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.
21 #define pr_fmt(fmt) "OF: " fmt
23 #include <linux/console.h>
24 #include <linux/ctype.h>
25 #include <linux/cpu.h>
26 #include <linux/module.h>
28 #include <linux/of_device.h>
29 #include <linux/of_graph.h>
30 #include <linux/spinlock.h>
31 #include <linux/slab.h>
32 #include <linux/string.h>
33 #include <linux/proc_fs.h>
35 #include "of_private.h"
37 LIST_HEAD(aliases_lookup
);
39 struct device_node
*of_root
;
40 EXPORT_SYMBOL(of_root
);
41 struct device_node
*of_chosen
;
42 struct device_node
*of_aliases
;
43 struct device_node
*of_stdout
;
44 static const char *of_stdout_options
;
49 * Used to protect the of_aliases, to hold off addition of nodes to sysfs.
50 * This mutex must be held whenever modifications are being made to the
51 * device tree. The of_{attach,detach}_node() and
52 * of_{add,remove,update}_property() helpers make sure this happens.
54 DEFINE_MUTEX(of_mutex
);
56 /* use when traversing tree through the child, sibling,
57 * or parent members of struct device_node.
59 DEFINE_RAW_SPINLOCK(devtree_lock
);
61 int of_n_addr_cells(struct device_node
*np
)
68 ip
= of_get_property(np
, "#address-cells", NULL
);
70 return be32_to_cpup(ip
);
72 /* No #address-cells property for the root node */
73 return OF_ROOT_NODE_ADDR_CELLS_DEFAULT
;
75 EXPORT_SYMBOL(of_n_addr_cells
);
77 int of_n_size_cells(struct device_node
*np
)
84 ip
= of_get_property(np
, "#size-cells", NULL
);
86 return be32_to_cpup(ip
);
88 /* No #size-cells property for the root node */
89 return OF_ROOT_NODE_SIZE_CELLS_DEFAULT
;
91 EXPORT_SYMBOL(of_n_size_cells
);
94 int __weak
of_node_to_nid(struct device_node
*np
)
100 #ifndef CONFIG_OF_DYNAMIC
101 static void of_node_release(struct kobject
*kobj
)
103 /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
105 #endif /* CONFIG_OF_DYNAMIC */
107 struct kobj_type of_node_ktype
= {
108 .release
= of_node_release
,
111 static ssize_t
of_node_property_read(struct file
*filp
, struct kobject
*kobj
,
112 struct bin_attribute
*bin_attr
, char *buf
,
113 loff_t offset
, size_t count
)
115 struct property
*pp
= container_of(bin_attr
, struct property
, attr
);
116 return memory_read_from_buffer(buf
, count
, &offset
, pp
->value
, pp
->length
);
119 /* always return newly allocated name, caller must free after use */
120 static const char *safe_name(struct kobject
*kobj
, const char *orig_name
)
122 const char *name
= orig_name
;
123 struct kernfs_node
*kn
;
126 /* don't be a hero. After 16 tries give up */
127 while (i
< 16 && (kn
= sysfs_get_dirent(kobj
->sd
, name
))) {
129 if (name
!= orig_name
)
131 name
= kasprintf(GFP_KERNEL
, "%s#%i", orig_name
, ++i
);
134 if (name
== orig_name
) {
135 name
= kstrdup(orig_name
, GFP_KERNEL
);
137 pr_warn("Duplicate name in %s, renamed to \"%s\"\n",
138 kobject_name(kobj
), name
);
143 int __of_add_property_sysfs(struct device_node
*np
, struct property
*pp
)
147 /* Important: Don't leak passwords */
148 bool secure
= strncmp(pp
->name
, "security-", 9) == 0;
150 if (!IS_ENABLED(CONFIG_SYSFS
))
153 if (!of_kset
|| !of_node_is_attached(np
))
156 sysfs_bin_attr_init(&pp
->attr
);
157 pp
->attr
.attr
.name
= safe_name(&np
->kobj
, pp
->name
);
158 pp
->attr
.attr
.mode
= secure
? S_IRUSR
: S_IRUGO
;
159 pp
->attr
.size
= secure
? 0 : pp
->length
;
160 pp
->attr
.read
= of_node_property_read
;
162 rc
= sysfs_create_bin_file(&np
->kobj
, &pp
->attr
);
163 WARN(rc
, "error adding attribute %s to node %s\n", pp
->name
, np
->full_name
);
167 int __of_attach_node_sysfs(struct device_node
*np
)
170 struct kobject
*parent
;
174 if (!IS_ENABLED(CONFIG_SYSFS
))
180 np
->kobj
.kset
= of_kset
;
182 /* Nodes without parents are new top level trees */
183 name
= safe_name(&of_kset
->kobj
, "base");
186 name
= safe_name(&np
->parent
->kobj
, kbasename(np
->full_name
));
187 parent
= &np
->parent
->kobj
;
191 rc
= kobject_add(&np
->kobj
, parent
, "%s", name
);
196 for_each_property_of_node(np
, pp
)
197 __of_add_property_sysfs(np
, pp
);
202 void __init
of_core_init(void)
204 struct device_node
*np
;
206 /* Create the kset, and register existing nodes */
207 mutex_lock(&of_mutex
);
208 of_kset
= kset_create_and_add("devicetree", NULL
, firmware_kobj
);
210 mutex_unlock(&of_mutex
);
211 pr_err("failed to register existing nodes\n");
214 for_each_of_allnodes(np
)
215 __of_attach_node_sysfs(np
);
216 mutex_unlock(&of_mutex
);
218 /* Symlink in /proc as required by userspace ABI */
220 proc_symlink("device-tree", NULL
, "/sys/firmware/devicetree/base");
223 static struct property
*__of_find_property(const struct device_node
*np
,
224 const char *name
, int *lenp
)
231 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
232 if (of_prop_cmp(pp
->name
, name
) == 0) {
242 struct property
*of_find_property(const struct device_node
*np
,
249 raw_spin_lock_irqsave(&devtree_lock
, flags
);
250 pp
= __of_find_property(np
, name
, lenp
);
251 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
255 EXPORT_SYMBOL(of_find_property
);
257 struct device_node
*__of_find_all_nodes(struct device_node
*prev
)
259 struct device_node
*np
;
262 } else if (prev
->child
) {
265 /* Walk back up looking for a sibling, or the end of the structure */
267 while (np
->parent
&& !np
->sibling
)
269 np
= np
->sibling
; /* Might be null at the end of the tree */
275 * of_find_all_nodes - Get next node in global list
276 * @prev: Previous node or NULL to start iteration
277 * of_node_put() will be called on it
279 * Returns a node pointer with refcount incremented, use
280 * of_node_put() on it when done.
282 struct device_node
*of_find_all_nodes(struct device_node
*prev
)
284 struct device_node
*np
;
287 raw_spin_lock_irqsave(&devtree_lock
, flags
);
288 np
= __of_find_all_nodes(prev
);
291 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
294 EXPORT_SYMBOL(of_find_all_nodes
);
297 * Find a property with a given name for a given node
298 * and return the value.
300 const void *__of_get_property(const struct device_node
*np
,
301 const char *name
, int *lenp
)
303 struct property
*pp
= __of_find_property(np
, name
, lenp
);
305 return pp
? pp
->value
: NULL
;
309 * Find a property with a given name for a given node
310 * and return the value.
312 const void *of_get_property(const struct device_node
*np
, const char *name
,
315 struct property
*pp
= of_find_property(np
, name
, lenp
);
317 return pp
? pp
->value
: NULL
;
319 EXPORT_SYMBOL(of_get_property
);
322 * arch_match_cpu_phys_id - Match the given logical CPU and physical id
324 * @cpu: logical cpu index of a core/thread
325 * @phys_id: physical identifier of a core/thread
327 * CPU logical to physical index mapping is architecture specific.
328 * However this __weak function provides a default match of physical
329 * id to logical cpu index. phys_id provided here is usually values read
330 * from the device tree which must match the hardware internal registers.
332 * Returns true if the physical identifier and the logical cpu index
333 * correspond to the same core/thread, false otherwise.
335 bool __weak
arch_match_cpu_phys_id(int cpu
, u64 phys_id
)
337 return (u32
)phys_id
== cpu
;
341 * Checks if the given "prop_name" property holds the physical id of the
342 * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
343 * NULL, local thread number within the core is returned in it.
