blob: e851c57a15b066cd365765b309a739f9a398e22d [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* drivers/of/property.c - Procedures for accessing and interpreting
* Devicetree properties and graphs.
*
* Initially created by copying procedures from drivers/of/base.c. This
* file contains the OF property as well as the OF graph interface
* functions.
*
* Paul Mackerras August 1996.
* Copyright (C) 1996-2005 Paul Mackerras.
*
* Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
* {engebret|bergner}@us.ibm.com
*
* Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net
*
* Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and
* Grant Likely.
*/
#define pr_fmt(fmt) "OF: " fmt
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_graph.h>
#include <linux/string.h>
#include <linux/moduleparam.h>
#include "of_private.h"
/**
* of_property_count_elems_of_size - Count the number of elements in a property
*
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @elem_size: size of the individual element
*
* Search for a property in a device node and count the number of elements of
* size elem_size in it. Returns number of elements on sucess, -EINVAL if the
* property does not exist or its length does not match a multiple of elem_size
* and -ENODATA if the property does not have a value.
*/
int of_property_count_elems_of_size(const struct device_node *np,
const char *propname, int elem_size)
{
struct property *prop = of_find_property(np, propname, NULL);
if (!prop)
return -EINVAL;
if (!prop->value)
return -ENODATA;
if (prop->length % elem_size != 0) {
pr_err("size of %s in node %pOF is not a multiple of %d\n",
propname, np, elem_size);
return -EINVAL;
}
return prop->length / elem_size;
}
EXPORT_SYMBOL_GPL(of_property_count_elems_of_size);
/**
* of_find_property_value_of_size
*
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @min: minimum allowed length of property value
* @max: maximum allowed length of property value (0 means unlimited)
* @len: if !=NULL, actual length is written to here
*
* Search for a property in a device node and valid the requested size.
* Returns the property value on success, -EINVAL if the property does not
* exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
* property data is too small or too large.
*
*/
static void *of_find_property_value_of_size(const struct device_node *np,
const char *propname, u32 min, u32 max, size_t *len)
{
struct property *prop = of_find_property(np, propname, NULL);
if (!prop)
return ERR_PTR(-EINVAL);
if (!prop->value)
return ERR_PTR(-ENODATA);
if (prop->length < min)
return ERR_PTR(-EOVERFLOW);
if (max && prop->length > max)
return ERR_PTR(-EOVERFLOW);
if (len)
*len = prop->length;
return prop->value;
}
/**
* of_property_read_u32_index - Find and read a u32 from a multi-value 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 u32 in the list of values
* @out_value: pointer to return value, modified only if no error.
*
* Search for a property in a device node and read nth 32-bit value from
* it. Returns 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.
*
* The out_value is modified only if a valid u32 value can be decoded.
*/
int of_property_read_u32_index(const struct device_node *np,
const char *propname,
u32 index, u32 *out_value)
{
const u32 *val = of_find_property_value_of_size(np, propname,
((index + 1) * sizeof(*out_value)),
0,
NULL);
if (IS_ERR(val))
return PTR_ERR(val);
*out_value = be32_to_cpup(((__be32 *)val) + index);
return 0;
}
EXPORT_SYMBOL_GPL(of_property_read_u32_index);
/**
* of_property_read_u64_index - Find and read a u64 from a multi-value 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 u64 in the list of values
* @out_value: pointer to return value, modified only if no error.
*
* Search for a property in a device node and read nth 64-bit value from
* it. Returns 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.
*
* The out_value is modified only if a valid u64 value can be decoded.
*/
int of_property_read_u64_index(const struct device_node *np,
const char *propname,
u32 index, u64 *out_value)
{
const u64 *val = of_find_property_value_of_size(np, propname,
((index + 1) * sizeof(*out_value)),
0, NULL);
if (IS_ERR(val))
return PTR_ERR(val);
*out_value = be64_to_cpup(((__be64 *)val) + index);
return 0;
}
EXPORT_SYMBOL_GPL(of_property_read_u64_index);
/**
* of_property_read_variable_u8_array - Find and read an array of u8 from a
* property, with bounds on the minimum and maximum array size.
*
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @out_values: pointer to found values.
* @sz_min: minimum number of array elements to read
* @sz_max: maximum number of array elements to read, if zero there is no
* upper limit on the number of elements in the dts entry but only
* sz_min will be read.
*
* Search for a property in a device node and read 8-bit value(s) from
* it. Returns number of elements read on success, -EINVAL if the property
* does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
* if the property data is smaller than sz_min or longer than sz_max.
*
* dts entry of array should be like:
* property = /bits/ 8 <0x50 0x60 0x70>;
*
* The out_values is modified only if a valid u8 value can be decoded.
