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_root
;
36 EXPORT_SYMBOL(of_root
);
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 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
);
248 struct device_node
*__of_find_all_nodes(struct device_node
*prev
)
250 struct device_node
*np
;
253 } else if (prev
->child
) {
256 /* Walk back up looking for a sibling, or the end of the structure */
258 while (np
->parent
&& !np
->sibling
)
260 np
= np
->sibling
; /* Might be null at the end of the tree */
266 * of_find_all_nodes - Get next node in global list
267 * @prev: Previous node or NULL to start iteration
268 * of_node_put() will be called on it
270 * Returns a node pointer with refcount incremented, use
271 * of_node_put() on it when done.
273 struct device_node
*of_find_all_nodes(struct device_node
*prev
)
275 struct device_node
*np
;
278 raw_spin_lock_irqsave(&devtree_lock
, flags
);
279 np
= __of_find_all_nodes(prev
);
282 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
285 EXPORT_SYMBOL(of_find_all_nodes
);
288 * Find a property with a given name for a given node
289 * and return the value.
291 const void *__of_get_property(const struct device_node
*np
,
292 const char *name
, int *lenp
)
294 struct property
*pp
= __of_find_property(np
, name
, lenp
);
296 return pp
? pp
->value
: NULL
;
300 * Find a property with a given name for a given node
301 * and return the value.
303 const void *of_get_property(const struct device_node
*np
, const char *name
,
306 struct property
*pp
= of_find_property(np
, name
, lenp
);
308 return pp
? pp
->value
: NULL
;
310 EXPORT_SYMBOL(of_get_property
);
313 * arch_match_cpu_phys_id - Match the given logical CPU and physical id
315 * @cpu: logical cpu index of a core/thread
316 * @phys_id: physical identifier of a core/thread
318 * CPU logical to physical index mapping is architecture specific.
319 * However this __weak function provides a default match of physical
320 * id to logical cpu index. phys_id provided here is usually values read
321 * from the device tree which must match the hardware internal registers.
323 * Returns true if the physical identifier and the logical cpu index
324 * correspond to the same core/thread, false otherwise.
326 bool __weak
arch_match_cpu_phys_id(int cpu
, u64 phys_id
)
328 return (u32
)phys_id
== cpu
;
332 * Checks if the given "prop_name" property holds the physical id of the
333 * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
334 * NULL, local thread number within the core is returned in it.
336 static bool __of_find_n_match_cpu_property(struct device_node
*cpun
,
337 const char *prop_name
, int cpu
, unsigned int *thread
)
340 int ac
, prop_len
, tid
;
343 ac
= of_n_addr_cells(cpun
);
344 cell
= of_get_property(cpun
, prop_name
, &prop_len
);
347 prop_len
/= sizeof(*cell
) * ac
;
348 for (tid
= 0; tid
< prop_len
; tid
++) {
349 hwid
= of_read_number(cell
, ac
);
350 if (arch_match_cpu_phys_id(cpu
, hwid
)) {
361 * arch_find_n_match_cpu_physical_id - See if the given device node is
362 * for the cpu corresponding to logical cpu 'cpu'. Return true if so,
363 * else false. If 'thread' is non-NULL, the local thread number within the
364 * core is returned in it.
366 bool __weak
arch_find_n_match_cpu_physical_id(struct device_node
*cpun
,
367 int cpu
, unsigned int *thread
)
369 /* Check for non-standard "ibm,ppc-interrupt-server#s" property
370 * for thread ids on PowerPC. If it doesn't exist fallback to
371 * standard "reg" property.
373 if (IS_ENABLED(CONFIG_PPC
) &&
374 __of_find_n_match_cpu_property(cpun
,
375 "ibm,ppc-interrupt-server#s",
379 if (__of_find_n_match_cpu_property(cpun
, "reg", cpu
, thread
))
386 * of_get_cpu_node - Get device node associated with the given logical CPU
388 * @cpu: CPU number(logical index) for which device node is required
389 * @thread: if not NULL, local thread number within the physical core is
392 * The main purpose of this function is to retrieve the device node for the
393 * given logical CPU index. It should be used to initialize the of_node in
394 * cpu device. Once of_node in cpu device is populated, all the further
395 * references can use that instead.
397 * CPU logical to physical index mapping is architecture specific and is built
398 * before booting secondary cores. This function uses arch_match_cpu_phys_id
399 * which can be overridden by architecture specific implementation.
401 * Returns a node pointer for the logical cpu if found, else NULL.
403 struct device_node
*of_get_cpu_node(int cpu
, unsigned int *thread
)
405 struct device_node
*cpun
;
407 for_each_node_by_type(cpun
, "cpu") {
408 if (arch_find_n_match_cpu_physical_id(cpun
, cpu
, thread
))
413 EXPORT_SYMBOL(of_get_cpu_node
);
416 * __of_device_is_compatible() - Check if the node matches given constraints
417 * @device: pointer to node
418 * @compat: required compatible string, NULL or "" for any match
419 * @type: required device_type value, NULL or "" for any match
420 * @name: required node name, NULL or "" for any match
422 * Checks if the given @compat, @type and @name strings match the
423 * properties of the given @device. A constraints can be skipped by
424 * passing NULL or an empty string as the constraint.