345 static bool __of_find_n_match_cpu_property(struct device_node
*cpun
,
346 const char *prop_name
, int cpu
, unsigned int *thread
)
349 int ac
, prop_len
, tid
;
352 ac
= of_n_addr_cells(cpun
);
353 cell
= of_get_property(cpun
, prop_name
, &prop_len
);
356 prop_len
/= sizeof(*cell
) * ac
;
357 for (tid
= 0; tid
< prop_len
; tid
++) {
358 hwid
= of_read_number(cell
, ac
);
359 if (arch_match_cpu_phys_id(cpu
, hwid
)) {
370 * arch_find_n_match_cpu_physical_id - See if the given device node is
371 * for the cpu corresponding to logical cpu 'cpu'. Return true if so,
372 * else false. If 'thread' is non-NULL, the local thread number within the
373 * core is returned in it.
375 bool __weak
arch_find_n_match_cpu_physical_id(struct device_node
*cpun
,
376 int cpu
, unsigned int *thread
)
378 /* Check for non-standard "ibm,ppc-interrupt-server#s" property
379 * for thread ids on PowerPC. If it doesn't exist fallback to
380 * standard "reg" property.
382 if (IS_ENABLED(CONFIG_PPC
) &&
383 __of_find_n_match_cpu_property(cpun
,
384 "ibm,ppc-interrupt-server#s",
388 return __of_find_n_match_cpu_property(cpun
, "reg", cpu
, thread
);
392 * of_get_cpu_node - Get device node associated with the given logical CPU
394 * @cpu: CPU number(logical index) for which device node is required
395 * @thread: if not NULL, local thread number within the physical core is
398 * The main purpose of this function is to retrieve the device node for the
399 * given logical CPU index. It should be used to initialize the of_node in
400 * cpu device. Once of_node in cpu device is populated, all the further
401 * references can use that instead.
403 * CPU logical to physical index mapping is architecture specific and is built
404 * before booting secondary cores. This function uses arch_match_cpu_phys_id
405 * which can be overridden by architecture specific implementation.
407 * Returns a node pointer for the logical cpu with refcount incremented, use
408 * of_node_put() on it when done. Returns NULL if not found.
410 struct device_node
*of_get_cpu_node(int cpu
, unsigned int *thread
)
412 struct device_node
*cpun
;
414 for_each_node_by_type(cpun
, "cpu") {
415 if (arch_find_n_match_cpu_physical_id(cpun
, cpu
, thread
))
420 EXPORT_SYMBOL(of_get_cpu_node
);
423 * __of_device_is_compatible() - Check if the node matches given constraints
424 * @device: pointer to node
425 * @compat: required compatible string, NULL or "" for any match
426 * @type: required device_type value, NULL or "" for any match
427 * @name: required node name, NULL or "" for any match
429 * Checks if the given @compat, @type and @name strings match the
430 * properties of the given @device. A constraints can be skipped by
431 * passing NULL or an empty string as the constraint.
433 * Returns 0 for no match, and a positive integer on match. The return
434 * value is a relative score with larger values indicating better
435 * matches. The score is weighted for the most specific compatible value
436 * to get the highest score. Matching type is next, followed by matching
437 * name. Practically speaking, this results in the following priority
440 * 1. specific compatible && type && name
441 * 2. specific compatible && type
442 * 3. specific compatible && name
443 * 4. specific compatible
444 * 5. general compatible && type && name
445 * 6. general compatible && type
446 * 7. general compatible && name
447 * 8. general compatible
452 static int __of_device_is_compatible(const struct device_node
*device
,
453 const char *compat
, const char *type
, const char *name
)
455 struct property
*prop
;
457 int index
= 0, score
= 0;
459 /* Compatible match has highest priority */
460 if (compat
&& compat
[0]) {
461 prop
= __of_find_property(device
, "compatible", NULL
);
462 for (cp
= of_prop_next_string(prop
, NULL
); cp
;
463 cp
= of_prop_next_string(prop
, cp
), index
++) {
464 if (of_compat_cmp(cp
, compat
, strlen(compat
)) == 0) {
465 score
= INT_MAX
/2 - (index
<< 2);
473 /* Matching type is better than matching name */
474 if (type
&& type
[0]) {
475 if (!device
->type
|| of_node_cmp(type
, device
->type
))
480 /* Matching name is a bit better than not */
481 if (name
&& name
[0]) {
482 if (!device
->name
|| of_node_cmp(name
, device
->name
))
490 /** Checks if the given "compat" string matches one of the strings in
491 * the device's "compatible" property
493 int of_device_is_compatible(const struct device_node
*device
,
499 raw_spin_lock_irqsave(&devtree_lock
, flags
);
500 res
= __of_device_is_compatible(device
, compat
, NULL
, NULL
);
501 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
504 EXPORT_SYMBOL(of_device_is_compatible
);
506 /** Checks if the device is compatible with any of the entries in
507 * a NULL terminated array of strings. Returns the best match
510 int of_device_compatible_match(struct device_node
*device
,
511 const char *const *compat
)
513 unsigned int tmp
, score
= 0;
519 tmp
= of_device_is_compatible(device
, *compat
);
529 * of_machine_is_compatible - Test root of device tree for a given compatible value
530 * @compat: compatible string to look for in root node's compatible property.
532 * Returns a positive integer if the root node has the given value in its
533 * compatible property.
535 int of_machine_is_compatible(const char *compat
)
537 struct device_node
*root
;
540 root
= of_find_node_by_path("/");
542 rc
= of_device_is_compatible(root
, compat
);
547 EXPORT_SYMBOL(of_machine_is_compatible
);
550 * __of_device_is_available - check if a device is available for use
552 * @device: Node to check for availability, with locks already held
554 * Returns true if the status property is absent or set to "okay" or "ok",
557 static bool __of_device_is_available(const struct device_node
*device
)
565 status
= __of_get_property(device
, "status", &statlen
);
570 if (!strcmp(status
, "okay") || !strcmp(status
, "ok"))
578 * of_device_is_available - check if a device is available for use
580 * @device: Node to check for availability
582 * Returns true if the status property is absent or set to "okay" or "ok",
585 bool of_device_is_available(const struct device_node
*device
)
590 raw_spin_lock_irqsave(&devtree_lock
, flags
);
591 res
= __of_device_is_available(device
);
592 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
596 EXPORT_SYMBOL(of_device_is_available
);
599 * of_device_is_big_endian - check if a device has BE registers
601 * @device: Node to check for endianness
603 * Returns true if the device has a "big-endian" property, or if the kernel
604 * was compiled for BE *and* the device has a "native-endian" property.
605 * Returns false otherwise.
607 * Callers would nominally use ioread32be/iowrite32be if
608 * of_device_is_big_endian() == true, or readl/writel otherwise.
610 bool of_device_is_big_endian(const struct device_node
*device
)
612 if (of_property_read_bool(device
, "big-endian"))
614 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN
) &&
615 of_property_read_bool(device
, "native-endian"))
619 EXPORT_SYMBOL(of_device_is_big_endian
);
622 * of_get_parent - Get a node's parent if any
623 * @node: Node to get parent
625 * Returns a node pointer with refcount incremented, use
626 * of_node_put() on it when done.
628 struct device_node
*of_get_parent(const struct device_node
*node
)
630 struct device_node
*np
;
636 raw_spin_lock_irqsave(&devtree_lock
, flags
);
637 np
= of_node_get(node
->parent
);
638 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
641 EXPORT_SYMBOL(of_get_parent
);
644 * of_get_next_parent - Iterate to a node's parent
645 * @node: Node to get parent of
647 * This is like of_get_parent() except that it drops the
648 * refcount on the passed node, making it suitable for iterating
649 * through a node's parents.
651 * Returns a node pointer with refcount incremented, use
652 * of_node_put() on it when done.
654 struct device_node
*of_get_next_parent(struct device_node
*node
)
656 struct device_node
*parent
;
662 raw_spin_lock_irqsave(&devtree_lock
, flags
);
663 parent
= of_node_get(node
->parent
);
665 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
668 EXPORT_SYMBOL(of_get_next_parent
);
670 static struct device_node
*__of_get_next_child(const struct device_node
*node
,
671 struct device_node
*prev
)
673 struct device_node
*next
;
678 next
= prev
? prev
->sibling
: node
->child
;
679 for (; next
; next
= next
->sibling
)
680 if (of_node_get(next
))
685 #define __for_each_child_of_node(parent, child) \
686 for (child = __of_get_next_child(parent, NULL); child != NULL; \
687 child = __of_get_next_child(parent, child))
690 * of_get_next_child - Iterate a node childs
692 * @prev: previous child of the parent node, or NULL to get first
694 * Returns a node pointer with refcount incremented, use of_node_put() on
695 * it when done. Returns NULL when prev is the last child. Decrements the
698 struct device_node
*of_get_next_child(const struct device_node
*node
,
699 struct device_node
*prev
)
701 struct device_node
*next
;
704 raw_spin_lock_irqsave(&devtree_lock
, flags
);
705 next
= __of_get_next_child(node
, prev
);
706 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
709 EXPORT_SYMBOL(of_get_next_child
);
712 * of_get_next_available_child - Find the next available child node
714 * @prev: previous child of the parent node, or NULL to get first
716 * This function is like of_get_next_child(), except that it
717 * automatically skips any disabled nodes (i.e. status = "disabled").