*/
int of_property_read_variable_u8_array(const struct device_node *np,
const char *propname, u8 *out_values,
size_t sz_min, size_t sz_max)
{
size_t sz, count;
const u8 *val = of_find_property_value_of_size(np, propname,
(sz_min * sizeof(*out_values)),
(sz_max * sizeof(*out_values)),
&sz);
if (IS_ERR(val))
return PTR_ERR(val);
if (!sz_max)
sz = sz_min;
else
sz /= sizeof(*out_values);
count = sz;
while (count--)
*out_values++ = *val++;
return sz;
}
EXPORT_SYMBOL_GPL(of_property_read_variable_u8_array);
/**
* of_property_read_variable_u16_array - Find and read an array of u16 from a
* property, with bounds on the minimum and maximum array size.
*
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @out_values: pointer to found values.
* @sz_min: minimum number of array elements to read
* @sz_max: maximum number of array elements to read, if zero there is no
* upper limit on the number of elements in the dts entry but only
* sz_min will be read.
*
* Search for a property in a device node and read 16-bit value(s) from
* it. Returns number of elements read on success, -EINVAL if the property
* does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
* if the property data is smaller than sz_min or longer than sz_max.
*
* dts entry of array should be like:
* property = /bits/ 16 <0x5000 0x6000 0x7000>;
*
* The out_values is modified only if a valid u16 value can be decoded.
*/
int of_property_read_variable_u16_array(const struct device_node *np,
const char *propname, u16 *out_values,
size_t sz_min, size_t sz_max)
{
size_t sz, count;
const __be16 *val = of_find_property_value_of_size(np, propname,
(sz_min * sizeof(*out_values)),
(sz_max * sizeof(*out_values)),
&sz);
if (IS_ERR(val))
return PTR_ERR(val);
if (!sz_max)
sz = sz_min;
else
sz /= sizeof(*out_values);
count = sz;
while (count--)
*out_values++ = be16_to_cpup(val++);
return sz;
}
EXPORT_SYMBOL_GPL(of_property_read_variable_u16_array);
/**
* of_property_read_variable_u32_array - Find and read an array of 32 bit
* integers from a property, with bounds on the minimum and maximum array size.
*
* @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 found values.
* @sz_min: minimum number of array elements to read
* @sz_max: maximum number of array elements to read, if zero there is no
* upper limit on the number of elements in the dts entry but only
* sz_min will be read.
*
* Search for a property in a device node and read 32-bit value(s) from
* it. Returns number of elements read on success, -EINVAL if the property
* does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
* if the property data is smaller than sz_min or longer than sz_max.
*
* The out_values is modified only if a valid u32 value can be decoded.
*/
int of_property_read_variable_u32_array(const struct device_node *np,
const char *propname, u32 *out_values,
size_t sz_min, size_t sz_max)
{
size_t sz, count;
const __be32 *val = of_find_property_value_of_size(np, propname,
(sz_min * sizeof(*out_values)),
(sz_max * sizeof(*out_values)),
&sz);
if (IS_ERR(val))
return PTR_ERR(val);
if (!sz_max)
sz = sz_min;
else
sz /= sizeof(*out_values);
count = sz;
while (count--)
*out_values++ = be32_to_cpup(val++);
return sz;
}
EXPORT_SYMBOL_GPL(of_property_read_variable_u32_array);
/**
* of_property_read_u64 - Find and read a 64 bit integer from a property
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @out_value: pointer to return value, modified only if return value is 0.
*
* Search for a property in a device node and read a 64-bit value from
* it. Returns 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.
*
* The out_value is modified only if a valid u64 value can be decoded.
*/
int of_property_read_u64(const struct device_node *np, const char *propname,
u64 *out_value)
{
const __be32 *val = of_find_property_value_of_size(np, propname,
sizeof(*out_value),
0,
NULL);
if (IS_ERR(val))
return PTR_ERR(val);
*out_value = of_read_number(val, 2);
return 0;
}
EXPORT_SYMBOL_GPL(of_property_read_u64);
/**
* of_property_read_variable_u64_array - Find and read an array of 64 bit
* integers from a property, with bounds on the minimum and maximum array size.
*
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @out_values: pointer to found values.
* @sz_min: minimum number of array elements to read
* @sz_max: maximum number of array elements to read, if zero there is no
* upper limit on the number of elements in the dts entry but only
* sz_min will be read.
*
* Search for a property in a device node and read 64-bit value(s) from
* it. Returns number of elements read on success, -EINVAL if the property
* does not exist, -ENODATA if property does not have a value, and -EOVERFLOW
* if the property data is smaller than sz_min or longer than sz_max.