426 * Returns 0 for no match, and a positive integer on match. The return
427 * value is a relative score with larger values indicating better
428 * matches. The score is weighted for the most specific compatible value
429 * to get the highest score. Matching type is next, followed by matching
430 * name. Practically speaking, this results in the following priority
433 * 1. specific compatible && type && name
434 * 2. specific compatible && type
435 * 3. specific compatible && name
436 * 4. specific compatible
437 * 5. general compatible && type && name
438 * 6. general compatible && type
439 * 7. general compatible && name
440 * 8. general compatible
445 static int __of_device_is_compatible(const struct device_node
*device
,
446 const char *compat
, const char *type
, const char *name
)
448 struct property
*prop
;
450 int index
= 0, score
= 0;
452 /* Compatible match has highest priority */
453 if (compat
&& compat
[0]) {
454 prop
= __of_find_property(device
, "compatible", NULL
);
455 for (cp
= of_prop_next_string(prop
, NULL
); cp
;
456 cp
= of_prop_next_string(prop
, cp
), index
++) {
457 if (of_compat_cmp(cp
, compat
, strlen(compat
)) == 0) {
458 score
= INT_MAX
/2 - (index
<< 2);
466 /* Matching type is better than matching name */
467 if (type
&& type
[0]) {
468 if (!device
->type
|| of_node_cmp(type
, device
->type
))
473 /* Matching name is a bit better than not */
474 if (name
&& name
[0]) {
475 if (!device
->name
|| of_node_cmp(name
, device
->name
))
483 /** Checks if the given "compat" string matches one of the strings in
484 * the device's "compatible" property
486 int of_device_is_compatible(const struct device_node
*device
,
492 raw_spin_lock_irqsave(&devtree_lock
, flags
);
493 res
= __of_device_is_compatible(device
, compat
, NULL
, NULL
);
494 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
497 EXPORT_SYMBOL(of_device_is_compatible
);
500 * of_machine_is_compatible - Test root of device tree for a given compatible value
501 * @compat: compatible string to look for in root node's compatible property.
503 * Returns true if the root node has the given value in its
504 * compatible property.
506 int of_machine_is_compatible(const char *compat
)
508 struct device_node
*root
;
511 root
= of_find_node_by_path("/");
513 rc
= of_device_is_compatible(root
, compat
);
518 EXPORT_SYMBOL(of_machine_is_compatible
);
521 * __of_device_is_available - check if a device is available for use
523 * @device: Node to check for availability, with locks already held
525 * Returns 1 if the status property is absent or set to "okay" or "ok",
528 static int __of_device_is_available(const struct device_node
*device
)
536 status
= __of_get_property(device
, "status", &statlen
);
541 if (!strcmp(status
, "okay") || !strcmp(status
, "ok"))
549 * of_device_is_available - check if a device is available for use
551 * @device: Node to check for availability
553 * Returns 1 if the status property is absent or set to "okay" or "ok",
556 int of_device_is_available(const struct device_node
*device
)
561 raw_spin_lock_irqsave(&devtree_lock
, flags
);
562 res
= __of_device_is_available(device
);
563 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
567 EXPORT_SYMBOL(of_device_is_available
);
570 * of_get_parent - Get a node's parent if any
571 * @node: Node to get parent
573 * Returns a node pointer with refcount incremented, use
574 * of_node_put() on it when done.
576 struct device_node
*of_get_parent(const struct device_node
*node
)
578 struct device_node
*np
;
584 raw_spin_lock_irqsave(&devtree_lock
, flags
);
585 np
= of_node_get(node
->parent
);
586 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
589 EXPORT_SYMBOL(of_get_parent
);
592 * of_get_next_parent - Iterate to a node's parent
593 * @node: Node to get parent of
595 * This is like of_get_parent() except that it drops the
596 * refcount on the passed node, making it suitable for iterating
597 * through a node's parents.
599 * Returns a node pointer with refcount incremented, use
600 * of_node_put() on it when done.
602 struct device_node
*of_get_next_parent(struct device_node
*node
)
604 struct device_node
*parent
;
610 raw_spin_lock_irqsave(&devtree_lock
, flags
);
611 parent
= of_node_get(node
->parent
);
613 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
616 EXPORT_SYMBOL(of_get_next_parent
);
618 static struct device_node
*__of_get_next_child(const struct device_node
*node
,
619 struct device_node
*prev
)
621 struct device_node
*next
;
626 next
= prev
? prev
->sibling
: node
->child
;
627 for (; next
; next
= next
->sibling
)
628 if (of_node_get(next
))
633 #define __for_each_child_of_node(parent, child) \
634 for (child = __of_get_next_child(parent, NULL); child != NULL; \
635 child = __of_get_next_child(parent, child))
638 * of_get_next_child - Iterate a node childs
640 * @prev: previous child of the parent node, or NULL to get first
642 * Returns a node pointer with refcount incremented, use
643 * of_node_put() on it when done.
645 struct device_node
*of_get_next_child(const struct device_node
*node
,
646 struct device_node
*prev
)
648 struct device_node
*next
;
651 raw_spin_lock_irqsave(&devtree_lock
, flags
);
652 next
= __of_get_next_child(node
, prev
);
653 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
656 EXPORT_SYMBOL(of_get_next_child
);
659 * of_get_next_available_child - Find the next available child node
661 * @prev: previous child of the parent node, or NULL to get first
663 * This function is like of_get_next_child(), except that it
664 * automatically skips any disabled nodes (i.e. status = "disabled").
666 struct device_node
*of_get_next_available_child(const struct device_node
*node
,
667 struct device_node
*prev
)
669 struct device_node
*next
;
675 raw_spin_lock_irqsave(&devtree_lock
, flags
);
676 next
= prev
? prev
->sibling
: node
->child
;
677 for (; next
; next
= next
->sibling
) {
678 if (!__of_device_is_available(next
))
680 if (of_node_get(next
))
684 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
687 EXPORT_SYMBOL(of_get_next_available_child
);
690 * of_get_child_by_name - Find the child node by name for a given parent
692 * @name: child name to look for.
694 * This function looks for child node for given matching name
696 * Returns a node pointer if found, with refcount incremented, use
697 * of_node_put() on it when done.
698 * Returns NULL if node is not found.
700 struct device_node
*of_get_child_by_name(const struct device_node
*node
,
703 struct device_node
*child
;
705 for_each_child_of_node(node
, child
)
706 if (child
->name
&& (of_node_cmp(child
->name
, name
) == 0))
710 EXPORT_SYMBOL(of_get_child_by_name
);
712 static struct device_node
*__of_find_node_by_path(struct device_node
*parent
,
715 struct device_node
*child
;
716 int len
= strchrnul(path
, '/') - path
;
721 __for_each_child_of_node(parent
, child
) {
722 const char *name
= strrchr(child
->full_name
, '/');
723 if (WARN(!name
, "malformed device_node %s\n", child
->full_name
))
726 if (strncmp(path
, name
, len
) == 0 && (strlen(name
) == len
))
733 * of_find_node_by_path - Find a node matching a full OF path
734 * @path: Either the full path to match, or if the path does not
735 * start with '/', the name of a property of the /aliases
736 * node (an alias). In the case of an alias, the node
737 * matching the alias' value will be returned.
