliases_lookup
);
35 struct device_node
*of_allnodes
;
36 EXPORT_SYMBOL(of_allnodes
);
37 struct device_node
*of_chosen
;
38 struct device_node
*of_aliases
;
39 struct device_node
*of_stdout
;
44 * Used to protect the of_aliases, to hold off addition of nodes to sysfs.
45 * This mutex must be held whenever modifications are being made to the
46 * device tree. The of_{attach,detach}_node() and
47 * of_{add,remove,update}_property() helpers make sure this happens.
49 DEFINE_MUTEX(of_mutex
);
51 /* use when traversing tree through the allnext, child, sibling,
52 * or parent members of struct device_node.
54 DEFINE_RAW_SPINLOCK(devtree_lock
);
56 int of_n_addr_cells(struct device_node
*np
)
63 ip
= of_get_property(np
, "#address-cells", NULL
);
65 return be32_to_cpup(ip
);
67 /* No #address-cells property for the root node */
68 return OF_ROOT_NODE_ADDR_CELLS_DEFAULT
;
70 EXPORT_SYMBOL(of_n_addr_cells
);
72 int of_n_size_cells(struct device_node
*np
)
79 ip
= of_get_property(np
, "#size-cells", NULL
);
81 return be32_to_cpup(ip
);
83 /* No #size-cells property for the root node */
84 return OF_ROOT_NODE_SIZE_CELLS_DEFAULT
;
86 EXPORT_SYMBOL(of_n_size_cells
);
89 int __weak
of_node_to_nid(struct device_node
*np
)
91 return numa_node_id();
95 #ifndef CONFIG_OF_DYNAMIC
96 static void of_node_release(struct kobject
*kobj
)
98 /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
100 #endif /* CONFIG_OF_DYNAMIC */
102 struct kobj_type of_node_ktype
= {
103 .release
= of_node_release
,
106 static ssize_t
of_node_property_read(struct file
*filp
, struct kobject
*kobj
,
107 struct bin_attribute
*bin_attr
, char *buf
,
108 loff_t offset
, size_t count
)
110 struct property
*pp
= container_of(bin_attr
, struct property
, attr
);
111 return memory_read_from_buffer(buf
, count
, &offset
, pp
->value
, pp
->length
);
114 static const char *safe_name(struct kobject
*kobj
, const char *orig_name
)
116 const char *name
= orig_name
;
117 struct kernfs_node
*kn
;
120 /* don't be a hero. After 16 tries give up */
121 while (i
< 16 && (kn
= sysfs_get_dirent(kobj
->sd
, name
))) {
123 if (name
!= orig_name
)
125 name
= kasprintf(GFP_KERNEL
, "%s#%i", orig_name
, ++i
);
128 if (name
!= orig_name
)
129 pr_warn("device-tree: Duplicate name in %s, renamed to \"%s\"\n",
130 kobject_name(kobj
), name
);
134 int __of_add_property_sysfs(struct device_node
*np
, struct property
*pp
)
138 /* Important: Don't leak passwords */
139 bool secure
= strncmp(pp
->name
, "security-", 9) == 0;
141 if (!IS_ENABLED(CONFIG_SYSFS
))
144 if (!of_kset
|| !of_node_is_attached(np
))
147 sysfs_bin_attr_init(&pp
->attr
);
148 pp
->attr
.attr
.name
= safe_name(&np
->kobj
, pp
->name
);
149 pp
->attr
.attr
.mode
= secure
? S_IRUSR
: S_IRUGO
;
150 pp
->attr
.size
= secure
? 0 : pp
->length
;
151 pp
->attr
.read
= of_node_property_read
;
153 rc
= sysfs_create_bin_file(&np
->kobj
, &pp
->attr
);
154 WARN(rc
, "error adding attribute %s to node %s\n", pp
->name
, np
->full_name
);
158 int __of_attach_node_sysfs(struct device_node
*np
)
164 if (!IS_ENABLED(CONFIG_SYSFS
))
170 np
->kobj
.kset
= of_kset
;
172 /* Nodes without parents are new top level trees */
173 rc
= kobject_add(&np
->kobj
, NULL
, "%s",
174 safe_name(&of_kset
->kobj
, "base"));
176 name
= safe_name(&np
->parent
->kobj
, kbasename(np
->full_name
));
177 if (!name
|| !name
[0])
180 rc
= kobject_add(&np
->kobj
, &np
->parent
->kobj
, "%s", name
);
185 for_each_property_of_node(np
, pp
)
186 __of_add_property_sysfs(np
, pp
);
191 static int __init
of_init(void)
193 struct device_node
*np
;
195 /* Create the kset, and register existing nodes */
196 mutex_lock(&of_mutex
);
197 of_kset
= kset_create_and_add("devicetree", NULL
, firmware_kobj
);
199 mutex_unlock(&of_mutex
);
202 for_each_of_allnodes(np
)
203 __of_attach_node_sysfs(np
);
204 mutex_unlock(&of_mutex
);
206 /* Symlink in /proc as required by userspace ABI */
208 proc_symlink("device-tree", NULL
, "/sys/firmware/devicetree/base");
212 core_initcall(of_init
);
214 static struct property
*__of_find_property(const struct device_node
*np
,
215 const char *name
, int *lenp
)
222 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
223 if (of_prop_cmp(pp
->name
, name
) == 0) {
233 struct property
*of_find_property(const struct device_node
*np
,
240 raw_spin_lock_irqsave(&devtree_lock
, flags
);
241 pp
= __of_find_property(np
, name
, lenp
);
242 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
246 EXPORT_SYMBOL(of_find_property
);
249 * of_find_all_nodes - Get next node in global list
250 * @prev: Previous node or NULL to start iteration
251 * of_node_put() will be called on it
253 * Returns a node pointer with refcount incremented, use
254 * of_node_put() on it when done.
256 struct device_node
*of_find_all_nodes(struct device_node
*prev
)
258 struct device_node
*np
;
261 raw_spin_lock_irqsave(&devtree_lock
, flags
);
262 np
= prev
? prev
->allnext
: of_allnodes
;
263 for (; np
!= NULL
; np
= np
->allnext
)
267 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
270 EXPORT_SYMBOL(of_find_all_nodes
);
273 * Find a property with a given name for a given node
274 * and return the value.
276 const void *__of_get_property(const struct device_node
*np
,
277 const char *name
, int *lenp
)
279 struct property
*pp
= __of_find_property(np
, name
, lenp
);
281 return pp
? pp
->value
: NULL
;
285 * Find a property with a given name for a given node
286 * and return the value.
288 const void *of_get_property(const struct device_node
*np
, const char *name
,
291 struct property
*pp
= of_find_property(np
, name
, lenp
);
293 return pp
? pp
->value
: NULL
;
295 EXPORT_SYMBOL(of_get_property
);
298 * arch_match_cpu_phys_id - Match the given logical CPU and physical id
300 * @cpu: logical cpu index of a core/thread
301 * @phys_id: physical identifier of a core/thread
303 * CPU logical to physical index mapping is architecture specific.
