Parameters

structdevice_node*prev

Previous node or NULL to start iterationof_node_put() will be called on it

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

constchar*const*compats

NULL terminated array of compatible strings to look for in root node’s compatible property.

Description

Returns true if the root node has any of the given compatible values in itscompatible property.

Parameters

conststructof_device_id*matches

NULL terminated array of of_device_id match structures to search in

Description

Returns true if the root node has any of the given compatible values in itscompatible property.

Parameters

conststructof_device_id*matches

NULL terminated array of of_device_id match structures to search in

Description

Returns data associated with matched entry or NULL

Parameters

conststructdevice_node*device

Node to check for availability

Return

True if the status property is absent or set to “okay” or “ok”,false otherwise

Parameters

conststructdevice_node*device

Node to check for endianness

Return

True if the device has a “big-endian” property, or if the kernelwas compiled for BEand the device has a “native-endian” property.Returns false otherwise.

Description

Callers would nominally use ioread32be/iowrite32be ifof_device_is_big_endian() == true, or readl/writel otherwise.

Parameters

conststructdevice_node*node

Node to get parent

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

structdevice_node*node

Node to get parent of

Description

This is likeof_get_parent() except that it drops therefcount on the passed node, making it suitable for iteratingthrough a node’s parents.

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

conststructdevice_node*node

parent node

structdevice_node*prev

previous child of the parent node, or NULL to get first

Return

A node pointer with refcount incremented, useof_node_put() onit when done. Returns NULL when prev is the last child. Decrements therefcount of prev.

Parameters

conststructdevice_node*node

parent node

structdevice_node*prev

previous child of the parent node, or NULL to get first

constchar*prefix

prefix that the node name should have

Description

This function is likeof_get_next_child(), except that it automaticallyskips any nodes whose name doesn’t have the given prefix.

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

conststructdevice_node*node

parent node

structdevice_node*prev

previous child of the parent node, or NULL to get first

Description

This function is likeof_get_next_child(), except that itautomatically skips any disabled nodes (i.e. status = “disabled”).

Parameters

conststructdevice_node*node

parent node

structdevice_node*prev

previous child of the parent node, or NULL to get first

Description

This function is likeof_get_next_child(), except that itautomatically skips any disabled nodes (i.e. status = “disabled”).

Parameters

structdevice_node*prev

previous child of the /cpus node, or NULL to get first

Description

Unusable CPUs (those with the status property set to “fail” or “fail-...”)will be skipped.

Return

A cpu node pointer with refcount incremented, useof_node_put()on it when done. Returns NULL when prev is the last child. Decrementsthe refcount of prev.

Parameters

conststructdevice_node*parent

parent node

constchar*compatible

compatible string

Description

Lookup child node whose compatible property contains the given compatiblestring.

Return

a node pointer with refcount incremented, useof_node_put() on itwhen done; or NULL if not found.

Parameters

conststructdevice_node*node

parent node

constchar*name

child name to look for.

Description

This function looks for child node for given matching name

Return

A node pointer if found, with refcount incremented, useof_node_put() on it when done.Returns NULL if node is not found.

Parameters

conststructdevice_node*node

parent node

constchar*name

child name to look for.

Description

This function looks for child node for given matching name and checks thedevice’s availability for use.

Return

A node pointer if found, with refcount incremented, useof_node_put() on it when done.Returns NULL if node is not found.

Parameters

constchar*path

Either the full path to match, or if the path does notstart with ‘/’, the name of a property of the /aliasesnode (an alias). In the case of an alias, the nodematching the alias’ value will be returned.

constchar**opts

Address of a pointer into which to store the start ofan options string appended to the end of the path witha ‘:’ separator.

Description

Valid paths:

• /foo/bar Full path

• foo Valid alias

• foo/bar Valid alias + relative path

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

structdevice_node*from

The node to start searching from or NULL; the nodeyou pass will not be searched, only the next onewill. Typically, you pass what the previous callreturned.of_node_put() will be called onfrom.

constchar*name

The name string to match against

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

structdevice_node*from

The node to start searching from, or NULL to start searchingthe entire device tree. The node you pass will not besearched, only the next one will; typically, you passwhat the previous call returned.of_node_put() will becalled on from for you.

constchar*type

The type string to match against

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

structdevice_node*from

The node to start searching from or NULL, the nodeyou pass will not be searched, only the next onewill; typically, you pass what the previous callreturned.of_node_put() will be called on it

constchar*type

The type string to match “device_type” or NULL to ignore

constchar*compatible

The string to match to one of the tokens in the device“compatible” list.