742 * foo/bar Valid alias + relative path
744 * Returns a node pointer with refcount incremented, use
745 * of_node_put() on it when done.
747 struct device_node
*of_find_node_by_path(const char *path
)
749 struct device_node
*np
= NULL
;
753 if (strcmp(path
, "/") == 0)
754 return of_node_get(of_root
);
756 /* The path could begin with an alias */
758 char *p
= strchrnul(path
, '/');
761 /* of_aliases must not be NULL */
765 for_each_property_of_node(of_aliases
, pp
) {
766 if (strlen(pp
->name
) == len
&& !strncmp(pp
->name
, path
, len
)) {
767 np
= of_find_node_by_path(pp
->value
);
776 /* Step down the tree matching path components */
777 raw_spin_lock_irqsave(&devtree_lock
, flags
);
779 np
= of_node_get(of_root
);
780 while (np
&& *path
== '/') {
781 path
++; /* Increment past '/' delimiter */
782 np
= __of_find_node_by_path(np
, path
);
783 path
= strchrnul(path
, '/');
785 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
788 EXPORT_SYMBOL(of_find_node_by_path
);
791 * of_find_node_by_name - Find a node by its "name" property
792 * @from: The node to start searching from or NULL, the node
793 * you pass will not be searched, only the next one
794 * will; typically, you pass what the previous call
795 * returned. of_node_put() will be called on it
796 * @name: The name string to match against
798 * Returns a node pointer with refcount incremented, use
799 * of_node_put() on it when done.
801 struct device_node
*of_find_node_by_name(struct device_node
*from
,
804 struct device_node
*np
;
807 raw_spin_lock_irqsave(&devtree_lock
, flags
);
808 for_each_of_allnodes_from(from
, np
)
809 if (np
->name
&& (of_node_cmp(np
->name
, name
) == 0)
813 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
816 EXPORT_SYMBOL(of_find_node_by_name
);
819 * of_find_node_by_type - Find a node by its "device_type" property
820 * @from: The node to start searching from, or NULL to start searching
821 * the entire device tree. The node you pass will not be
822 * searched, only the next one will; typically, you pass
823 * what the previous call returned. of_node_put() will be
824 * called on from for you.
825 * @type: The type string to match against
827 * Returns a node pointer with refcount incremented, use
828 * of_node_put() on it when done.
830 struct device_node
*of_find_node_by_type(struct device_node
*from
,
833 struct device_node
*np
;
836 raw_spin_lock_irqsave(&devtree_lock
, flags
);
837 for_each_of_allnodes_from(from
, np
)
838 if (np
->type
&& (of_node_cmp(np
->type
, type
) == 0)
842 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
845 EXPORT_SYMBOL(of_find_node_by_type
);
848 * of_find_compatible_node - Find a node based on type and one of the
849 * tokens in its "compatible" property
850 * @from: The node to start searching from or NULL, the node
851 * you pass will not be searched, only the next one
852 * will; typically, you pass what the previous call
853 * returned. of_node_put() will be called on it
854 * @type: The type string to match "device_type" or NULL to ignore
855 * @compatible: The string to match to one of the tokens in the device
858 * Returns a node pointer with refcount incremented, use
859 * of_node_put() on it when done.
861 struct device_node
*of_find_compatible_node(struct device_node
*from
,
862 const char *type
, const char *compatible
)
864 struct device_node
*np
;
867 raw_spin_lock_irqsave(&devtree_lock
, flags
);
868 for_each_of_allnodes_from(from
, np
)
869 if (__of_device_is_compatible(np
, compatible
, type
, NULL
) &&
873 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
876 EXPORT_SYMBOL(of_find_compatible_node
);
879 * of_find_node_with_property - Find a node which has a property with
881 * @from: The node to start searching from or NULL, the node
882 * you pass will not be searched, only the next one
883 * will; typically, you pass what the previous call
884 * returned. of_node_put() will be called on it
885 * @prop_name: The name of the property to look for.
887 * Returns a node pointer with refcount incremented, use
888 * of_node_put() on it when done.
890 struct device_node
*of_find_node_with_property(struct device_node
*from
,
891 const char *prop_name
)
893 struct device_node
*np
;
897 raw_spin_lock_irqsave(&devtree_lock
, flags
);
898 for_each_of_allnodes_from(from
, np
) {
899 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
900 if (of_prop_cmp(pp
->name
, prop_name
) == 0) {
908 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
911 EXPORT_SYMBOL(of_find_node_with_property
);
914 const struct of_device_id
*__of_match_node(const struct of_device_id
*matches
,
915 const struct device_node
*node
)
917 const struct of_device_id
*best_match
= NULL
;
918 int score
, best_score
= 0;
923 for (; matches
->name
[0] || matches
->type
[0] || matches
->compatible
[0]; matches
++) {
924 score
= __of_device_is_compatible(node
, matches
->compatible
,
925 matches
->type
, matches
->name
);
926 if (score
> best_score
) {
927 best_match
= matches
;
936 * of_match_node - Tell if an device_node has a matching of_match structure
937 * @matches: array of of device match structures to search in
938 * @node: the of device structure to match against
940 * Low level utility function used by device matching.
942 const struct of_device_id
*of_match_node(const struct of_device_id
*matches
,
943 const struct device_node
*node
)
945 const struct of_device_id
*match
;
948 raw_spin_lock_irqsave(&devtree_lock
, flags
);
949 match
= __of_match_node(matches
, node
);
950 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
953 EXPORT_SYMBOL(of_match_node
);
956 * of_find_matching_node_and_match - Find a node based on an of_device_id
958 * @from: The node to start searching from or NULL, the node
959 * you pass will not be searched, only the next one
960 * will; typically, you pass what the previous call
961 * returned. of_node_put() will be called on it
962 * @matches: array of of device match structures to search in
963 * @match Updated to point at the matches entry which matched
965 * Returns a node pointer with refcount incremented, use
966 * of_node_put() on it when done.
