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
;
1027 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1028 for (np
= of_allnodes
; np
; np
= np
->allnext
)
1029 if (np
->phandle
== handle
)
1032 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1035 EXPORT_SYMBOL(of_find_node_by_phandle
);
1038 * of_property_count_elems_of_size - Count the number of elements in a property
1040 * @np: device node from which the property value is to be read.
1041 * @propname: name of the property to be searched.
1042 * @elem_size: size of the individual element
1044 * Search for a property in a device node and count the number of elements of
1045 * size elem_size in it. Returns number of elements on sucess, -EINVAL if the
1046 * property does not exist or its length does not match a multiple of elem_size
1047 * and -ENODATA if the property does not have a value.
1049 int of_property_count_elems_of_size(const struct device_node
*np
,
1050 const char *propname
, int elem_size
)
1052 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1059 if (prop
->length
% elem_size
!= 0) {
1060 pr_err("size of %s in node %s is not a multiple of %d\n",
1061 propname
, np
->full_name
, elem_size
);
1065 return prop
->length
/ elem_size
;
1067 EXPORT_SYMBOL_GPL(of_property_count_elems_of_size
);
1070 * of_find_property_value_of_size
1072 * @np: device node from which the property value is to be read.
1073 * @propname: name of the property to be searched.
1074 * @len: requested length of property value
1076 * Search for a property in a device node and valid the requested size.
1077 * Returns the property value on success, -EINVAL if the property does not
1078 * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
1079 * property data isn't large enough.
1082 static void *of_find_property_value_of_size(const struct device_node
*np
,
1083 const char *propname
, u32 len
)
1085 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1088 return ERR_PTR(-EINVAL
);
1090 return ERR_PTR(-ENODATA
);
1091 if (len
> prop
->length
)
1092 return ERR_PTR(-EOVERFLOW
);
1098 * of_property_read_u32_index - Find and read a u32 from a multi-value property.
1100 * @np: device node from which the property value is to be read.
1101 * @propname: name of the property to be searched.
1102 * @index: index of the u32 in the list of values
1103 * @out_value: pointer to return value, modified only if no error.
1105 * Search for a property in a device node and read nth 32-bit value from
1106 * it. Returns 0 on success, -EINVAL if the property does not exist,
1107 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1108 * property data isn't large enough.
1110 * The out_value is modified only if a valid u32 value can be decoded.
1112 int of_property_read_u32_index(const struct device_node
*np
,
1113 const char *propname
,
1114 u32 index
, u32
*out_value
)
1116 const u32
*val
= of_find_property_value_of_size(np
, propname
,
1117 ((index
+ 1) * sizeof(*out_value
)));
1120 return PTR_ERR(val
);
1122 *out_value
= be32_to_cpup(((__be32
*)val
) + index
);
1125 EXPORT_SYMBOL_GPL(of_property_read_u32_index
);
1128 * of_property_read_u8_array - Find and read an array of u8 from a property.
1130 * @np: device node from which the property value is to be read.
1131 * @propname: name of the property to be searched.
1132 * @out_values: pointer to return value, modified only if return value is 0.
1133 * @sz: number of array elements to read
1135 * Search for a property in a device node and read 8-bit value(s) from
1136 * it. Returns 0 on success, -EINVAL if the property does not exist,
1137 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1138 * property data isn't large enough.
1140 * dts entry of array should be like:
1141 * property = /bits/ 8 <0x50 0x60 0x70>;
1143 * The out_values is modified only if a valid u8 value can be decoded.
1145 int of_property_read_u8_array(const struct device_node
*np
,
1146 const char *propname
, u8
*out_values
, size_t sz
)
1148 const u8
*val
= of_find_property_value_of_size(np
, propname
,
1149 (sz
* sizeof(*out_values
)));
1152 return PTR_ERR(val
);
1155 *out_values
++ = *val
++;
1158 EXPORT_SYMBOL_GPL(of_property_read_u8_array
);
1161 * of_property_read_u16_array - Find and read an array of u16 from a property.
1163 * @np: device node from which the property value is to be read.
1164 * @propname: name of the property to be searched.
1165 * @out_values: pointer to return value, modified only if return value is 0.
1166 * @sz: number of array elements to read
1168 * Search for a property in a device node and read 16-bit value(s) from
1169 * it. Returns 0 on success, -EINVAL if the property does not exist,
1170 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1171 * property data isn't large enough.