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

structdevice_node*from

The node to start searching from or NULL, the nodeyou pass will not be searched, only the next onewill; typically, you pass what the previous callreturned.of_node_put() will be called on it

constchar*prop_name

The name of the property to look for.

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

conststructof_device_id*matches

array of of device match structures to search in

conststructdevice_node*node

the of device structure to match against

Description

Low level utility function used by device matching.

Parameters

structdevice_node*from

The node to start searching from or NULL, the nodeyou pass will not be searched, only the next onewill; typically, you pass what the previous callreturned.of_node_put() will be called on it

conststructof_device_id*matches

array of of device match structures to search in

conststructof_device_id**match

Updated to point at the matches entry which matched

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

conststructdevice_node*node

pointer to a device tree node

char*alias

Pointer to buffer that alias value will be copied into

intlen

Length of alias value

Description

Based on the value of the compatible property, this routine will attemptto choose an appropriate alias value for a particular device tree node.It does this by stripping the manufacturer prefix (as delimited by a ‘,’)from the first entry in the compatible list property.

Note

The matching on just the “product” side of the compatible is a relicfrom I2C and SPI. Please do not add any new user.

Return

This routine returns 0 on success, <0 on failure.

Parameters

phandlehandle

phandle of the node to find

Return

A node pointer with refcount incremented, useof_node_put() on it when done.

Parameters

conststructdevice_node*np

pointer to a device tree node containing a list

constchar*list_name

property name that contains a list

constchar*stem_name

stem of property names that specify phandles’ arguments count

intindex

index of a phandle to parse out

structof_phandle_args*out_args

optional pointer to output arguments structure (will be filled)

Description

This function is useful to parse lists of phandles and their arguments.Returns 0 on success and fills out_args, on error returns appropriate errnovalue. The difference between this function andof_parse_phandle_with_args()is that this API remaps a phandle if the node the phandle points to hasa <stem_name>-map property.

Caller is responsible to callof_node_put() on the returned out_args->nppointer.

Example:

phandle1: node1 {    #list-cells = <2>;};phandle2: node2 {    #list-cells = <1>;};phandle3: node3 {    #list-cells = <1>;    list-map = <0 &phandle2 3>,               <1 &phandle2 2>,               <2 &phandle1 5 1>;    list-map-mask = <0x3>;};node4 {    list = <&phandle1 1 2 &phandle3 0>;};

To get a device_node of thenode2 node you may call this:of_parse_phandle_with_args(node4, “list”, “list”, 1,args);

Parameters

conststructdevice_node*np

pointer to a device tree node containing a list

constchar*list_name

property name that contains a list

constchar*cells_name

property name that specifies phandles’ arguments count

Return

The number of phandle + argument tuples within a property. Itis a typical pattern to encode a list of phandle and variablearguments into a single property. The number of arguments is encodedby a property in the phandle-target node. For example, a gpiosproperty would contain a list of GPIO specifies consisting of aphandle and 1 or more arguments. The number of arguments aredetermined by the #gpio-cells property in the node pointed to by thephandle.

Parameters

structdevice_node*np

Caller’s Device Node

structproperty*prop

Property to add

Parameters

structdevice_node*np

Caller’s Device Node

structproperty*prop

Property to remove

Description

Note that we don’t actually remove it, since we have given outwho-knows-how-many pointers to the data using get-property.Instead we just move the property to the “dead properties”list, so it won’t be found any more.

Parameters

conststructdevice_node*np

Pointer to the given device_node

constchar*stem

Alias stem of the given device_node

Description

The function travels the lookup table to get the alias id for the givendevice_node and alias stem.

Return

The alias id if found.

Parameters

constchar*stem

Alias stem to be examined

Description

The function travels the lookup table to get the highest alias id for thegiven alias stem. It returns the alias id if found.

Parameters

conststructdevice_node*dn

Pointer to device node

char*name

Name to use for preferred console without index. ex. “ttyS”

intindex

Index to use for preferred console.

Description

Check if the given device node matches the stdout-path property in the/chosen node. If it does then register it as the preferred console.

Return

TRUE if console successfully setup. Otherwise return FALSE.