968 struct device_node
*of_find_matching_node_and_match(struct device_node
*from
,
969 const struct of_device_id
*matches
,
970 const struct of_device_id
**match
)
972 struct device_node
*np
;
973 const struct of_device_id
*m
;
979 raw_spin_lock_irqsave(&devtree_lock
, flags
);
980 for_each_of_allnodes_from(from
, np
) {
981 m
= __of_match_node(matches
, np
);
982 if (m
&& of_node_get(np
)) {
989 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
992 EXPORT_SYMBOL(of_find_matching_node_and_match
);
995 * of_modalias_node - Lookup appropriate modalias for a device node
996 * @node: pointer to a device tree node
997 * @modalias: Pointer to buffer that modalias value will be copied into
998 * @len: Length of modalias value
1000 * Based on the value of the compatible property, this routine will attempt
1001 * to choose an appropriate modalias value for a particular device tree node.
1002 * It does this by stripping the manufacturer prefix (as delimited by a ',')
1003 * from the first entry in the compatible list property.
1005 * This routine returns 0 on success, <0 on failure.
1007 int of_modalias_node(struct device_node
*node
, char *modalias
, int len
)
1009 const char *compatible
, *p
;
1012 compatible
= of_get_property(node
, "compatible", &cplen
);
1013 if (!compatible
|| strlen(compatible
) > cplen
)
1015 p
= strchr(compatible
, ',');
1016 strlcpy(modalias
, p
? p
+ 1 : compatible
, len
);
1019 EXPORT_SYMBOL_GPL(of_modalias_node
);
1022 * of_find_node_by_phandle - Find a node given a phandle
1023 * @handle: phandle of the node to find
1025 * Returns a node pointer with refcount incremented, use
1026 * of_node_put() on it when done.
1028 struct device_node
*of_find_node_by_phandle(phandle handle
)
1030 struct device_node
*np
;
1031 unsigned long flags
;
1036 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1037 for_each_of_allnodes(np
)
1038 if (np
->phandle
== handle
)
1041 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1044 EXPORT_SYMBOL(of_find_node_by_phandle
);
1047 * of_property_count_elems_of_size - Count the number of elements in a property
1049 * @np: device node from which the property value is to be read.
1050 * @propname: name of the property to be searched.
1051 * @elem_size: size of the individual element
1053 * Search for a property in a device node and count the number of elements of
1054 * size elem_size in it. Returns number of elements on sucess, -EINVAL if the
1055 * property does not exist or its length does not match a multiple of elem_size
1056 * and -ENODATA if the property does not have a value.
1058 int of_property_count_elems_of_size(const struct device_node
*np
,
1059 const char *propname
, int elem_size
)
1061 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1068 if (prop
->length
% elem_size
!= 0) {
1069 pr_err("size of %s in node %s is not a multiple of %d\n",
1070 propname
, np
->full_name
, elem_size
);
1074 return prop
->length
/ elem_size
;
1076 EXPORT_SYMBOL_GPL(of_property_count_elems_of_size
);
1079 * of_find_property_value_of_size
1081 * @np: device node from which the property value is to be read.
1082 * @propname: name of the property to be searched.
1083 * @len: requested length of property value
1085 * Search for a property in a device node and valid the requested size.
1086 * Returns the property value on success, -EINVAL if the property does not
1087 * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
1088 * property data isn't large enough.
1091 static void *of_find_property_value_of_size(const struct device_node
*np
,
1092 const char *propname
, u32 len
)
1094 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1097 return ERR_PTR(-EINVAL
);
1099 return ERR_PTR(-ENODATA
);
1100 if (len
> prop
->length
)
1101 return ERR_PTR(-EOVERFLOW
);
1107 * of_property_read_u32_index - Find and read a u32 from a multi-value property.
1109 * @np: device node from which the property value is to be read.
1110 * @propname: name of the property to be searched.
1111 * @index: index of the u32 in the list of values
1112 * @out_value: pointer to return value, modified only if no error.
1114 * Search for a property in a device node and read nth 32-bit value from
1115 * it. Returns 0 on success, -EINVAL if the property does not exist,
1116 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1117 * property data isn't large enough.
1119 * The out_value is modified only if a valid u32 value can be decoded.
1121 int of_property_read_u32_index(const struct device_node
*np
,
1122 const char *propname
,
1123 u32 index
, u32
*out_value
)
1125 const u32
*val
= of_find_property_value_of_size(np
, propname
,
1126 ((index
+ 1) * sizeof(*out_value
)));
1129 return PTR_ERR(val
);
1131 *out_value
= be32_to_cpup(((__be32
*)val
) + index
);
1134 EXPORT_SYMBOL_GPL(of_property_read_u32_index
);
1137 * of_property_read_u8_array - Find and read an array of u8 from a property.
1139 * @np: device node from which the property value is to be read.
1140 * @propname: name of the property to be searched.
1141 * @out_values: pointer to return value, modified only if return value is 0.
1142 * @sz: number of array elements to read
1144 * Search for a property in a device node and read 8-bit value(s) from
1145 * it. Returns 0 on success, -EINVAL if the property does not exist,
1146 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1147 * property data isn't large enough.
1149 * dts entry of array should be like:
1150 * property = /bits/ 8 <0x50 0x60 0x70>;
1152 * The out_values is modified only if a valid u8 value can be decoded.
1154 int of_property_read_u8_array(const struct device_node
*np
,
1155 const char *propname
, u8
*out_values
, size_t sz
)
1157 const u8
*val
= of_find_property_value_of_size(np
, propname
,
1158 (sz
* sizeof(*out_values
)));
1161 return PTR_ERR(val
);
1164 *out_values
++ = *val
++;
1167 EXPORT_SYMBOL_GPL(of_property_read_u8_array
);
1170 * of_property_read_u16_array - Find and read an array of u16 from a property.
1172 * @np: device node from which the property value is to be read.
1173 * @propname: name of the property to be searched.
1174 * @out_values: pointer to return value, modified only if return value is 0.
1175 * @sz: number of array elements to read
1177 * Search for a property in a device node and read 16-bit value(s) from
1178 * it. Returns 0 on success, -EINVAL if the property does not exist,
1179 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1180 * property data isn't large enough.
1182 * dts entry of array should be like:
1183 * property = /bits/ 16 <0x5000 0x6000 0x7000>;
1185 * The out_values is modified only if a valid u16 value can be decoded.
