diff options
Diffstat (limited to 'include/dm/of_access.h')
| -rw-r--r-- | include/dm/of_access.h | 444 |
1 files changed, 444 insertions, 0 deletions
diff --git a/include/dm/of_access.h b/include/dm/of_access.h new file mode 100644 index 0000000..13fedb7 --- /dev/null +++ b/include/dm/of_access.h @@ -0,0 +1,444 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Originally from Linux v4.9 + * Copyright (C) 1996-2005 Paul Mackerras. + * + * Updates for PPC64 by Peter Bergner & David Engebretsen, IBM Corp. + * Updates for SPARC64 by David S. Miller + * Derived from PowerPC and Sparc prom.h files by Stephen Rothwell, IBM Corp. + * + * Copyright (c) 2017 Google, Inc + * Written by Simon Glass <sjg@chromium.org> + * + * Modified for U-Boot + * Copyright (c) 2017 Google, Inc + */ + +#ifndef _DM_OF_ACCESS_H +#define _DM_OF_ACCESS_H + +#include <dm/of.h> + +/** + * of_find_all_nodes - Get next node in global list + * @prev: Previous node or NULL to start iteration + * of_node_put() will be called on it + * + * Returns a node pointer with refcount incremented, use + * of_node_put() on it when done. + */ +struct device_node *of_find_all_nodes(struct device_node *prev); + +#define for_each_of_allnodes_from(from, dn) \ + for (dn = of_find_all_nodes(from); dn; dn = of_find_all_nodes(dn)) +#define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn) + +/* Dummy functions to mirror Linux. These are not used in U-Boot */ +#define of_node_get(x) (x) +static inline void of_node_put(const struct device_node *np) { } + +/** + * of_n_addr_cells() - Get the number of address cells for a node + * + * This walks back up the tree to find the closest #address-cells property + * which controls the given node. + * + * @np: Node pointer to check + * @return number of address cells this node uses + */ +int of_n_addr_cells(const struct device_node *np); + +/** + * of_n_size_cells() - Get the number of size cells for a node + * + * This walks back up the tree to find the closest #size-cells property + * which controls the given node. + * + * @np: Node pointer to check + * @return number of size cells this node uses + */ +int of_n_size_cells(const struct device_node *np); + +/** + * of_simple_addr_cells() - Get the address cells property in a node + * + * This function matches fdt_address_cells(). + * + * @np: Node pointer to check + * @return value of #address-cells property in this node, or 2 if none + */ +int of_simple_addr_cells(const struct device_node *np); + +/** + * of_simple_size_cells() - Get the size cells property in a node + * + * This function matches fdt_size_cells(). + * + * @np: Node pointer to check + * @return value of #size-cells property in this node, or 2 if none + */ +int of_simple_size_cells(const struct device_node *np); + +/** + * of_find_property() - find a property in a node + * + * @np: Pointer to device node holding property + * @name: Name of property + * @lenp: If non-NULL, returns length of property + * @return pointer to property, or NULL if not found + */ +struct property *of_find_property(const struct device_node *np, + const char *name, int *lenp); + +/** + * of_get_property() - get a property value + * + * Find a property with a given name for a given node and return the value. + * + * @np: Pointer to device node holding property + * @name: Name of property + * @lenp: If non-NULL, returns length of property + * @return pointer to property value, or NULL if not found + */ +const void *of_get_property(const struct device_node *np, const char *name, + int *lenp); + +/** + * of_device_is_compatible() - Check if the node matches given constraints + * @device: pointer to node + * @compat: required compatible string, NULL or "" for any match + * @type: required device_type value, NULL or "" for any match + * @name: required node name, NULL or "" for any match + * + * Checks if the given @compat, @type and @name strings match the + * properties of the given @device. A constraints can be skipped by + * passing NULL or an empty string as the constraint. + * + * @return 0 for no match, and a positive integer on match. The return + * value is a relative score with larger values indicating better + * matches. The score is weighted for the most specific compatible value + * to get the highest score. Matching type is next, followed by matching + * name. Practically speaking, this results in the following priority + * order for matches: + * + * 1. specific compatible && type && name + * 2. specific compatible && type + * 3. specific compatible && name + * 4. specific compatible + * 5. general compatible && type && name + * 6. general compatible && type + * 7. general compatible && name + * 8. general compatible + * 9. type && name + * 10. type + * 11. name + */ +int of_device_is_compatible(const struct device_node *np, const char *compat, + const char *type, const char *name); + +/** + * of_device_is_available() - check if a device is available for use + * + * @device: Node to check for availability + * + * @return true if the status property is absent or set to "okay", false + * otherwise + */ +bool of_device_is_available(const struct device_node *np); + +/** + * of_get_parent() - Get a node's parent, if