Parameters

conststructdevice_node*np

root complex device node.

u32id

device ID to map.

constchar*map_name

property name of the map to use.

constchar*map_mask_name

optional property name of the mask to use.

structdevice_node**target

optional pointer to a target device node.

u32*id_out

optional pointer to receive the translated ID.

Description

Given a device ID, look up the appropriate implementation-definedplatform ID and/or the target device which receives transactions on thatID, as per the “iommu-map” and “msi-map” bindings. Either oftarget orid_out may be NULL if only the other is required. Iftarget points toa non-NULL device node pointer, only entries targeting that node will bematched; if it points to a NULL value, it will receive the device node ofthe first matching target phandle, with a reference held.

Return

0 on success or a standard error code on failure.

Parameters

structdevice_node*node

Pointer to device node that has been created bykzalloc()

Description

On return the device_node refcount is set to one. Useof_node_put()onnode when done to free the memory allocated for it. If the nodeis NOT a dynamic node the memory will not be freed. The decision ofwhether to free the memory will be done by node->release(), which isof_node_release().

Parameters

constchar*compat

compatible string to look for in root node’s compatible property.

Return

true if the root node has the given value in its compatible property.

Parameters

conststructdevice_node*np

Pointer to device node holding phandle property

constchar*phandle_name

Name of property holding a phandle value

intindex

For properties holding a table of phandles, this is the index intothe table

Return

The device_node pointer with refcount incremented. Useof_node_put() on it when done.

Parameters

conststructdevice_node*np

pointer to a device tree node containing a list

constchar*list_name

property name that contains a list

constchar*cells_name

property name that specifies phandles’ arguments count

intindex

index of a phandle to parse out

structof_phandle_args*out_args

optional pointer to output arguments structure (will be filled)

Description

This function is useful to parse lists of phandles and their arguments.Returns 0 on success and fills out_args, on error returns appropriateerrno value.

Caller is responsible to callof_node_put() on the returned out_args->nppointer.

Example:

phandle1: node1 {    #list-cells = <2>;};phandle2: node2 {    #list-cells = <1>;};node3 {    list = <&phandle1 1 2 &phandle2 3>;};

To get a device_node of thenode2 node you may call this:of_parse_phandle_with_args(node3, “list”, “#list-cells”, 1,args);

Parameters

conststructdevice_node*np

pointer to a device tree node containing a list

constchar*list_name

property name that contains a list

intcell_count

number of argument cells following the phandle

intindex

index of a phandle to parse out

structof_phandle_args*out_args

optional pointer to output arguments structure (will be filled)

Description

This function is useful to parse lists of phandles and their arguments.Returns 0 on success and fills out_args, on error returns appropriateerrno value.

Caller is responsible to callof_node_put() on the returned out_args->nppointer.

Example:

phandle1: node1 {};phandle2: node2 {};node3 {    list = <&phandle1 0 2 &phandle2 2 3>;};

To get a device_node of thenode2 node you may call this:of_parse_phandle_with_fixed_args(node3, “list”, 2, 1,args);

Parameters

conststructdevice_node*np

pointer to a device tree node containing a list

constchar*list_name

property name that contains a list

constchar*cells_name

property name that specifies phandles’ arguments count

intindex

index of a phandle to parse out

structof_phandle_args*out_args

optional pointer to output arguments structure (will be filled)

Description

Same asof_parse_phandle_with_args() except that if the cells_name propertyis not found, cell_count of 0 is assumed.

This is used to useful, if you have a phandle which didn’t have argumentsbefore and thus doesn’t have a ‘#*-cells’ property but is now migrated tohaving arguments while retaining backwards compatibility.

Parameters

conststructof_phandle_args*a1

First of_phandle_args to compare

conststructof_phandle_args*a2

Second of_phandle_args to compare

Return

True if a1 and a2 are the same (same node pointer, same phandleargs), false otherwise.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

Description

Search for a property in a device node and count the number of u8 elementsin it.

Return

The number of elements on success, -EINVAL if the property doesnot exist or its length does not match a multiple of u8 and -ENODATA if theproperty does not have a value.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

Description

Search for a property in a device node and count the number of u16 elementsin it.

Return

The number of elements on success, -EINVAL if the property doesnot exist or its length does not match a multiple of u16 and -ENODATA if theproperty does not have a value.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

Description

Search for a property in a device node and count the number of u32 elementsin it.