1187 int of_property_read_u16_array(const struct device_node
*np
,
1188 const char *propname
, u16
*out_values
, size_t sz
)
1190 const __be16
*val
= of_find_property_value_of_size(np
, propname
,
1191 (sz
* sizeof(*out_values
)));
1194 return PTR_ERR(val
);
1197 *out_values
++ = be16_to_cpup(val
++);
1200 EXPORT_SYMBOL_GPL(of_property_read_u16_array
);
1203 * of_property_read_u32_array - Find and read an array of 32 bit integers
1206 * @np: device node from which the property value is to be read.
1207 * @propname: name of the property to be searched.
1208 * @out_values: pointer to return value, modified only if return value is 0.
1209 * @sz: number of array elements to read
1211 * Search for a property in a device node and read 32-bit value(s) from
1212 * it. Returns 0 on success, -EINVAL if the property does not exist,
1213 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1214 * property data isn't large enough.
1216 * The out_values is modified only if a valid u32 value can be decoded.
1218 int of_property_read_u32_array(const struct device_node
*np
,
1219 const char *propname
, u32
*out_values
,
1222 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1223 (sz
* sizeof(*out_values
)));
1226 return PTR_ERR(val
);
1229 *out_values
++ = be32_to_cpup(val
++);
1232 EXPORT_SYMBOL_GPL(of_property_read_u32_array
);
1235 * of_property_read_u64 - Find and read a 64 bit integer from a property
1236 * @np: device node from which the property value is to be read.
1237 * @propname: name of the property to be searched.
1238 * @out_value: pointer to return value, modified only if return value is 0.
1240 * Search for a property in a device node and read a 64-bit value from
1241 * it. Returns 0 on success, -EINVAL if the property does not exist,
1242 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1243 * property data isn't large enough.
1245 * The out_value is modified only if a valid u64 value can be decoded.
1247 int of_property_read_u64(const struct device_node
*np
, const char *propname
,
1250 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1251 sizeof(*out_value
));
1254 return PTR_ERR(val
);
1256 *out_value
= of_read_number(val
, 2);
1259 EXPORT_SYMBOL_GPL(of_property_read_u64
);
1262 * of_property_read_string - Find and read a string from a property
1263 * @np: device node from which the property value is to be read.
1264 * @propname: name of the property to be searched.
1265 * @out_string: pointer to null terminated return string, modified only if
1266 * return value is 0.
1268 * Search for a property in a device tree node and retrieve a null
1269 * terminated string value (pointer to data, not a copy). Returns 0 on
1270 * success, -EINVAL if the property does not exist, -ENODATA if property
1271 * does not have a value, and -EILSEQ if the string is not null-terminated
1272 * within the length of the property data.
1274 * The out_string pointer is modified only if a valid string can be decoded.
1276 int of_property_read_string(struct device_node
*np
, const char *propname
,
1277 const char **out_string
)
1279 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1284 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1286 *out_string
= prop
->value
;
1289 EXPORT_SYMBOL_GPL(of_property_read_string
);
1292 * of_property_match_string() - Find string in a list and return index
1293 * @np: pointer to node containing string list property
1294 * @propname: string list property name
1295 * @string: pointer to string to search for in string list
1297 * This function searches a string list property and returns the index
1298 * of a specific string value.
1300 int of_property_match_string(struct device_node
*np
, const char *propname
,
1303 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1306 const char *p
, *end
;
1314 end
= p
+ prop
->length
;
1316 for (i
= 0; p
< end
; i
++, p
+= l
) {
1317 l
= strnlen(p
, end
- p
) + 1;
1320 pr_debug("comparing %s with %s\n", string
, p
);
1321 if (strcmp(string
, p
) == 0)
1322 return i
; /* Found it; return index */
1326 EXPORT_SYMBOL_GPL(of_property_match_string
);
1329 * of_property_read_string_util() - Utility helper for parsing string properties
1330 * @np: device node from which the property value is to be read.
1331 * @propname: name of the property to be searched.
1332 * @out_strs: output array of string pointers.
1333 * @sz: number of array elements to read.
1334 * @skip: Number of strings to skip over at beginning of list.
1336 * Don't call this function directly. It is a utility helper for the
1337 * of_property_read_string*() family of functions.
1339 int of_property_read_string_helper(struct device_node
*np
, const char *propname
,
1340 const char **out_strs
, size_t sz
, int skip
)
1342 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1344 const char *p
, *end
;
1351 end
= p
+ prop
->length
;
1353 for (i
= 0; p
< end
&& (!out_strs
|| i
< skip
+ sz
); i
++, p
+= l
) {
1354 l
= strnlen(p
, end
- p
) + 1;
1357 if (out_strs
&& i
>= skip
)
1361 return i
<= 0 ? -ENODATA
: i
;
1363 EXPORT_SYMBOL_GPL(of_property_read_string_helper
);
1365 void of_print_phandle_args(const char *msg
, const struct of_phandle_args
*args
)
1368 printk("%s %s", msg
, of_node_full_name(args
->np
));
1369 for (i
= 0; i
< args
->args_count
; i
++)
1370 printk(i
? ",%08x" : ":%08x", args
->args
[i
]);
1374 static int __of_parse_phandle_with_args(const struct device_node
*np
,
1375 const char *list_name
,
1376 const char *cells_name
,
1377 int cell_count
, int index
,
1378 struct of_phandle_args
*out_args
)
1380 const __be32
*list
, *list_end
;
1381 int rc
= 0, size
, cur_index
= 0;
1383 struct device_node
*node
= NULL
;
1386 /* Retrieve the phandle list property */
1387 list
= of_get_property(np
, list_name
, &size
);
1390 list_end
= list
+ size
/ sizeof(*list
);
1392 /* Loop over the phandles until all the requested entry is found */
1393 while (list
< list_end
) {
1398 * If phandle is 0, then it is an empty entry with no
1399 * arguments. Skip forward to the next entry.
1401 phandle
= be32_to_cpup(list
++);
1404 * Find the provider node and parse the #*-cells
1405 * property to determine the argument length.
