2 * Originally from Linux v4.9
3 * Copyright (C) 1996-2005 Paul Mackerras.
5 * Updates for PPC64 by Peter Bergner & David Engebretsen, IBM Corp.
6 * Updates for SPARC64 by David S. Miller
7 * Derived from PowerPC and Sparc prom.h files by Stephen Rothwell, IBM Corp.
9 * Copyright (c) 2017 Google, Inc
10 * Written by Simon Glass <sjg@chromium.org>
13 * Copyright (c) 2017 Google, Inc
15 * SPDX-License-Identifier: GPL-2.0+
18 #ifndef _DM_OF_ACCESS_H
19 #define _DM_OF_ACCESS_H
24 * of_find_all_nodes - Get next node in global list
25 * @prev: Previous node or NULL to start iteration
26 * of_node_put() will be called on it
28 * Returns a node pointer with refcount incremented, use
29 * of_node_put() on it when done.
31 struct device_node *of_find_all_nodes(struct device_node *prev);
33 #define for_each_of_allnodes_from(from, dn) \
34 for (dn = of_find_all_nodes(from); dn; dn = of_find_all_nodes(dn))
35 #define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn)
37 /* Dummy functions to mirror Linux. These are not used in U-Boot */
38 #define of_node_get(x) (x)
39 static inline void of_node_put(const struct device_node *np) { }
42 * of_n_addr_cells() - Get the number of address cells for a node
44 * This walks back up the tree to find the closest #address-cells property
45 * which controls the given node.
47 * @np: Node pointer to check
48 * @return number of address cells this node uses
50 int of_n_addr_cells(const struct device_node *np);
53 * of_n_size_cells() - Get the number of size cells for a node
55 * This walks back up the tree to find the closest #size-cells property
56 * which controls the given node.
58 * @np: Node pointer to check
59 * @return number of size cells this node uses
61 int of_n_size_cells(const struct device_node *np);
64 * of_find_property() - find a property in a node
66 * @np: Pointer to device node holding property
67 * @name: Name of property
68 * @lenp: If non-NULL, returns length of property
69 * @return pointer to property, or NULL if not found
71 struct property *of_find_property(const struct device_node *np,
72 const char *name, int *lenp);
75 * of_get_property() - get a property value
77 * Find a property with a given name for a given node and return the value.
79 * @np: Pointer to device node holding property
80 * @name: Name of property
81 * @lenp: If non-NULL, returns length of property
82 * @return pointer to property value, or NULL if not found
84 const void *of_get_property(const struct device_node *np, const char *name,
88 * of_device_is_compatible() - Check if the node matches given constraints
89 * @device: pointer to node
90 * @compat: required compatible string, NULL or "" for any match
91 * @type: required device_type value, NULL or "" for any match
92 * @name: required node name, NULL or "" for any match
94 * Checks if the given @compat, @type and @name strings match the
95 * properties of the given @device. A constraints can be skipped by
96 * passing NULL or an empty string as the constraint.
98 * @return 0 for no match, and a positive integer on match. The return
99 * value is a relative score with larger values indicating better
100 * matches. The score is weighted for the most specific compatible value
101 * to get the highest score. Matching type is next, followed by matching
102 * name. Practically speaking, this results in the following priority
105 * 1. specific compatible && type && name
106 * 2. specific compatible && type
107 * 3. specific compatible && name
108 * 4. specific compatible
109 * 5. general compatible && type && name
110 * 6. general compatible && type
111 * 7. general compatible && name
112 * 8. general compatible
117 int of_device_is_compatible(const struct device_node *np, const char *compat,
118 const char *type, const char *name);
121 * of_device_is_available() - check if a device is available for use
123 * @device: Node to check for availability
125 * @return true if the status property is absent or set to "okay", false
128 bool of_device_is_available(const struct device_node *np);
131 * of_get_parent() - Get a node's parent, if any
133 * @node: Node to check
134 * @eturns a node pointer, or NULL if none
136 struct device_node *of_get_parent(const struct device_node *np);
139 * of_find_node_opts_by_path() - Find a node matching a full OF path
141 * @path: Either the full path to match, or if the path does not start with
142 * '/', the name of a property of the /aliases node (an alias). In the
143 * case of an alias, the node matching the alias' value will be returned.
144 * @opts: Address of a pointer into which to store the start of an options
145 * string appended to the end of the path with a ':' separator. Can be NULL
150 * foo/bar Valid alias + relative path
152 * @return a node pointer or NULL if not found
154 struct device_node *of_find_node_opts_by_path(const char *path,
157 static inline struct device_node *of_find_node_by_path(const char *path)
159 return of_find_node_opts_by_path(path, NULL);
163 * of_find_compatible_node() - find a node based on its compatible string
165 * Find a node based on type and one of the tokens in its "compatible" property
166 * @from: Node to start searching from or NULL. the node you pass will not be
167 * searched, only the next one will; typically, you pass what the previous
169 * @type: The type string to match "device_type" or NULL to ignore
170 * @compatible: The string to match to one of the tokens in the device
172 * @return node pointer or NULL if not found
174 struct device_node *of_find_compatible_node(struct device_node *from,
175 const char *type, const char *compatible);
178 * of_find_node_by_phandle() - Find a node given a phandle
180 * @handle: phandle of the node to find
182 * @return node pointer, or NULL if not found
184 struct device_node *of_find_node_by_phandle(phandle handle);
187 * of_read_u32() - Find and read a 32-bit integer from a property
189 * Search for a property in a device node and read a 32-bit value from
192 * @np: device node from which the property value is to be read.