Return

The number of elements on success, -EINVAL if the property doesnot exist or its length does not match a multiple of u32 and -ENODATA if theproperty does not have a value.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

Description

Search for a property in a device node and count the number of u64 elementsin it.

Return

The number of elements on success, -EINVAL if the property doesnot exist or its length does not match a multiple of u64 and -ENODATA if theproperty does not have a value.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

constchar**out_strs

output array of string pointers.

size_tsz

number of array elements to read.

Description

Search for a property in a device tree node and retrieve a list ofterminated string values (pointer to data, not a copy) in that property.

Return

Ifout_strs is NULL, the number of strings in the property is returned.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

Description

Search for a property in a device tree node and retrieve the number of nullterminated string contain in it.

Return

The number of strings on success, -EINVAL if the property does notexist, -ENODATA if property does not have a value, and -EILSEQ if the stringis not null-terminated within the length of the property data.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

intindex

index of the string in the list of strings

constchar**output

pointer to null terminated return string, modified only ifreturn value is 0.

Description

Search for a property in a device tree node and retrieve a nullterminated string value (pointer to data, not a copy) in the list of stringscontained in that property.

The out_string pointer is modified only if a valid string can be decoded.

Return

0 on success, -EINVAL if the property does not exist, -ENODATA ifproperty does not have a value, and -EILSEQ if the string is notnull-terminated within the length of the property data.

Parameters

conststructdevice_node*np

device node to search for the property.

constchar*propname

name of the property to be searched.

Description

Test for a property present in a device node.

Return

true if the property exists false otherwise.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u8*out_values

pointer to return value, modified only if return value is 0.

size_tsz

number of array elements to read

Description

Search for a property in a device node and read 8-bit value(s) fromit.

dts entry of array should be like:

property=/bits/8<0x500x600x70>;

The out_values is modified only if a valid u8 value can be decoded.

Return

0 on success, -EINVAL if the property does not exist,-ENODATA if property does not have a value, and -EOVERFLOW if theproperty data isn’t large enough.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u16*out_values

pointer to return value, modified only if return value is 0.

size_tsz

number of array elements to read

Description

Search for a property in a device node and read 16-bit value(s) fromit.

dts entry of array should be like:

property=/bits/16<0x50000x60000x7000>;

The out_values is modified only if a valid u16 value can be decoded.

Return

0 on success, -EINVAL if the property does not exist,-ENODATA if property does not have a value, and -EOVERFLOW if theproperty data isn’t large enough.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u32*out_values

pointer to return value, modified only if return value is 0.

size_tsz

number of array elements to read

Description

Search for a property in a device node and read 32-bit value(s) fromit.

The out_values is modified only if a valid u32 value can be decoded.

Return

0 on success, -EINVAL if the property does not exist,-ENODATA if property does not have a value, and -EOVERFLOW if theproperty data isn’t large enough.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u64*out_values

pointer to return value, modified only if return value is 0.

size_tsz

number of array elements to read

Description

Search for a property in a device node and read 64-bit value(s) fromit.

The out_values is modified only if a valid u64 value can be decoded.

Return

0 on success, -EINVAL if the property does not exist,-ENODATA if property does not have a value, and -EOVERFLOW if theproperty data isn’t large enough.

Definition:

struct of_changeset_entry {    struct list_head node;    unsigned long action;    struct device_node *np;    struct property *prop;    struct property *old_prop;};

Members

node

list_head for the log list

action

notifier action

np

pointer to the device node affected

prop

pointer to the property affected

old_prop

hold a pointer to the original property

Definition:

struct of_changeset {    struct list_head entries;};

Members

entries

list_head for the changeset entries

Parameters

conststructdevice_node*np

Pointer to the given device_node

Return

true if present false otherwise

Parameters

void

no arguments

Return

True if a DTB has been populated by the bootloader and it isn’t theempty builtin one. False otherwise.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

Description

Search for a boolean property in a device node. Usage on non-booleanproperty types is deprecated.

Return

true if the property exists false otherwise.

Parameters

conststructdevice_node*node

pointer to device_node containing graph port

Return

True ifnode has a port or ports (with a port) sub-node,false otherwise.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

intelem_size

size of the individual element

Description

Search for a property in a device node and count the number of elements ofsize elem_size in it.

Return

The number of elements on sucess, -EINVAL if the property does notexist or its length does not match a multiple of elem_size and -ENODATA ifthe property does not have a value.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u32index

index of the u8 in the list of values

u8*out_value

pointer to return value, modified only if no error.

