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+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (c) 2017 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#ifndef _DM_OFNODE_H
+#define _DM_OFNODE_H
+
+/* TODO(sjg@chromium.org): Drop fdtdec.h include */
+#include <fdtdec.h>
+#include <dm/of.h>
+
+/* Enable checks to protect against invalid calls */
+#undef OF_CHECKS
+
+struct resource;
+
+/**
+ * ofnode - reference to a device tree node
+ *
+ * This union can hold either a straightforward pointer to a struct device_node
+ * in the live device tree, or an offset within the flat device tree. In the
+ * latter case, the pointer value is just the integer offset within the flat DT.
+ *
+ * Thus we can reference nodes in both the live tree (once available) and the
+ * flat tree (until then). Functions are available to translate between an
+ * ofnode and either an offset or a struct device_node *.
+ *
+ * The reference can also hold a null offset, in which case the pointer value
+ * here is NULL. This corresponds to a struct device_node * value of
+ * NULL, or an offset of -1.
+ *
+ * There is no ambiguity as to whether ofnode holds an offset or a node
+ * pointer: when the live tree is active it holds a node pointer, otherwise it
+ * holds an offset. The value itself does not need to be unique and in theory
+ * the same value could point to a valid device node or a valid offset. We
+ * could arrange for a unique value to be used (e.g. by making the pointer
+ * point to an offset within the flat device tree in the case of an offset) but
+ * this increases code size slightly due to the subtraction. Since it offers no
+ * real benefit, the approach described here seems best.
+ *
+ * For now these points use constant types, since we don't allow writing
+ * the DT.
+ *
+ * @np: Pointer to device node, used for live tree
+ * @of_offset: Pointer into flat device tree, used for flat tree. Note that this
+ * is not a really a pointer to a node: it is an offset value. See above.
+ */
+typedef union ofnode_union {
+ const struct device_node *np; /* will be used for future live tree */
+ long of_offset;
+} ofnode;
+
+struct ofnode_phandle_args {
+ ofnode node;
+ int args_count;
+ uint32_t args[OF_MAX_PHANDLE_ARGS];
+};
+
+/**
+ * _ofnode_to_np() - convert an ofnode to a live DT node pointer
+ *
+ * This cannot be called if the reference contains an offset.
+ *
+ * @node: Reference containing struct device_node * (possibly invalid)
+ * @return pointer to device node (can be NULL)
+ */
+static inline const struct device_node *ofnode_to_np(ofnode node)
+{
+#ifdef OF_CHECKS
+ if (!of_live_active())
+ return NULL;
+#endif
+ return node.np;
+}
+
+/**
+ * ofnode_to_offset() - convert an ofnode to a flat DT offset
+ *
+ * This cannot be called if the reference contains a node pointer.
+ *
+ * @node: Reference containing offset (possibly invalid)
+ * @return DT offset (can be -1)
+ */
+static inline int ofnode_to_offset(ofnode node)
+{
+#ifdef OF_CHECKS
+ if (of_live_active())
+ return -1;
+#endif
+ return node.of_offset;
+}
+
+/**
+ * ofnode_valid() - check if an ofnode is valid
+ *
+ * @return true if the reference contains a valid ofnode, false if it is NULL
+ */
+static inline bool ofnode_valid(ofnode node)
+{
+ if (of_live_active())
+ return node.np != NULL;
+ else
+ return node.of_offset != -1;
+}
+
+/**
+ * offset_to_ofnode() - convert a DT offset to an ofnode
+ *
+ * @of_offset: DT offset (either valid, or -1)
+ * @return reference to the associated DT offset
+ */
+static inline ofnode offset_to_ofnode(int of_offset)
+{
+ ofnode node;
+
+ if (of_live_active())
+ node.np = NULL;
+ else
+ node.of_offset = of_offset;
+
+ return node;
+}
+
+/**
+ * np_to_ofnode() - convert a node pointer to an ofnode
+ *
+ * @np: Live node pointer (can be NULL)
+ * @return reference to the associated node pointer
+ */
+static inline ofnode np_to_ofnode(const struct device_node *np)
+{
+ ofnode node;
+
+ node.np = np;
+
+ return node;
+}
+
+/**
+ * ofnode_is_np() - check if a reference is a node pointer
+ *
+ * This function associated that if there is a valid live tree then all
+ * references will use it. This is because using the flat DT when the live tree
+ * is valid is not permitted.