719 struct device_node
*of_get_next_available_child(const struct device_node
*node
,
720 struct device_node
*prev
)
722 struct device_node
*next
;
728 raw_spin_lock_irqsave(&devtree_lock
, flags
);
729 next
= prev
? prev
->sibling
: node
->child
;
730 for (; next
; next
= next
->sibling
) {
731 if (!__of_device_is_available(next
))
733 if (of_node_get(next
))
737 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
740 EXPORT_SYMBOL(of_get_next_available_child
);
743 * of_get_child_by_name - Find the child node by name for a given parent
745 * @name: child name to look for.
747 * This function looks for child node for given matching name
749 * Returns a node pointer if found, with refcount incremented, use
750 * of_node_put() on it when done.
751 * Returns NULL if node is not found.
753 struct device_node
*of_get_child_by_name(const struct device_node
*node
,
756 struct device_node
*child
;
758 for_each_child_of_node(node
, child
)
759 if (child
->name
&& (of_node_cmp(child
->name
, name
) == 0))
763 EXPORT_SYMBOL(of_get_child_by_name
);
765 static struct device_node
*__of_find_node_by_path(struct device_node
*parent
,
768 struct device_node
*child
;
771 len
= strcspn(path
, "/:");
775 __for_each_child_of_node(parent
, child
) {
776 const char *name
= strrchr(child
->full_name
, '/');
777 if (WARN(!name
, "malformed device_node %s\n", child
->full_name
))
780 if (strncmp(path
, name
, len
) == 0 && (strlen(name
) == len
))
787 * of_find_node_opts_by_path - Find a node matching a full OF path
788 * @path: Either the full path to match, or if the path does not
789 * start with '/', the name of a property of the /aliases
790 * node (an alias). In the case of an alias, the node
791 * matching the alias' value will be returned.
792 * @opts: Address of a pointer into which to store the start of
793 * an options string appended to the end of the path with
799 * foo/bar Valid alias + relative path
801 * Returns a node pointer with refcount incremented, use
802 * of_node_put() on it when done.
804 struct device_node
*of_find_node_opts_by_path(const char *path
, const char **opts
)
806 struct device_node
*np
= NULL
;
809 const char *separator
= strchr(path
, ':');
812 *opts
= separator
? separator
+ 1 : NULL
;
814 if (strcmp(path
, "/") == 0)
815 return of_node_get(of_root
);
817 /* The path could begin with an alias */
820 const char *p
= separator
;
823 p
= strchrnul(path
, '/');
826 /* of_aliases must not be NULL */
830 for_each_property_of_node(of_aliases
, pp
) {
831 if (strlen(pp
->name
) == len
&& !strncmp(pp
->name
, path
, len
)) {
832 np
= of_find_node_by_path(pp
->value
);
841 /* Step down the tree matching path components */
842 raw_spin_lock_irqsave(&devtree_lock
, flags
);
844 np
= of_node_get(of_root
);
845 while (np
&& *path
== '/') {
846 struct device_node
*tmp
= np
;
848 path
++; /* Increment past '/' delimiter */
849 np
= __of_find_node_by_path(np
, path
);
851 path
= strchrnul(path
, '/');
852 if (separator
&& separator
< path
)
855 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
858 EXPORT_SYMBOL(of_find_node_opts_by_path
);
861 * of_find_node_by_name - Find a node by its "name" property
862 * @from: The node to start searching from or NULL, the node
863 * you pass will not be searched, only the next one
864 * will; typically, you pass what the previous call
865 * returned. of_node_put() will be called on it
866 * @name: The name string to match against
868 * Returns a node pointer with refcount incremented, use
869 * of_node_put() on it when done.
871 struct device_node
*of_find_node_by_name(struct device_node
*from
,
874 struct device_node
*np
;
877 raw_spin_lock_irqsave(&devtree_lock
, flags
);
878 for_each_of_allnodes_from(from
, np
)
879 if (np
->name
&& (of_node_cmp(np
->name
, name
) == 0)
883 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
886 EXPORT_SYMBOL(of_find_node_by_name
);
889 * of_find_node_by_type - Find a node by its "device_type" property
890 * @from: The node to start searching from, or NULL to start searching
891 * the entire device tree. The node you pass will not be
892 * searched, only the next one will; typically, you pass
893 * what the previous call returned. of_node_put() will be
894 * called on from for you.
895 * @type: The type string to match against
897 * Returns a node pointer with refcount incremented, use
898 * of_node_put() on it when done.
900 struct device_node
*of_find_node_by_type(struct device_node
*from
,
903 struct device_node
*np
;
906 raw_spin_lock_irqsave(&devtree_lock
, flags
);
907 for_each_of_allnodes_from(from
, np
)
908 if (np
->type
&& (of_node_cmp(np
->type
, type
) == 0)
912 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
915 EXPORT_SYMBOL(of_find_node_by_type
);
918 * of_find_compatible_node - Find a node based on type and one of the
919 * tokens in its "compatible" property
920 * @from: The node to start searching from or NULL, the node
921 * you pass will not be searched, only the next one
922 * will; typically, you pass what the previous call
923 * returned. of_node_put() will be called on it
924 * @type: The type string to match "device_type" or NULL to ignore
925 * @compatible: The string to match to one of the tokens in the device
928 * Returns a node pointer with refcount incremented, use
929 * of_node_put() on it when done.
931 struct device_node
*of_find_compatible_node(struct device_node
*from
,
932 const char *type
, const char *compatible
)
934 struct device_node
*np
;
937 raw_spin_lock_irqsave(&devtree_lock
, flags
);
938 for_each_of_allnodes_from(from
, np
)
939 if (__of_device_is_compatible(np
, compatible
, type
, NULL
) &&
943 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
946 EXPORT_SYMBOL(of_find_compatible_node
);
949 * of_find_node_with_property - Find a node which has a property with
951 * @from: The node to start searching from or NULL, the node
952 * you pass will not be searched, only the next one
953 * will; typically, you pass what the previous call
954 * returned. of_node_put() will be called on it
955 * @prop_name: The name of the property to look for.
957 * Returns a node pointer with refcount incremented, use
958 * of_node_put() on it when done.
960 struct device_node
*of_find_node_with_property(struct device_node
*from
,
961 const char *prop_name
)
963 struct device_node
*np
;
967 raw_spin_lock_irqsave(&devtree_lock
, flags
);
968 for_each_of_allnodes_from(from
, np
) {
969 for (pp
= np
->properties
; pp
; pp
= pp
->next
) {
970 if (of_prop_cmp(pp
->name
, prop_name
) == 0) {
978 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
981 EXPORT_SYMBOL(of_find_node_with_property
);
984 const struct of_device_id
*__of_match_node(const struct of_device_id
*matches
,
985 const struct device_node
*node
)
987 const struct of_device_id
*best_match
= NULL
;
988 int score
, best_score
= 0;
993 for (; matches
->name
[0] || matches
->type
[0] || matches
->compatible
[0]; matches
++) {
994 score
= __of_device_is_compatible(node
, matches
->compatible
,
995 matches
->type
, matches
->name
);
996 if (score
> best_score
) {
997 best_match
= matches
;
1006 * of_match_node - Tell if a device_node has a matching of_match structure
1007 * @matches: array of of device match structures to search in
1008 * @node: the of device structure to match against
1010 * Low level utility function used by device matching.
1012 const struct of_device_id
*of_match_node(const struct of_device_id
*matches
,
1013 const struct device_node
*node
)
1015 const struct of_device_id
*match
;
1016 unsigned long flags
;
1018 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1019 match
= __of_match_node(matches
, node
);
1020 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1023 EXPORT_SYMBOL(of_match_node
);
1026 * of_find_matching_node_and_match - Find a node based on an of_device_id
1028 * @from: The node to start searching from or NULL, the node
1029 * you pass will not be searched, only the next one
1030 * will; typically, you pass what the previous call
1031 * returned. of_node_put() will be called on it
1032 * @matches: array of of device match structures to search in
1033 * @match Updated to point at the matches entry which matched
1035 * Returns a node pointer with refcount incremented, use
1036 * of_node_put() on it when done.
