iwlwifi: introduce host commands callbacks
[linux/fpc-iii.git] / drivers / of / base.c
blob80c9deca5f35aa3313245d099215d5f387c687b1
1 /*
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.
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/spinlock.h>
23 struct device_node *allnodes;
25 /* use when traversing tree through the allnext, child, sibling,
26 * or parent members of struct device_node.
28 DEFINE_RWLOCK(devtree_lock);
30 int of_n_addr_cells(struct device_node *np)
32 const int *ip;
34 do {
35 if (np->parent)
36 np = np->parent;
37 ip = of_get_property(np, "#address-cells", NULL);
38 if (ip)
39 return *ip;
40 } while (np->parent);
41 /* No #address-cells property for the root node */
42 return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
44 EXPORT_SYMBOL(of_n_addr_cells);
46 int of_n_size_cells(struct device_node *np)
48 const int *ip;
50 do {
51 if (np->parent)
52 np = np->parent;
53 ip = of_get_property(np, "#size-cells", NULL);
54 if (ip)
55 return *ip;
56 } while (np->parent);
57 /* No #size-cells property for the root node */
58 return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
60 EXPORT_SYMBOL(of_n_size_cells);
62 struct property *of_find_property(const struct device_node *np,
63 const char *name,
64 int *lenp)
66 struct property *pp;
68 read_lock(&devtree_lock);
69 for (pp = np->properties; pp != 0; pp = pp->next) {
70 if (of_prop_cmp(pp->name, name) == 0) {
71 if (lenp != 0)
72 *lenp = pp->length;
73 break;
76 read_unlock(&devtree_lock);
78 return pp;
80 EXPORT_SYMBOL(of_find_property);
83 * Find a property with a given name for a given node
84 * and return the value.
86 const void *of_get_property(const struct device_node *np, const char *name,
87 int *lenp)
89 struct property *pp = of_find_property(np, name, lenp);
91 return pp ? pp->value : NULL;
93 EXPORT_SYMBOL(of_get_property);
95 /** Checks if the given "compat" string matches one of the strings in
96 * the device's "compatible" property
98 int of_device_is_compatible(const struct device_node *device,
99 const char *compat)
101 const char* cp;
102 int cplen, l;
104 cp = of_get_property(device, "compatible", &cplen);
105 if (cp == NULL)
106 return 0;
107 while (cplen > 0) {
108 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
109 return 1;
110 l = strlen(cp) + 1;
111 cp += l;
112 cplen -= l;
115 return 0;
117 EXPORT_SYMBOL(of_device_is_compatible);
120 * of_get_parent - Get a node's parent if any
121 * @node: Node to get parent
123 * Returns a node pointer with refcount incremented, use
124 * of_node_put() on it when done.
126 struct device_node *of_get_parent(const struct device_node *node)
128 struct device_node *np;
130 if (!node)
131 return NULL;
133 read_lock(&devtree_lock);
134 np = of_node_get(node->parent);
135 read_unlock(&devtree_lock);
136 return np;
138 EXPORT_SYMBOL(of_get_parent);
141 * of_get_next_parent - Iterate to a node's parent
142 * @node: Node to get parent of
144 * This is like of_get_parent() except that it drops the
145 * refcount on the passed node, making it suitable for iterating
146 * through a node's parents.
148 * Returns a node pointer with refcount incremented, use
149 * of_node_put() on it when done.
151 struct device_node *of_get_next_parent(struct device_node *node)
153 struct device_node *parent;
155 if (!node)
156 return NULL;
158 read_lock(&devtree_lock);
159 parent = of_node_get(node->parent);
160 of_node_put(node);
161 read_unlock(&devtree_lock);
162 return parent;
166 * of_get_next_child - Iterate a node childs
167 * @node: parent node
168 * @prev: previous child of the parent node, or NULL to get first
170 * Returns a node pointer with refcount incremented, use
171 * of_node_put() on it when done.
173 struct device_node *of_get_next_child(const struct device_node *node,
174 struct device_node *prev)
176 struct device_node *next;
178 read_lock(&devtree_lock);
179 next = prev ? prev->sibling : node->child;
180 for (; next; next = next->sibling)
181 if (of_node_get(next))
182 break;
183 of_node_put(prev);
184 read_unlock(&devtree_lock);
185 return next;
187 EXPORT_SYMBOL(of_get_next_child);
190 * of_find_node_by_path - Find a node matching a full OF path
191 * @path: The full path to match
193 * Returns a node pointer with refcount incremented, use
194 * of_node_put() on it when done.