+ *
+ * @node: reference to check (possibly invalid)
+ * @return true if the reference is a live node pointer, false if it is a DT
+ * offset
+ */
+static inline bool ofnode_is_np(ofnode node)
+{
+#ifdef OF_CHECKS
+ /*
+ * Check our assumption that flat tree offsets are not used when a
+ * live tree is in use.
+ */
+ assert(!ofnode_valid(node) ||
+ (of_live_active() ? _ofnode_to_np(node)
+ : _ofnode_to_np(node)));
+#endif
+ return of_live_active() && ofnode_valid(node);
+}
+
+/**
+ * ofnode_equal() - check if two references are equal
+ *
+ * @return true if equal, else false
+ */
+static inline bool ofnode_equal(ofnode ref1, ofnode ref2)
+{
+ /* We only need to compare the contents */
+ return ref1.of_offset == ref2.of_offset;
+}
+
+/**
+ * ofnode_null() - Obtain a null ofnode
+ *
+ * This returns an ofnode which points to no node. It works both with the flat
+ * tree and livetree.
+ */
+static inline ofnode ofnode_null(void)
+{
+ ofnode node;
+
+ if (of_live_active())
+ node.np = NULL;
+ else
+ node.of_offset = -1;
+
+ return node;
+}
+
+/**
+ * ofnode_read_u32() - Read a 32-bit integer from a property
+ *
+ * @ref: valid node reference to read property from
+ * @propname: name of the property to read from
+ * @outp: place to put value (if found)
+ * @return 0 if OK, -ve on error
+ */
+int ofnode_read_u32(ofnode node, const char *propname, u32 *outp);
+
+/**
+ * ofnode_read_s32() - Read a 32-bit integer from a property
+ *
+ * @ref: valid node reference to read property from
+ * @propname: name of the property to read from
+ * @outp: place to put value (if found)
+ * @return 0 if OK, -ve on error
+ */
+static inline int ofnode_read_s32(ofnode node, const char *propname,
+ s32 *out_value)
+{
+ return ofnode_read_u32(node, propname, (u32 *)out_value);
+}
+
+/**
+ * ofnode_read_u32_default() - Read a 32-bit integer from a property
+ *
+ * @ref: valid node reference to read property from
+ * @propname: name of the property to read from
+ * @def: default value to return if the property has no value
+ * @return property value, or @def if not found
+ */
+u32 ofnode_read_u32_default(ofnode ref, const char *propname, u32 def);
+
+/**
+ * ofnode_read_s32_default() - Read a 32-bit integer from a property
+ *
+ * @ref: valid node reference to read property from
+ * @propname: name of the property to read from
+ * @def: default value to return if the property has no value
+ * @return property value, or @def if not found
+ */
+int ofnode_read_s32_default(ofnode node, const char *propname, s32 def);
+
+/**
+ * ofnode_read_u64() - Read a 64-bit integer from a property
+ *
+ * @node: valid node reference to read property from
+ * @propname: name of the property to read from
+ * @outp: place to put value (if found)
+ * @return 0 if OK, -ve on error
+ */
+int ofnode_read_u64(ofnode node, const char *propname, u64 *outp);
+
+/**
+ * ofnode_read_u64_default() - Read a 64-bit integer from a property
+ *
+ * @ref: valid node reference to read property from
+ * @propname: name of the property to read from
+ * @def: default value to return if the property has no value
+ * @return property value, or @def if not found
+ */
+u64 ofnode_read_u64_default(ofnode node, const char *propname, u64 def);
+
+/**
+ * ofnode_read_string() - Read a string from a property
+ *
+ * @ref: valid node reference to read property from
+ * @propname: name of the property to read
+ * @return string from property value, or NULL if there is no such property
+ */
+const char *ofnode_read_string(ofnode node, const char *propname);
+
+/**
+ * ofnode_read_u32_array() - Find and read an array of 32 bit integers
+ *
+ * @node: valid node reference to read property from
+ * @propname: name of the property to read
+ * @out_values: pointer to return value, modified only if return value is 0
+ * @sz: number of array elements to read
+ * @return 0 if OK, -ve on error
+ *
+ * Search for a property in a device node and read 32-bit value(s) 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_values is modified only if a valid u32 value can be decoded.