304 * However this __weak function provides a default match of physical
305 * id to logical cpu index. phys_id provided here is usually values read
306 * from the device tree which must match the hardware internal registers.
308 * Returns true if the physical identifier and the logical cpu index
309 * correspond to the same core/thread, false otherwise.
311 bool __weak
arch_match_cpu_phys_id(int cpu
, u64 phys_id
)
313 return (u32
)phys_id
== cpu
;
317 * Checks if the given "prop_name" property holds the physical id of the
318 * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
319 * NULL, local thread number within the core is returned in it.
321 static bool __of_find_n_match_cpu_property(struct device_node
*cpun
,
322 const char *prop_name
, int cpu
, unsigned int *thread
)
325 int ac
, prop_len
, tid
;
328 ac
= of_n_addr_cells(cpun
);
329 cell
= of_get_property(cpun
, prop_name
, &prop_len
);
332 prop_len
/= sizeof(*cell
) * ac
;
333 for (tid
= 0; tid
< prop_len
; tid
++) {
334 hwid
= of_read_number(cell
, ac
);
335 if (arch_match_cpu_phys_id(cpu
, hwid
)) {
346 * arch_find_n_match_cpu_physical_id - See if the given device node is
347 * for the cpu corresponding to logical cpu 'cpu'. Return true if so,
348 * else false. If 'thread' is non-NULL, the local thread number within the
349 * core is returned in it.
351 bool __weak
arch_find_n_match_cpu_physical_id(struct device_node
*cpun
,
352 int cpu
, unsigned int *thread
)
354 /* Check for non-standard "ibm,ppc-interrupt-server#s" property
355 * for thread ids on PowerPC. If it doesn't exist fallback to
356 * standard "reg" property.
358 if (IS_ENABLED(CONFIG_PPC
) &&
359 __of_find_n_match_cpu_property(cpun
,
360 "ibm,ppc-interrupt-server#s",
364 if (__of_find_n_match_cpu_property(cpun
, "reg", cpu
, thread
))
371 * of_get_cpu_node - Get device node associated with the given logical CPU
373 * @cpu: CPU number(logical index) for which device node is required
374 * @thread: if not NULL, local thread number within the physical core is
377 * The main purpose of this function is to retrieve the device node for the
378 * given logical CPU index. It should be used to initialize the of_node in
379 * cpu device. Once of_node in cpu device is populated, all the further
380 * references can use that instead.
382 * CPU logical to physical index mapping is architecture specific and is built
383 * before booting secondary cores. This function uses arch_match_cpu_phys_id
384 * which can be overridden by architecture specific implementation.
386 * Returns a node pointer for the logical cpu if found, else NULL.
388 struct device_node
*of_get_cpu_node(int cpu
, unsigned int *thread
)
390 struct device_node
*cpun
;
392 for_each_node_by_type(cpun
, "cpu") {
393 if (arch_find_n_match_cpu_physical_id(cpun
, cpu
, thread
))
398 EXPORT_SYMBOL(of_get_cpu_node
);
401 * __of_device_is_compatible() - Check if the node matches given constraints
402 * @device: pointer to node
403 * @compat: required compatible string, NULL or "" for any match
404 * @type: required device_type value, NULL or "" for any match
405 * @name: required node name, NULL or "" for any match
407 * Checks if the given @compat, @type and @name strings match the
408 * properties of the given @device. A constraints can be skipped by
409 * passing NULL or an empty string as the constraint.
411 * Returns 0 for no match, and a positive integer on match. The return
412 * value is a relative score with larger values indicating better
413 * matches. The score is weighted for the most specific compatible value
414 * to get the highest score. Matching type is next, followed by matching
415 * name. Practically speaking, this results in the following priority
418 * 1. specific compatible && type && name
419 * 2. specific compatible && type
420 * 3. specific compatible && name
421 * 4. specific compatible
422 * 5. general compatible && type && name
423 * 6. general compatible && type
424 * 7. general compatible && name
425 * 8. general compatible
430 static int __of_device_is_compatible(const struct device_node
*device
,
431 const char *compat
, const char *type
, const char *name
)
433 struct property
*prop
;
435 int index
= 0, score
= 0;
437 /* Compatible match has highest priority */
438 if (compat
&& compat
[0]) {
439 prop
= __of_find_property(device
, "compatible", NULL
);
440 for (cp
= of_prop_next_string(prop
, NULL
); cp
;
441 cp
= of_prop_next_string(prop
, cp
), index
++) {
442 if (of_compat_cmp(cp
, compat
, strlen(compat
)) == 0) {
443 score
= INT_MAX
/2 - (index
<< 2);
451 /* Matching type is better than matching name */
452 if (type
&& type
[0]) {
453 if (!device
->type
|| of_node_cmp(type
, device
->type
))
458 /* Matching name is a bit better than not */
459 if (name
&& name
[0]) {
460 if (!device
->name
|| of_node_cmp(name
, device
->name
))
468 /** Checks if the given "compat" string matches one of the strings in
469 * the device's "compatible" property
471 int of_device_is_compatible(const struct device_node
*device
,
477 raw_spin_lock_irqsave(&devtree_lock
, flags
);
478 res
= __of_device_is_compatible(device
, compat
, NULL
, NULL
);
479 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
482 EXPORT_SYMBOL(of_device_is_compatible
);
485 * of_machine_is_compatible - Test root of device tree for a given compatible value
486 * @compat: compatible string to look for in root node's compatible property.
488 * Returns true if the root node has the given value in its
489 * compatible property.
491 int of_machine_is_compatible(const char *compat
)
493 struct device_node
*root
;
496 root
= of_find_node_by_path("/");
498 rc
= of_device_is_compatible(root
, compat
);
503 EXPORT_SYMBOL(of_machine_is_compatible
);
506 * __of_device_is_available - check if a device is available for use
508 * @device: Node to check for availability, with locks already held
510 * Returns 1 if the status property is absent or set to "okay" or "ok",
513 static int __of_device_is_available(const struct device_node
*device
)
521 status
= __of_get_property(device
, "status", &statlen
);
526 if (!strcmp(status
, "okay") || !strcmp(status
, "ok"))
534 * of_device_is_available - check if a device is available for use
536 * @device: Node to check for availability
538 * Returns 1 if the status property is absent or set to "okay" or "ok",
541 int of_device_is_available(const struct device_node
*device
)
546 raw_spin_lock_irqsave(&devtree_lock
, flags
);
547 res
= __of_device_is_available(device
);
548 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
552 EXPORT_SYMBOL(of_device_is_available
);
555 * of_get_parent - Get a node's parent if any
556 * @node: Node to get parent
558 * Returns a node pointer with refcount incremented, use
559 * of_node_put() on it when done.