Description

Search for a property in a device node and read nth 8-bit value fromit.

The out_value is modified only if a valid u8 value can be decoded.

Return

0 on success, -EINVAL if the property does not exist,-ENODATA if property does not have a value, and -EOVERFLOW if theproperty data isn’t large enough.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u32index

index of the u16 in the list of values

u16*out_value

pointer to return value, modified only if no error.

Description

Search for a property in a device node and read nth 16-bit value fromit.

The out_value is modified only if a valid u16 value can be decoded.

Return

0 on success, -EINVAL if the property does not exist,-ENODATA if property does not have a value, and -EOVERFLOW if theproperty data isn’t large enough.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u32index

index of the u32 in the list of values

u32*out_value

pointer to return value, modified only if no error.

Description

Search for a property in a device node and read nth 32-bit value fromit.

The out_value is modified only if a valid u32 value can be decoded.

Return

0 on success, -EINVAL if the property does not exist,-ENODATA if property does not have a value, and -EOVERFLOW if theproperty data isn’t large enough.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u32index

index of the u64 in the list of values

u64*out_value

pointer to return value, modified only if no error.

Description

Search for a property in a device node and read nth 64-bit value fromit.

The out_value is modified only if a valid u64 value can be decoded.

Return

0 on success, -EINVAL if the property does not exist,-ENODATA if property does not have a value, and -EOVERFLOW if theproperty data isn’t large enough.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u8*out_values

pointer to found values.

size_tsz_min

minimum number of array elements to read

size_tsz_max

maximum number of array elements to read, if zero there is noupper limit on the number of elements in the dts entry but onlysz_min will be read.

Description

Search for a property in a device node and read 8-bit value(s) fromit.

dts entry of array should be like:

property=/bits/8<0x500x600x70>;

The out_values is modified only if a valid u8 value can be decoded.

Return

The number of elements read on success, -EINVAL if the propertydoes not exist, -ENODATA if property does not have a value, and -EOVERFLOWif the property data is smaller than sz_min or longer than sz_max.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u16*out_values

pointer to found values.

size_tsz_min

minimum number of array elements to read

size_tsz_max

maximum number of array elements to read, if zero there is noupper limit on the number of elements in the dts entry but onlysz_min will be read.

Description

Search for a property in a device node and read 16-bit value(s) fromit.

dts entry of array should be like:

property=/bits/16<0x50000x60000x7000>;

The out_values is modified only if a valid u16 value can be decoded.

Return

The number of elements read on success, -EINVAL if the propertydoes not exist, -ENODATA if property does not have a value, and -EOVERFLOWif the property data is smaller than sz_min or longer than sz_max.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u32*out_values

pointer to return found values.

size_tsz_min

minimum number of array elements to read

size_tsz_max

maximum number of array elements to read, if zero there is noupper limit on the number of elements in the dts entry but onlysz_min will be read.

Description

Search for a property in a device node and read 32-bit value(s) fromit.

The out_values is modified only if a valid u32 value can be decoded.

Return

The number of elements read on success, -EINVAL if the propertydoes not exist, -ENODATA if property does not have a value, and -EOVERFLOWif the property data is smaller than sz_min or longer than sz_max.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u64*out_value

pointer to return value, modified only if return value is 0.

Description

Search for a property in a device node and read a 64-bit value fromit.

The out_value is modified only if a valid u64 value can be decoded.

Return

0 on success, -EINVAL if the property does not exist,-ENODATA if property does not have a value, and -EOVERFLOW if theproperty data isn’t large enough.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

u64*out_values

pointer to found values.

size_tsz_min

minimum number of array elements to read

size_tsz_max

maximum number of array elements to read, if zero there is noupper limit on the number of elements in the dts entry but onlysz_min will be read.

Description

Search for a property in a device node and read 64-bit value(s) fromit.

The out_values is modified only if a valid u64 value can be decoded.

Return

The number of elements read on success, -EINVAL if the propertydoes not exist, -ENODATA if property does not have a value, and -EOVERFLOWif the property data is smaller than sz_min or longer than sz_max.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

constchar**out_string

pointer to null terminated return string, modified only ifreturn value is 0.

Description

Search for a property in a device tree node and retrieve a nullterminated string value (pointer to data, not a copy).