1173 * dts entry of array should be like:
1174 * property = /bits/ 16 <0x5000 0x6000 0x7000>;
1176 * The out_values is modified only if a valid u16 value can be decoded.
1178 int of_property_read_u16_array(const struct device_node
*np
,
1179 const char *propname
, u16
*out_values
, size_t sz
)
1181 const __be16
*val
= of_find_property_value_of_size(np
, propname
,
1182 (sz
* sizeof(*out_values
)));
1185 return PTR_ERR(val
);
1188 *out_values
++ = be16_to_cpup(val
++);
1191 EXPORT_SYMBOL_GPL(of_property_read_u16_array
);
1194 * of_property_read_u32_array - Find and read an array of 32 bit integers
1197 * @np: device node from which the property value is to be read.
1198 * @propname: name of the property to be searched.
1199 * @out_values: pointer to return value, modified only if return value is 0.
1200 * @sz: number of array elements to read
1202 * Search for a property in a device node and read 32-bit value(s) from
1203 * it. Returns 0 on success, -EINVAL if the property does not exist,
1204 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1205 * property data isn't large enough.
1207 * The out_values is modified only if a valid u32 value can be decoded.
1209 int of_property_read_u32_array(const struct device_node
*np
,
1210 const char *propname
, u32
*out_values
,
1213 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1214 (sz
* sizeof(*out_values
)));
1217 return PTR_ERR(val
);
1220 *out_values
++ = be32_to_cpup(val
++);
1223 EXPORT_SYMBOL_GPL(of_property_read_u32_array
);
1226 * of_property_read_u64 - Find and read a 64 bit integer from a property
1227 * @np: device node from which the property value is to be read.
1228 * @propname: name of the property to be searched.
1229 * @out_value: pointer to return value, modified only if return value is 0.
1231 * Search for a property in a device node and read a 64-bit value from
1232 * it. Returns 0 on success, -EINVAL if the property does not exist,
1233 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1234 * property data isn't large enough.
1236 * The out_value is modified only if a valid u64 value can be decoded.
1238 int of_property_read_u64(const struct device_node
*np
, const char *propname
,
1241 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1242 sizeof(*out_value
));
1245 return PTR_ERR(val
);
1247 *out_value
= of_read_number(val
, 2);
1250 EXPORT_SYMBOL_GPL(of_property_read_u64
);
1253 * of_property_read_string - Find and read a string from a property
1254 * @np: device node from which the property value is to be read.
1255 * @propname: name of the property to be searched.
1256 * @out_string: pointer to null terminated return string, modified only if
1257 * return value is 0.
1259 * Search for a property in a device tree node and retrieve a null
1260 * terminated string value (pointer to data, not a copy). Returns 0 on
1261 * success, -EINVAL if the property does not exist, -ENODATA if property
1262 * does not have a value, and -EILSEQ if the string is not null-terminated
1263 * within the length of the property data.
1265 * The out_string pointer is modified only if a valid string can be decoded.
1267 int of_property_read_string(struct device_node
*np
, const char *propname
,
1268 const char **out_string
)
1270 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1275 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1277 *out_string
= prop
->value
;
1280 EXPORT_SYMBOL_GPL(of_property_read_string
);
1283 * of_property_read_string_index - Find and read a string from a multiple
1285 * @np: device node from which the property value is to be read.
1286 * @propname: name of the property to be searched.
1287 * @index: index of the string in the list of strings
1288 * @out_string: pointer to null terminated return string, modified only if
1289 * return value is 0.
1291 * Search for a property in a device tree node and retrieve a null
1292 * terminated string value (pointer to data, not a copy) in the list of strings
1293 * contained in that property.
1294 * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
1295 * property does not have a value, and -EILSEQ if the string is not
1296 * null-terminated within the length of the property data.
1298 * The out_string pointer is modified only if a valid string can be decoded.
1300 int of_property_read_string_index(struct device_node
*np
, const char *propname
,
1301 int index
, const char **output
)
1303 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1305 size_t l
= 0, total
= 0;
1312 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1317 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
) {
1326 EXPORT_SYMBOL_GPL(of_property_read_string_index
);
1329 * of_property_match_string() - Find string in a list and return index
1330 * @np: pointer to node containing string list property
1331 * @propname: string list property name
1332 * @string: pointer to string to search for in string list
1334 * This function searches a string list property and returns the index
1335 * of a specific string value.