561 struct device_node
*of_get_parent(const struct device_node
*node
)
563 struct device_node
*np
;
569 raw_spin_lock_irqsave(&devtree_lock
, flags
);
570 np
= of_node_get(node
->parent
);
571 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
574 EXPORT_SYMBOL(of_get_parent
);
577 * of_get_next_parent - Iterate to a node's parent
578 * @node: Node to get parent of
580 * This is like of_get_parent() except that it drops the
581 * refcount on the passed node, making it suitable for iterating
582 * through a node's parents.
584 * Returns a node pointer with refcount incremented, use
585 * of_node_put() on it when done.
587 struct device_node
*of_get_next_parent(struct device_node
*node
)
589 struct device_node
*parent
;
595 raw_spin_lock_irqsave(&devtree_lock
, flags
);
596 parent
= of_node_get(node
->parent
);
598 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
601 EXPORT_SYMBOL(of_get_next_parent
);
603 static struct device_node
*__of_get_next_child(const struct device_node
*node
,
604 struct device_node
*prev
)
606 struct device_node
*next
;
611 next
= prev
? prev
->sibling
: node
->child
;
612 for (; next
; next
= next
->sibling
)
613 if (of_node_get(next
))
618 #define __for_each_child_of_node(parent, child) \
619 for (child = __of_get_next_child(parent, NULL); child != NULL; \
620 child = __of_get_next_child(parent, child))
623 * of_get_next_child - Iterate a node childs
625 * @prev: previous child of the parent node, or NULL to get first
627 * Returns a node pointer with refcount incremented, use
628 * of_node_put() on it when done.
630 struct device_node
*of_get_next_child(const struct device_node
*node
,
631 struct device_node
*prev
)
633 struct device_node
*next
;
636 raw_spin_lock_irqsave(&devtree_lock
, flags
);
637 next
= __of_get_next_child(node
, prev
);
638 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
641 EXPORT_SYMBOL(of_get_next_child
);
644 * of_get_next_available_child - Find the next available child node
646 * @prev: previous child of the parent node, or NULL to get first
648 * This function is like of_get_next_child(), except that it
649 * automatically skips any disabled nodes (i.e. status = "disabled").
651 struct device_node
*of_get_next_available_child(const struct device_node
*node
,
652 struct device_node
*prev
)
654 struct device_node
*next
;
660 raw_spin_lock_irqsave(&devtree_lock
, flags
);
661 next
= prev
? prev
->sibling
: node
->child
;
662 for (; next
; next
= next
->sibling
) {
663 if (!__of_device_is_available(next
))
665 if (of_node_get(next
))
669 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
672 EXPORT_SYMBOL(of_get_next_available_child
);
675 * of_get_child_by_name - Find the child node by name for a given parent
677 * @name: child name to look for.
679 * This function looks for child node for given matching name
681 * Returns a node pointer if found, with refcount incremented, use
682 * of_node_put() on it when done.
683 * Returns NULL if node is not found.
685 struct device_node
*of_get_child_by_name(const struct device_node
*node
,
688 struct device_node
*child
;
690 for_each_child_of_node(node
, child
)
691 if (child
->name
&& (of_node_cmp(child
->name
, name
) == 0))
695 EXPORT_SYMBOL(of_get_child_by_name
);
697 static struct device_node
*__of_find_node_by_path(struct device_node
*parent
,
700 struct device_node
*child
;
701 int len
= strchrnul(path
, '/') - path
;
706 __for_each_child_of_node(parent
, child
) {
707 const char *name
= strrchr(child
->full_name
, '/');
708 if (WARN(!name
, "malformed device_node %s\n", child
->full_name
))
711 if (strncmp(path
, name
, len
) == 0 && (strlen(name
) == len
))
718 * of_find_node_by_path - Find a node matching a full OF path
719 * @path: Either the full path to match, or if the path does not
720 * start with '/', the name of a property of the /aliases
721 * node (an alias). In the case of an alias, the node
722 * matching the alias' value will be returned.
727 * foo/bar Valid alias + relative path
729 * Returns a node pointer with refcount incremented, use
730 * of_node_put() on it when done.
732 struct device_node
*of_find_node_by_path(const char *path
)
734 struct device_node
*np
= NULL
;
738 if (strcmp(path
, "/") == 0)
739 return of_node_get(of_allnodes
);
741 /* The path could begin with an alias */
743 char *p
= strchrnul(path
, '/');
746 /* of_aliases must not be NULL */
750 for_each_property_of_node(of_aliases
, pp
) {
751 if (strlen(pp
->name
) == len
&& !strncmp(pp
->name
, path
, len
)) {
752 np
= of_find_node_by_path(pp
->value
);
761 /* Step down the tree matching path components */
762 raw_spin_lock_irqsave(&devtree_lock
, flags
);
764 np
= of_node_get(of_allnodes
);
765 while (np
&& *path
== '/') {
766 path
++; /* Increment past '/' delimiter */
767 np
= __of_find_node_by_path(np
, path
);
768 path
= strchrnul(path
, '/');
770 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
773 EXPORT_SYMBOL(of_find_node_by_path
);
776 * of_find_node_by_name - Find a node by its "name" property
777 * @from: The node to start searching from or NULL, the node
778 * you pass will not be searched, only the next one
779 * will; typically, you pass what the previous call
780 * returned. of_node_put() will be called on it
781 * @name: The name string to match against
783 * Returns a node pointer with refcount incremented, use
784 * of_node_put() on it when done.
786 struct device_node
*of_find_node_by_name(struct device_node
*from
,
789 struct device_node
*np
;
792 raw_spin_lock_irqsave(&devtree_lock
, flags
);
793 np
= from
? from
->allnext
: of_allnodes
;
794 for (; np
; np
= np
->allnext
)
795 if (np
->name
&& (of_node_cmp(np
->name
, name
) == 0)
799 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
802 EXPORT_SYMBOL(of_find_node_by_name
);
805 * of_find_node_by_type - Find a node by its "device_type" property
806 * @from: The node to start searching from, or NULL to start searching
807 * the entire device tree. The node you pass will not be
808 * searched, only the next one will; typically, you pass
809 * what the previous call returned. of_node_put() will be
810 * called on from for you.
811 * @type: The type string to match against
813 * Returns a node pointer with refcount incremented, use
814 * of_node_put() on it when done.
816 struct device_node
*of_find_node_by_type(struct device_node
*from
,
819 struct device_node
*np
;
822 raw_spin_lock_irqsave(&devtree_lock
, flags
);
823 np
= from
? from
->allnext
: of_allnodes
;
824 for (; np
; np
= np
->allnext
)
825 if (np
->type
&& (of_node_cmp(np
->type
, type
) == 0)
829 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
832 EXPORT_SYMBOL(of_find_node_by_type
);
835 * of_find_compatible_node - Find a node based on type and one of the
836 * tokens in its "compatible" property
837 * @from: The node to start searching from or NULL, the node
838 * you pass will not be searched, only the next one
839 * will; typically, you pass what the previous call
840 * returned. of_node_put() will be called on it
841 * @type: The type string to match "device_type" or NULL to ignore
842 * @compatible: The string to match to one of the tokens in the device
845 * Returns a node pointer with refcount incremented, use
846 * of_node_put() on it when done.