1407 * This is not needed if the cell count is hard-coded
1408 * (i.e. cells_name not set, but cell_count is set),
1409 * except when we're going to return the found node
1412 if (cells_name
|| cur_index
== index
) {
1413 node
= of_find_node_by_phandle(phandle
);
1415 pr_err("%s: could not find phandle\n",
1422 if (of_property_read_u32(node
, cells_name
,
1424 pr_err("%s: could not get %s for %s\n",
1425 np
->full_name
, cells_name
,
1434 * Make sure that the arguments actually fit in the
1435 * remaining property data length
1437 if (list
+ count
> list_end
) {
1438 pr_err("%s: arguments longer than property\n",
1445 * All of the error cases above bail out of the loop, so at
1446 * this point, the parsing is successful. If the requested
1447 * index matches, then fill the out_args structure and return,
1448 * or return -ENOENT for an empty entry.
1451 if (cur_index
== index
) {
1457 if (WARN_ON(count
> MAX_PHANDLE_ARGS
))
1458 count
= MAX_PHANDLE_ARGS
;
1459 out_args
->np
= node
;
1460 out_args
->args_count
= count
;
1461 for (i
= 0; i
< count
; i
++)
1462 out_args
->args
[i
] = be32_to_cpup(list
++);
1467 /* Found it! return success */
1478 * Unlock node before returning result; will be one of:
1479 * -ENOENT : index is for empty phandle
1480 * -EINVAL : parsing error on data
1481 * [1..n] : Number of phandle (count mode; when index = -1)
1483 rc
= index
< 0 ? cur_index
: -ENOENT
;
1491 * of_parse_phandle - Resolve a phandle property to a device_node pointer
1492 * @np: Pointer to device node holding phandle property
1493 * @phandle_name: Name of property holding a phandle value
1494 * @index: For properties holding a table of phandles, this is the index into
1497 * Returns the device_node pointer with refcount incremented. Use
1498 * of_node_put() on it when done.
1500 struct device_node
*of_parse_phandle(const struct device_node
*np
,
1501 const char *phandle_name
, int index
)
1503 struct of_phandle_args args
;
1508 if (__of_parse_phandle_with_args(np
, phandle_name
, NULL
, 0,
1514 EXPORT_SYMBOL(of_parse_phandle
);
1517 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
1518 * @np: pointer to a device tree node containing a list
1519 * @list_name: property name that contains a list
1520 * @cells_name: property name that specifies phandles' arguments count
1521 * @index: index of a phandle to parse out
1522 * @out_args: optional pointer to output arguments structure (will be filled)
1524 * This function is useful to parse lists of phandles and their arguments.
1525 * Returns 0 on success and fills out_args, on error returns appropriate
1528 * Caller is responsible to call of_node_put() on the returned out_args->np
1534 * #list-cells = <2>;
1538 * #list-cells = <1>;
1542 * list = <&phandle1 1 2 &phandle2 3>;
1545 * To get a device_node of the `node2' node you may call this:
1546 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
1548 int of_parse_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1549 const char *cells_name
, int index
,
1550 struct of_phandle_args
*out_args
)
1554 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0,
1557 EXPORT_SYMBOL(of_parse_phandle_with_args
);
1560 * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
1561 * @np: pointer to a device tree node containing a list
1562 * @list_name: property name that contains a list
1563 * @cell_count: number of argument cells following the phandle
1564 * @index: index of a phandle to parse out
1565 * @out_args: optional pointer to output arguments structure (will be filled)
1567 * This function is useful to parse lists of phandles and their arguments.
1568 * Returns 0 on success and fills out_args, on error returns appropriate
1571 * Caller is responsible to call of_node_put() on the returned out_args->np
1583 * list = <&phandle1 0 2 &phandle2 2 3>;
1586 * To get a device_node of the `node2' node you may call this:
1587 * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
1589 int of_parse_phandle_with_fixed_args(const struct device_node
*np
,
1590 const char *list_name
, int cell_count
,
1591 int index
, struct of_phandle_args
*out_args
)
1595 return __of_parse_phandle_with_args(np
, list_name
, NULL
, cell_count
,
1598 EXPORT_SYMBOL(of_parse_phandle_with_fixed_args
);
1601 * of_count_phandle_with_args() - Find the number of phandles references in a property
1602 * @np: pointer to a device tree node containing a list
1603 * @list_name: property name that contains a list
1604 * @cells_name: property name that specifies phandles' arguments count
1606 * Returns the number of phandle + argument tuples within a property. It
1607 * is a typical pattern to encode a list of phandle and variable
1608 * arguments into a single property. The number of arguments is encoded
1609 * by a property in the phandle-target node. For example, a gpios
1610 * property would contain a list of GPIO specifies consisting of a
1611 * phandle and 1 or more arguments. The number of arguments are
1612 * determined by the #gpio-cells property in the node pointed to by the
1615 int of_count_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1616 const char *cells_name
)
1618 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0, -1,
1621 EXPORT_SYMBOL(of_count_phandle_with_args
);
1624 * __of_add_property - Add a property to a node without lock operations
1626 int __of_add_property(struct device_node
*np
, struct property
*prop
)
1628 struct property
**next
;
1631 next
= &np
->properties
;
1633 if (strcmp(prop
->name
, (*next
)->name
) == 0)
1634 /* duplicate ! don't insert it */
1637 next
= &(*next
)->next
;
1645 * of_add_property - Add a property to a node
1647 int of_add_property(struct device_node
*np
, struct property
*prop
)
1649 unsigned long flags
;
1652 mutex_lock(&of_mutex
);
1654 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1655 rc
= __of_add_property(np
, prop
);
1656 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1659 __of_add_property_sysfs(np
, prop
);
1661 mutex_unlock(&of_mutex
);
1664 of_property_notify(OF_RECONFIG_ADD_PROPERTY
, np
, prop
, NULL
);
1669 int __of_remove_property(struct device_node
*np
, struct property
*prop
)
1671 struct property
**next
;
1673 for (next
= &np
->properties
; *next
; next
= &(*next
)->next
) {
1680 /* found the node */
1682 prop
->next
= np
->deadprops
;
1683 np
->deadprops
= prop
;
1688 void __of_remove_property_sysfs(struct device_node
*np
, struct property
*prop
)
1690 if (!IS_ENABLED(CONFIG_SYSFS
))
1693 /* at early boot, bail here and defer setup to of_init() */
1694 if (of_kset
&& of_node_is_attached(np
))
1695 sysfs_remove_bin_file(&np
->kobj
, &prop
->attr
);
1699 * of_remove_property - Remove a property from a node.