*
* The out_values is modified only if a valid u64 value can be decoded.
*/
int of_property_read_variable_u64_array(const struct device_node *np,
const char *propname, u64 *out_values,
size_t sz_min, size_t sz_max)
{
size_t sz, count;
const __be32 *val = of_find_property_value_of_size(np, propname,
(sz_min * sizeof(*out_values)),
(sz_max * sizeof(*out_values)),
&sz);
if (IS_ERR(val))
return PTR_ERR(val);
if (!sz_max)
sz = sz_min;
else
sz /= sizeof(*out_values);
count = sz;
while (count--) {
*out_values++ = of_read_number(val, 2);
val += 2;
}
return sz;
}
EXPORT_SYMBOL_GPL(of_property_read_variable_u64_array);
/**
* of_property_read_string - Find and read a string from a property
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @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). 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.
*/
int of_property_read_string(const struct device_node *np, const char *propname,
const char **out_string)
{
const struct property *prop = of_find_property(np, propname, NULL);
if (!prop)
return -EINVAL;
if (!prop->value)
return -ENODATA;
if (strnlen(prop->value, prop->length) >= prop->length)
return -EILSEQ;
*out_string = prop->value;
return 0;
}
EXPORT_SYMBOL_GPL(of_property_read_string);
/**
* of_property_match_string() - Find string in a list and return index
* @np: pointer to node containing string list property
* @propname: string list property name
* @string: pointer to string to search for in string list
*
* This function searches a string list property and returns the index
* of a specific string value.
*/
int of_property_match_string(const struct device_node *np, const char *propname,
const char *string)
{
const struct property *prop = of_find_property(np, propname, NULL);
size_t l;
int i;
const char *p, *end;
if (!prop)
return -EINVAL;
if (!prop->value)
return -ENODATA;
p = prop->value;
end = p + prop->length;
for (i = 0; p < end; i++, p += l) {
l = strnlen(p, end - p) + 1;
if (p + l > end)
return -EILSEQ;
pr_debug("comparing %s with %s\n", string, p);
if (strcmp(string, p) == 0)
return i; /* Found it; return index */
}
return -ENODATA;
}
EXPORT_SYMBOL_GPL(of_property_match_string);
/**
* of_property_read_string_helper() - Utility helper for parsing string properties
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @out_strs: output array of string pointers.
* @sz: number of array elements to read.
* @skip: Number of strings to skip over at beginning of list.
*
* Don't call this function directly. It is a utility helper for the
* of_property_read_string*() family of functions.
*/
int of_property_read_string_helper(const struct device_node *np,
const char *propname, const char **out_strs,
size_t sz, int skip)
{
const struct property *prop = of_find_property(np, propname, NULL);
int l = 0, i = 0;
const char *p, *end;
if (!prop)
return -EINVAL;
if (!prop->value)
return -ENODATA;
p = prop->value;
end = p + prop->length;
for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) {
l = strnlen(p, end - p) + 1;
if (p + l > end)
return -EILSEQ;
if (out_strs && i >= skip)
*out_strs++ = p;
}
i -= skip;
return i <= 0 ? -ENODATA : i;
}
EXPORT_SYMBOL_GPL(of_property_read_string_helper);
const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
u32 *pu)
{
const void *curv = cur;
if (!prop)
return NULL;
if (!cur) {
curv = prop->value;
goto out_val;
}
curv += sizeof(*cur);
if (curv >= prop->value + prop->length)
return NULL;
out_val:
*pu = be32_to_cpup(curv);
return curv;
}
EXPORT_SYMBOL_GPL(of_prop_next_u32);
const char *of_prop_next_string(struct property *prop, const char *cur)
{
const void *curv = cur;
if (!prop)
return NULL;
if (!cur)
return prop->value;
curv += strlen(cur) + 1;
if (curv >= prop->value + prop->length)
return NULL;
return curv;
}
EXPORT_SYMBOL_GPL(of_prop_next_string);
/**
* of_graph_parse_endpoint() - parse common endpoint node properties
* @node: pointer to endpoint device_node
* @endpoint: pointer to the OF endpoint data structure
*
* The caller should hold a reference to @node.
*/
int of_graph_parse_endpoint(const struct device_node *node,
struct of_endpoint *endpoint)
{
struct device_node *port_node = of_get_parent(node);
WARN_ONCE(!port_node, "%s(): endpoint %pOF has no parent node\n",
__func__, node);
memset(endpoint, 0, sizeof(*endpoint));
endpoint->local_node = node;
/*
* It doesn't matter whether the two calls below succeed.
* If they don't then the default value 0 is used.