any + * + * @node: Node to check + * @eturns a node pointer, or NULL if none + */ +struct device_node *of_get_parent(const struct device_node *np); + +/** + * of_find_node_opts_by_path() - Find a node matching a full OF path + * + * @path: Either the full path to match, or if the path does not start with + * '/', the name of a property of the /aliases node (an alias). In the + * case of an alias, the node matching the alias' value will be returned. + * @opts: Address of a pointer into which to store the start of an options + * string appended to the end of the path with a ':' separator. Can be NULL + * + * Valid paths: + * /foo/bar Full path + * foo Valid alias + * foo/bar Valid alias + relative path + * + * @return a node pointer or NULL if not found + */ +struct device_node *of_find_node_opts_by_path(const char *path, + const char **opts); + +static inline struct device_node *of_find_node_by_path(const char *path) +{ + return of_find_node_opts_by_path(path, NULL); +} + +/** + * of_find_compatible_node() - find a node based on its compatible string + * + * Find a node based on type and one of the tokens in its "compatible" property + * @from: Node to start searching from or NULL. the node you pass will not be + * searched, only the next one will; typically, you pass what the previous + * call returned. + * @type: The type string to match "device_type" or NULL to ignore + * @compatible: The string to match to one of the tokens in the device + * "compatible" list. + * @return node pointer or NULL if not found + */ +struct device_node *of_find_compatible_node(struct device_node *from, + const char *type, const char *compatible); + +/** + * of_find_node_by_prop_value() - find a node with a given property value + * + * Find a node based on a property value. + * @from: Node to start searching from or NULL. the node you pass will not be + * searched, only the next one will; typically, you pass what the previous + * call returned. + * @propname: property name to check + * @propval: property value to search for + * @proplen: length of the value in propval + * @return node pointer or NULL if not found + */ +struct device_node *of_find_node_by_prop_value(struct device_node *from, + const char *propname, + const void *propval, + int proplen); +/** + * of_find_node_by_phandle() - Find a node given a phandle + * + * @handle: phandle of the node to find + * + * @return node pointer, or NULL if not found + */ +struct device_node *of_find_node_by_phandle(phandle handle); + +/** + * of_read_u32() - Find and read a 32-bit integer from a property + * + * Search for a property in a device node and read a 32-bit value from + * it. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @outp: pointer to return value, modified only if return value is 0. + * + * @return 0 on success, -EINVAL if the property does not exist, + * -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data isn't large enough. + */ +int of_read_u32(const struct device_node *np, const char *propname, u32 *outp); + +/** + * of_read_u64() - Find and read a 64-bit integer from a property + * + * Search for a property in a device node and read a 64-bit value from + * it. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @outp: pointer to return value, modified only if return value is 0. + * + * @return 0 on success, -EINVAL if the property does not exist, + * -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data isn't large enough. + */ +int of_read_u64(const struct device_node *np, const char *propname, u64 *outp); + +/** + * of_read_u32_array() - Find and read an array of 32 bit integers + * + * Search for a property in a device node and read 32-bit value(s) from + * it. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_values: pointer to return value, modified only if return value is 0. + * @sz: number of array elements to read + * @return 0 on success, -EINVAL if the property does not exist, -ENODATA + * if property does not have a value, and -EOVERFLOW is longer than sz. + */ +int of_read_u32_array(const struct device_node *np, const char *propname, + u32 *out_values, size_t sz); + +/** + * of_property_match_string() - Find string in a list and return index + * + * This function searches a string list property and returns the index + * of a specific string value. + * + * @np: pointer to node containing string list property + * @propname: string list property name + * @string: pointer to string to search for in string list + * @return 0 on success, -EINVAL if the property does not exist, -ENODATA + * if property does not have a value, and -EOVERFLOW is longer than sz. + */ +int of_property_match_string(const struct device_node *np, const char *propname, + const char *string); + +int of_property_read_string_helper(const struct device_node *np, + const char *propname, const char **out_strs, + size_t sz, int index); + +/** + * of_property_read_string_index() - Find and read a string from a multiple + * strings property. + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @index: index of the string in the list of strings + * @out_string: pointer to null terminated return string, modified only if + * return value is 0. + * + * Search for a property