1337 int of_property_match_string(struct device_node
*np
, const char *propname
,
1340 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1343 const char *p
, *end
;
1351 end
= p
+ prop
->length
;
1353 for (i
= 0; p
< end
; i
++, p
+= l
) {
1357 pr_debug("comparing %s with %s\n", string
, p
);
1358 if (strcmp(string
, p
) == 0)
1359 return i
; /* Found it; return index */
1363 EXPORT_SYMBOL_GPL(of_property_match_string
);
1366 * of_property_count_strings - Find and return the number of strings from a
1367 * multiple strings property.
1368 * @np: device node from which the property value is to be read.
1369 * @propname: name of the property to be searched.
1371 * Search for a property in a device tree node and retrieve the number of null
1372 * terminated string contain in it. Returns the number of strings on
1373 * success, -EINVAL if the property does not exist, -ENODATA if property
1374 * does not have a value, and -EILSEQ if the string is not null-terminated
1375 * within the length of the property data.
1377 int of_property_count_strings(struct device_node
*np
, const char *propname
)
1379 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1381 size_t l
= 0, total
= 0;
1388 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1393 for (i
= 0; total
< prop
->length
; total
+= l
, p
+= l
, i
++)
1398 EXPORT_SYMBOL_GPL(of_property_count_strings
);
1400 void of_print_phandle_args(const char *msg
, const struct of_phandle_args
*args
)
1403 printk("%s %s", msg
, of_node_full_name(args
->np
));
1404 for (i
= 0; i
< args
->args_count
; i
++)
1405 printk(i
? ",%08x" : ":%08x", args
->args
[i
]);
1409 static int __of_parse_phandle_with_args(const struct device_node
*np
,
1410 const char *list_name
,
1411 const char *cells_name
,
1412 int cell_count
, int index
,
1413 struct of_phandle_args
*out_args
)
1415 const __be32
*list
, *list_end
;
1416 int rc
= 0, size
, cur_index
= 0;
1418 struct device_node
*node
= NULL
;
1421 /* Retrieve the phandle list property */
1422 list
= of_get_property(np
, list_name
, &size
);
1425 list_end
= list
+ size
/ sizeof(*list
);
1427 /* Loop over the phandles until all the requested entry is found */
1428 while (list
< list_end
) {
1433 * If phandle is 0, then it is an empty entry with no
1434 * arguments. Skip forward to the next entry.
1436 phandle
= be32_to_cpup(list
++);
1439 * Find the provider node and parse the #*-cells
1440 * property to determine the argument length.
1442 * This is not needed if the cell count is hard-coded
1443 * (i.e. cells_name not set, but cell_count is set),
1444 * except when we're going to return the found node
1447 if (cells_name
|| cur_index
== index
) {
1448 node
= of_find_node_by_phandle(phandle
);
1450 pr_err("%s: could not find phandle\n",
1457 if (of_property_read_u32(node
, cells_name
,
1459 pr_err("%s: could not get %s for %s\n",
1460 np
->full_name
, cells_name
,
1469 * Make sure that the arguments actually fit in the
1470 * remaining property data length
1472 if (list
+ count
> list_end
) {
1473 pr_err("%s: arguments longer than property\n",
1480 * All of the error cases above bail out of the loop, so at
1481 * this point, the parsing is successful. If the requested
1482 * index matches, then fill the out_args structure and return,
1483 * or return -ENOENT for an empty entry.
1486 if (cur_index
== index
) {
1492 if (WARN_ON(count
> MAX_PHANDLE_ARGS
))
1493 count
= MAX_PHANDLE_ARGS
;
1494 out_args
->np
= node
;
1495 out_args
->args_count
= count
;
1496 for (i
= 0; i
< count
; i
++)
1497 out_args
->args
[i
] = be32_to_cpup(list
++);
1502 /* Found it! return success */
1513 * Unlock node before returning result; will be one of:
1514 * -ENOENT : index is for empty phandle
1515 * -EINVAL : parsing error on data
1516 * [1..n] : Number of phandle (count mode; when index = -1)
1518 rc
= index
< 0 ? cur_index
: -ENOENT
;
1526 * of_parse_phandle - Resolve a phandle property to a device_node pointer
1527 * @np: Pointer to device node holding phandle property
1528 * @phandle_name: Name of property holding a phandle value
1529 * @index: For properties holding a table of phandles, this is the index into
1532 * Returns the device_node pointer with refcount incremented. Use
1533 * of_node_put() on it when done.
