1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * Originally from Linux v4.9
4 * Copyright (C) 1996-2005 Paul Mackerras.
6 * Updates for PPC64 by Peter Bergner & David Engebretsen, IBM Corp.
7 * Updates for SPARC64 by David S. Miller
8 * Derived from PowerPC and Sparc prom.h files by Stephen Rothwell, IBM Corp.
10 * Copyright (c) 2017 Google, Inc
11 * Written by Simon Glass <sjg@chromium.org>
14 * Copyright (c) 2017 Google, Inc
17 #ifndef _DM_OF_ACCESS_H
18 #define _DM_OF_ACCESS_H
23 * of_find_all_nodes - Get next node in global list
24 * @prev: Previous node or NULL to start iteration
25 * of_node_put() will be called on it
27 * Returns a node pointer with refcount incremented, use
28 * of_node_put() on it when done.
30 struct device_node *of_find_all_nodes(struct device_node *prev);
32 #define for_each_of_allnodes_from(from, dn) \
33 for (dn = of_find_all_nodes(from); dn; dn = of_find_all_nodes(dn))
34 #define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn)
36 /* Dummy functions to mirror Linux. These are not used in U-Boot */
37 #define of_node_get(x) (x)
38 static inline void of_node_put(const struct device_node *np) { }
41 * of_n_addr_cells() - Get the number of address cells for a node
43 * This walks back up the tree to find the closest #address-cells property
44 * which controls the given node.
46 * @np: Node pointer to check
47 * Return: number of address cells this node uses
49 int of_n_addr_cells(const struct device_node *np);
52 * of_n_size_cells() - Get the number of size cells for a node
54 * This walks back up the tree to find the closest #size-cells property
55 * which controls the given node.
57 * @np: Node pointer to check
58 * Return: number of size cells this node uses
60 int of_n_size_cells(const struct device_node *np);
63 * of_simple_addr_cells() - Get the address cells property in a node
65 * This function matches fdt_address_cells().
67 * @np: Node pointer to check
68 * Return: value of #address-cells property in this node, or 2 if none
70 int of_simple_addr_cells(const struct device_node *np);
73 * of_simple_size_cells() - Get the size cells property in a node
75 * This function matches fdt_size_cells().
77 * @np: Node pointer to check
78 * Return: value of #size-cells property in this node, or 2 if none
80 int of_simple_size_cells(const struct device_node *np);
83 * of_find_property() - find a property in a node
85 * @np: Pointer to device node holding property
86 * @name: Name of property
87 * @lenp: If non-NULL, returns length of property
88 * Return: pointer to property, or NULL if not found
90 struct property *of_find_property(const struct device_node *np,
91 const char *name, int *lenp);
94 * of_get_property() - get a property value
96 * Find a property with a given name for a given node and return the value.
98 * @np: Pointer to device node holding property
99 * @name: Name of property
100 * @lenp: If non-NULL, returns length of property
101 * Return: pointer to property value, or NULL if not found
103 const void *of_get_property(const struct device_node *np, const char *name,
107 * of_get_first_property()- get to the pointer of the first property
109 * Get pointer to the first property of the node, it is used to iterate
110 * and read all the property with of_get_next_property_by_prop().
112 * @np: Pointer to device node
113 * Return: pointer to property or NULL if not found
115 const struct property *of_get_first_property(const struct device_node *np);
118 * of_get_next_property() - get to the pointer of the next property
120 * Get pointer to the next property of the node, it is used to iterate
121 * and read all the property with of_get_property_by_prop().
123 * @np: Pointer to device node
124 * @property: pointer of the current property
125 * Return: pointer to next property or NULL if not found
127 const struct property *of_get_next_property(const struct device_node *np,
128 const struct property *property);
131 * of_get_property_by_prop() - get a property value of a node property
133 * Get value for the property identified by node and property pointer.
135 * @np: Pointer to device node
136 * @property: pointer of the property to read
137 * @name: place to property name on success
138 * @lenp: place to put length on success
139 * Return: pointer to property value or NULL if error
141 const void *of_get_property_by_prop(const struct device_node *np,
142 const struct property *property,
147 * of_device_is_compatible() - Check if the node matches given constraints
148 * @np: Pointer to device node
149 * @compat: required compatible string, NULL or "" for any match
150 * @type: required device_type value, NULL or "" for any match
151 * @name: required node name, NULL or "" for any match
153 * Checks if the given @compat, @type and @name strings match the
154 * properties of the given @device. A constraints can be skipped by
155 * passing NULL or an empty string as the constraint.