1038 struct device_node
*of_find_matching_node_and_match(struct device_node
*from
,
1039 const struct of_device_id
*matches
,
1040 const struct of_device_id
**match
)
1042 struct device_node
*np
;
1043 const struct of_device_id
*m
;
1044 unsigned long flags
;
1049 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1050 for_each_of_allnodes_from(from
, np
) {
1051 m
= __of_match_node(matches
, np
);
1052 if (m
&& of_node_get(np
)) {
1059 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1062 EXPORT_SYMBOL(of_find_matching_node_and_match
);
1065 * of_modalias_node - Lookup appropriate modalias for a device node
1066 * @node: pointer to a device tree node
1067 * @modalias: Pointer to buffer that modalias value will be copied into
1068 * @len: Length of modalias value
1070 * Based on the value of the compatible property, this routine will attempt
1071 * to choose an appropriate modalias value for a particular device tree node.
1072 * It does this by stripping the manufacturer prefix (as delimited by a ',')
1073 * from the first entry in the compatible list property.
1075 * This routine returns 0 on success, <0 on failure.
1077 int of_modalias_node(struct device_node
*node
, char *modalias
, int len
)
1079 const char *compatible
, *p
;
1082 compatible
= of_get_property(node
, "compatible", &cplen
);
1083 if (!compatible
|| strlen(compatible
) > cplen
)
1085 p
= strchr(compatible
, ',');
1086 strlcpy(modalias
, p
? p
+ 1 : compatible
, len
);
1089 EXPORT_SYMBOL_GPL(of_modalias_node
);
1092 * of_find_node_by_phandle - Find a node given a phandle
1093 * @handle: phandle of the node to find
1095 * Returns a node pointer with refcount incremented, use
1096 * of_node_put() on it when done.
1098 struct device_node
*of_find_node_by_phandle(phandle handle
)
1100 struct device_node
*np
;
1101 unsigned long flags
;
1106 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1107 for_each_of_allnodes(np
)
1108 if (np
->phandle
== handle
)
1111 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1114 EXPORT_SYMBOL(of_find_node_by_phandle
);
1117 * of_property_count_elems_of_size - Count the number of elements in a property
1119 * @np: device node from which the property value is to be read.
1120 * @propname: name of the property to be searched.
1121 * @elem_size: size of the individual element
1123 * Search for a property in a device node and count the number of elements of
1124 * size elem_size in it. Returns number of elements on sucess, -EINVAL if the
1125 * property does not exist or its length does not match a multiple of elem_size
1126 * and -ENODATA if the property does not have a value.
1128 int of_property_count_elems_of_size(const struct device_node
*np
,
1129 const char *propname
, int elem_size
)
1131 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1138 if (prop
->length
% elem_size
!= 0) {
1139 pr_err("size of %s in node %s is not a multiple of %d\n",
1140 propname
, np
->full_name
, elem_size
);
1144 return prop
->length
/ elem_size
;
1146 EXPORT_SYMBOL_GPL(of_property_count_elems_of_size
);
1149 * of_find_property_value_of_size
1151 * @np: device node from which the property value is to be read.
1152 * @propname: name of the property to be searched.
1153 * @min: minimum allowed length of property value
1154 * @max: maximum allowed length of property value (0 means unlimited)
1155 * @len: if !=NULL, actual length is written to here
1157 * Search for a property in a device node and valid the requested size.
1158 * Returns the property value on success, -EINVAL if the property does not
1159 * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
1160 * property data is too small or too large.
1163 static void *of_find_property_value_of_size(const struct device_node
*np
,
1164 const char *propname
, u32 min
, u32 max
, size_t *len
)
1166 struct property
*prop
= of_find_property(np
, propname
, NULL
);
1169 return ERR_PTR(-EINVAL
);
1171 return ERR_PTR(-ENODATA
);
1172 if (prop
->length
< min
)
1173 return ERR_PTR(-EOVERFLOW
);
1174 if (max
&& prop
->length
> max
)
1175 return ERR_PTR(-EOVERFLOW
);
1178 *len
= prop
->length
;
1184 * of_property_read_u32_index - Find and read a u32 from a multi-value property.
1186 * @np: device node from which the property value is to be read.
1187 * @propname: name of the property to be searched.
1188 * @index: index of the u32 in the list of values
1189 * @out_value: pointer to return value, modified only if no error.
1191 * Search for a property in a device node and read nth 32-bit value from
1192 * it. Returns 0 on success, -EINVAL if the property does not exist,
1193 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1194 * property data isn't large enough.
1196 * The out_value is modified only if a valid u32 value can be decoded.
1198 int of_property_read_u32_index(const struct device_node
*np
,
1199 const char *propname
,
1200 u32 index
, u32
*out_value
)
1202 const u32
*val
= of_find_property_value_of_size(np
, propname
,
1203 ((index
+ 1) * sizeof(*out_value
)),
1208 return PTR_ERR(val
);
1210 *out_value
= be32_to_cpup(((__be32
*)val
) + index
);
1213 EXPORT_SYMBOL_GPL(of_property_read_u32_index
);
1216 * of_property_read_u64_index - Find and read a u64 from a multi-value property.
1218 * @np: device node from which the property value is to be read.
1219 * @propname: name of the property to be searched.
1220 * @index: index of the u64 in the list of values
1221 * @out_value: pointer to return value, modified only if no error.
1223 * Search for a property in a device node and read nth 64-bit value from
1224 * it. Returns 0 on success, -EINVAL if the property does not exist,
1225 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1226 * property data isn't large enough.
1228 * The out_value is modified only if a valid u64 value can be decoded.
1230 int of_property_read_u64_index(const struct device_node
*np
,
1231 const char *propname
,
1232 u32 index
, u64
*out_value
)
1234 const u64
*val
= of_find_property_value_of_size(np
, propname
,
1235 ((index
+ 1) * sizeof(*out_value
)),
1239 return PTR_ERR(val
);
1241 *out_value
= be64_to_cpup(((__be64
*)val
) + index
);
1244 EXPORT_SYMBOL_GPL(of_property_read_u64_index
);
1247 * of_property_read_variable_u8_array - Find and read an array of u8 from a
1248 * property, with bounds on the minimum and maximum array size.
1250 * @np: device node from which the property value is to be read.
1251 * @propname: name of the property to be searched.
1252 * @out_values: pointer to return value, modified only if return value is 0.
1253 * @sz_min: minimum number of array elements to read
1254 * @sz_max: maximum number of array elements to read, if zero there is no
1255 * upper limit on the number of elements in the dts entry but only
1256 * sz_min will be read.
1258 * Search for a property in a device node and read 8-bit value(s) from
1259 * it. Returns number of elements read on success, -EINVAL if the property
1260 * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
1261 * if the property data is smaller than sz_min or longer than sz_max.
1263 * dts entry of array should be like:
1264 * property = /bits/ 8 <0x50 0x60 0x70>;
1266 * The out_values is modified only if a valid u8 value can be decoded.
1268 int of_property_read_variable_u8_array(const struct device_node
*np
,
1269 const char *propname
, u8
*out_values
,
1270 size_t sz_min
, size_t sz_max
)
1273 const u8
*val
= of_find_property_value_of_size(np
, propname
,
1274 (sz_min
* sizeof(*out_values
)),
1275 (sz_max
* sizeof(*out_values
)),
1279 return PTR_ERR(val
);
1284 sz
/= sizeof(*out_values
);
1288 *out_values
++ = *val
++;
1292 EXPORT_SYMBOL_GPL(of_property_read_variable_u8_array
);
1295 * of_property_read_variable_u16_array - Find and read an array of u16 from a
1296 * property, with bounds on the minimum and maximum array size.
1298 * @np: device node from which the property value is to be read.
1299 * @propname: name of the property to be searched.
1300 * @out_values: pointer to return value, modified only if return value is 0.
1301 * @sz_min: minimum number of array elements to read
1302 * @sz_max: maximum number of array elements to read, if zero there is no
1303 * upper limit on the number of elements in the dts entry but only
1304 * sz_min will be read.