1535 struct device_node
*of_parse_phandle(const struct device_node
*np
,
1536 const char *phandle_name
, int index
)
1538 struct of_phandle_args args
;
1543 if (__of_parse_phandle_with_args(np
, phandle_name
, NULL
, 0,
1549 EXPORT_SYMBOL(of_parse_phandle
);
1552 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
1553 * @np: pointer to a device tree node containing a list
1554 * @list_name: property name that contains a list
1555 * @cells_name: property name that specifies phandles' arguments count
1556 * @index: index of a phandle to parse out
1557 * @out_args: optional pointer to output arguments structure (will be filled)
1559 * This function is useful to parse lists of phandles and their arguments.
1560 * Returns 0 on success and fills out_args, on error returns appropriate
1563 * Caller is responsible to call of_node_put() on the returned out_args->node
1569 * #list-cells = <2>;
1573 * #list-cells = <1>;
1577 * list = <&phandle1 1 2 &phandle2 3>;
1580 * To get a device_node of the `node2' node you may call this:
1581 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
1583 int of_parse_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1584 const char *cells_name
, int index
,
1585 struct of_phandle_args
*out_args
)
1589 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0,
1592 EXPORT_SYMBOL(of_parse_phandle_with_args
);
1595 * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
1596 * @np: pointer to a device tree node containing a list
1597 * @list_name: property name that contains a list
1598 * @cell_count: number of argument cells following the phandle
1599 * @index: index of a phandle to parse out
1600 * @out_args: optional pointer to output arguments structure (will be filled)
1602 * This function is useful to parse lists of phandles and their arguments.
1603 * Returns 0 on success and fills out_args, on error returns appropriate
1606 * Caller is responsible to call of_node_put() on the returned out_args->node
1618 * list = <&phandle1 0 2 &phandle2 2 3>;
1621 * To get a device_node of the `node2' node you may call this:
1622 * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
1624 int of_parse_phandle_with_fixed_args(const struct device_node
*np
,
1625 const char *list_name
, int cell_count
,
1626 int index
, struct of_phandle_args
*out_args
)
1630 return __of_parse_phandle_with_args(np
, list_name
, NULL
, cell_count
,
1633 EXPORT_SYMBOL(of_parse_phandle_with_fixed_args
);
1636 * of_count_phandle_with_args() - Find the number of phandles references in a property
1637 * @np: pointer to a device tree node containing a list
1638 * @list_name: property name that contains a list
1639 * @cells_name: property name that specifies phandles' arguments count
1641 * Returns the number of phandle + argument tuples within a property. It
1642 * is a typical pattern to encode a list of phandle and variable
1643 * arguments into a single property. The number of arguments is encoded
1644 * by a property in the phandle-target node. For example, a gpios
1645 * property would contain a list of GPIO specifies consisting of a
1646 * phandle and 1 or more arguments. The number of arguments are
1647 * determined by the #gpio-cells property in the node pointed to by the
1650 int of_count_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1651 const char *cells_name
)
1653 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0, -1,
1656 EXPORT_SYMBOL(of_count_phandle_with_args
);
1659 * __of_add_property - Add a property to a node without lock operations
1661 int __of_add_property(struct device_node
*np
, struct property
*prop
)
1663 struct property
**next
;
1666 next
= &np
->properties
;
1668 if (strcmp(prop
->name
, (*next
)->name
) == 0)
1669 /* duplicate ! don't insert it */
1672 next
= &(*next
)->next
;
1680 * of_add_property - Add a property to a node
1682 int of_add_property(struct device_node
*np
, struct property
*prop
)
1684 unsigned long flags
;
1687 mutex_lock(&of_mutex
);
1689 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1690 rc
= __of_add_property(np
, prop
);
1691 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1694 __of_add_property_sysfs(np
, prop
);
1696 mutex_unlock(&of_mutex
);
1699 of_property_notify(OF_RECONFIG_ADD_PROPERTY
, np
, prop
, NULL
);
1704 int __of_remove_property(struct device_node
*np
, struct property
*prop
)
1706 struct property
**next
;
1708 for (next
= &np
->properties
; *next
; next
= &(*next
)->next
) {
1715 /* found the node */
1717 prop
->next
= np
->deadprops
;
1718 np
->deadprops
= prop
;
1723 void __of_remove_property_sysfs(struct device_node
*np
, struct property
*prop
)
1725 if (!IS_ENABLED(CONFIG_SYSFS
))
1728 /* at early boot, bail here and defer setup to of_init() */
1729 if (of_kset
&& of_node_is_attached(np
))
1730 sysfs_remove_bin_file(&np
->kobj
, &prop
->attr
);
1734 * of_remove_property - Remove a property from a node.