*/
of_property_read_u32(port_node, "reg", &endpoint->port);
of_property_read_u32(node, "reg", &endpoint->id);
of_node_put(port_node);
return 0;
}
EXPORT_SYMBOL(of_graph_parse_endpoint);
/**
* of_graph_get_port_by_id() - get the port matching a given id
* @parent: pointer to the parent device node
* @id: id of the port
*
* Return: A 'port' node pointer with refcount incremented. The caller
* has to use of_node_put() on it when done.
*/
struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id)
{
struct device_node *node, *port;
node = of_get_child_by_name(parent, "ports");
if (node)
parent = node;
for_each_child_of_node(parent, port) {
u32 port_id = 0;
if (!of_node_name_eq(port, "port"))
continue;
of_property_read_u32(port, "reg", &port_id);
if (id == port_id)
break;
}
of_node_put(node);
return port;
}
EXPORT_SYMBOL(of_graph_get_port_by_id);
/**
* of_graph_get_next_endpoint() - get next endpoint node
* @parent: pointer to the parent device node
* @prev: previous endpoint node, or NULL to get first
*
* Return: An 'endpoint' node pointer with refcount incremented. Refcount
* of the passed @prev node is decremented.
*/
struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
struct device_node *prev)
{
struct device_node *endpoint;
struct device_node *port;
if (!parent)
return NULL;
/*
* Start by locating the port node. If no previous endpoint is specified
* search for the first port node, otherwise get the previous endpoint
* parent port node.
*/
if (!prev) {
struct device_node *node;
node = of_get_child_by_name(parent, "ports");
if (node)
parent = node;
port = of_get_child_by_name(parent, "port");
of_node_put(node);
if (!port) {
pr_err("graph: no port node found in %pOF\n", parent);
return NULL;
}
} else {
port = of_get_parent(prev);
if (WARN_ONCE(!port, "%s(): endpoint %pOF has no parent node\n",
__func__, prev))
return NULL;
}
while (1) {
/*
* Now that we have a port node, get the next endpoint by
* getting the next child. If the previous endpoint is NULL this
* will return the first child.
*/
endpoint = of_get_next_child(port, prev);
if (endpoint) {
of_node_put(port);
return endpoint;
}
/* No more endpoints under this port, try the next one. */
prev = NULL;
do {
port = of_get_next_child(parent, port);
if (!port)
return NULL;
} while (!of_node_name_eq(port, "port"));
}
}
EXPORT_SYMBOL(of_graph_get_next_endpoint);
/**
* of_graph_get_endpoint_by_regs() - get endpoint node of specific identifiers
* @parent: pointer to the parent device node
* @port_reg: identifier (value of reg property) of the parent port node
* @reg: identifier (value of reg property) of the endpoint node
*
* Return: An 'endpoint' node pointer which is identified by reg and at the same
* is the child of a port node identified by port_reg. reg and port_reg are
* ignored when they are -1. Use of_node_put() on the pointer when done.
*/
struct device_node *of_graph_get_endpoint_by_regs(
const struct device_node *parent, int port_reg, int reg)
{
struct of_endpoint endpoint;
struct device_node *node = NULL;
for_each_endpoint_of_node(parent, node) {
of_graph_parse_endpoint(node, &endpoint);
if (((port_reg == -1) || (endpoint.port == port_reg)) &&
((reg == -1) || (endpoint.id == reg)))
return node;
}
return NULL;
}
EXPORT_SYMBOL(of_graph_get_endpoint_by_regs);
/**
* of_graph_get_remote_endpoint() - get remote endpoint node
* @node: pointer to a local endpoint device_node
*
* Return: Remote endpoint node associated with remote endpoint node linked
* to @node. Use of_node_put() on it when done.
*/
struct device_node *of_graph_get_remote_endpoint(const struct device_node *node)
{
/* Get remote endpoint node. */
return of_parse_phandle(node, "remote-endpoint", 0);
}
EXPORT_SYMBOL(of_graph_get_remote_endpoint);
/**
* of_graph_get_port_parent() - get port's parent node
* @node: pointer to a local endpoint device_node
*
* Return: device node associated with endpoint node linked
* to @node. Use of_node_put() on it when done.
*/
struct device_node *of_graph_get_port_parent(struct device_node *node)
{
unsigned int depth;
if (!node)
return NULL;
/*
* Preserve usecount for passed in node as of_get_next_parent()
* will do of_node_put() on it.
*/
of_node_get(node);
/* Walk 3 levels up only if there is 'ports' node. */
for (depth = 3; depth && node; depth--) {
node = of_get_next_parent(node);
if (depth == 2 && !of_node_name_eq(node, "ports"))
break;
}
return node;
}
EXPORT_SYMBOL(of_graph_get_port_parent);
/**
* of_graph_get_remote_port_parent() - get remote port's parent node
* @node: pointer to a local endpoint device_node
*
* Return: Remote device node associated with remote endpoint node linked
* to @node. Use of_node_put() on it when done.