1306 * Search for a property in a device node and read 16-bit value(s) from
1307 * it. Returns number of elements read on success, -EINVAL if the property
1308 * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
1309 * if the property data is smaller than sz_min or longer than sz_max.
1311 * dts entry of array should be like:
1312 * property = /bits/ 16 <0x5000 0x6000 0x7000>;
1314 * The out_values is modified only if a valid u16 value can be decoded.
1316 int of_property_read_variable_u16_array(const struct device_node
*np
,
1317 const char *propname
, u16
*out_values
,
1318 size_t sz_min
, size_t sz_max
)
1321 const __be16
*val
= of_find_property_value_of_size(np
, propname
,
1322 (sz_min
* sizeof(*out_values
)),
1323 (sz_max
* sizeof(*out_values
)),
1327 return PTR_ERR(val
);
1332 sz
/= sizeof(*out_values
);
1336 *out_values
++ = be16_to_cpup(val
++);
1340 EXPORT_SYMBOL_GPL(of_property_read_variable_u16_array
);
1343 * of_property_read_variable_u32_array - Find and read an array of 32 bit
1344 * integers from a property, with bounds on the minimum and maximum array size.
1346 * @np: device node from which the property value is to be read.
1347 * @propname: name of the property to be searched.
1348 * @out_values: pointer to return value, modified only if return value is 0.
1349 * @sz_min: minimum number of array elements to read
1350 * @sz_max: maximum number of array elements to read, if zero there is no
1351 * upper limit on the number of elements in the dts entry but only
1352 * sz_min will be read.
1354 * Search for a property in a device node and read 32-bit value(s) from
1355 * it. Returns number of elements read on success, -EINVAL if the property
1356 * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
1357 * if the property data is smaller than sz_min or longer than sz_max.
1359 * The out_values is modified only if a valid u32 value can be decoded.
1361 int of_property_read_variable_u32_array(const struct device_node
*np
,
1362 const char *propname
, u32
*out_values
,
1363 size_t sz_min
, size_t sz_max
)
1366 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1367 (sz_min
* sizeof(*out_values
)),
1368 (sz_max
* sizeof(*out_values
)),
1372 return PTR_ERR(val
);
1377 sz
/= sizeof(*out_values
);
1381 *out_values
++ = be32_to_cpup(val
++);
1385 EXPORT_SYMBOL_GPL(of_property_read_variable_u32_array
);
1388 * of_property_read_u64 - Find and read a 64 bit integer from a property
1389 * @np: device node from which the property value is to be read.
1390 * @propname: name of the property to be searched.
1391 * @out_value: pointer to return value, modified only if return value is 0.
1393 * Search for a property in a device node and read a 64-bit value from
1394 * it. Returns 0 on success, -EINVAL if the property does not exist,
1395 * -ENODATA if property does not have a value, and -EOVERFLOW if the
1396 * property data isn't large enough.
1398 * The out_value is modified only if a valid u64 value can be decoded.
1400 int of_property_read_u64(const struct device_node
*np
, const char *propname
,
1403 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1409 return PTR_ERR(val
);
1411 *out_value
= of_read_number(val
, 2);
1414 EXPORT_SYMBOL_GPL(of_property_read_u64
);
1417 * of_property_read_variable_u64_array - Find and read an array of 64 bit
1418 * integers from a property, with bounds on the minimum and maximum array size.
1420 * @np: device node from which the property value is to be read.
1421 * @propname: name of the property to be searched.
1422 * @out_values: pointer to return value, modified only if return value is 0.
1423 * @sz_min: minimum number of array elements to read
1424 * @sz_max: maximum number of array elements to read, if zero there is no
1425 * upper limit on the number of elements in the dts entry but only
1426 * sz_min will be read.
1428 * Search for a property in a device node and read 64-bit value(s) from
1429 * it. Returns number of elements read on success, -EINVAL if the property
1430 * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
1431 * if the property data is smaller than sz_min or longer than sz_max.
1433 * The out_values is modified only if a valid u64 value can be decoded.
1435 int of_property_read_variable_u64_array(const struct device_node
*np
,
1436 const char *propname
, u64
*out_values
,
1437 size_t sz_min
, size_t sz_max
)
1440 const __be32
*val
= of_find_property_value_of_size(np
, propname
,
1441 (sz_min
* sizeof(*out_values
)),
1442 (sz_max
* sizeof(*out_values
)),
1446 return PTR_ERR(val
);
1451 sz
/= sizeof(*out_values
);
1455 *out_values
++ = of_read_number(val
, 2);
1461 EXPORT_SYMBOL_GPL(of_property_read_variable_u64_array
);
1464 * of_property_read_string - Find and read a string from a property
1465 * @np: device node from which the property value is to be read.
1466 * @propname: name of the property to be searched.
1467 * @out_string: pointer to null terminated return string, modified only if
1468 * return value is 0.
1470 * Search for a property in a device tree node and retrieve a null
1471 * terminated string value (pointer to data, not a copy). Returns 0 on
1472 * success, -EINVAL if the property does not exist, -ENODATA if property
1473 * does not have a value, and -EILSEQ if the string is not null-terminated
1474 * within the length of the property data.
1476 * The out_string pointer is modified only if a valid string can be decoded.
1478 int of_property_read_string(const struct device_node
*np
, const char *propname
,
1479 const char **out_string
)
1481 const struct property
*prop
= of_find_property(np
, propname
, NULL
);
1486 if (strnlen(prop
->value
, prop
->length
) >= prop
->length
)
1488 *out_string
= prop
->value
;
1491 EXPORT_SYMBOL_GPL(of_property_read_string
);
1494 * of_property_match_string() - Find string in a list and return index
1495 * @np: pointer to node containing string list property
1496 * @propname: string list property name
1497 * @string: pointer to string to search for in string list
1499 * This function searches a string list property and returns the index
1500 * of a specific string value.
1502 int of_property_match_string(const struct device_node
*np
, const char *propname
,
1505 const struct property
*prop
= of_find_property(np
, propname
, NULL
);
1508 const char *p
, *end
;
1516 end
= p
+ prop
->length
;
1518 for (i
= 0; p
< end
; i
++, p
+= l
) {
1519 l
= strnlen(p
, end
- p
) + 1;
1522 pr_debug("comparing %s with %s\n", string
, p
);
1523 if (strcmp(string
, p
) == 0)
1524 return i
; /* Found it; return index */
1528 EXPORT_SYMBOL_GPL(of_property_match_string
);
1531 * of_property_read_string_helper() - Utility helper for parsing string properties
1532 * @np: device node from which the property value is to be read.
1533 * @propname: name of the property to be searched.
1534 * @out_strs: output array of string pointers.
1535 * @sz: number of array elements to read.
1536 * @skip: Number of strings to skip over at beginning of list.
1538 * Don't call this function directly. It is a utility helper for the
1539 * of_property_read_string*() family of functions.
1541 int of_property_read_string_helper(const struct device_node
*np
,
1542 const char *propname
, const char **out_strs
,
1543 size_t sz
, int skip
)
1545 const struct property
*prop
= of_find_property(np
, propname
, NULL
);
1547 const char *p
, *end
;
1554 end
= p
+ prop
->length
;
1556 for (i
= 0; p
< end
&& (!out_strs
|| i
< skip
+ sz
); i
++, p
+= l
) {
1557 l
= strnlen(p
, end
- p
) + 1;
1560 if (out_strs
&& i
>= skip
)
1564 return i
<= 0 ? -ENODATA
: i
;
1566 EXPORT_SYMBOL_GPL(of_property_read_string_helper
);
1568 void of_print_phandle_args(const char *msg
, const struct of_phandle_args
*args
)
1571 printk("%s %s", msg
, of_node_full_name(args
->np
));
1572 for (i
= 0; i
< args
->args_count
; i
++) {
1573 const char delim
= i
? ',' : ':';
1575 pr_cont("%c%08x", delim
, args
->args
[i
]);
1580 int of_phandle_iterator_init(struct of_phandle_iterator
*it
,
1581 const struct device_node
*np
,
1582 const char *list_name
,
1583 const char *cells_name
,
1589 memset(it
, 0, sizeof(*it
));
1591 list
= of_get_property(np
, list_name
, &size
);
1595 it
->cells_name
= cells_name
;
1596 it
->cell_count
= cell_count
;
1598 it
->list_end
= list
+ size
/ sizeof(*list
);
1599 it
->phandle_end
= list
;
1604 EXPORT_SYMBOL_GPL(of_phandle_iterator_init
);
1606 int of_phandle_iterator_next(struct of_phandle_iterator
*it
)
1611 of_node_put(it
->node
);
1615 if (!it
->cur
|| it
->phandle_end
>= it
->list_end
)
1618 it
->cur
= it
->phandle_end
;
1620 /* If phandle is 0, then it is an empty entry with no arguments. */
1621 it
->phandle
= be32_to_cpup(it
->cur
++);
1626 * Find the provider node and parse the #*-cells property to
1627 * determine the argument length.
