u-boot/include/dm/of_access.h
Michal Simek 5ebc7c7e27 dm: core: Add of_alias_get_highest_id()
The same functionality was added to Linux for i2c bus registration with this
commit message:

"
of: base: add function to get highest id of an alias stem

I2C supports adding adapters using either a dynamic or fixed id. The
latter is provided by aliases in the DT case. To prevent id collisions
of those two types, install this function which gives us the highest
fixed id, so we can then let the dynamically created ones come after
this highest number.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
"

Add it also to U-Boot for DM I2C support.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
2019-02-08 06:24:57 +01:00

444 lines
15 KiB
C

/* 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