1736 * Note that we don't actually remove it, since we have given out
1737 * who-knows-how-many pointers to the data using get-property.
1738 * Instead we just move the property to the "dead properties"
1739 * list, so it won't be found any more.
1741 int of_remove_property(struct device_node
*np
, struct property
*prop
)
1743 unsigned long flags
;
1746 mutex_lock(&of_mutex
);
1748 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1749 rc
= __of_remove_property(np
, prop
);
1750 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1753 __of_remove_property_sysfs(np
, prop
);
1755 mutex_unlock(&of_mutex
);
1758 of_property_notify(OF_RECONFIG_REMOVE_PROPERTY
, np
, prop
, NULL
);
1763 int __of_update_property(struct device_node
*np
, struct property
*newprop
,
1764 struct property
**oldpropp
)
1766 struct property
**next
, *oldprop
;
1768 for (next
= &np
->properties
; *next
; next
= &(*next
)->next
) {
1769 if (of_prop_cmp((*next
)->name
, newprop
->name
) == 0)
1772 *oldpropp
= oldprop
= *next
;
1775 /* replace the node */
1776 newprop
->next
= oldprop
->next
;
1778 oldprop
->next
= np
->deadprops
;
1779 np
->deadprops
= oldprop
;
1782 newprop
->next
= NULL
;
1789 void __of_update_property_sysfs(struct device_node
*np
, struct property
*newprop
,
1790 struct property
*oldprop
)
1792 if (!IS_ENABLED(CONFIG_SYSFS
))
1795 /* At early boot, bail out and defer setup to of_init() */
1800 sysfs_remove_bin_file(&np
->kobj
, &oldprop
->attr
);
1801 __of_add_property_sysfs(np
, newprop
);
1805 * of_update_property - Update a property in a node, if the property does
1806 * not exist, add it.
1808 * Note that we don't actually remove it, since we have given out
1809 * who-knows-how-many pointers to the data using get-property.
1810 * Instead we just move the property to the "dead properties" list,
1811 * and add the new property to the property list
1813 int of_update_property(struct device_node
*np
, struct property
*newprop
)
1815 struct property
*oldprop
;
1816 unsigned long flags
;
1822 mutex_lock(&of_mutex
);
1824 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1825 rc
= __of_update_property(np
, newprop
, &oldprop
);
1826 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1829 __of_update_property_sysfs(np
, newprop
, oldprop
);
1831 mutex_unlock(&of_mutex
);
1834 of_property_notify(OF_RECONFIG_UPDATE_PROPERTY
, np
, newprop
, oldprop
);
1839 static void of_alias_add(struct alias_prop
*ap
, struct device_node
*np
,
1840 int id
, const char *stem
, int stem_len
)
1844 strncpy(ap
->stem
, stem
, stem_len
);
1845 ap
->stem
[stem_len
] = 0;
1846 list_add_tail(&ap
->link
, &aliases_lookup
);
1847 pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
1848 ap
->alias
, ap
->stem
, ap
->id
, of_node_full_name(np
));
1852 * of_alias_scan - Scan all properties of 'aliases' node
1854 * The function scans all the properties of 'aliases' node and populate
1855 * the the global lookup table with the properties. It returns the
1856 * number of alias_prop found, or error code in error case.