1629 it
->node
= of_find_node_by_phandle(it
->phandle
);
1631 if (it
->cells_name
) {
1633 pr_err("%s: could not find phandle\n",
1634 it
->parent
->full_name
);
1638 if (of_property_read_u32(it
->node
, it
->cells_name
,
1640 pr_err("%s: could not get %s for %s\n",
1641 it
->parent
->full_name
,
1643 it
->node
->full_name
);
1647 count
= it
->cell_count
;
1651 * Make sure that the arguments actually fit in the remaining
1652 * property data length
1654 if (it
->cur
+ count
> it
->list_end
) {
1655 pr_err("%s: arguments longer than property\n",
1656 it
->parent
->full_name
);
1661 it
->phandle_end
= it
->cur
+ count
;
1662 it
->cur_count
= count
;
1668 of_node_put(it
->node
);
1674 EXPORT_SYMBOL_GPL(of_phandle_iterator_next
);
1676 int of_phandle_iterator_args(struct of_phandle_iterator
*it
,
1682 count
= it
->cur_count
;
1684 if (WARN_ON(size
< count
))
1687 for (i
= 0; i
< count
; i
++)
1688 args
[i
] = be32_to_cpup(it
->cur
++);
1693 static int __of_parse_phandle_with_args(const struct device_node
*np
,
1694 const char *list_name
,
1695 const char *cells_name
,
1696 int cell_count
, int index
,
1697 struct of_phandle_args
*out_args
)
1699 struct of_phandle_iterator it
;
1700 int rc
, cur_index
= 0;
1702 /* Loop over the phandles until all the requested entry is found */
1703 of_for_each_phandle(&it
, rc
, np
, list_name
, cells_name
, cell_count
) {
1705 * All of the error cases bail out of the loop, so at
1706 * this point, the parsing is successful. If the requested
1707 * index matches, then fill the out_args structure and return,
1708 * or return -ENOENT for an empty entry.
1711 if (cur_index
== index
) {
1718 c
= of_phandle_iterator_args(&it
,
1721 out_args
->np
= it
.node
;
1722 out_args
->args_count
= c
;
1724 of_node_put(it
.node
);
1727 /* Found it! return success */
1735 * Unlock node before returning result; will be one of:
1736 * -ENOENT : index is for empty phandle
1737 * -EINVAL : parsing error on data
1741 of_node_put(it
.node
);
1746 * of_parse_phandle - Resolve a phandle property to a device_node pointer
1747 * @np: Pointer to device node holding phandle property
1748 * @phandle_name: Name of property holding a phandle value
1749 * @index: For properties holding a table of phandles, this is the index into
1752 * Returns the device_node pointer with refcount incremented. Use
1753 * of_node_put() on it when done.
1755 struct device_node
*of_parse_phandle(const struct device_node
*np
,
1756 const char *phandle_name
, int index
)
1758 struct of_phandle_args args
;
1763 if (__of_parse_phandle_with_args(np
, phandle_name
, NULL
, 0,
1769 EXPORT_SYMBOL(of_parse_phandle
);
1772 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
1773 * @np: pointer to a device tree node containing a list
1774 * @list_name: property name that contains a list
1775 * @cells_name: property name that specifies phandles' arguments count
1776 * @index: index of a phandle to parse out
1777 * @out_args: optional pointer to output arguments structure (will be filled)
1779 * This function is useful to parse lists of phandles and their arguments.
1780 * Returns 0 on success and fills out_args, on error returns appropriate
1783 * Caller is responsible to call of_node_put() on the returned out_args->np
1789 * #list-cells = <2>;
1793 * #list-cells = <1>;
1797 * list = <&phandle1 1 2 &phandle2 3>;
1800 * To get a device_node of the `node2' node you may call this:
1801 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
1803 int of_parse_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1804 const char *cells_name
, int index
,
1805 struct of_phandle_args
*out_args
)
1809 return __of_parse_phandle_with_args(np
, list_name
, cells_name
, 0,
1812 EXPORT_SYMBOL(of_parse_phandle_with_args
);
1815 * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
1816 * @np: pointer to a device tree node containing a list
1817 * @list_name: property name that contains a list
1818 * @cell_count: number of argument cells following the phandle
1819 * @index: index of a phandle to parse out
1820 * @out_args: optional pointer to output arguments structure (will be filled)
1822 * This function is useful to parse lists of phandles and their arguments.
1823 * Returns 0 on success and fills out_args, on error returns appropriate
1826 * Caller is responsible to call of_node_put() on the returned out_args->np
1838 * list = <&phandle1 0 2 &phandle2 2 3>;
1841 * To get a device_node of the `node2' node you may call this:
1842 * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
1844 int of_parse_phandle_with_fixed_args(const struct device_node
*np
,
1845 const char *list_name
, int cell_count
,
1846 int index
, struct of_phandle_args
*out_args
)
1850 return __of_parse_phandle_with_args(np
, list_name
, NULL
, cell_count
,
1853 EXPORT_SYMBOL(of_parse_phandle_with_fixed_args
);
1856 * of_count_phandle_with_args() - Find the number of phandles references in a property
1857 * @np: pointer to a device tree node containing a list
1858 * @list_name: property name that contains a list
1859 * @cells_name: property name that specifies phandles' arguments count
1861 * Returns the number of phandle + argument tuples within a property. It
1862 * is a typical pattern to encode a list of phandle and variable
1863 * arguments into a single property. The number of arguments is encoded
1864 * by a property in the phandle-target node. For example, a gpios
1865 * property would contain a list of GPIO specifies consisting of a
1866 * phandle and 1 or more arguments. The number of arguments are
1867 * determined by the #gpio-cells property in the node pointed to by the
1870 int of_count_phandle_with_args(const struct device_node
*np
, const char *list_name
,
1871 const char *cells_name
)
1873 struct of_phandle_iterator it
;
1874 int rc
, cur_index
= 0;
1876 rc
= of_phandle_iterator_init(&it
, np
, list_name
, cells_name
, 0);
1880 while ((rc
= of_phandle_iterator_next(&it
)) == 0)
1888 EXPORT_SYMBOL(of_count_phandle_with_args
);
1891 * __of_add_property - Add a property to a node without lock operations
1893 int __of_add_property(struct device_node
*np
, struct property
*prop
)
1895 struct property
**next
;
1898 next
= &np
->properties
;
1900 if (strcmp(prop
->name
, (*next
)->name
) == 0)
1901 /* duplicate ! don't insert it */
1904 next
= &(*next
)->next
;
1912 * of_add_property - Add a property to a node
1914 int of_add_property(struct device_node
*np
, struct property
*prop
)
1916 unsigned long flags
;
1919 mutex_lock(&of_mutex
);
1921 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1922 rc
= __of_add_property(np
, prop
);
1923 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1926 __of_add_property_sysfs(np
, prop
);
1928 mutex_unlock(&of_mutex
);
1931 of_property_notify(OF_RECONFIG_ADD_PROPERTY
, np
, prop
, NULL
);
1936 int __of_remove_property(struct device_node
*np
, struct property
*prop
)
1938 struct property
**next
;
1940 for (next
= &np
->properties
; *next
; next
= &(*next
)->next
) {
1947 /* found the node */
1949 prop
->next
= np
->deadprops
;
1950 np
->deadprops
= prop
;
1955 void __of_sysfs_remove_bin_file(struct device_node
*np
, struct property
*prop
)
1957 sysfs_remove_bin_file(&np
->kobj
, &prop
->attr
);
1958 kfree(prop
->attr
.attr
.name
);
1961 void __of_remove_property_sysfs(struct device_node
*np
, struct property
*prop
)
1963 if (!IS_ENABLED(CONFIG_SYSFS
))
1966 /* at early boot, bail here and defer setup to of_init() */
1967 if (of_kset
&& of_node_is_attached(np
))
1968 __of_sysfs_remove_bin_file(np
, prop
);
1972 * of_remove_property - Remove a property from a node.
1974 * Note that we don't actually remove it, since we have given out
1975 * who-knows-how-many pointers to the data using get-property.