157 * Return: 0 for no match, and a positive integer on match. The return
158 * value is a relative score with larger values indicating better
159 * matches. The score is weighted for the most specific compatible value
160 * to get the highest score. Matching type is next, followed by matching
161 * name. Practically speaking, this results in the following priority
164 * 1. specific compatible && type && name
165 * 2. specific compatible && type
166 * 3. specific compatible && name
167 * 4. specific compatible
168 * 5. general compatible && type && name
169 * 6. general compatible && type
170 * 7. general compatible && name
171 * 8. general compatible
176 int of_device_is_compatible(const struct device_node *np, const char *compat,
177 const char *type, const char *name);
180 * of_device_is_available() - check if a device is available for use
182 * @np: Pointer to device node to check for availability
184 * Return: true if the status property is absent or set to "okay", false
187 bool of_device_is_available(const struct device_node *np);
190 * of_get_parent() - Get a node's parent, if any
192 * @np: Pointer to device node to check
193 * Return: a node pointer, or NULL if none
195 struct device_node *of_get_parent(const struct device_node *np);
198 * of_find_node_opts_by_path() - Find a node matching a full OF path
200 * Note that alias processing is only available on the control FDT (gd->of_root).
201 * For other trees it is skipped, so any attempt to obtain an alias will result
204 * @root: Root node of the tree to use. If this is NULL, then gd->of_root is used
205 * @path: Either the full path to match, or if the path does not start with
206 * '/', the name of a property of the /aliases node (an alias). In the
207 * case of an alias, the node matching the alias' value will be returned.
208 * @opts: Address of a pointer into which to store the start of an options
209 * string appended to the end of the path with a ':' separator. Can be NULL
214 * foo/bar Valid alias + relative path
216 * Return: a node pointer or NULL if not found
218 struct device_node *of_find_node_opts_by_path(struct device_node *root,
222 static inline struct device_node *of_find_node_by_path(const char *path)
224 return of_find_node_opts_by_path(NULL, path, NULL);
228 * of_find_compatible_node() - find a node based on its compatible string
230 * Find a node based on type and one of the tokens in its "compatible" property
231 * @from: Node to start searching from or NULL. the node you pass will not be
232 * searched, only the next one will; typically, you pass what the previous
234 * @type: The type string to match "device_type" or NULL to ignore
235 * @compatible: The string to match to one of the tokens in the device
237 * Return: node pointer or NULL if not found
239 struct device_node *of_find_compatible_node(struct device_node *from,
240 const char *type, const char *compatible);
243 * of_find_node_by_prop_value() - find a node with a given property value
245 * Find a node based on a property value.
246 * @from: Node to start searching from or NULL. the node you pass will not be
247 * searched, only the next one will; typically, you pass what the previous
249 * @propname: property name to check
250 * @propval: property value to search for
251 * @proplen: length of the value in propval
252 * Return: node pointer or NULL if not found
254 struct device_node *of_find_node_by_prop_value(struct device_node *from,
255 const char *propname,
259 * of_find_node_by_phandle() - Find a node given a phandle
261 * @root: root node to start from (NULL for default device tree)
262 * @handle: phandle of the node to find
264 * Return: node pointer, or NULL if not found
266 struct device_node *of_find_node_by_phandle(struct device_node *root,
270 * of_read_u8() - Find and read a 8-bit integer from a property
272 * Search for a property in a device node and read a 8-bit value from
275 * @np: device node from which the property value is to be read.
276 * @propname: name of the property to be searched.
277 * @outp: pointer to return value, modified only if return value is 0.
279 * Return: 0 on success, -EINVAL if the property does not exist,
280 * -ENODATA if property does not have a value, and -EOVERFLOW if the
281 * property data isn't large enough.
283 int of_read_u8(const struct device_node *np, const char *propname, u8 *outp);
286 * of_read_u16() - Find and read a 16-bit integer from a property
288 * Search for a property in a device node and read a 16-bit value from
291 * @np: device node from which the property value is to be read.
292 * @propname: name of the property to be searched.
293 * @outp: pointer to return value, modified only if return value is 0.