848 struct device_node
*of_find_compatible_node(struct device_node
*from
,
849 const char *type
, const char *compatible
)
851 struct device_node
*np
;
854 raw_spin_lock_irqsave(&devtree_lock
, flags
);
855 np
= from
? from
->allnext
: of_allnodes
;
856 for (; np
; np
= np
->allnext
) {
857 if (__of_device_is_compatible(np
, compatible
, type
, NULL
) &&
862 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
865 EXPORT_SYMBOL(of_find_compatible_node
);
868 * of_find_node_with_property - Find a node which has a property with
870 * @from: The node to start searching from or NULL, the node
871 * you pass will not be searched, only the next one
872 * will; typically, you pass what the previous call
873 * returned. of_node_put() will be called on it
874 * @prop_name: The name of the property to look for.
876 * Returns a node pointer with refcount incremented, use
877 * of_node_put() on it when done.
879 struct device_node
*of_find_node_with_property(struct device_node
*from
,
880 const char *prop_name
)
882 struct device_node
*np
;
886 raw_spin_lock_irqsave(&devtree_lock
, flags
);
887 np
= from
? from
->allnext
: of_allnodes
;
888 for (; np
; np
= np
->allnext
) {
889 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
890 if (of_prop_cmp(pp
->name
, prop_name
) == 0) {
898 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
901 EXPORT_SYMBOL(of_find_node_with_property
);
904 const struct of_device_id
*__of_match_node(const struct of_device_id
*matches
,
905 const struct device_node
*node
)
907 const struct of_device_id
*best_match
= NULL
;
908 int score
, best_score
= 0;
913 for (; matches
->name
[0] || matches
->type
[0] || matches
->compatible
[0]; matches
++) {
914 score
= __of_device_is_compatible(node
, matches
->compatible
,
915 matches
->type
, matches
->name
);
916 if (score
> best_score
) {
917 best_match
= matches
;
926 * of_match_node - Tell if an device_node has a matching of_match structure
927 * @matches: array of of device match structures to search in
928 * @node: the of device structure to match against
930 * Low level utility function used by device matching.
932 const struct of_device_id
*of_match_node(const struct of_device_id
*matches
,
933 const struct device_node
*node
)
935 const struct of_device_id
*match
;
938 raw_spin_lock_irqsave(&devtree_lock
, flags
);
939 match
= __of_match_node(matches
, node
);
940 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
943 EXPORT_SYMBOL(of_match_node
);
946 * of_find_matching_node_and_match - Find a node based on an of_device_id
948 * @from: The node to start searching from or NULL, the node
949 * you pass will not be searched, only the next one
950 * will; typically, you pass what the previous call
951 * returned. of_node_put() will be called on it
952 * @matches: array of of device match structures to search in
953 * @match Updated to point at the matches entry which matched
955 * Returns a node pointer with refcount incremented, use
956 * of_node_put() on it when done.
958 struct device_node
*of_find_matching_node_and_match(struct device_node
*from
,
959 const struct of_device_id
*matches
,
960 const struct of_device_id
**match
)
962 struct device_node
*np
;
963 const struct of_device_id
*m
;
969 raw_spin_lock_irqsave(&devtree_lock
, flags
);
970 np
= from
? from
->allnext
: of_allnodes
;
971 for (; np
; np
= np
->allnext
) {
972 m
= __of_match_node(matches
, np
);
973 if (m
&& of_node_get(np
)) {
980 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
983 EXPORT_SYMBOL(of_find_matching_node_and_match
);
986 * of_modalias_node - Lookup appropriate modalias for a device node
987 * @node: pointer to a device tree node
988 * @modalias: Pointer to buffer that modalias value will be copied into
989 * @len: Length of modalias value
991 * Based on the value of the compatible property, this routine will attempt
992 * to choose an appropriate modalias value for a particular device tree node.
993 * It does this by stripping the manufacturer prefix (as delimited by a ',')
994 * from the first entry in the compatible list property.
996 * This routine returns 0 on success, <0 on failure.
998 int of_modalias_node(struct device_node
*node
, char *modalias
, int len
)
1000 const char *compatible
, *p
;
1003 compatible
= of_get_property(node
, "compatible", &cplen
);
1004 if (!compatible
|| strlen(compatible
) > cplen
)
1006 p
= strchr(compatible
, ',');
1007 strlcpy(modalias
, p
? p
+ 1 : compatible
, len
);
1010 EXPORT_SYMBOL_GPL(of_modalias_node
);
1013 * of_find_node_by_phandle - Find a node given a phandle
1014 * @handle: phandle of the node to find
1016 * Returns a node pointer with refcount incremented, use
1017 * of_node_put() on it when done.
1019 struct device_node
*of_find_node_by_phandle(phandle handle
)
1021 struct device_node
*np
;
1022 unsigned long flags
;
1024 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1025 for (np
= of_allnodes
; np
; np
= np
->allnext
)
1026 if (np
->phandle
== handle
)
1029 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1032 EXPORT_SYMBOL(of_find_node_by_phandle
);
1035 * of_property_count_elems_of_size - Count the number of elements in a property
1037 * @np: device node from which the property value is to be read.
1038 * @propname: name of the property to be searched.
1039 * @elem_size: size of the individual element
1041 * Search for a property in a device node and count the number of elements of
1042 * size elem_size in it. Returns number of elements on sucess, -EINVAL if the
1043 * property does not exist or its length does not match a multiple of elem_size
1044 * and -ENODATA if the property does not have a value.
1046 int of_property_count_elems_of_size(const struct device_node
*np
,
1047 const char *propname
, int elem_size
)
1049 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1056 if (prop
->length
% elem_size
!= 0) {
1057 pr_err("size of %s in node %s is not a multiple of %d\n",
1058 propname
, np
->full_name
, elem_size
);
1062 return prop
->length
/ elem_size
;
1064 EXPORT_SYMBOL_GPL(of_property_count_elems_of_size
);
1067 * of_find_property_value_of_size
1069 * @np: device node from which the property value is to be read.
1070 * @propname: name of the property to be searched.
1071 * @len: requested length of property value
1073 * Search for a property in a device node and valid the requested size.
1074 * Returns the property value on success, -EINVAL if the property does not
1075 * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
1076 * property data isn't large enough.
1079 static void *of_find_property_value_of_size(const struct device_node
*np
,
1080 const char *propname
, u32 len
)
1082 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1085 return ERR_PTR(-EINVAL
);
1087 return ERR_PTR(-ENODATA
);
1088 if (len
> prop
->length
)
1089 return ERR_PTR(-EOVERFLOW
);
1095 * of_property_read_u32_index - Find and read a u32 from a multi-value property.
1097 * @np: device node from which the property value is to be read.
1098 * @propname: name of the property to be searched.
1099 * @index: index of the u32 in the list of values
1100 * @out_value: pointer to return value, modified only if no error.
