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-rw-r--r--drivers/of/property.c806
1 files changed, 806 insertions, 0 deletions
diff --git a/drivers/of/property.c b/drivers/of/property.c
new file mode 100644
index 000000000000..07c7c36c5ca8
--- /dev/null
+++ b/drivers/of/property.c
@@ -0,0 +1,806 @@
+/*
+ * 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.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#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 "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 %s is not a multiple of %d\n",
+ propname, np->full_name, 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 return value, modified only if return value is 0.
+ * @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 return value, modified only if return value is 0.
+ * @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 value, modified only if return value is 0.
+ * @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 return value, modified only if return value is 0.
+ * @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 %s has no parent node\n",
+ __func__, node->full_name);
+
+ 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_cmp(port->name, "port") != 0)
+ 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 %s\n",
+ parent->full_name);
+ return NULL;
+ }
+ } else {
+ port = of_get_parent(prev);
+ if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n",
+ __func__, prev->full_name))
+ 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_cmp(port->name, "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.
+ */
+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;
+
+ /* 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_cmp(node->name, "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;
+
+ /* Get remote endpoint node. */
+ np = of_graph_get_remote_endpoint(node);
+
+ return of_graph_get_port_parent(np);
+}
+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 %s\n",
+ port, endpoint, node->full_name);
+ 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");
+ return NULL;
+ }
+
+ return remote;
+}
+EXPORT_SYMBOL(of_graph_get_remote_node);
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-26 01:56:58 +0300