in a device tree node and retrieve a null + * terminated string value (pointer to data, not a copy) in the list of strings + * contained in that property. + * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if + * property does not have a value, and -EILSEQ if the string is not + * null-terminated within the length of the property data. + * + * The out_string pointer is modified only if a valid string can be decoded. + */ +static inline int of_property_read_string_index(const struct device_node *np, + const char *propname, + int index, const char **output) +{ + int rc = of_property_read_string_helper(np, propname, output, 1, index); + return rc < 0 ? rc : 0; +} + +/** + * of_property_count_strings() - Find and return the number of strings from a + * multiple strings property. + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * + * Search for a property in a device tree node and retrieve the number of null + * terminated string contain in it. Returns the number of strings on + * success, -EINVAL if the property does not exist, -ENODATA if property + * does not have a value, and -EILSEQ if the string is not null-terminated + * within the length of the property data. + */ +static inline int of_property_count_strings(const struct device_node *np, + const char *propname) +{ + return of_property_read_string_helper(np, propname, NULL, 0, 0); +} + +/** + * of_parse_phandle - Resolve a phandle property to a device_node pointer + * @np: Pointer to device node holding phandle property + * @phandle_name: Name of property holding a phandle value + * @index: For properties holding a table of phandles, this is the index into + * the table + * + * Returns the device_node pointer with refcount incremented. Use + * of_node_put() on it when done. + */ +struct device_node *of_parse_phandle(const struct device_node *np, + const char *phandle_name, int index); + +/** + * of_parse_phandle_with_args() - Find a node pointed by phandle in a list + * + * @np: pointer to a device tree node containing a list + * @list_name: property name that contains a list + * @cells_name: property name that specifies phandles' arguments count + * @index: index of a phandle to parse out + * @out_args: optional pointer to output arguments structure (will be filled) + * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if + * @list_name does not exist, -EINVAL if a phandle was not found, + * @cells_name could not be found, the arguments were truncated or there + * were too many arguments. + * + * This function is useful to parse lists of phandles and their arguments. + * Returns 0 on success and fills out_args, on error returns appropriate + * errno value. + * + * Caller is responsible to call of_node_put() on the returned out_args->np + * pointer. + * + * Example: + * + * phandle1: node1 { + * #list-cells = <2>; + * } + * + * phandle2: node2 { + * #list-cells = <1>; + * } + * + * node3 { + * list = <&phandle1 1 2 &phandle2 3>; + * } + * + * To get a device_node of the `node2' node you may call this: + * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args); + */ +int of_parse_phandle_with_args(const struct device_node *np, + const char *list_name, const char *cells_name, + int index, struct of_phandle_args *out_args); + +/** + * of_count_phandle_with_args() - Count the number of phandle in a list + * + * @np: pointer to a device tree node containing a list + * @list_name: property name that contains a list + * @cells_name: property name that specifies phandles' arguments count + * @return number of phandle found, -ENOENT if + * @list_name does not exist, -EINVAL if a phandle was not found, + * @cells_name could not be found, the arguments were truncated or there + * were too many arguments. + * + * Returns number of phandle found on success, on error returns appropriate + * errno value. + * + */ +int of_count_phandle_with_args(const struct device_node *np, + const char *list_name, const char *cells_name); + +/** + * of_alias_scan() - Scan all properties of the 'aliases' node + * + * The function scans all the properties of the 'aliases' node and populates + * the lookup table with the properties. It returns the number of alias + * properties found, or an error code in case of failure. + * + * @return 9 if OK, -ENOMEM if not enough memory + */ +int of_alias_scan(void); + +/** + * of_alias_get_id - Get alias id for the given device_node + * + * Travels the lookup table to get the alias id for the given device_node and + * alias stem. + * + * @np: Pointer to the given device_node + * @stem: Alias stem of the given device_node + * @return alias ID, if found, else -ENODEV + */ +int of_alias_get_id(const struct device_node *np, const char *stem); + +/** + * of_alias_get_highest_id - Get highest alias id for the given stem + * @stem: Alias stem to be examined + * + * The function travels the lookup table to get the highest alias id for the + * given alias stem. + * @return alias ID, if found, else -1 + */ +int of_alias_get_highest_id(const char *stem); + +/** + * of_get_stdout() - Get node to use for stdout + * + * @return node referred to by stdout-path alias, or NULL if none + */ +struct device_node *of_get_stdout(void); + +#endif |