1102 * Search for a property in a device node and read nth 32-bit value from
1103 * it. Returns 0 on success, -EINVAL if the property does not exist,
1104 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1105 * property data isn't large enough.
1107 * The out_value is modified only if a valid u32 value can be decoded.
1109 int of_property_read_u32_index(const struct device_node
*np
,
1110 const char *propname
,
1111 u32 index
, u32
*out_value
)
1113 const u32
*val
= of_find_property_value_of_size(np
, propname
,
1114 ((index
+ 1) * sizeof(*out_value
)));
1117 return PTR_ERR(val
);
1119 *out_value
= be32_to_cpup(((__be32
*)val
) + index
);
1122 EXPORT_SYMBOL_GPL(of_property_read_u32_index
);
1125 * of_property_read_u8_array - Find and read an array of u8 from a property.
1127 * @np: device node from which the property value is to be read.
1128 * @propname: name of the property to be searched.
1129 * @out_values: pointer to return value, modified only if return value is 0.
1130 * @sz: number of array elements to read
1132 * Search for a property in a device node and read 8-bit value(s) from
1133 * it. Returns 0 on success, -EINVAL if the property does not exist,
1134 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1135 * property data isn't large enough.
1137 * dts entry of array should be like:
1138 * property = /bits/ 8 <0x50 0x60 0x70>;
1140 * The out_values is modified only if a valid u8 value can be decoded.
1142 int of_property_read_u8_array(const struct device_node
*np
,
1143 const char *propname
, u8
*out_values
, size_t sz
)
1145 const u8
*val
= of_find_property_value_of_size(np
, propname
,
1146 (sz
* sizeof(*out_values
)));
1149 return PTR_ERR(val
);
1152 *out_values
++ = *val
++;
1155 EXPORT_SYMBOL_GPL(of_property_read_u8_array
);
1158 * of_property_read_u16_array - Find and read an array of u16 from a property.
1160 * @np: device node from which the property value is to be read.
1161 * @propname: name of the property to be searched.
1162 * @out_values: pointer to return value, modified only if return value is 0.
1163 * @sz: number of array elements to read
1165 * Search for a property in a device node and read 16-bit value(s) from
1166 * it. Returns 0 on success, -EINVAL if the property does not exist,
1167 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1168 * property data isn't large enough.
1170 * dts entry of array should be like:
1171 * property = /bits/ 16 <0x5000 0x6000 0x7000>;
1173 * The out_values is modified only if a valid u16 value can be decoded.
1175 int of_property_read_u16_array(const struct device_node
*np
,
1176 const char *propname
, u16
*out_values
, size_t sz
)
1178 const __be16
*val
= of_find_property_value_of_size(np
, propname
,
1179 (sz
* sizeof(*out_values
)));
1182 return PTR_ERR(val
);
1185 *out_values
++ = be16_to_cpup(val
++);
1188 EXPORT_SYMBOL_GPL(of_property_read_u16_array
);
1191 * of_property_read_u32_array - Find and read an array of 32 bit integers
1194 * @np: device node from which the property value is to be read.
1195 * @propname: name of the property to be searched.
1196 * @out_values: pointer to return value, modified only if return value is 0.
1197 * @sz: number of array elements to read
1199 * Search for a property in a device node and read 32-bit value(s) from
1200 * it. Returns 0 on success, -EINVAL if the property does not exist,
1201 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1202 * property data isn't large enough.
1204 * The out_values is modified only if a valid u32 value can be decoded.
1206 int of_property_read_u32_array(const struct device_node
*np
,
1207 const char *propname
, u32
*out_values
,
1210 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1211 (sz
* sizeof(*out_values
)));
1214 return PTR_ERR(val
);
1217 *out_values
++ = be32_to_cpup(val
++);
1220 EXPORT_SYMBOL_GPL(of_property_read_u32_array
);
1223 * of_property_read_u64 - Find and read a 64 bit integer from a property
1224 * @np: device node from which the property value is to be read.
1225 * @propname: name of the property to be searched.
1226 * @out_value: pointer to return value, modified only if return value is 0.
1228 * Search for a property in a device node and read a 64-bit value from
1229 * it. Returns 0 on success, -EINVAL if the property does not exist,
1230 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1231 * property data isn't large enough.
1233 * The out_value is modified only if a valid u64 value can be decoded.
1235 int of_property_read_u64(const struct device_node
*np
, const char *propname
,
1238 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1239 sizeof(*out_value
));
1242 return PTR_ERR(val
);
1244 *out_value
= of_read_number(val
, 2);
1247 EXPORT_SYMBOL_GPL(of_property_read_u64
);
1250 * of_property_read_string - Find and read a string from a property
1251 * @np: device node from which the property value is to be read.
1252 * @propname: name of the property to be searched.
1253 * @out_string: pointer to null terminated return string, modified only if
1254 * return value is 0.
1256 * Search for a property in a device tree node and retrieve a null
1257 * terminated string value (pointer to data, not a copy). Returns 0 on
1258 * success, -EINVAL if the property does not exist, -ENODATA if property
1259 * does not have a value, and -EILSEQ if the string is not null-terminated
1260 * within the length of the property data.
1262 * The out_string pointer is modified only if a valid string can be decoded.
1264 int of_property_read_string(struct device_node
*np
, const char *propname
,
1265 const char **out_string
)
1267 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1272 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1274 *out_string
= prop
->value
;
1277 EXPORT_SYMBOL_GPL(of_property_read_string
);
1280 * of_property_read_string_index - Find and read a string from a multiple
1282 * @np: device node from which the property value is to be read.
1283 * @propname: name of the property to be searched.
1284 * @index: index of the string in the list of strings
1285 * @out_string: pointer to null terminated return string, modified only if
1286 * return value is 0.
1288 * Search for a property in a device tree node and retrieve a null
1289 * terminated string value (pointer to data, not a copy) in the list of strings
1290 * contained in that property.
1291 * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
1292 * property does not have a value, and -EILSEQ if the string is not
1293 * null-terminated within the length of the property data.
1295 * The out_string pointer is modified only if a valid string can be decoded.
1297 int of_property_read_string_index(struct device_node
*np
, const char *propname
,
1298 int index
, const char **output
)
1300 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1302 size_t l
= 0, total
= 0;
1309 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1314 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
) {
1323 EXPORT_SYMBOL_GPL(of_property_read_string_index
);
1326 * of_property_match_string() - Find string in a list and return index
1327 * @np: pointer to node containing string list property
1328 * @propname: string list property name
1329 * @string: pointer to string to search for in string list
1331 * This function searches a string list property and returns the index
1332 * of a specific string value.
1334 int of_property_match_string(struct device_node
*np
, const char *propname
,
1337 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1340 const char *p
, *end
;
1348 end
= p
+ prop
->length
;
1350 for (i
= 0; p
< end
; i
++, p
+= l
) {
1354 pr_debug("comparing %s with %s\n", string
, p
);
1355 if (strcmp(string
, p
) == 0)
1356 return i
; /* Found it; return index */
1360 EXPORT_SYMBOL_GPL(of_property_match_string
);
1363 * of_property_count_strings - Find and return the number of strings from a
1364 * multiple strings property.