*/
struct device_node *of_graph_get_remote_port_parent(
const struct device_node *node)
{
struct device_node *np, *pp;
/* Get remote endpoint node. */
np = of_graph_get_remote_endpoint(node);
pp = of_graph_get_port_parent(np);
of_node_put(np);
return pp;
}
EXPORT_SYMBOL(of_graph_get_remote_port_parent);
/**
* of_graph_get_remote_port() - get remote port node
* @node: pointer to a local endpoint device_node
*
* Return: Remote port node associated with remote endpoint node linked
* to @node. Use of_node_put() on it when done.
*/
struct device_node *of_graph_get_remote_port(const struct device_node *node)
{
struct device_node *np;
/* Get remote endpoint node. */
np = of_graph_get_remote_endpoint(node);
if (!np)
return NULL;
return of_get_next_parent(np);
}
EXPORT_SYMBOL(of_graph_get_remote_port);
int of_graph_get_endpoint_count(const struct device_node *np)
{
struct device_node *endpoint;
int num = 0;
for_each_endpoint_of_node(np, endpoint)
num++;
return num;
}
EXPORT_SYMBOL(of_graph_get_endpoint_count);
/**
* of_graph_get_remote_node() - get remote parent device_node for given port/endpoint
* @node: pointer to parent device_node containing graph port/endpoint
* @port: identifier (value of reg property) of the parent port node
* @endpoint: identifier (value of reg property) of the endpoint node
*
* Return: Remote device node associated with remote endpoint node linked
* to @node. Use of_node_put() on it when done.
*/
struct device_node *of_graph_get_remote_node(const struct device_node *node,
u32 port, u32 endpoint)
{
struct device_node *endpoint_node, *remote;
endpoint_node = of_graph_get_endpoint_by_regs(node, port, endpoint);
if (!endpoint_node) {
pr_debug("no valid endpoint (%d, %d) for node %pOF\n",
port, endpoint, node);
return NULL;
}
remote = of_graph_get_remote_port_parent(endpoint_node);
of_node_put(endpoint_node);
if (!remote) {
pr_debug("no valid remote node\n");
return NULL;
}
if (!of_device_is_available(remote)) {
pr_debug("not available for remote node\n");
of_node_put(remote);
return NULL;
}
return remote;
}
EXPORT_SYMBOL(of_graph_get_remote_node);
static struct fwnode_handle *of_fwnode_get(struct fwnode_handle *fwnode)
{
return of_fwnode_handle(of_node_get(to_of_node(fwnode)));
}
static void of_fwnode_put(struct fwnode_handle *fwnode)
{
of_node_put(to_of_node(fwnode));
}
static bool of_fwnode_device_is_available(const struct fwnode_handle *fwnode)
{
return of_device_is_available(to_of_node(fwnode));
}
static bool of_fwnode_property_present(const struct fwnode_handle *fwnode,
const char *propname)
{
return of_property_read_bool(to_of_node(fwnode), propname);
}
static int of_fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
const char *propname,
unsigned int elem_size, void *val,
size_t nval)
{
const struct device_node *node = to_of_node(fwnode);
if (!val)
return of_property_count_elems_of_size(node, propname,
elem_size);
switch (elem_size) {
case sizeof(u8):
return of_property_read_u8_array(node, propname, val, nval);
case sizeof(u16):
return of_property_read_u16_array(node, propname, val, nval);
case sizeof(u32):
return of_property_read_u32_array(node, propname, val, nval);
case sizeof(u64):
return of_property_read_u64_array(node, propname, val, nval);
}
return -ENXIO;
}
static int
of_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
const char *propname, const char **val,
size_t nval)
{
const struct device_node *node = to_of_node(fwnode);
return val ?