1976 * Instead we just move the property to the "dead properties"
1977 * list, so it won't be found any more.
1979 int of_remove_property(struct device_node
*np
, struct property
*prop
)
1981 unsigned long flags
;
1987 mutex_lock(&of_mutex
);
1989 raw_spin_lock_irqsave(&devtree_lock
, flags
);
1990 rc
= __of_remove_property(np
, prop
);
1991 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
1994 __of_remove_property_sysfs(np
, prop
);
1996 mutex_unlock(&of_mutex
);
1999 of_property_notify(OF_RECONFIG_REMOVE_PROPERTY
, np
, prop
, NULL
);
2004 int __of_update_property(struct device_node
*np
, struct property
*newprop
,
2005 struct property
**oldpropp
)
2007 struct property
**next
, *oldprop
;
2009 for (next
= &np
->properties
; *next
; next
= &(*next
)->next
) {
2010 if (of_prop_cmp((*next
)->name
, newprop
->name
) == 0)
2013 *oldpropp
= oldprop
= *next
;
2016 /* replace the node */
2017 newprop
->next
= oldprop
->next
;
2019 oldprop
->next
= np
->deadprops
;
2020 np
->deadprops
= oldprop
;
2023 newprop
->next
= NULL
;
2030 void __of_update_property_sysfs(struct device_node
*np
, struct property
*newprop
,
2031 struct property
*oldprop
)
2033 if (!IS_ENABLED(CONFIG_SYSFS
))
2036 /* At early boot, bail out and defer setup to of_init() */
2041 __of_sysfs_remove_bin_file(np
, oldprop
);
2042 __of_add_property_sysfs(np
, newprop
);
2046 * of_update_property - Update a property in a node, if the property does
2047 * not exist, add it.
2049 * Note that we don't actually remove it, since we have given out
2050 * who-knows-how-many pointers to the data using get-property.
2051 * Instead we just move the property to the "dead properties" list,
2052 * and add the new property to the property list
2054 int of_update_property(struct device_node
*np
, struct property
*newprop
)
2056 struct property
*oldprop
;
2057 unsigned long flags
;
2063 mutex_lock(&of_mutex
);
2065 raw_spin_lock_irqsave(&devtree_lock
, flags
);
2066 rc
= __of_update_property(np
, newprop
, &oldprop
);
2067 raw_spin_unlock_irqrestore(&devtree_lock
, flags
);
2070 __of_update_property_sysfs(np
, newprop
, oldprop
);
2072 mutex_unlock(&of_mutex
);
2075 of_property_notify(OF_RECONFIG_UPDATE_PROPERTY
, np
, newprop
, oldprop
);
2080 static void of_alias_add(struct alias_prop
*ap
, struct device_node
*np
,
2081 int id
, const char *stem
, int stem_len
)
2085 strncpy(ap
->stem
, stem
, stem_len
);
2086 ap
->stem
[stem_len
] = 0;
2087 list_add_tail(&ap
->link
, &aliases_lookup
);
2088 pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
2089 ap
->alias
, ap
->stem
, ap
->id
, of_node_full_name(np
));
2093 * of_alias_scan - Scan all properties of the 'aliases' node
2095 * The function scans all the properties of the 'aliases' node and populates
2096 * the global lookup table with the properties. It returns the
2097 * number of alias properties found, or an error code in case of failure.
2099 * @dt_alloc: An allocator that provides a virtual address to memory
2100 * for storing the resulting tree
2102 void of_alias_scan(void * (*dt_alloc
)(u64 size
, u64 align
))
2104 struct property
*pp
;
2106 of_aliases
= of_find_node_by_path("/aliases");
2107 of_chosen
= of_find_node_by_path("/chosen");
2108 if (of_chosen
== NULL
)
2109 of_chosen
= of_find_node_by_path("/chosen@0");
2112 /* linux,stdout-path and /aliases/stdout are for legacy compatibility */
2113 const char *name
= of_get_property(of_chosen
, "stdout-path", NULL
);
2115 name
= of_get_property(of_chosen
, "linux,stdout-path", NULL
);
2116 if (IS_ENABLED(CONFIG_PPC
) && !name
)
2117 name
= of_get_property(of_aliases
, "stdout", NULL
);
2119 of_stdout
= of_find_node_opts_by_path(name
, &of_stdout_options
);
2125 for_each_property_of_node(of_aliases
, pp
) {
2126 const char *start
= pp
->name
;
2127 const char *end
= start
+ strlen(start
);
2128 struct device_node
*np
;
2129 struct alias_prop
*ap
;
2132 /* Skip those we do not want to proceed */
2133 if (!strcmp(pp
->name
, "name") ||
2134 !strcmp(pp
->name
, "phandle") ||
2135 !strcmp(pp
->name
, "linux,phandle"))
2138 np
= of_find_node_by_path(pp
->value
);
2142 /* walk the alias backwards to extract the id and work out
2143 * the 'stem' string */
2144 while (isdigit(*(end
-1)) && end
> start
)
2148 if (kstrtoint(end
, 10, &id
) < 0)
2151 /* Allocate an alias_prop with enough space for the stem */
2152 ap
= dt_alloc(sizeof(*ap
) + len
+ 1, __alignof__(*ap
));
2155 memset(ap
, 0, sizeof(*ap
) + len
+ 1);
2157 of_alias_add(ap
, np
, id
, start
, len
);
2162 * of_alias_get_id - Get alias id for the given device_node
2163 * @np: Pointer to the given device_node
2164 * @stem: Alias stem of the given device_node
2166 * The function travels the lookup table to get the alias id for the given
2167 * device_node and alias stem. It returns the alias id if found.
2169 int of_alias_get_id(struct device_node
*np
, const char *stem
)
2171 struct alias_prop
*app
;
2174 mutex_lock(&of_mutex
);
2175 list_for_each_entry(app
, &aliases_lookup
, link
) {
2176 if (strcmp(app
->stem
, stem
) != 0)
2179 if (np
== app
->np
) {
2184 mutex_unlock(&of_mutex
);
2188 EXPORT_SYMBOL_GPL(of_alias_get_id
);
2191 * of_alias_get_highest_id - Get highest alias id for the given stem
2192 * @stem: Alias stem to be examined
2194 * The function travels the lookup table to get the highest alias id for the
2195 * given alias stem. It returns the alias id if found.
2197 int of_alias_get_highest_id(const char *stem
)
2199 struct alias_prop
*app
;
2202 mutex_lock(&of_mutex
);
2203 list_for_each_entry(app
, &aliases_lookup
, link
) {
2204 if (strcmp(app
->stem
, stem
) != 0)
2210 mutex_unlock(&of_mutex
);
2214 EXPORT_SYMBOL_GPL(of_alias_get_highest_id
);
2216 const __be32
*of_prop_next_u32(struct property
*prop
, const __be32
*cur
,
2219 const void *curv
= cur
;
2229 curv
+= sizeof(*cur
);
2230 if (curv
>= prop
->value
+ prop
->length
)
2234 *pu
= be32_to_cpup(curv
);
2237 EXPORT_SYMBOL_GPL(of_prop_next_u32
);
2239 const char *of_prop_next_string(struct property
*prop
, const char *cur
)
2241 const void *curv
= cur
;
2249 curv
+= strlen(cur
) + 1;
2250 if (curv
>= prop
->value
+ prop
->length
)
2255 EXPORT_SYMBOL_GPL(of_prop_next_string
);
2258 * of_console_check() - Test and setup console for DT setup
2259 * @dn - Pointer to device node
2260 * @name - Name to use for preferred console without index. ex. "ttyS"
2261 * @index - Index to use for preferred console.
2263 * Check if the given device node matches the stdout-path property in the
2264 * /chosen node. If it does then register it as the preferred console and return
2265 * TRUE. Otherwise return FALSE.
2267 bool of_console_check(struct device_node
*dn
, char *name
, int index
)
2269 if (!dn
|| dn
!= of_stdout
|| console_set_on_cmdline
)
2271 return !add_preferred_console(name
, index
,
2272 kstrdup(of_stdout_options
, GFP_KERNEL
));
2274 EXPORT_SYMBOL_GPL(of_console_check
);
2277 * of_find_next_cache_node - Find a node's subsidiary cache
2278 * @np: node of type "cpu" or "cache"
2280 * Returns a node pointer with refcount incremented, use
2281 * of_node_put() on it when done. Caller should hold a reference
2284 struct device_node
*of_find_next_cache_node(const struct device_node
*np
)
2286 struct device_node
*child
, *cache_node
;
2288 cache_node
= of_parse_phandle(np
, "l2-cache", 0);
2290 cache_node
= of_parse_phandle(np
, "next-level-cache", 0);
2295 /* OF on pmac has nodes instead of properties named "l2-cache"
2296 * beneath CPU nodes.