193 * @propname: name of the property to be searched.
194 * @outp: pointer to return value, modified only if return value is 0.
196 * @return 0 on success, -EINVAL if the property does not exist,
197 * -ENODATA if property does not have a value, and -EOVERFLOW if the
198 * property data isn't large enough.
200 int of_read_u32(const struct device_node *np, const char *propname, u32 *outp);
203 * of_read_u32_array() - Find and read an array of 32 bit integers
205 * Search for a property in a device node and read 32-bit value(s) from
208 * @np: device node from which the property value is to be read.
209 * @propname: name of the property to be searched.
210 * @out_values: pointer to return value, modified only if return value is 0.
211 * @sz: number of array elements to read
212 * @return 0 on success, -EINVAL if the property does not exist, -ENODATA
213 * if property does not have a value, and -EOVERFLOW is longer than sz.
215 int of_read_u32_array(const struct device_node *np, const char *propname,
216 u32 *out_values, size_t sz);
219 * of_property_match_string() - Find string in a list and return index
221 * This function searches a string list property and returns the index
222 * of a specific string value.
224 * @np: pointer to node containing string list property
225 * @propname: string list property name
226 * @string: pointer to string to search for in string list
227 * @return 0 on success, -EINVAL if the property does not exist, -ENODATA
228 * if property does not have a value, and -EOVERFLOW is longer than sz.
230 int of_property_match_string(const struct device_node *np, const char *propname,
233 int of_property_read_string_helper(const struct device_node *np,
234 const char *propname, const char **out_strs,
235 size_t sz, int index);
238 * of_property_read_string_index() - Find and read a string from a multiple
240 * @np: device node from which the property value is to be read.
241 * @propname: name of the property to be searched.
242 * @index: index of the string in the list of strings
243 * @out_string: pointer to null terminated return string, modified only if
246 * Search for a property in a device tree node and retrieve a null
247 * terminated string value (pointer to data, not a copy) in the list of strings
248 * contained in that property.
249 * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
250 * property does not have a value, and -EILSEQ if the string is not
251 * null-terminated within the length of the property data.
253 * The out_string pointer is modified only if a valid string can be decoded.
255 static inline int of_property_read_string_index(const struct device_node *np,
256 const char *propname,
257 int index, const char **output)
259 int rc = of_property_read_string_helper(np, propname, output, 1, index);
260 return rc < 0 ? rc : 0;
264 * of_parse_phandle - Resolve a phandle property to a device_node pointer
265 * @np: Pointer to device node holding phandle property
266 * @phandle_name: Name of property holding a phandle value
267 * @index: For properties holding a table of phandles, this is the index into
270 * Returns the device_node pointer with refcount incremented. Use
271 * of_node_put() on it when done.
273 struct device_node *of_parse_phandle(const struct device_node *np,
274 const char *phandle_name, int index);
277 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
279 * @np: pointer to a device tree node containing a list
280 * @list_name: property name that contains a list
281 * @cells_name: property name that specifies phandles' arguments count
282 * @index: index of a phandle to parse out
283 * @out_args: optional pointer to output arguments structure (will be filled)
284 * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
285 * @list_name does not exist, -EINVAL if a phandle was not found,
286 * @cells_name could not be found, the arguments were truncated or there
287 * were too many arguments.
289 * This function is useful to parse lists of phandles and their arguments.
290 * Returns 0 on success and fills out_args, on error returns appropriate
293 * Caller is responsible to call of_node_put() on the returned out_args->np
307 * list = <&phandle1 1 2 &phandle2 3>;
310 * To get a device_node of the `node2' node you may call this:
311 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
313 int of_parse_phandle_with_args(const struct device_node *np,
314 const char *list_name, const char *cells_name,
315 int index, struct of_phandle_args *out_args);
318 * of_alias_scan() - Scan all properties of the 'aliases' node
320 * The function scans all the properties of the 'aliases' node and populates
321 * the lookup table with the properties. It returns the number of alias
322 * properties found, or an error code in case of failure.
324 * @return 9 if OK, -ENOMEM if not enough memory
326 int of_alias_scan(void);
329 * of_alias_get_id - Get alias id for the given device_node
331 * Travels the lookup table to get the alias id for the given device_node and
334 * @np: Pointer to the given device_node
335 * @stem: Alias stem of the given device_node
336 * @return alias ID, if found, else -ENODEV
338 int of_alias_get_id(const struct device_node *np, const char *stem);
341 * of_get_stdout() - Get node to use for stdout
343 * @return node referred to by stdout-path alias, or NULL if none
345 struct device_node *of_get_stdout(void);