+ */
+int ofnode_read_u32_array(ofnode node, const char *propname,
+ u32 *out_values, size_t sz);
+
+/**
+ * ofnode_read_bool() - read a boolean value from a property
+ *
+ * @node: valid node reference to read property from
+ * @propname: name of property to read
+ * @return true if property is present (meaning true), false if not present
+ */
+bool ofnode_read_bool(ofnode node, const char *propname);
+
+/**
+ * ofnode_find_subnode() - find a named subnode of a parent node
+ *
+ * @node: valid reference to parent node
+ * @subnode_name: name of subnode to find
+ * @return reference to subnode (which can be invalid if there is no such
+ * subnode)
+ */
+ofnode ofnode_find_subnode(ofnode node, const char *subnode_name);
+
+/**
+ * ofnode_first_subnode() - find the first subnode of a parent node
+ *
+ * @node: valid reference to a valid parent node
+ * @return reference to the first subnode (which can be invalid if the parent
+ * node has no subnodes)
+ */
+ofnode ofnode_first_subnode(ofnode node);
+
+/**
+ * ofnode_next_subnode() - find the next sibling of a subnode
+ *
+ * @node: valid reference to previous node (sibling)
+ * @return reference to the next subnode (which can be invalid if the node
+ * has no more siblings)
+ */
+ofnode ofnode_next_subnode(ofnode node);
+
+/**
+ * ofnode_get_parent() - get the ofnode's parent (enclosing ofnode)
+ *
+ * @node: valid node to look up
+ * @return ofnode reference of the parent node
+ */
+ofnode ofnode_get_parent(ofnode node);
+
+/**
+ * ofnode_get_name() - get the name of a node
+ *
+ * @node: valid node to look up
+ * @return name of node
+ */
+const char *ofnode_get_name(ofnode node);
+
+/**
+ * ofnode_get_by_phandle() - get ofnode from phandle
+ *
+ * @phandle: phandle to look up
+ * @return ofnode reference to the phandle
+ */
+ofnode ofnode_get_by_phandle(uint phandle);
+
+/**
+ * ofnode_read_size() - read the size of a property
+ *
+ * @node: node to check
+ * @propname: property to check
+ * @return size of property if present, or -EINVAL if not
+ */
+int ofnode_read_size(ofnode node, const char *propname);
+
+/**
+ * ofnode_get_addr_size_index() - get an address/size from a node
+ * based on index
+ *
+ * This reads the register address/size from a node based on index
+ *
+ * @node: node to read from
+ * @index: Index of address to read (0 for first)
+ * @size: Pointer to size of the address
+ * @return address, or FDT_ADDR_T_NONE if not present or invalid
+ */
+phys_addr_t ofnode_get_addr_size_index(ofnode node, int index,
+ fdt_size_t *size);
+
+/**
+ * ofnode_get_addr_index() - get an address from a node
+ *
+ * This reads the register address from a node
+ *
+ * @node: node to read from
+ * @index: Index of address to read (0 for first)
+ * @return address, or FDT_ADDR_T_NONE if not present or invalid
+ */
+phys_addr_t ofnode_get_addr_index(ofnode node, int index);
+
+/**
+ * ofnode_get_addr() - get an address from a node
+ *
+ * This reads the register address from a node
+ *
+ * @node: node to read from
+ * @return address, or FDT_ADDR_T_NONE if not present or invalid
+ */
+phys_addr_t ofnode_get_addr(ofnode node);
+
+/**
+ * ofnode_stringlist_search() - find a string in a string list and return index
+ *
+ * Note that it is possible for this function to succeed on property values
+ * that are not NUL-terminated. That's because the function will stop after
+ * finding the first occurrence of @string. This can for example happen with
+ * small-valued cell properties, such as #address-cells, when searching for
+ * the empty string.