1365 * @np: device node from which the property value is to be read.
1366 * @propname: name of the property to be searched.
1368 * Search for a property in a device tree node and retrieve the number of null
1369 * terminated string contain in it. Returns the number of strings on
1370 * success, -EINVAL if the property does not exist, -ENODATA if property
1371 * does not have a value, and -EILSEQ if the string is not null-terminated
1372 * within the length of the property data.
1374 int of_property_count_strings(struct device_node
*np
, const char *propname
)
1376 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1378 size_t l
= 0, total
= 0;
1385 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1390 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
, i
++)
1395 EXPORT_SYMBOL_GPL(of_property_count_strings
);
1397 void of_print_phandle_args(const char *msg
, const struct of_phandle_args
*args
)
1400 printk("%s %s", msg
, of_node_full_name(args
->np
));
1401 for (i
= 0; i
< args
->args_count
; i
++)
1402 printk(i
? ",%08x" : ":%08x", args
->args
[i
]);
1406 static int __of_parse_phandle_with_args(const struct device_node
*np
,
1407 const char *list_name
,
1408 const char *cells_name
,
1409 int cell_count
, int index
,
1410 struct of_phandle_args
*out_args
)
1412 const __be32
*list
, *list_end
;
1413 int rc
= 0, size
, cur_index
= 0;
1415 struct device_node
*node
= NULL
;
1418 /* Retrieve the phandle list property */
1419 list
= of_get_property(np
, list_name
, &size
);
1422 list_end
= list
+ size
/ sizeof(*list
);
1424 /* Loop over the phandles until all the requested entry is found */
1425 while (list
< list_end
) {
1430 * If phandle is 0, then it is an empty entry with no
1431 * arguments. Skip forward to the next entry.
1433 phandle
= be32_to_cpup(list
++);
1436 * Find the provider node and parse the #*-cells
1437 * property to determine the argument length.
1439 * This is not needed if the cell count is hard-coded
1440 * (i.e. cells_name not set, but cell_count is set),
1441 * except when we're going to return the found node
1444 if (cells_name
|| cur_index
== index
) {
1445 node
= of_find_node_by_phandle(phandle
);
1447 pr_err("%s: could not find phandle\n",
1454 if (of_property_read_u32(node
, cells_name
,
1456 pr_err("%s: could not get %s for %s\n",
1457 np
->full_name
, cells_name
,
1466 * Make sure that the arguments actually fit in the
1467 * remaining property data length
1469 if (list
+ count
> list_end
) {
1470 pr_err("%s: arguments longer than property\n",
1477 * All of the error cases above bail out of the loop, so at
1478 * this point, the parsing is successful. If the requested
1479 * index matches, then fill the out_args structure and return,
1480 * or return -ENOENT for an empty entry.
1483 if (cur_index
== index
) {
1489 if (WARN_ON(count
> MAX_PHANDLE_ARGS
))
1490 count
= MAX_PHANDLE_ARGS
;
1491 out_args
->np
= node
;
1492 out_args
->args_count
= count
;
1493 for (i
= 0; i
< count
; i
++)
1494 out_args
->args
[i
] = be32_to_cpup(list
++);
1499 /* Found it! return success */
1510 * Unlock node before returning result; will be one of:
1511 * -ENOENT : index is for empty phandle
1512 * -EINVAL : parsing error on data
1513 * [1..n] : Number of phandle (count mode; when index = -1)
1515 rc
= index
< 0 ? cur_index
: -ENOENT
;
1523 * of_parse_phandle - Resolve a phandle property to a device_node pointer
1524 * @np: Pointer to device node holding phandle property
1525 * @phandle_name: Name of property holding a phandle value
1526 * @index: For properties holding a table of phandles, this is the index into
1529 * Returns the device_node pointer with refcount incremented. Use
1530 * of_node_put() on it when done.
1532 struct device_node
*of_parse_phandle(const struct device_node
*np
,
1533 const char *phandle_name
, int index
)
1535 struct of_phandle_args args
;
1540 if (__of_parse_phandle_with_args(np
, phandle_name
, NULL
, 0,
1546 EXPORT_SYMBOL(of_parse_phandle
);
1549 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
1550 * @np: pointer to a device tree node containing a list
1551 * @list_name: property name that contains a list
1552 * @cells_name: property name that specifies phandles' arguments count
1553 * @index: index of a phandle to parse out
1554 * @out_args: optional pointer to output arguments structure (will be filled)
1556 * This function is useful to parse lists of phandles and their arguments.
1557 * Returns 0 on success and fills out_args, on error returns appropriate
1560 * Caller is responsible to call of_node_put() on the returned out_args->node
1566 * #list-cells = <2>;
1570 * #list-cells = <1>;
1574 * list = <&phandle1 1 2 &phandle2 3>;
1577 * To get a device_node of the `node2' node you may call this:
1578 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
1580 int of_parse_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1581 const char *cells_name
, int index
,
1582 struct of_phandle_args
*out_args
)
1586 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0,
1589 EXPORT_SYMBOL(of_parse_phandle_with_args
);
1592 * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
1593 * @np: pointer to a device tree node containing a list
1594 * @list_name: property name that contains a list
1595 * @cell_count: number of argument cells following the phandle
1596 * @index: index of a phandle to parse out
1597 * @out_args: optional pointer to output arguments structure (will be filled)
1599 * This function is useful to parse lists of phandles and their arguments.