Note that the empty string “” has length of 1, thus -ENODATA cannotbe interpreted as an empty string.

The out_string pointer is modified only if a valid string can be decoded.

Return

0 on success, -EINVAL if the property does not exist, -ENODATA ifproperty does not have a value, and -EILSEQ if the string is notnull-terminated within the length of the property data.

Parameters

conststructdevice_node*np

pointer to the node containing the string list property

constchar*propname

string list property name

constchar*string

pointer to the string to search for in the string list

Description

Search for an exact match of string in a device node property which is astring of lists.

Return

the index of the first occurrence of the string on success, -EINVALif the property does not exist, -ENODATA if the property does not have avalue, and -EILSEQ if the string is not null-terminated within the length ofthe property data.

Parameters

conststructdevice_node*np

device node from which the property value is to be read.

constchar*propname

name of the property to be searched.

constchar**out_strs

output array of string pointers.

size_tsz

number of array elements to read.

intskip

Number of strings to skip over at beginning of list.

Description

Don’t call this function directly. It is a utility helper for theof_property_read_string*() family of functions.

Parameters

conststructdevice_node*node

pointer to endpoint device_node

structof_endpoint*endpoint

pointer to the OF endpoint data structure

Description

The caller should hold a reference tonode.

Parameters

structdevice_node*parent

pointer to the parent device node

u32id

id of the port

Return

A ‘port’ node pointer with refcount incremented. The callerhas to useof_node_put() on it when done.

Parameters

conststructdevice_node*parent

pointer to the parent device node, or parent ports node

structdevice_node*prev

previous port node, or NULL to get first

Description

Parent device node can be used asparent whether device node has ports nodeor not. It will work same as ports**0** node.

Return

A ‘port’ node pointer with refcount incremented. Refcountof the passedprev node is decremented.

Parameters

conststructdevice_node*port

pointer to the target port node

structdevice_node*prev

previous endpoint node, or NULL to get first

Return

An ‘endpoint’ node pointer with refcount incremented. Refcountof the passedprev node is decremented.

Parameters

conststructdevice_node*parent

pointer to the parent device node

structdevice_node*prev

previous endpoint node, or NULL to get first

Return

An ‘endpoint’ node pointer with refcount incremented. Refcountof the passedprev node is decremented.

Parameters

conststructdevice_node*parent

pointer to the parent device node

intport_reg

identifier (value of reg property) of the parent port node

intreg

identifier (value of reg property) of the endpoint node

Return

An ‘endpoint’ node pointer which is identified by reg and at the sameis the child of a port node identified by port_reg. reg and port_reg areignored when they are -1. Useof_node_put() on the pointer when done.

Parameters

conststructdevice_node*node

pointer to a local endpoint device_node

Return

Remote endpoint node associated with remote endpoint node linkedtonode. Useof_node_put() on it when done.

Parameters

structdevice_node*node

pointer to a local endpoint device_node

Return

device node associated with endpoint node linkedtonode. Useof_node_put() on it when done.

Parameters

conststructdevice_node*node

pointer to a local endpoint device_node

Return

Remote device node associated with remote endpoint node linkedtonode. Useof_node_put() on it when done.

Parameters

conststructdevice_node*node

pointer to a local endpoint device_node

Return

Remote port node associated with remote endpoint node linkedtonode. Useof_node_put() on it when done.

Parameters

conststructdevice_node*np

parent device node containing ports and endpoints

Return

count of endpoint of this device node

Parameters

structdevice_node*np

pointer to the device or ports node

Return

count of port of this device or ports node

Parameters

conststructdevice_node*node

pointer to parent device_node containing graph port/endpoint

u32port

identifier (value of reg property) of the parent port node

u32endpoint

identifier (value of reg property) of the endpoint node

Return

Remote device node associated with remote endpoint node linkedtonode. Useof_node_put() on it when done.

Definition:

struct of_endpoint {    unsigned int port;    unsigned int id;    const struct device_node *local_node;};

Members

port

identifier (value of reg property) of a port this endpoint belongs to

id

identifier (value of reg property) of this endpoint

local_node

pointer to device_node of this endpoint

Parameters

parent

parent device node containing ports and endpoints

child

loop variable pointing to the current endpoint node

Description

When breaking out of the loop, of_node_put(child) has to be called manually.

Parameters

parent

parent device or ports node containing port

child

loop variable pointing to the current port node

Description

When breaking out of the loop, and continue to use thechild, you need touse return_ptr(child) or no_free_ptr(child) not to call__free() for it.

