Merge branch 'dt/property-move' into dt/next

3 files changed, 809 insertions, 734 deletions

diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index d7efd9d458aa..97dc01c81438 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -1,4 +1,4 @@
-obj-y = base.o device.o platform.o
+obj-y = base.o device.o platform.o property.o
 obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
 obj-$(CONFIG_OF_FLATTREE) += fdt.o
 obj-$(CONFIG_OF_EARLY_FLATTREE) += fdt_address.o
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 87b4968f3d8f..686628d1dfa6 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1119,458 +1119,6 @@ struct device_node *of_find_node_by_phandle(phandle handle)
 }
 EXPORT_SYMBOL(of_find_node_by_phandle);
 
-/**
- * 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);
-
 void of_print_phandle_args(const char *msg, const struct of_phandle_args *args)
 {
         int i;
@@ -1607,6 +1155,7 @@ int of_phandle_iterator_init(struct of_phandle_iterator *it,
 
         return 0;
 }
+EXPORT_SYMBOL_GPL(of_phandle_iterator_init);
 
 int of_phandle_iterator_next(struct of_phandle_iterator *it)
 {
@@ -1676,6 +1225,7 @@ err:
 
         return -EINVAL;
 }
+EXPORT_SYMBOL_GPL(of_phandle_iterator_next);
 
 int of_phandle_iterator_args(struct of_phandle_iterator *it,
                              uint32_t *args,
@@ -2217,47 +1767,6 @@ int of_alias_get_highest_id(const char *stem)
 }
 EXPORT_SYMBOL_GPL(of_alias_get_highest_id);
 
-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_console_check() - Test and setup console for DT setup
  * @dn - Pointer to device node
@@ -2331,243 +1840,3 @@ int of_find_last_cache_level(unsigned int cpu)
 
         return cache_level;
 }
-
-/**
- * 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_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;
-        unsigned int depth;
-
-        /* Get remote endpoint node. */
-        np = of_parse_phandle(node, "remote-endpoint", 0);
-
-        /* Walk 3 levels up only if there is 'ports' node. */
-        for (depth = 3; depth && np; depth--) {
-                np = of_get_next_parent(np);
-                if (depth == 2 && of_node_cmp(np->name, "ports"))
-                        break;
-        }
-        return 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_parse_phandle(node, "remote-endpoint", 0);
-        if (!np)
-                return NULL;
-        return of_get_next_parent(np);
-}
-EXPORT_SYMBOL(of_graph_get_remote_port);
-
-/**
- * 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);
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);