of_property_read_string_array(node, propname, val, nval) :
of_property_count_strings(node, propname);
}
static const char *of_fwnode_get_name(const struct fwnode_handle *fwnode)
{
return kbasename(to_of_node(fwnode)->full_name);
}
static const char *of_fwnode_get_name_prefix(const struct fwnode_handle *fwnode)
{
/* Root needs no prefix here (its name is "/"). */
if (!to_of_node(fwnode)->parent)
return "";
return "/";
}
static struct fwnode_handle *
of_fwnode_get_parent(const struct fwnode_handle *fwnode)
{
return of_fwnode_handle(of_get_parent(to_of_node(fwnode)));
}
static struct fwnode_handle *
of_fwnode_get_next_child_node(const struct fwnode_handle *fwnode,
struct fwnode_handle *child)
{
return of_fwnode_handle(of_get_next_available_child(to_of_node(fwnode),
to_of_node(child)));
}
static struct fwnode_handle *
of_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
const char *childname)
{
const struct device_node *node = to_of_node(fwnode);
struct device_node *child;
for_each_available_child_of_node(node, child)
if (of_node_name_eq(child, childname))
return of_fwnode_handle(child);
return NULL;
}
static int
of_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
const char *prop, const char *nargs_prop,
unsigned int nargs, unsigned int index,
struct fwnode_reference_args *args)
{
struct of_phandle_args of_args;
unsigned int i;
int ret;
if (nargs_prop)
ret = of_parse_phandle_with_args(to_of_node(fwnode), prop,
nargs_prop, index, &of_args);
else
ret = of_parse_phandle_with_fixed_args(to_of_node(fwnode), prop,
nargs, index, &of_args);
if (ret < 0)
return ret;
if (!args)
return 0;
args->nargs = of_args.args_count;
args->fwnode = of_fwnode_handle(of_args.np);
for (i = 0; i < NR_FWNODE_REFERENCE_ARGS; i++)
args->args[i] = i < of_args.args_count ? of_args.args[i] : 0;
return 0;
}
static struct fwnode_handle *
of_fwnode_graph_get_next_endpoint(const struct fwnode_handle *fwnode,
struct fwnode_handle *prev)
{
return of_fwnode_handle(of_graph_get_next_endpoint(to_of_node(fwnode),
to_of_node(prev)));
}
static struct fwnode_handle *
of_fwnode_graph_get_remote_endpoint(const struct fwnode_handle *fwnode)
{
return of_fwnode_handle(
of_graph_get_remote_endpoint(to_of_node(fwnode)));
}
static struct fwnode_handle *
of_fwnode_graph_get_port_parent(struct fwnode_handle *fwnode)
{
struct device_node *np;
/* Get the parent of the port */
np = of_get_parent(to_of_node(fwnode));
if (!np)
return NULL;
/* Is this the "ports" node? If not, it's the port parent. */
if (!of_node_name_eq(np, "ports"))
return of_fwnode_handle(np);
return of_fwnode_handle(of_get_next_parent(np));
}
static int of_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
struct fwnode_endpoint *endpoint)
{
const struct device_node *node = to_of_node(fwnode);
struct device_node *port_node = of_get_parent(node);
endpoint->local_fwnode = fwnode;
of_property_read_u32(port_node, "reg", &endpoint->port);
of_property_read_u32(node, "reg", &endpoint->id);
of_node_put(port_node);
return 0;
}
static const void *
of_fwnode_device_get_match_data(const struct fwnode_handle *fwnode,
const struct device *dev)
{
return of_device_get_match_data(dev);
}
static bool of_is_ancestor_of(struct device_node *test_ancestor,
struct device_node *child)
{
of_node_get(child);
while (child) {
if (child == test_ancestor) {
of_node_put(child);
return true;
}
child = of_get_next_parent(child);
}
return false;
}
/**
* of_link_to_phandle - Add device link to supplier from supplier phandle
* @dev: consumer device
* @sup_np: phandle to supplier device tree node
*
* Given a phandle to a supplier device tree node (@sup_np), this function
* finds the device that owns the supplier device tree node and creates a
* device link from @dev consumer device to the supplier device. This function
* doesn't create device links for invalid scenarios such as trying to create a
* link with a parent device as the consumer of its child device. In such
* cases, it returns an error.
*
* Returns:
* - 0 if link successfully created to supplier
* - -EAGAIN if linking to the supplier should be reattempted
* - -EINVAL if the supplier link is invalid and should not be created
* - -ENODEV if there is no device that corresponds to the supplier phandle
*/
static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,
u32 dl_flags)
{
struct device *sup_dev;
int ret = 0;
struct device_node *tmp_np = sup_np;
int is_populated;
of_node_get(sup_np);
/*
* Find the device node that contains the supplier phandle. It may be
* @sup_np or it may be an ancestor of @sup_np.
*/
while (sup_np && !of_find_property(sup_np, "compatible", NULL))
sup_np = of_get_next_parent(sup_np);
if (!sup_np) {
dev_dbg(dev, "Not linking to %pOFP - No device\n", tmp_np);
return -ENODEV;
}
/*
* Don't allow linking a device node as a consumer of one of its
* descendant nodes. By definition, a child node can't be a functional
* dependency for the parent node.