1600 * Returns 0 on success and fills out_args, on error returns appropriate
1603 * Caller is responsible to call of_node_put() on the returned out_args->node
1615 * list = <&phandle1 0 2 &phandle2 2 3>;
1618 * To get a device_node of the `node2' node you may call this:
1619 * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
1621 int of_parse_phandle_with_fixed_args(const struct device_node
*np
,
1622 const char *list_name
, int cell_count
,
1623 int index
, struct of_phandle_args
*out_args
)
1627 return __of_parse_phandle_with_args(np
, list_name
, NULL
, cell_count
,
1630 EXPORT_SYMBOL(of_parse_phandle_with_fixed_args
);
1633 * of_count_phandle_with_args() - Find the number of phandles references in a property
1634 * @np: pointer to a device tree node containing a list
1635 * @list_name: property name that contains a list
1636 * @cells_name: property name that specifies phandles' arguments count
1638 * Returns the number of phandle + argument tuples within a property. It
1639 * is a typical pattern to encode a list of phandle and variable
1640 * arguments into a single property. The number of arguments is encoded
1641 * by a property in the phandle-target node. For example, a gpios
1642 * property would contain a list of GPIO specifies consisting of a
1643 * phandle and 1 or more arguments. The number of arguments are
1644 * determined by the #gpio-cells property in the node pointed to by the
1647 int of_count_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1648 const char *cells_name
)
1650 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0, -1,
1653 EXPORT_SYMBOL(of_count_phandle_with_args
);
1656 * __of_add_property - Add a property to a node without lock operations
1658 int __of_add_property(struct device_node
*np
, struct property
*prop
)
1660 struct property
**next
;
1663 next
= &np
->properties
;
1665 if (strcmp(prop
->name
, (*next
)->name
) == 0)
1666 /* duplicate ! don't insert it */
1669 next
= &(*next
)->next
;
1677 * of_add_property - Add a property to a node
1679 int of_add_property(struct device_node
*np
, struct property
*prop
)
1681 unsigned long flags
;
1684 mutex_lock(&of_mutex
);
1686 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1687 rc
= __of_add_property(np
, prop
);
1688 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1691 __of_add_property_sysfs(np
, prop
);
1693 mutex_unlock(&of_mutex
);
1696 of_property_notify(OF_RECONFIG_ADD_PROPERTY
, np
, prop
, NULL
);
1701 int __of_remove_property(struct device_node
*np
, struct property
*prop
)
1703 struct property
**next
;
1705 for (next
= &np
->properties
; *next
; next
= &(*next
)->next
) {
1712 /* found the node */
1714 prop
->next
= np
->deadprops
;
1715 np
->deadprops
= prop
;
1720 void __of_remove_property_sysfs(struct device_node
*np
, struct property
*prop
)
1722 if (!IS_ENABLED(CONFIG_SYSFS
))
1725 /* at early boot, bail here and defer setup to of_init() */
1726 if (of_kset
&& of_node_is_attached(np
))
1727 sysfs_remove_bin_file(&np
->kobj
, &prop
->attr
);
1731 * of_remove_property - Remove a property from a node.
1733 * Note that we don't actually remove it, since we have given out
1734 * who-knows-how-many pointers to the data using get-property.
1735 * Instead we just move the property to the "dead properties"
1736 * list, so it won't be found any more.
1738 int of_remove_property(struct device_node
*np
, struct property
*prop
)
1740 unsigned long flags
;
1743 mutex_lock(&of_mutex
);
1745 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1746 rc
= __of_remove_property(np
, prop
);
1747 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1750 __of_remove_property_sysfs(np
, prop
);
1752 mutex_unlock(&of_mutex
);
1755 of_property_notify(OF_RECONFIG_REMOVE_PROPERTY
, np
, prop
, NULL
);
1760 int __of_update_property(struct device_node
*np
, struct property
*newprop
,
1761 struct property
**oldpropp
)
1763 struct property
**next
, *oldprop
;
1765 for (next
= &np
->properties
; *next
; next
= &(*next
)->next
) {
1766 if (of_prop_cmp((*next
)->name
, newprop
->name
) == 0)
1769 *oldpropp
= oldprop
= *next
;
1772 /* replace the node */
1773 newprop
->next
= oldprop
->next
;
1775 oldprop
->next
= np
->deadprops
;
1776 np
->deadprops
= oldprop
;
1779 newprop
->next
= NULL
;
1786 void __of_update_property_sysfs(struct device_node
*np
, struct property
*newprop
,
1787 struct property
*oldprop
)
1789 if (!IS_ENABLED(CONFIG_SYSFS
))
1792 /* At early boot, bail out and defer setup to of_init() */
1797 sysfs_remove_bin_file(&np
->kobj
, &oldprop
->attr
);
1798 __of_add_property_sysfs(np
, newprop
);
1802 * of_update_property - Update a property in a node, if the property does
1803 * not exist, add it.
1805 * Note that we don't actually remove it, since we have given out
1806 * who-knows-how-many pointers to the data using get-property.
1807 * Instead we just move the property to the "dead properties" list,
1808 * and add the new property to the property list
1810 int of_update_property(struct device_node
*np
, struct property
*newprop
)
1812 struct property
*oldprop
;
1813 unsigned long flags
;
1819 mutex_lock(&of_mutex
);
1821 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1822 rc
= __of_update_property(np
, newprop
, &oldprop
);
1823 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1826 __of_update_property_sysfs(np
, newprop
, oldprop
);
1828 mutex_unlock(&of_mutex
);
1831 of_property_notify(OF_RECONFIG_UPDATE_PROPERTY
, np
, newprop
, oldprop
);
1836 static void of_alias_add(struct alias_prop
*ap
, struct device_node
*np
,
1837 int id
, const char *stem
, int stem_len
)
1841 strncpy(ap
->stem
, stem
, stem_len
);
1842 ap
->stem
[stem_len
] = 0;
1843 list_add_tail(&ap
->link
, &aliases_lookup
);
1844 pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
1845 ap
->alias
, ap
->stem
, ap
->id
, of_node_full_name(np
));
1849 * of_alias_scan - Scan all properties of 'aliases' node
1851 * The function scans all the properties of 'aliases' node and populate
1852 * the the global lookup table with the properties. It returns the
1853 * number of alias_prop found, or error code in error case.
1855 * @dt_alloc: An allocator that provides a virtual address to memory
1856 * for the resulting tree
1858 void of_alias_scan(void * (*dt_alloc
)(u64 size
, u64 align
))
1860 struct property
*pp
;
1862 of_aliases
= of_find_node_by_path("/aliases");
1863 of_chosen
= of_find_node_by_path("/chosen");
1864 if (of_chosen
== NULL
)
1865 of_chosen
= of_find_node_by_path("/chosen@0");
1868 /* linux,stdout-path and /aliases/stdout are for legacy compatibility */
1869 const char *name
= of_get_property(of_chosen
, "stdout-path", NULL
);
1871 name
= of_get_property(of_chosen
, "linux,stdout-path", NULL
);
1872 if (IS_ENABLED(CONFIG_PPC
) && !name
)
1873 name
= of_get_property(of_aliases
, "stdout", NULL
);
1875 of_stdout
= of_find_node_by_path(name
);
1881 for_each_property_of_node(of_aliases
, pp
) {
1882 const char *start
= pp
->name
;
1883 const char *end
= start
+ strlen(start
);
1884 struct device_node
*np
;
1885 struct alias_prop
*ap
;
1888 /* Skip those we do not want to proceed */
1889 if (!strcmp(pp
->name
, "name") ||
1890 !strcmp(pp
->name
, "phandle") ||
1891 !strcmp(pp
->name
, "linux,phandle"))
1894 np
= of_find_node_by_path(pp
->value
);
1898 /* walk the alias backwards to extract the id and work out
1899 * the 'stem' string */
1900 while (isdigit(*(end
-1)) && end
> start
)
1904 if (kstrtoint(end
, 10, &id
) < 0)
1907 /* Allocate an alias_prop with enough space for the stem */
1908 ap
= dt_alloc(sizeof(*ap
) + len
+ 1, 4);
1911 memset(ap
, 0, sizeof(*ap
) + len
+ 1);
1913 of_alias_add(ap
, np
, id
, start
, len
);
1918 * of_alias_get_id - Get alias id for the given device_node
1919 * @np: Pointer to the given device_node
1920 * @stem: Alias stem of the given device_node
1922 * The function travels the lookup table to get the alias id for the given
1923 * device_node and alias stem. It returns the alias id if found.