1701 * Note that we don't actually remove it, since we have given out
1702 * who-knows-how-many pointers to the data using get-property.
1703 * Instead we just move the property to the "dead properties"
1704 * list, so it won't be found any more.
1706 int of_remove_property(struct device_node
*np
, struct property
*prop
)
1708 unsigned long flags
;
1711 mutex_lock(&of_mutex
);
1713 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1714 rc
= __of_remove_property(np
, prop
);
1715 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1718 __of_remove_property_sysfs(np
, prop
);
1720 mutex_unlock(&of_mutex
);
1723 of_property_notify(OF_RECONFIG_REMOVE_PROPERTY
, np
, prop
, NULL
);
1728 int __of_update_property(struct device_node
*np
, struct property
*newprop
,
1729 struct property
**oldpropp
)
1731 struct property
**next
, *oldprop
;
1733 for (next
= &np
->properties
; *next
; next
= &(*next
)->next
) {
1734 if (of_prop_cmp((*next
)->name
, newprop
->name
) == 0)
1737 *oldpropp
= oldprop
= *next
;
1740 /* replace the node */
1741 newprop
->next
= oldprop
->next
;
1743 oldprop
->next
= np
->deadprops
;
1744 np
->deadprops
= oldprop
;
1747 newprop
->next
= NULL
;
1754 void __of_update_property_sysfs(struct device_node
*np
, struct property
*newprop
,
1755 struct property
*oldprop
)
1757 if (!IS_ENABLED(CONFIG_SYSFS
))
1760 /* At early boot, bail out and defer setup to of_init() */
1765 sysfs_remove_bin_file(&np
->kobj
, &oldprop
->attr
);
1766 __of_add_property_sysfs(np
, newprop
);
1770 * of_update_property - Update a property in a node, if the property does
1771 * not exist, add it.
1773 * Note that we don't actually remove it, since we have given out
1774 * who-knows-how-many pointers to the data using get-property.
1775 * Instead we just move the property to the "dead properties" list,
1776 * and add the new property to the property list
1778 int of_update_property(struct device_node
*np
, struct property
*newprop
)
1780 struct property
*oldprop
;
1781 unsigned long flags
;
1787 mutex_lock(&of_mutex
);
1789 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1790 rc
= __of_update_property(np
, newprop
, &oldprop
);
1791 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1794 __of_update_property_sysfs(np
, newprop
, oldprop
);
1796 mutex_unlock(&of_mutex
);
1799 of_property_notify(OF_RECONFIG_UPDATE_PROPERTY
, np
, newprop
, oldprop
);
1804 static void of_alias_add(struct alias_prop
*ap
, struct device_node
*np
,
1805 int id
, const char *stem
, int stem_len
)
1809 strncpy(ap
->stem
, stem
, stem_len
);
1810 ap
->stem
[stem_len
] = 0;
1811 list_add_tail(&ap
->link
, &aliases_lookup
);
1812 pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
1813 ap
->alias
, ap
->stem
, ap
->id
, of_node_full_name(np
));
1817 * of_alias_scan - Scan all properties of 'aliases' node
1819 * The function scans all the properties of 'aliases' node and populate
1820 * the the global lookup table with the properties. It returns the
1821 * number of alias_prop found, or error code in error case.
1823 * @dt_alloc: An allocator that provides a virtual address to memory
1824 * for the resulting tree
1826 void of_alias_scan(void * (*dt_alloc
)(u64 size
, u64 align
))
1828 struct property
*pp
;
1830 of_aliases
= of_find_node_by_path("/aliases");
1831 of_chosen
= of_find_node_by_path("/chosen");
1832 if (of_chosen
== NULL
)
1833 of_chosen
= of_find_node_by_path("/chosen@0");
1836 /* linux,stdout-path and /aliases/stdout are for legacy compatibility */
1837 const char *name
= of_get_property(of_chosen
, "stdout-path", NULL
);
1839 name
= of_get_property(of_chosen
, "linux,stdout-path", NULL
);
1840 if (IS_ENABLED(CONFIG_PPC
) && !name
)
1841 name
= of_get_property(of_aliases
, "stdout", NULL
);
1843 of_stdout
= of_find_node_by_path(name
);
1849 for_each_property_of_node(of_aliases
, pp
) {
1850 const char *start
= pp
->name
;
1851 const char *end
= start
+ strlen(start
);
1852 struct device_node
*np
;
1853 struct alias_prop
*ap
;
1856 /* Skip those we do not want to proceed */
1857 if (!strcmp(pp
->name
, "name") ||
1858 !strcmp(pp
->name
, "phandle") ||
1859 !strcmp(pp
->name
, "linux,phandle"))
1862 np
= of_find_node_by_path(pp
->value
);
1866 /* walk the alias backwards to extract the id and work out
1867 * the 'stem' string */
1868 while (isdigit(*(end
-1)) && end
> start
)
1872 if (kstrtoint(end
, 10, &id
) < 0)
1875 /* Allocate an alias_prop with enough space for the stem */
1876 ap
= dt_alloc(sizeof(*ap
) + len
+ 1, 4);
1879 memset(ap
, 0, sizeof(*ap
) + len
+ 1);
1881 of_alias_add(ap
, np
, id
, start
, len
);
1886 * of_alias_get_id - Get alias id for the given device_node
1887 * @np: Pointer to the given device_node
1888 * @stem: Alias stem of the given device_node
1890 * The function travels the lookup table to get the alias id for the given
1891 * device_node and alias stem. It returns the alias id if found.