1858 * @dt_alloc: An allocator that provides a virtual address to memory
1859 * for the resulting tree
1861 void of_alias_scan(void * (*dt_alloc
)(u64 size
, u64 align
))
1863 struct property
*pp
;
1865 of_aliases
= of_find_node_by_path("/aliases");
1866 of_chosen
= of_find_node_by_path("/chosen");
1867 if (of_chosen
== NULL
)
1868 of_chosen
= of_find_node_by_path("/chosen@0");
1871 /* linux,stdout-path and /aliases/stdout are for legacy compatibility */
1872 const char *name
= of_get_property(of_chosen
, "stdout-path", NULL
);
1874 name
= of_get_property(of_chosen
, "linux,stdout-path", NULL
);
1875 if (IS_ENABLED(CONFIG_PPC
) && !name
)
1876 name
= of_get_property(of_aliases
, "stdout", NULL
);
1878 of_stdout
= of_find_node_by_path(name
);
1884 for_each_property_of_node(of_aliases
, pp
) {
1885 const char *start
= pp
->name
;
1886 const char *end
= start
+ strlen(start
);
1887 struct device_node
*np
;
1888 struct alias_prop
*ap
;
1891 /* Skip those we do not want to proceed */
1892 if (!strcmp(pp
->name
, "name") ||
1893 !strcmp(pp
->name
, "phandle") ||
1894 !strcmp(pp
->name
, "linux,phandle"))
1897 np
= of_find_node_by_path(pp
->value
);
1901 /* walk the alias backwards to extract the id and work out
1902 * the 'stem' string */
1903 while (isdigit(*(end
-1)) && end
> start
)
1907 if (kstrtoint(end
, 10, &id
) < 0)
1910 /* Allocate an alias_prop with enough space for the stem */
1911 ap
= dt_alloc(sizeof(*ap
) + len
+ 1, 4);
1914 memset(ap
, 0, sizeof(*ap
) + len
+ 1);
1916 of_alias_add(ap
, np
, id
, start
, len
);
1921 * of_alias_get_id - Get alias id for the given device_node
1922 * @np: Pointer to the given device_node
1923 * @stem: Alias stem of the given device_node
1925 * The function travels the lookup table to get the alias id for the given
1926 * device_node and alias stem. It returns the alias id if found.
1928 int of_alias_get_id(struct device_node
*np
, const char *stem
)
1930 struct alias_prop
*app
;
1933 mutex_lock(&of_mutex
);
1934 list_for_each_entry(app
, &aliases_lookup
, link
) {
1935 if (strcmp(app
->stem
, stem
) != 0)
1938 if (np
== app
->np
) {
1943 mutex_unlock(&of_mutex
);
1947 EXPORT_SYMBOL_GPL(of_alias_get_id
);
1949 const __be32
*of_prop_next_u32(struct property
*prop
, const __be32
*cur
,
1952 const void *curv
= cur
;
1962 curv
+= sizeof(*cur
);
1963 if (curv
>= prop
->value
+ prop
->length
)
1967 *pu
= be32_to_cpup(curv
);
1970 EXPORT_SYMBOL_GPL(of_prop_next_u32
);
1972 const char *of_prop_next_string(struct property
*prop
, const char *cur
)
1974 const void *curv
= cur
;
1982 curv
+= strlen(cur
) + 1;
1983 if (curv
>= prop
->value
+ prop
->length
)
1988 EXPORT_SYMBOL_GPL(of_prop_next_string
);
1991 * of_console_check() - Test and setup console for DT setup
1992 * @dn - Pointer to device node
1993 * @name - Name to use for preferred console without index. ex. "ttyS"
1994 * @index - Index to use for preferred console.
1996 * Check if the given device node matches the stdout-path property in the
1997 * /chosen node. If it does then register it as the preferred console and return
1998 * TRUE. Otherwise return FALSE.
2000 bool of_console_check(struct device_node
*dn
, char *name
, int index
)
2002 if (!dn
|| dn
!= of_stdout
|| console_set_on_cmdline
)
2004 return !add_preferred_console(name
, index
, NULL
);
2006 EXPORT_SYMBOL_GPL(of_console_check
);
2009 * of_find_next_cache_node - Find a node's subsidiary cache
2010 * @np: node of type "cpu" or "cache"
2012 * Returns a node pointer with refcount incremented, use
2013 * of_node_put() on it when done. Caller should hold a reference
2016 struct device_node
*of_find_next_cache_node(const struct device_node
*np
)
2018 struct device_node
*child
;
2019 const phandle
*handle
;
2021 handle
= of_get_property(np
, "l2-cache", NULL
);
2023 handle
= of_get_property(np
, "next-level-cache", NULL
);
2026 return of_find_node_by_phandle(be32_to_cpup(handle
));
2028 /* OF on pmac has nodes instead of properties named "l2-cache"
2029 * beneath CPU nodes.