196 struct device_node *of_find_node_by_path(const char *path)
198 struct device_node *np = allnodes;
200 read_lock(&devtree_lock);
201 for (; np; np = np->allnext) {
202 if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
203 && of_node_get(np))
204 break;
206 read_unlock(&devtree_lock);
207 return np;
209 EXPORT_SYMBOL(of_find_node_by_path);
212 * of_find_node_by_name - Find a node by its "name" property
213 * @from: The node to start searching from or NULL, the node
214 * you pass will not be searched, only the next one
215 * will; typically, you pass what the previous call
216 * returned. of_node_put() will be called on it
217 * @name: The name string to match against
219 * Returns a node pointer with refcount incremented, use
220 * of_node_put() on it when done.
222 struct device_node *of_find_node_by_name(struct device_node *from,
223 const char *name)
225 struct device_node *np;
227 read_lock(&devtree_lock);
228 np = from ? from->allnext : allnodes;
229 for (; np; np = np->allnext)
230 if (np->name && (of_node_cmp(np->name, name) == 0)
231 && of_node_get(np))
232 break;
233 of_node_put(from);
234 read_unlock(&devtree_lock);
235 return np;
237 EXPORT_SYMBOL(of_find_node_by_name);
240 * of_find_node_by_type - Find a node by its "device_type" property
241 * @from: The node to start searching from, or NULL to start searching
242 * the entire device tree. The node you pass will not be
243 * searched, only the next one will; typically, you pass
244 * what the previous call returned. of_node_put() will be
245 * called on from for you.
246 * @type: The type string to match against
248 * Returns a node pointer with refcount incremented, use
249 * of_node_put() on it when done.
251 struct device_node *of_find_node_by_type(struct device_node *from,
252 const char *type)
254 struct device_node *np;
256 read_lock(&devtree_lock);
257 np = from ? from->allnext : allnodes;
258 for (; np; np = np->allnext)
259 if (np->type && (of_node_cmp(np->type, type) == 0)
260 && of_node_get(np))
261 break;
262 of_node_put(from);
263 read_unlock(&devtree_lock);
264 return np;
266 EXPORT_SYMBOL(of_find_node_by_type);
269 * of_find_compatible_node - Find a node based on type and one of the
270 * tokens in its "compatible" property
271 * @from: The node to start searching from or NULL, the node
272 * you pass will not be searched, only the next one
273 * will; typically, you pass what the previous call
274 * returned. of_node_put() will be called on it
275 * @type: The type string to match "device_type" or NULL to ignore
276 * @compatible: The string to match to one of the tokens in the device
277 * "compatible" list.
279 * Returns a node pointer with refcount incremented, use
280 * of_node_put() on it when done.
282 struct device_node *of_find_compatible_node(struct device_node *from,
283 const char *type, const char *compatible)
285 struct device_node *np;
287 read_lock(&devtree_lock);
288 np = from ? from->allnext : allnodes;
289 for (; np; np = np->allnext) {
290 if (type
291 && !(np->type && (of_node_cmp(np->type, type) == 0)))
292 continue;
293 if (of_device_is_compatible(np, compatible) && of_node_get(np))
294 break;
296 of_node_put(from);
297 read_unlock(&devtree_lock);
298 return np;
300 EXPORT_SYMBOL(of_find_compatible_node);
303 * of_match_node - Tell if an device_node has a matching of_match structure
304 * @matches: array of of device match structures to search in
305 * @node: the of device structure to match against
307 * Low level utility function used by device matching.
309 const struct of_device_id *of_match_node(const struct of_device_id *matches,
310 const struct device_node *node)
312 while (matches->name[0] || matches->type[0] || matches->compatible[0]) {
313 int match = 1;
314 if (matches->name[0])
315 match &= node->name
316 && !strcmp(matches->name, node->name);
317 if (matches->type[0])
318 match &= node->type
319 && !strcmp(matches->type, node->type);
320 if (matches->compatible[0])
321 match &= of_device_is_compatible(node,
322 matches->compatible);
323 if (match)
324 return matches;
325 matches++;
327 return NULL;
329 EXPORT_SYMBOL(of_match_node);
332 * of_find_matching_node - Find a node based on an of_device_id match
333 * table.
334 * @from: The node to start searching from or NULL, the node
335 * you pass will not be searched, only the next one
336 * will; typically, you pass what the previous call
337 * returned. of_node_put() will be called on it
338 * @matches: array of of device match structures to search in
340 * Returns a node pointer with refcount incremented, use
341 * of_node_put() on it when done.
343 struct device_node *of_find_matching_node(struct device_node *from,
344 const struct of_device_id *matches)
346 struct device_node *np;
348 read_lock(&devtree_lock);
349 np = from ? from->allnext : allnodes;
350 for (; np; np = np->allnext) {
351 if (of_match_node(matches, np) && of_node_get(np))
352 break;
354 of_node_put(from);
355 read_unlock(&devtree_lock);
356 return np;
358 EXPORT_SYMBOL(of_find_matching_node);