295 * Return: 0 on success, -EINVAL if the property does not exist,
296 * -ENODATA if property does not have a value, and -EOVERFLOW if the
297 * property data isn't large enough.
299 int of_read_u16(const struct device_node *np, const char *propname, u16 *outp);
302 * of_read_u32() - Find and read a 32-bit integer from a property
304 * Search for a property in a device node and read a 32-bit value from
307 * @np: device node from which the property value is to be read.
308 * @propname: name of the property to be searched.
309 * @outp: pointer to return value, modified only if return value is 0.
311 * Return: 0 on success, -EINVAL if the property does not exist,
312 * -ENODATA if property does not have a value, and -EOVERFLOW if the
313 * property data isn't large enough.
315 int of_read_u32(const struct device_node *np, const char *propname, u32 *outp);
318 * of_read_u32_index() - Find and read a 32-bit value from a multi-value
321 * Search for a property in a device node and read a 32-bit value from
324 * @np: device node from which the property value is to be read.
325 * @propname: name of the property to be searched.
326 * @index: index of the u32 in the list of values
327 * @outp: pointer to return value, modified only if return value is 0.
330 * 0 on success, -EINVAL if the property does not exist, or -EOVERFLOW if the
331 * property data isn't large enough.
333 int of_read_u32_index(const struct device_node *np, const char *propname,
334 int index, u32 *outp);
337 * of_read_u64() - Find and read a 64-bit integer from a property
339 * Search for a property in a device node and read a 64-bit value from
342 * @np: device node from which the property value is to be read.
343 * @propname: name of the property to be searched.
344 * @outp: pointer to return value, modified only if return value is 0.
347 * 0 on success, -EINVAL if the property does not exist, or -EOVERFLOW if the
348 * property data isn't large enough.
350 int of_read_u64(const struct device_node *np, const char *propname, u64 *outp);
353 * of_read_u32_array() - Find and read an array of 32 bit integers
355 * Search for a property in a device node and read 32-bit value(s) from
358 * @np: device node from which the property value is to be read.
359 * @propname: name of the property to be searched.
360 * @out_values: pointer to return value, modified only if return value is 0.
361 * @sz: number of array elements to read
363 * 0 on success, -EINVAL if the property does not exist, or -EOVERFLOW if
366 int of_read_u32_array(const struct device_node *np, const char *propname,
367 u32 *out_values, size_t sz);
370 * of_property_match_string() - Find string in a list and return index
372 * This function searches a string list property and returns the index
373 * of a specific string value.
375 * @np: pointer to node containing string list property
376 * @propname: string list property name
377 * @string: pointer to string to search for in string list
379 * 0 on success, -EINVAL if the property does not exist, -ENODATA
380 * if property does not have a value, and -EOVERFLOW is longer than sz.
382 int of_property_match_string(const struct device_node *np, const char *propname,
385 int of_property_read_string_helper(const struct device_node *np,
386 const char *propname, const char **out_strs,
387 size_t sz, int index);
390 * of_property_read_string_index() - Find and read a string from a multiple
392 * @np: device node from which the property value is to be read.
393 * @propname: name of the property to be searched.
394 * @index: index of the string in the list of strings
395 * @output: pointer to null terminated return string, modified only if
398 * Search for a property in a device tree node and retrieve a null
399 * terminated string value (pointer to data, not a copy) in the list of strings
400 * contained in that property.
403 * 0 on success, -EINVAL if the property does not exist, -ENODATA if
404 * property does not have a value, and -EILSEQ if the string is not
405 * null-terminated within the length of the property data.
407 * The out_string pointer is modified only if a valid string can be decoded.
409 static inline int of_property_read_string_index(const struct device_node *np,
410 const char *propname,
411 int index, const char **output)
413 int rc = of_property_read_string_helper(np, propname, output, 1, index);
414 return rc < 0 ? rc : 0;
418 * of_property_count_strings() - Find and return the number of strings from a
419 * multiple strings property.
420 * @np: device node from which the property value is to be read.
421 * @propname: name of the property to be searched.
423 * Search for a property in a device tree node and retrieve the number of null
424 * terminated string contain in it.
427 * the number of strings on success, -EINVAL if the property does not exist,
428 * -ENODATA if property does not have a value, and -EILSEQ if the string is
429 * not null-terminated within the length of the property data.