1893 int of_alias_get_id(struct device_node
*np
, const char *stem
)
1895 struct alias_prop
*app
;
1898 mutex_lock(&of_mutex
);
1899 list_for_each_entry(app
, &aliases_lookup
, link
) {
1900 if (strcmp(app
->stem
, stem
) != 0)
1903 if (np
== app
->np
) {
1908 mutex_unlock(&of_mutex
);
1912 EXPORT_SYMBOL_GPL(of_alias_get_id
);
1914 const __be32
*of_prop_next_u32(struct property
*prop
, const __be32
*cur
,
1917 const void *curv
= cur
;
1927 curv
+= sizeof(*cur
);
1928 if (curv
>= prop
->value
+ prop
->length
)
1932 *pu
= be32_to_cpup(curv
);
1935 EXPORT_SYMBOL_GPL(of_prop_next_u32
);
1937 const char *of_prop_next_string(struct property
*prop
, const char *cur
)
1939 const void *curv
= cur
;
1947 curv
+= strlen(cur
) + 1;
1948 if (curv
>= prop
->value
+ prop
->length
)
1953 EXPORT_SYMBOL_GPL(of_prop_next_string
);
1956 * of_console_check() - Test and setup console for DT setup
1957 * @dn - Pointer to device node
1958 * @name - Name to use for preferred console without index. ex. "ttyS"
1959 * @index - Index to use for preferred console.
1961 * Check if the given device node matches the stdout-path property in the
1962 * /chosen node. If it does then register it as the preferred console and return
1963 * TRUE. Otherwise return FALSE.
1965 bool of_console_check(struct device_node
*dn
, char *name
, int index
)
1967 if (!dn
|| dn
!= of_stdout
|| console_set_on_cmdline
)
1969 return !add_preferred_console(name
, index
, NULL
);
1971 EXPORT_SYMBOL_GPL(of_console_check
);
1974 * of_find_next_cache_node - Find a node's subsidiary cache
1975 * @np: node of type "cpu" or "cache"
1977 * Returns a node pointer with refcount incremented, use
1978 * of_node_put() on it when done. Caller should hold a reference
1981 struct device_node
*of_find_next_cache_node(const struct device_node
*np
)
1983 struct device_node
*child
;
1984 const phandle
*handle
;
1986 handle
= of_get_property(np
, "l2-cache", NULL
);
1988 handle
= of_get_property(np
, "next-level-cache", NULL
);
1991 return of_find_node_by_phandle(be32_to_cpup(handle
));
1993 /* OF on pmac has nodes instead of properties named "l2-cache"
1994 * beneath CPU nodes.
1996 if (!strcmp(np
->type
, "cpu"))
1997 for_each_child_of_node(np
, child
)
1998 if (!strcmp(child
->type
, "cache"))
2005 * of_graph_parse_endpoint() - parse common endpoint node properties
2006 * @node: pointer to endpoint device_node
2007 * @endpoint: pointer to the OF endpoint data structure
2009 * The caller should hold a reference to @node.
2011 int of_graph_parse_endpoint(const struct device_node
*node
,
2012 struct of_endpoint
*endpoint
)
2014 struct device_node
*port_node
= of_get_parent(node
);
2016 WARN_ONCE(!port_node
, "%s(): endpoint %s has no parent node\n",
2017 __func__
, node
->full_name
);
2019 memset(endpoint
, 0, sizeof(*endpoint
));
2021 endpoint
->local_node
= node
;
2023 * It doesn't matter whether the two calls below succeed.
2024 * If they don't then the default value 0 is used.
2026 of_property_read_u32(port_node
, "reg", &endpoint
->port
);
2027 of_property_read_u32(node
, "reg", &endpoint
->id
);
2029 of_node_put(port_node
);
2033 EXPORT_SYMBOL(of_graph_parse_endpoint
);
2036 * of_graph_get_next_endpoint() - get next endpoint node
2037 * @parent: pointer to the parent device node
2038 * @prev: previous endpoint node, or NULL to get first
2040 * Return: An 'endpoint' node pointer with refcount incremented. Refcount
2041 * of the passed @prev node is not decremented, the caller have to use
2042 * of_node_put() on it when done.
2044 struct device_node
*of_graph_get_next_endpoint(const struct device_node
*parent
,
2045 struct device_node
*prev
)
2047 struct device_node
*endpoint
;
2048 struct device_node
*port
;
2054 * Start by locating the port node. If no previous endpoint is specified
2055 * search for the first port node, otherwise get the previous endpoint
2059 struct device_node
*node
;
2061 node
= of_get_child_by_name(parent
, "ports");
2065 port
= of_get_child_by_name(parent
, "port");
2069 pr_err("%s(): no port node found in %s\n",
2070 __func__
, parent
->full_name
);
2074 port
= of_get_parent(prev
);
2075 if (WARN_ONCE(!port
, "%s(): endpoint %s has no parent node\n",
2076 __func__
, prev
->full_name
))
2080 * Avoid dropping prev node refcount to 0 when getting the next
2088 * Now that we have a port node, get the next endpoint by
2089 * getting the next child. If the previous endpoint is NULL this
2090 * will return the first child.
2092 endpoint
= of_get_next_child(port
, prev
);
2098 /* No more endpoints under this port, try the next one. */
2102 port
= of_get_next_child(parent
, port
);
2105 } while (of_node_cmp(port
->name
, "port"));
2108 EXPORT_SYMBOL(of_graph_get_next_endpoint
);
2111 * of_graph_get_remote_port_parent() - get remote port's parent node
2112 * @node: pointer to a local endpoint device_node
2114 * Return: Remote device node associated with remote endpoint node linked
2115 * to @node. Use of_node_put() on it when done.
2117 struct device_node
*of_graph_get_remote_port_parent(
2118 const struct device_node
*node
)
2120 struct device_node
*np
;
2123 /* Get remote endpoint node. */
2124 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2126 /* Walk 3 levels up only if there is 'ports' node. */
2127 for (depth
= 3; depth
&& np
; depth
--) {
2128 np
= of_get_next_parent(np
);
2129 if (depth
== 2 && of_node_cmp(np
->name
, "ports"))
2134 EXPORT_SYMBOL(of_graph_get_remote_port_parent
);
2137 * of_graph_get_remote_port() - get remote port node
2138 * @node: pointer to a local endpoint device_node
2140 * Return: Remote port node associated with remote endpoint node linked
2141 * to @node. Use of_node_put() on it when done.
2143 struct device_node
*of_graph_get_remote_port(const struct device_node
*node
)
2145 struct device_node
*np
;
2147 /* Get remote endpoint node. */
2148 np
= of_parse_phandle(node
, "remote-endpoint", 0);
2151 return of_get_next_parent(np
);
2153 EXPORT_SYMBOL(of_graph_get_remote_port
);