*/
if (of_is_ancestor_of(dev->of_node, sup_np)) {
dev_dbg(dev, "Not linking to %pOFP - is descendant\n", sup_np);
of_node_put(sup_np);
return -EINVAL;
}
sup_dev = get_dev_from_fwnode(&sup_np->fwnode);
is_populated = of_node_check_flag(sup_np, OF_POPULATED);
of_node_put(sup_np);
if (!sup_dev && is_populated) {
/* Early device without struct device. */
dev_dbg(dev, "Not linking to %pOFP - No struct device\n",
sup_np);
return -ENODEV;
} else if (!sup_dev) {
return -EAGAIN;
}
if (!device_link_add(dev, sup_dev, dl_flags))
ret = -EAGAIN;
put_device(sup_dev);
return ret;
}
/**
* parse_prop_cells - Property parsing function for suppliers
*
* @np: Pointer to device tree node containing a list
* @prop_name: Name of property to be parsed. Expected to hold phandle values
* @index: For properties holding a list of phandles, this is the index
* into the list.
* @list_name: Property name that is known to contain list of phandle(s) to
* supplier(s)
* @cells_name: property name that specifies phandles' arguments count
*
* This is a helper function to parse properties that have a known fixed name
* and are a list of phandles and phandle arguments.
*
* Returns:
* - phandle node pointer with refcount incremented. Caller must of_node_put()
* on it when done.
* - NULL if no phandle found at index
*/
static struct device_node *parse_prop_cells(struct device_node *np,
const char *prop_name, int index,
const char *list_name,
const char *cells_name)
{
struct of_phandle_args sup_args;
if (strcmp(prop_name, list_name))
return NULL;
if (of_parse_phandle_with_args(np, list_name, cells_name, index,
&sup_args))
return NULL;
return sup_args.np;
}
#define DEFINE_SIMPLE_PROP(fname, name, cells) \
static struct device_node *parse_##fname(struct device_node *np, \
const char *prop_name, int index) \
{ \
return parse_prop_cells(np, prop_name, index, name, cells); \
}
static int strcmp_suffix(const char *str, const char *suffix)
{
unsigned int len, suffix_len;
len = strlen(str);
suffix_len = strlen(suffix);
if (len <= suffix_len)
return -1;
return strcmp(str + len - suffix_len, suffix);
}
/**
* parse_suffix_prop_cells - Suffix property parsing function for suppliers
*
* @np: Pointer to device tree node containing a list
* @prop_name: Name of property to be parsed. Expected to hold phandle values
* @index: For properties holding a list of phandles, this is the index
* into the list.
* @suffix: Property suffix that is known to contain list of phandle(s) to
* supplier(s)
* @cells_name: property name that specifies phandles' arguments count
*
* This is a helper function to parse properties that have a known fixed suffix
* and are a list of phandles and phandle arguments.
*
* Returns:
* - phandle node pointer with refcount incremented. Caller must of_node_put()
* on it when done.
* - NULL if no phandle found at index
*/
static struct device_node *parse_suffix_prop_cells(struct device_node *np,
const char *prop_name, int index,
const char *suffix,
const char *cells_name)
{
struct of_phandle_args sup_args;
if (strcmp_suffix(prop_name, suffix))
return NULL;
if (of_parse_phandle_with_args(np, prop_name, cells_name, index,
&sup_args))
return NULL;
return sup_args.np;
}
#define DEFINE_SUFFIX_PROP(fname, suffix, cells) \
static struct device_node *parse_##fname(struct device_node *np, \
const char *prop_name, int index) \
{ \
return parse_suffix_prop_cells(np, prop_name, index, suffix, cells); \
}
/**
* struct supplier_bindings - Property parsing functions for suppliers
*
* @parse_prop: function name
* parse_prop() finds the node corresponding to a supplier phandle
* @parse_prop.np: Pointer to device node holding supplier phandle property
* @parse_prop.prop_name: Name of property holding a phandle value
* @parse_prop.index: For properties holding a list of phandles, this is the
* index into the list
*
* Returns:
* parse_prop() return values are
* - phandle node pointer with refcount incremented. Caller must of_node_put()
* on it when done.