+ *
+ * @node: node to check
+ * @propname: name of the property containing the string list
+ * @string: string to look up in the string list
+ *
+ * @return:
+ * the index of the string in the list of strings
+ * -ENODATA if the property is not found
+ * -EINVAL on some other error
+ */
+int ofnode_stringlist_search(ofnode node, const char *propname,
+ const char *string);
+
+/**
+ * ofnode_read_string_index() - obtain an indexed string from a string list
+ *
+ * Note that this will successfully extract strings from properties with
+ * non-NUL-terminated values. For example on small-valued cell properties
+ * this function will return the empty string.
+ *
+ * If non-NULL, the length of the string (on success) or a negative error-code
+ * (on failure) will be stored in the integer pointer to by lenp.
+ *
+ * @node: node to check
+ * @propname: name of the property containing the string list
+ * @index: index of the string to return
+ * @lenp: return location for the string length or an error code on failure
+ *
+ * @return:
+ * length of string, if found or -ve error value if not found
+ */
+int ofnode_read_string_index(ofnode node, const char *propname, int index,
+ const char **outp);
+
+/**
+ * ofnode_read_string_count() - find the number of strings in a string list
+ *
+ * @node: node to check
+ * @propname: name of the property containing the string list
+ * @return:
+ * number of strings in the list, or -ve error value if not found
+ */
+int ofnode_read_string_count(ofnode node, const char *property);
+
+/**
+ * ofnode_parse_phandle_with_args() - Find a node pointed by phandle in a list
+ *
+ * This function is useful to parse lists of phandles and their arguments.
+ * Returns 0 on success and fills out_args, on error returns appropriate
+ * errno value.
+ *
+ * Caller is responsible to call of_node_put() on the returned out_args->np
+ * pointer.
+ *
+ * Example:
+ *
+ * phandle1: node1 {
+ * #list-cells = <2>;
+ * }
+ *
+ * phandle2: node2 {
+ * #list-cells = <1>;
+ * }
+ *
+ * node3 {
+ * list = <&phandle1 1 2 &phandle2 3>;
+ * }
+ *
+ * To get a device_node of the `node2' node you may call this:
+ * ofnode_parse_phandle_with_args(node3, "list", "#list-cells", 0, 1, &args);
+ *
+ * @node: device tree node containing a list
+ * @list_name: property name that contains a list
+ * @cells_name: property name that specifies phandles' arguments count
+ * @cells_count: Cell count to use if @cells_name is NULL
+ * @index: index of a phandle to parse out
+ * @out_args: optional pointer to output arguments structure (will be filled)
+ * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
+ * @list_name does not exist, -EINVAL if a phandle was not found,
+ * @cells_name could not be found, the arguments were truncated or there
+ * were too many arguments.
+ */
+int ofnode_parse_phandle_with_args(ofnode node, const char *list_name,
+ const char *cells_name, int cell_count,
+ int index,
+ struct ofnode_phandle_args *out_args);
+
+/**
+ * ofnode_count_phandle_with_args() - Count number of phandle in a list
+ *
+ * This function is useful to count phandles into a list.
+ * Returns number of phandle on success, on error returns appropriate
+ * errno value.
+ *
+ * @node: device tree node containing a list
+ * @list_name: property name that contains a list
+ * @cells_name: property name that specifies phandles' arguments count
+ * @return number of phandle on success, -ENOENT if @list_name does not
+ * exist, -EINVAL if a phandle was not found, @cells_name could not
+ * be found.