2298 if (!strcmp(np
->type
, "cpu"))
2299 for_each_child_of_node(np
, child
)
2300 if (!strcmp(child
->type
, "cache"))
2307 * of_find_last_cache_level - Find the level at which the last cache is
2308 * present for the given logical cpu
2310 * @cpu: cpu number(logical index) for which the last cache level is needed
2312 * Returns the the level at which the last cache is present. It is exactly
2313 * same as the total number of cache levels for the given logical cpu.
2315 int of_find_last_cache_level(unsigned int cpu
)
2317 u32 cache_level
= 0;
2318 struct device_node
*prev
= NULL
, *np
= of_cpu_device_node_get(cpu
);
2323 np
= of_find_next_cache_node(np
);
2326 of_property_read_u32(prev
, "cache-level", &cache_level
);
2332 * of_graph_parse_endpoint() - parse common endpoint node properties
2333 * @node: pointer to endpoint device_node
2334 * @endpoint: pointer to the OF endpoint data structure
2336 * The caller should hold a reference to @node.
2338 int of_graph_parse_endpoint(const struct device_node
*node
,
2339 struct of_endpoint
*endpoint
)
2341 struct device_node
*port_node
= of_get_parent(node
);
2343 WARN_ONCE(!port_node
, "%s(): endpoint %s has no parent node\n",
2344 __func__
, node
->full_name
);
2346 memset(endpoint
, 0, sizeof(*endpoint
));
2348 endpoint
->local_node
= node
;
2350 * It doesn't matter whether the two calls below succeed.
2351 * If they don't then the default value 0 is used.
2353 of_property_read_u32(port_node
, "reg", &endpoint
->port
);
2354 of_property_read_u32(node
, "reg", &endpoint
->id
);
2356 of_node_put(port_node
);
2360 EXPORT_SYMBOL(of_graph_parse_endpoint
);
2363 * of_graph_get_port_by_id() - get the port matching a given id
2364 * @parent: pointer to the parent device node
2365 * @id: id of the port
2367 * Return: A 'port' node pointer with refcount incremented. The caller
2368 * has to use of_node_put() on it when done.
2370 struct device_node
*of_graph_get_port_by_id(struct device_node
*parent
, u32 id
)
2372 struct device_node
*node
, *port
;
2374 node
= of_get_child_by_name(parent
, "ports");
2378 for_each_child_of_node(parent
, port
) {
2381 if (of_node_cmp(port
->name
, "port") != 0)
2383 of_property_read_u32(port
, "reg", &port_id
);
2392 EXPORT_SYMBOL(of_graph_get_port_by_id
);
2395 * of_graph_get_next_endpoint() - get next endpoint node
2396 * @parent: pointer to the parent device node
2397 * @prev: previous endpoint node, or NULL to get first
2399 * Return: An 'endpoint' node pointer with refcount incremented. Refcount
2400 * of the passed @prev node is decremented.
2402 struct device_node
*of_graph_get_next_endpoint(const struct device_node
*parent
,
2403 struct device_node
*prev
)
2405 struct device_node
*endpoint
;
2406 struct device_node
*port
;
2412 * Start by locating the port node. If no previous endpoint is specified
2413 * search for the first port node, otherwise get the previous endpoint
2417 struct device_node
*node
;
2419 node
= of_get_child_by_name(parent
, "ports");
2423 port
= of_get_child_by_name(parent
, "port");
2427 pr_err("graph: no port node found in %s\n",
2432 port
= of_get_parent(prev
);
2433 if (WARN_ONCE(!port
, "%s(): endpoint %s has no parent node\n",
2434 __func__
, prev
->full_name
))
2440 * Now that we have a port node, get the next endpoint by
2441 * getting the next child. If the previous endpoint is NULL this
2442 * will return the first child.
2444 endpoint
= of_get_next_child(port
, prev
);
2450 /* No more endpoints under this port, try the next one. */
2454 port
= of_get_next_child(parent
, port
);
2457 } while (of_node_cmp(port
->name
, "port"));
2460 EXPORT_SYMBOL(of_graph_get_next_endpoint
);
2463 * of_graph_get_endpoint_by_regs() - get endpoint node of specific identifiers
2464 * @parent: pointer to the parent device node
2465 * @port_reg: identifier (value of reg property) of the parent port node
2466 * @reg: identifier (value of reg property) of the endpoint node
2468 * Return: An 'endpoint' node pointer which is identified by reg and at the same
2469 * is the child of a port node identified by port_reg. reg and port_reg are
2470 * ignored when they are -1.
2472 struct device_node
*of_graph_get_endpoint_by_regs(
2473 const struct device_node
*parent
, int port_reg
, int reg
)
2475 struct of_endpoint endpoint
;
2476 struct device_node
*node
= NULL
;
2478 for_each_endpoint_of_node(parent
, node
) {
2479 of_graph_parse_endpoint(node
, &endpoint
);
2480 if (((port_reg
== -1) || (endpoint
.port
== port_reg
)) &&
2481 ((reg
== -1) || (endpoint
.id
== reg
)))
2487 EXPORT_SYMBOL(of_graph_get_endpoint_by_regs
);
2490 * of_graph_get_remote_endpoint() - get remote endpoint node
2491 * @node: pointer to a local endpoint device_node
2493 * Return: Remote endpoint node associated with remote endpoint node linked
2494 * to @node. Use of_node_put() on it when done.
2496 struct device_node
*of_graph_get_remote_endpoint(const struct device_node
*node
)
2498 /* Get remote endpoint node. */
2499 return of_parse_phandle(node
, "remote-endpoint", 0);
2501 EXPORT_SYMBOL(of_graph_get_remote_endpoint
);
2504 * of_graph_get_remote_port_parent() - get remote port's parent node
2505 * @node: pointer to a local endpoint device_node
2507 * Return: Remote device node associated with remote endpoint node linked
2508 * to @node. Use of_node_put() on it when done.
2510 struct device_node
*of_graph_get_remote_port_parent(
2511 const struct device_node
*node
)
2513 struct device_node
*np
;
2516 /* Get remote endpoint node. */
2517 np
= of_graph_get_remote_endpoint(node
);
2519 /* Walk 3 levels up only if there is 'ports' node. */
2520 for (depth
= 3; depth
&& np
; depth
--) {
2521 np
= of_get_next_parent(np
);
2522 if (depth
== 2 && of_node_cmp(np
->name
, "ports"))
2527 EXPORT_SYMBOL(of_graph_get_remote_port_parent
);
2530 * of_graph_get_remote_port() - get remote port node
2531 * @node: pointer to a local endpoint device_node
2533 * Return: Remote port node associated with remote endpoint node linked
2534 * to @node. Use of_node_put() on it when done.
2536 struct device_node
*of_graph_get_remote_port(const struct device_node
*node
)
2538 struct device_node
*np
;
2540 /* Get remote endpoint node. */
2541 np
= of_graph_get_remote_endpoint(node
);
2544 return of_get_next_parent(np
);
2546 EXPORT_SYMBOL(of_graph_get_remote_port
);
2549 * of_graph_get_remote_node() - get remote parent device_node for given port/endpoint
2550 * @node: pointer to parent device_node containing graph port/endpoint
2551 * @port: identifier (value of reg property) of the parent port node
2552 * @endpoint: identifier (value of reg property) of the endpoint node
2554 * Return: Remote device node associated with remote endpoint node linked
2555 * to @node. Use of_node_put() on it when done.
2557 struct device_node
*of_graph_get_remote_node(const struct device_node
*node
,
2558 u32 port
, u32 endpoint
)
2560 struct device_node
*endpoint_node
, *remote
;
2562 endpoint_node
= of_graph_get_endpoint_by_regs(node
, port
, endpoint
);
2563 if (!endpoint_node
) {
2564 pr_debug("no valid endpoint (%d, %d) for node %s\n",
2565 port
, endpoint
, node
->full_name
);
2569 remote
= of_graph_get_remote_port_parent(endpoint_node
);
2570 of_node_put(endpoint_node
);
2572 pr_debug("no valid remote node\n");
2576 if (!of_device_is_available(remote
)) {
2577 pr_debug("not available for remote node\n");
2583 EXPORT_SYMBOL(of_graph_get_remote_node
);