* - NULL if no phandle found at index
*/
struct supplier_bindings {
struct device_node *(*parse_prop)(struct device_node *np,
const char *prop_name, int index);
};
DEFINE_SIMPLE_PROP(clocks, "clocks", "#clock-cells")
DEFINE_SIMPLE_PROP(interconnects, "interconnects", "#interconnect-cells")
DEFINE_SIMPLE_PROP(iommus, "iommus", "#iommu-cells")
DEFINE_SIMPLE_PROP(mboxes, "mboxes", "#mbox-cells")
DEFINE_SIMPLE_PROP(io_channels, "io-channel", "#io-channel-cells")
DEFINE_SIMPLE_PROP(interrupt_parent, "interrupt-parent", NULL)
DEFINE_SIMPLE_PROP(dmas, "dmas", "#dma-cells")
DEFINE_SUFFIX_PROP(regulators, "-supply", NULL)
DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
DEFINE_SUFFIX_PROP(gpios, "-gpios", "#gpio-cells")
static struct device_node *parse_iommu_maps(struct device_node *np,
const char *prop_name, int index)
{
if (strcmp(prop_name, "iommu-map"))
return NULL;
return of_parse_phandle(np, prop_name, (index * 4) + 1);
}
static const struct supplier_bindings of_supplier_bindings[] = {
{ .parse_prop = parse_clocks, },
{ .parse_prop = parse_interconnects, },
{ .parse_prop = parse_iommus, },
{ .parse_prop = parse_iommu_maps, },
{ .parse_prop = parse_mboxes, },
{ .parse_prop = parse_io_channels, },
{ .parse_prop = parse_interrupt_parent, },
{ .parse_prop = parse_dmas, },
{ .parse_prop = parse_regulators, },
{ .parse_prop = parse_gpio, },
{ .parse_prop = parse_gpios, },
{}
};
/**
* of_link_property - Create device links to suppliers listed in a property
* @dev: Consumer device
* @con_np: The consumer device tree node which contains the property
* @prop_name: Name of property to be parsed
*
* This function checks if the property @prop_name that is present in the
* @con_np device tree node is one of the known common device tree bindings
* that list phandles to suppliers. If @prop_name isn't one, this function
* doesn't do anything.
*
* If @prop_name is one, this function attempts to create device links from the
* consumer device @dev to all the devices of the suppliers listed in
* @prop_name.
*
* Any failed attempt to create a device link will NOT result in an immediate
* return. of_link_property() must create links to all the available supplier
* devices even when attempts to create a link to one or more suppliers fail.
*/
static int of_link_property(struct device *dev, struct device_node *con_np,
const char *prop_name)
{
struct device_node *phandle;
const struct supplier_bindings *s = of_supplier_bindings;
unsigned int i = 0;
bool matched = false;
int ret = 0;
u32 dl_flags;
if (dev->of_node == con_np)
dl_flags = DL_FLAG_AUTOPROBE_CONSUMER;
else
dl_flags = DL_FLAG_SYNC_STATE_ONLY;
/* Do not stop at first failed link, link all available suppliers. */
while (!matched && s->parse_prop) {
while ((phandle = s->parse_prop(con_np, prop_name, i))) {
matched = true;
i++;
if (of_link_to_phandle(dev, phandle, dl_flags)
== -EAGAIN)
ret = -EAGAIN;
of_node_put(phandle);
}
s++;
}
return ret;
}
static int of_link_to_suppliers(struct device *dev,
struct device_node *con_np)
{
struct device_node *child;
struct property *p;
int ret = 0;
for_each_property_of_node(con_np, p)
if (of_link_property(dev, con_np, p->name))
ret = -ENODEV;
for_each_child_of_node(con_np, child)
if (of_link_to_suppliers(dev, child) && !ret)
ret = -EAGAIN;
return ret;
}
static bool of_devlink;
core_param(of_devlink, of_devlink, bool, 0);
static int of_fwnode_add_links(const struct fwnode_handle *fwnode,
struct device *dev)
{
if (!of_devlink)
return 0;
if (unlikely(!is_of_node(fwnode)))
return 0;
return of_link_to_suppliers(dev, to_of_node(fwnode));
}
const struct fwnode_operations of_fwnode_ops = {
.get = of_fwnode_get,
.put = of_fwnode_put,
.device_is_available = of_fwnode_device_is_available,
.device_get_match_data = of_fwnode_device_get_match_data,
.property_present = of_fwnode_property_present,
.property_read_int_array = of_fwnode_property_read_int_array,
.property_read_string_array = of_fwnode_property_read_string_array,
.get_name = of_fwnode_get_name,
.get_name_prefix = of_fwnode_get_name_prefix,
.get_parent = of_fwnode_get_parent,
.get_next_child_node = of_fwnode_get_next_child_node,
.get_named_child_node = of_fwnode_get_named_child_node,
.get_reference_args = of_fwnode_get_reference_args,
.graph_get_next_endpoint = of_fwnode_graph_get_next_endpoint,
.graph_get_remote_endpoint = of_fwnode_graph_get_remote_endpoint,
.graph_get_port_parent = of_fwnode_graph_get_port_parent,
.graph_parse_endpoint = of_fwnode_graph_parse_endpoint,
.add_links = of_fwnode_add_links,
};
EXPORT_SYMBOL_GPL(of_fwnode_ops);