+ */
+int ofnode_count_phandle_with_args(ofnode node, const char *list_name,
+ const char *cells_name);
+
+/**
+ * ofnode_path() - find a node by full path
+ *
+ * @path: Full path to node, e.g. "/bus/spi@1"
+ * @return reference to the node found. Use ofnode_valid() to check if it exists
+ */
+ofnode ofnode_path(const char *path);
+
+/**
+ * ofnode_get_chosen_prop() - get the value of a chosen property
+ *
+ * This looks for a property within the /chosen node and returns its value
+ *
+ * @propname: Property name to look for
+ * @return property value if found, else NULL
+ */
+const char *ofnode_get_chosen_prop(const char *propname);
+
+/**
+ * ofnode_get_chosen_node() - get the chosen node
+ *
+ * @return the chosen node if present, else ofnode_null()
+ */
+ofnode ofnode_get_chosen_node(const char *name);
+
+struct display_timing;
+/**
+ * ofnode_decode_display_timing() - decode display timings
+ *
+ * Decode display timings from the supplied 'display-timings' node.
+ * See doc/device-tree-bindings/video/display-timing.txt for binding
+ * information.
+ *
+ * @node 'display-timing' node containing the timing subnodes
+ * @index Index number to read (0=first timing subnode)
+ * @config Place to put timings
+ * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
+ */
+int ofnode_decode_display_timing(ofnode node, int index,
+ struct display_timing *config);
+
+/**
+ * ofnode_get_property()- - get a pointer to the value of a node property
+ *
+ * @node: node to read
+ * @propname: property to read
+ * @lenp: place to put length on success
+ * @return pointer to property, or NULL if not found
+ */
+const void *ofnode_get_property(ofnode node, const char *propname, int *lenp);
+
+/**
+ * ofnode_is_available() - check if a node is marked available
+ *
+ * @node: node to check
+ * @return true if node's 'status' property is "okay" (or is missing)
+ */
+bool ofnode_is_available(ofnode node);
+
+/**
+ * ofnode_get_addr_size() - get address and size from a property
+ *
+ * This does no address translation. It simply reads an property that contains
+ * an address and a size value, one after the other.
+ *
+ * @node: node to read from
+ * @propname: property to read
+ * @sizep: place to put size value (on success)
+ * @return address value, or FDT_ADDR_T_NONE on error
+ */
+phys_addr_t ofnode_get_addr_size(ofnode node, const char *propname,
+ phys_size_t *sizep);
+
+/**
+ * ofnode_read_u8_array_ptr() - find an 8-bit array
+ *
+ * Look up a property in a node and return a pointer to its contents as a
+ * byte array of given length. The property must have at least enough data
+ * for the array (count bytes). It may have more, but this will be ignored.
+ * The data is not copied.
+ *
+ * @node node to examine
+ * @propname name of property to find
+ * @sz number of array elements
+ * @return pointer to byte array if found, or NULL if the property is not
+ * found or there is not enough data
+ */
+const uint8_t *ofnode_read_u8_array_ptr(ofnode node, const char *propname,
+ size_t sz);
+
+/**
+ * ofnode_read_pci_addr() - look up a PCI address
+ *
+ * Look at an address property in a node and return the PCI address which
+ * corresponds to the given type in the form of fdt_pci_addr.
+ * The property must hold one fdt_pci_addr with a lengh.
+ *
+ * @node node to examine
+ * @type pci address type (FDT_PCI_SPACE_xxx)
+ * @propname name of property to find
+ * @addr returns pci address in the form of fdt_pci_addr
+ * @return 0 if ok, -ENOENT if the property did not exist, -EINVAL if the
+ * format of the property was invalid, -ENXIO if the requested
+ * address type was not found
+ */
+int ofnode_read_pci_addr(ofnode node, enum fdt_pci_space type,
+ const char *propname, struct fdt_pci_addr *addr);
+
+/**
+ * ofnode_read_pci_vendev() - look up PCI vendor and device id
+ *
+ * Look at the compatible property of a device node that represents a PCI
+ * device and extract pci vendor id and device id from it.
+ *
+ * @param node node to examine
+ * @param vendor vendor id of the pci device
+ * @param device device id of the pci device
+ * @return 0 if ok, negative on error
+ */
+int ofnode_read_pci_vendev(ofnode node, u16 *vendor, u16 *device);
+
+/**
+ * ofnode_read_addr_cells() - Get the number of address cells for a node
+ *
+ * This walks back up the tree to find the closest #address-cells property
+ * which controls the given node.