1925 int of_alias_get_id(struct device_node
*np
, const char *stem
)
1927 struct alias_prop
*app
;
1930 mutex_lock(&of_mutex
);
1931 list_for_each_entry(app
, &aliases_lookup
, link
) {
1932 if (strcmp(app
->stem
, stem
) != 0)
1935 if (np
== app
->np
) {
1940 mutex_unlock(&of_mutex
);
1944 EXPORT_SYMBOL_GPL(of_alias_get_id
);
1946 const __be32
*of_prop_next_u32(struct property
*prop
, const __be32
*cur
,
1949 const void *curv
= cur
;
1959 curv
+= sizeof(*cur
);
1960 if (curv
>= prop
->value
+ prop
->length
)
1964 *pu
= be32_to_cpup(curv
);
1967 EXPORT_SYMBOL_GPL(of_prop_next_u32
);
1969 const char *of_prop_next_string(struct property
*prop
, const char *cur
)
1971 const void *curv
= cur
;
1979 curv
+= strlen(cur
) + 1;
1980 if (curv
>= prop
->value
+ prop
->length
)
1985 EXPORT_SYMBOL_GPL(of_prop_next_string
);
1988 * of_console_check() - Test and setup console for DT setup
1989 * @dn - Pointer to device node
1990 * @name - Name to use for preferred console without index. ex. "ttyS"
1991 * @index - Index to use for preferred console.
1993 * Check if the given device node matches the stdout-path property in the
1994 * /chosen node. If it does then register it as the preferred console and return
1995 * TRUE. Otherwise return FALSE.
1997 bool of_console_check(struct device_node
*dn
, char *name
, int index
)
1999 if (!dn
|| dn
!= of_stdout
|| console_set_on_cmdline
)
2001 return !add_preferred_console(name
, index
, NULL
);
2003 EXPORT_SYMBOL_GPL(of_console_check
);
2006 * of_find_next_cache_node - Find a node's subsidiary cache
2007 * @np: node of type "cpu" or "cache"
2009 * Returns a node pointer with refcount incremented, use
2010 * of_node_put() on it when done. Caller should hold a reference
2013 struct device_node
*of_find_next_cache_node(const struct device_node
*np
)
2015 struct device_node
*child
;
2016 const phandle
*handle
;
2018 handle
= of_get_property(np
, "l2-cache", NULL
);
2020 handle
= of_get_property(np
, "next-level-cache", NULL
);
2023 return of_find_node_by_phandle(be32_to_cpup(handle
));
2025 /* OF on pmac has nodes instead of properties named "l2-cache"
2026 * beneath CPU nodes.
2028 if (!strcmp(np
->type
, "cpu"))
2029 for_each_child_of_node(np
, child
)
2030 if (!strcmp(child
->type
, "cache"))
2037 * of_graph_parse_endpoint() - parse common endpoint node properties
2038 * @node: pointer to endpoint device_node
2039 * @endpoint: pointer to the OF endpoint data structure
2041 * The caller should hold a reference to @node.
2043 int of_graph_parse_endpoint(const struct device_node
*node
,
2044 struct of_endpoint
*endpoint
)
2046 struct device_node
*port_node
= of_get_parent(node
);
2048 WARN_ONCE(!port_node
, "%s(): endpoint %s has no parent node\n",
2049 __func__
, node
->full_name
);
2051 memset(endpoint
, 0, sizeof(*endpoint
));
2053 endpoint
->local_node
= node
;
2055 * It doesn't matter whether the two calls below succeed.
2056 * If they don't then the default value 0 is used.
2058 of_property_read_u32(port_node
, "reg", &endpoint
->port
);
2059 of_property_read_u32(node
, "reg", &endpoint
->id
);
2061 of_node_put(port_node
);
2065 EXPORT_SYMBOL(of_graph_parse_endpoint
);
2068 * of_graph_get_next_endpoint() - get next endpoint node
2069 * @parent: pointer to the parent device node
2070 * @prev: previous endpoint node, or NULL to get first
2072 * Return: An 'endpoint' node pointer with refcount incremented. Refcount
2073 * of the passed @prev node is not decremented, the caller have to use
2074 * of_node_put() on it when done.
2076 struct device_node
*of_graph_get_next_endpoint(const struct device_node
*parent
,
2077 struct device_node
*prev
)
2079 struct device_node
*endpoint
;
2080 struct device_node
*port
;
2086 * Start by locating the port node. If no previous endpoint is specified
2087 * search for the first port node, otherwise get the previous endpoint
2091 struct device_node
*node
;
2093 node
= of_get_child_by_name(parent
, "ports");
2097 port
= of_get_child_by_name(parent
, "port");
2101 pr_err("%s(): no port node found in %s\n",
2102 __func__
, parent
->full_name
);
2106 port
= of_get_parent(prev
);
2107 if (WARN_ONCE(!port
, "%s(): endpoint %s has no parent node\n",
2108 __func__
, prev
->full_name
))
2112 * Avoid dropping prev node refcount to 0 when getting the next
2120 * Now that we have a port node, get the next endpoint by
2121 * getting the next child. If the previous endpoint is NULL this
2122 * will return the first child.
2124 endpoint
= of_get_next_child(port
, prev
);
2130 /* No more endpoints under this port, try the next one. */
2134 port
= of_get_next_child(parent
, port
);
2137 } while (of_node_cmp(port
->name
, "port"));
2140 EXPORT_SYMBOL(of_graph_get_next_endpoint
);
2143 * of_graph_get_remote_port_parent() - get remote port's parent node
2144 * @node: pointer to a local endpoint device_node
2146 * Return: Remote device node associated with remote endpoint node linked
2147 * to @node. Use of_node_put() on it when done.
2149 struct device_node
*of_graph_get_remote_port_parent(
2150 const struct device_node
*node
)
2152 struct device_node
*np
;
2155 /* Get remote endpoint node. */
2156 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2158 /* Walk 3 levels up only if there is 'ports' node. */
2159 for (depth
= 3; depth
&& np
; depth
--) {
2160 np
= of_get_next_parent(np
);
2161 if (depth
== 2 && of_node_cmp(np
->name
, "ports"))
2166 EXPORT_SYMBOL(of_graph_get_remote_port_parent
);
2169 * of_graph_get_remote_port() - get remote port node
2170 * @node: pointer to a local endpoint device_node
2172 * Return: Remote port node associated with remote endpoint node linked
2173 * to @node. Use of_node_put() on it when done.
2175 struct device_node
*of_graph_get_remote_port(const struct device_node
*node
)
2177 struct device_node
*np
;
2179 /* Get remote endpoint node. */
2180 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2183 return of_get_next_parent(np
);
2185 EXPORT_SYMBOL(of_graph_get_remote_port
);