2031 if (!strcmp(np
->type
, "cpu"))
2032 for_each_child_of_node(np
, child
)
2033 if (!strcmp(child
->type
, "cache"))
2040 * of_graph_parse_endpoint() - parse common endpoint node properties
2041 * @node: pointer to endpoint device_node
2042 * @endpoint: pointer to the OF endpoint data structure
2044 * The caller should hold a reference to @node.
2046 int of_graph_parse_endpoint(const struct device_node
*node
,
2047 struct of_endpoint
*endpoint
)
2049 struct device_node
*port_node
= of_get_parent(node
);
2051 WARN_ONCE(!port_node
, "%s(): endpoint %s has no parent node\n",
2052 __func__
, node
->full_name
);
2054 memset(endpoint
, 0, sizeof(*endpoint
));
2056 endpoint
->local_node
= node
;
2058 * It doesn't matter whether the two calls below succeed.
2059 * If they don't then the default value 0 is used.
2061 of_property_read_u32(port_node
, "reg", &endpoint
->port
);
2062 of_property_read_u32(node
, "reg", &endpoint
->id
);
2064 of_node_put(port_node
);
2068 EXPORT_SYMBOL(of_graph_parse_endpoint
);
2071 * of_graph_get_next_endpoint() - get next endpoint node
2072 * @parent: pointer to the parent device node
2073 * @prev: previous endpoint node, or NULL to get first
2075 * Return: An 'endpoint' node pointer with refcount incremented. Refcount
2076 * of the passed @prev node is not decremented, the caller have to use
2077 * of_node_put() on it when done.
2079 struct device_node
*of_graph_get_next_endpoint(const struct device_node
*parent
,
2080 struct device_node
*prev
)
2082 struct device_node
*endpoint
;
2083 struct device_node
*port
;
2089 * Start by locating the port node. If no previous endpoint is specified
2090 * search for the first port node, otherwise get the previous endpoint
2094 struct device_node
*node
;
2096 node
= of_get_child_by_name(parent
, "ports");
2100 port
= of_get_child_by_name(parent
, "port");
2104 pr_err("%s(): no port node found in %s\n",
2105 __func__
, parent
->full_name
);
2109 port
= of_get_parent(prev
);
2110 if (WARN_ONCE(!port
, "%s(): endpoint %s has no parent node\n",
2111 __func__
, prev
->full_name
))
2115 * Avoid dropping prev node refcount to 0 when getting the next
2123 * Now that we have a port node, get the next endpoint by
2124 * getting the next child. If the previous endpoint is NULL this
2125 * will return the first child.
2127 endpoint
= of_get_next_child(port
, prev
);
2133 /* No more endpoints under this port, try the next one. */
2137 port
= of_get_next_child(parent
, port
);
2140 } while (of_node_cmp(port
->name
, "port"));
2143 EXPORT_SYMBOL(of_graph_get_next_endpoint
);
2146 * of_graph_get_remote_port_parent() - get remote port's parent node
2147 * @node: pointer to a local endpoint device_node
2149 * Return: Remote device node associated with remote endpoint node linked
2150 * to @node. Use of_node_put() on it when done.
2152 struct device_node
*of_graph_get_remote_port_parent(
2153 const struct device_node
*node
)
2155 struct device_node
*np
;
2158 /* Get remote endpoint node. */
2159 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2161 /* Walk 3 levels up only if there is 'ports' node. */
2162 for (depth
= 3; depth
&& np
; depth
--) {
2163 np
= of_get_next_parent(np
);
2164 if (depth
== 2 && of_node_cmp(np
->name
, "ports"))
2169 EXPORT_SYMBOL(of_graph_get_remote_port_parent
);
2172 * of_graph_get_remote_port() - get remote port node
2173 * @node: pointer to a local endpoint device_node
2175 * Return: Remote port node associated with remote endpoint node linked
2176 * to @node. Use of_node_put() on it when done.
2178 struct device_node
*of_graph_get_remote_port(const struct device_node
*node
)
2180 struct device_node
*np
;
2182 /* Get remote endpoint node. */
2183 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2186 return of_get_next_parent(np
);
2188 EXPORT_SYMBOL(of_graph_get_remote_port
);