+ *
+ * @node: Node to check
+ * @return number of address cells this node uses
+ */
+int ofnode_read_addr_cells(ofnode node);
+
+/**
+ * ofnode_read_size_cells() - Get the number of size cells for a node
+ *
+ * This walks back up the tree to find the closest #size-cells property
+ * which controls the given node.
+ *
+ * @node: Node to check
+ * @return number of size cells this node uses
+ */
+int ofnode_read_size_cells(ofnode node);
+
+/**
+ * ofnode_read_simple_addr_cells() - Get the address cells property in a node
+ *
+ * This function matches fdt_address_cells().
+ *
+ * @np: Node pointer to check
+ * @return value of #address-cells property in this node, or 2 if none
+ */
+int ofnode_read_simple_addr_cells(ofnode node);
+
+/**
+ * ofnode_read_simple_size_cells() - Get the size cells property in a node
+ *
+ * This function matches fdt_size_cells().
+ *
+ * @np: Node pointer to check
+ * @return value of #size-cells property in this node, or 2 if none
+ */
+int ofnode_read_simple_size_cells(ofnode node);
+
+/**
+ * ofnode_pre_reloc() - check if a node should be bound before relocation
+ *
+ * Device tree nodes can be marked as needing-to-be-bound in the loader stages
+ * via special device tree properties.
+ *
+ * Before relocation this function can be used to check if nodes are required
+ * in either SPL or TPL stages.
+ *
+ * After relocation and jumping into the real U-Boot binary it is possible to
+ * determine if a node was bound in one of SPL/TPL stages.
+ *
+ * There are 4 settings currently in use
+ * - u-boot,dm-pre-proper: U-Boot proper pre-relocation only
+ * - u-boot,dm-pre-reloc: legacy and indicates any of TPL or SPL
+ * Existing platforms only use it to indicate nodes needed in
+ * SPL. Should probably be replaced by u-boot,dm-spl for
+ * new platforms.
+ * - u-boot,dm-spl: SPL and U-Boot pre-relocation
+ * - u-boot,dm-tpl: TPL and U-Boot pre-relocation
+ *
+ * @node: node to check
+ * @return true if node is needed in SPL/TL, false otherwise
+ */
+bool ofnode_pre_reloc(ofnode node);
+
+/**
+ * ofnode_read_resource() - Read a resource from a node
+ *
+ * Read resource information from a node at the given index
+ *
+ * @node: Node to read from
+ * @index: Index of resource to read (0 = first)
+ * @res: Returns resource that was read, on success
+ * @return 0 if OK, -ve on error
+ */
+int ofnode_read_resource(ofnode node, uint index, struct resource *res);
+
+/**
+ * ofnode_read_resource_byname() - Read a resource from a node by name
+ *
+ * Read resource information from a node matching the given name. This uses a
+ * 'reg-names' string list property with the names matching the associated
+ * 'reg' property list.
+ *
+ * @node: Node to read from
+ * @name: Name of resource to read
+ * @res: Returns resource that was read, on success
+ * @return 0 if OK, -ve on error
+ */
+int ofnode_read_resource_byname(ofnode node, const char *name,
+ struct resource *res);
+
+/**
+ * ofnode_by_compatible() - Find the next compatible node
+ *
+ * Find the next node after @from that is compatible with @compat
+ *
+ * @from: ofnode to start from (use ofnode_null() to start at the beginning)
+ * @compat: Compatible string to match
+ * @return ofnode found, or ofnode_null() if none
+ */
+ofnode ofnode_by_compatible(ofnode from, const char *compat);
+
+/**
+ * ofnode_by_prop_value() - Find the next node with given property value
+ *
+ * Find the next node after @from that has a @propname with a value
+ * @propval and a length @proplen.