431 static inline int of_property_count_strings(const struct device_node *np,
432 const char *propname)
434 return of_property_read_string_helper(np, propname, NULL, 0, 0);
438 * of_parse_phandle - Resolve a phandle property to a device_node pointer
439 * @np: Pointer to device node holding phandle property
440 * @phandle_name: Name of property holding a phandle value
441 * @index: For properties holding a table of phandles, this is the index into
445 * the device_node pointer with refcount incremented. Use
446 * of_node_put() on it when done.
448 struct device_node *of_parse_phandle(const struct device_node *np,
449 const char *phandle_name, int index);
452 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
454 * @np: pointer to a device tree node containing a list
455 * @list_name: property name that contains a list
456 * @cells_name: property name that specifies phandles' arguments count
457 * @cells_count: Cell count to use if @cells_name is NULL
458 * @index: index of a phandle to parse out
459 * @out_args: optional pointer to output arguments structure (will be filled)
461 * 0 on success (with @out_args filled out if not NULL), -ENOENT if
462 * @list_name does not exist, -EINVAL if a phandle was not found,
463 * @cells_name could not be found, the arguments were truncated or there
464 * were too many arguments.
466 * This function is useful to parse lists of phandles and their arguments.
467 * Returns 0 on success and fills out_args, on error returns appropriate
470 * Caller is responsible to call of_node_put() on the returned out_args->np
484 * list = <&phandle1 1 2 &phandle2 3>;
487 * To get a device_node of the `node2' node you may call this:
488 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
490 int of_parse_phandle_with_args(const struct device_node *np,
491 const char *list_name, const char *cells_name,
492 int cells_count, int index,
493 struct of_phandle_args *out_args);
496 * of_count_phandle_with_args() - Count the number of phandle in a list
498 * @np: pointer to a device tree node containing a list
499 * @list_name: property name that contains a list
500 * @cells_name: property name that specifies phandles' arguments count
501 * @cells_count: Cell count to use if @cells_name is NULL
503 * number of phandle found, -ENOENT if @list_name does not exist,
504 * -EINVAL if a phandle was not found, @cells_name could not be found,
505 * the arguments were truncated or there were too many arguments.
507 * Returns number of phandle found on success, on error returns appropriate
510 int of_count_phandle_with_args(const struct device_node *np,
511 const char *list_name, const char *cells_name,
515 * of_alias_scan() - Scan all properties of the 'aliases' node
517 * The function scans all the properties of the 'aliases' node and populates
518 * the lookup table with the properties. It returns the number of alias
519 * properties found, or an error code in case of failure.
521 * Return: 9 if OK, -ENOMEM if not enough memory
523 int of_alias_scan(void);
526 * of_alias_get_id - Get alias id for the given device_node
528 * Travels the lookup table to get the alias id for the given device_node and
531 * @np: Pointer to the given device_node
532 * @stem: Alias stem of the given device_node
533 * Return: alias ID, if found, else -ENODEV
535 int of_alias_get_id(const struct device_node *np, const char *stem);
538 * of_alias_get_highest_id - Get highest alias id for the given stem
539 * @stem: Alias stem to be examined
541 * The function travels the lookup table to get the highest alias id for the
543 * Return: alias ID, if found, else -1
545 int of_alias_get_highest_id(const char *stem);
548 * of_get_stdout() - Get node to use for stdout
550 * Return: node referred to by stdout-path alias, or NULL if none
552 struct device_node *of_get_stdout(void);
555 * of_write_prop() - Write a property to the device tree
557 * @np: device node to which the property value is to be written
558 * @propname: name of the property to write
559 * @value: value of the property
560 * @len: length of the property in bytes
561 * Returns: 0 if OK, -ve on error
563 int of_write_prop(struct device_node *np, const char *propname, int len,
567 * of_add_subnode() - add a new subnode to a node
569 * @node: parent node to add to
570 * @name: name of subnode
571 * @len: length of name (so the caller does not need to nul-terminate a
572 * partial string), or -1 for strlen(@name)
573 * @subnodep: returns pointer to new subnode (valid if the function returns 0
575 * Returns 0 if OK, -EEXIST if already exists, -ENOMEM if out of memory, other
578 int of_add_subnode(struct device_node *node, const char *name, int len,
579 struct device_node **subnodep);