+ *
+ * @from: ofnode to start from (use ofnode_null() to start at the
+ * beginning) @propname: property name to check @propval: property value to
+ * search for @proplen: length of the value in propval @return ofnode
+ * found, or ofnode_null() if none
+ */
+ofnode ofnode_by_prop_value(ofnode from, const char *propname,
+ const void *propval, int proplen);
+
+/**
+ * ofnode_for_each_subnode() - iterate over all subnodes of a parent
+ *
+ * @node: child node (ofnode, lvalue)
+ * @parent: parent node (ofnode)
+ *
+ * This is a wrapper around a for loop and is used like so:
+ *
+ * ofnode node;
+ *
+ * ofnode_for_each_subnode(node, parent) {
+ * Use node
+ * ...
+ * }
+ *
+ * Note that this is implemented as a macro and @node is used as
+ * iterator in the loop. The parent variable can be a constant or even a
+ * literal.
+ */
+#define ofnode_for_each_subnode(node, parent) \
+ for (node = ofnode_first_subnode(parent); \
+ ofnode_valid(node); \
+ node = ofnode_next_subnode(node))
+
+/**
+ * ofnode_translate_address() - Translate a device-tree address
+ *
+ * Translate an address from the device-tree into a CPU physical address. This
+ * function walks up the tree and applies the various bus mappings along the
+ * way.
+ *
+ * @ofnode: Device tree node giving the context in which to translate the
+ * address
+ * @in_addr: pointer to the address to translate
+ * @return the translated address; OF_BAD_ADDR on error
+ */
+u64 ofnode_translate_address(ofnode node, const fdt32_t *in_addr);
+
+/**
+ * ofnode_translate_dma_address() - Translate a device-tree DMA address
+ *
+ * Translate a DMA address from the device-tree into a CPU physical address.
+ * This function walks up the tree and applies the various bus mappings along
+ * the way.
+ *
+ * @ofnode: Device tree node giving the context in which to translate the
+ * DMA address
+ * @in_addr: pointer to the DMA address to translate
+ * @return the translated DMA address; OF_BAD_ADDR on error
+ */
+u64 ofnode_translate_dma_address(ofnode node, const fdt32_t *in_addr);
+
+/**
+ * ofnode_device_is_compatible() - check if the node is compatible with compat
+ *
+ * This allows to check whether the node is comaptible with the compat.
+ *
+ * @node: Device tree node for which compatible needs to be verified.
+ * @compat: Compatible string which needs to verified in the given node.
+ * @return true if OK, false if the compatible is not found
+ */
+int ofnode_device_is_compatible(ofnode node, const char *compat);
+
+/**
+ * ofnode_write_prop() - Set a property of a ofnode
+ *
+ * Note that the value passed to the function is *not* allocated by the
+ * function itself, but must be allocated by the caller if necessary.
+ *
+ * @node: The node for whose property should be set
+ * @propname: The name of the property to set
+ * @len: The length of the new value of the property
+ * @value: The new value of the property (must be valid prior to calling
+ * the function)
+ * @return 0 if successful, -ve on error
+ */
+int ofnode_write_prop(ofnode node, const char *propname, int len,
+ const void *value);
+
+/**
+ * ofnode_write_string() - Set a string property of a ofnode
+ *
+ * Note that the value passed to the function is *not* allocated by the
+ * function itself, but must be allocated by the caller if necessary.
+ *
+ * @node: The node for whose string property should be set
+ * @propname: The name of the string property to set
+ * @value: The new value of the string property (must be valid prior to
+ * calling the function)
+ * @return 0 if successful, -ve on error
+ */
+int ofnode_write_string(ofnode node, const char *propname, const char *value);
+
+/**
+ * ofnode_set_enabled() - Enable or disable a device tree node given by its
+ * ofnode
+ *
+ * This function effectively sets the node's "status" property to either "okay"
+ * or "disable", hence making it available for driver model initialization or
+ * not.
+ *
+ * @node: The node to enable
+ * @value: Flag that tells the function to either disable or enable the
+ * node
+ * @return 0 if successful, -ve on error
+ */
+int ofnode_set_enabled(ofnode node, bool value);
+
+#endif