Parameters

parent

parent port node

child

loop variable pointing to the current endpoint node

Description

When breaking out of the loop, and continue to use thechild, you need touse return_ptr(child) or no_free_ptr(child) not to call__free() for it.

Parameters

structdevice_node*dev

device tree node for which to translate

const__be32*prop

pointer into array of cells

phys_addr_t*start

return value for the start of the DMA range

size_t*length

return value for the length of the DMA range

Description

Returns a pointer to the cell immediately following the translated DMA region.

Parameters

structdevice_node*np

device tree node for which to retrieve “reg” from

intidx

“reg” entry index to read

u64*addr

return value for the untranslated address

u64*size

return value for the entry size

Description

Returns -EINVAL if “reg” is not found. Returns 0 on success with addr andsize values filled in.

Parameters

structdevice_node*np

device node

Description

It returns true if “dma-coherent” property was foundfor this device in the DT, or if DMA is coherent bydefault for OF devices on the current platform and no“dma-noncoherent” property was found for this device.

Parameters

structdevice_node*dev

Caller’s Device Node

intindex

Index into the array

structresource*r

Pointer to resource array

Description

Returns -EINVAL if the range cannot be converted to resource.

Note that if your address is a PIO address, the conversion will fail ifthe physical address can’t be internally converted to an IO token withpci_address_to_pio(), that is because it’s either called too early or itcan’t be matched to any host bridge IO space

Parameters

structdevice_node*np

the device whose io range will be mapped

intindex

index of the io range

Description

Returns a pointer to the mapped memory

Parameters

structdevice_node*dev

Device node of the device whose interrupt is to be mapped

intindex

Index of the interrupt to map

Description

This function is a wrapper that chainsof_irq_parse_one() andirq_create_of_mapping() to make things easier to callers

Parameters

structdevice_node*child

pointer to device node

Return

A pointer to the interrupt parent node with refcount increasedor NULL if the interrupt parent could not be determined.

Parameters

const__be32*addr

address specifier (start of “reg” property of the device) in be32 format

structof_phandle_args*out_irq

structure of_phandle_args updated by this function

Description

This function is a low-level interrupt tree walking function. Itcan be used to do a partial walk with synthesized reg and interruptsproperties, for example when resolving PCI interrupts when no devicenode exist for the parent. It takes an interrupt specifier structure asinput, walks the tree looking for any interrupt-map properties, translatesthe specifier for each map, and then returns the translated map.

Return

0 on success and a negative number on error

Note

refcount of nodeout_irq->np is increased by 1 on success.

Parameters

structdevice_node*device

the device whose interrupt is to be resolved

intindex

index of the interrupt to resolve

structof_phandle_args*out_irq

structure of_phandle_args filled by this function

Description

This function resolves an interrupt for a node by walking the interrupt tree,finding which interrupt controller node it is attached to, and returning theinterrupt specifier that can be used to retrieve a Linux IRQ number.

Note

refcount of nodeout_irq->np is increased by 1 on success.

Parameters

structdevice_node*dev

pointer to device tree node

intindex

zero-based index of the irq

structresource*r

pointer to resource structure to return result into.

Parameters

structdevice_node*dev

pointer to device tree node

intindex

zero-based index of the IRQ

Return

Linux IRQ number on success, or 0 on the IRQ mapping failure, or-EPROBE_DEFER if the IRQ domain is not yet created, or error code in caseof any other failure.

Parameters

structdevice_node*dev

pointer to device tree node

constchar*name

IRQ name

Return

Linux IRQ number on success, or 0 on the IRQ mapping failure, or-EPROBE_DEFER if the IRQ domain is not yet created, or error code in caseof any other failure.

Parameters

structdevice_node*dev

pointer to device tree node

Parameters

structdevice_node*dev

pointer to device tree node

structresource*res

array of resources to fill in

intnr_irqs

the number of IRQs (and upper bound for num ofres elements)

Return

The size of the filled in table (up tonr_irqs).

Parameters

structdevice*dev

device for which the mapping is to be done.

structdevice_node**msi_np

Pointer to target MSI controller node

u32id_in

Device ID.

Description

Walk up the device hierarchy looking for devices with a “msi-map”or “msi-parent” property. If found, apply the mapping toid_in.Ifmsi_np points to a non-NULL device node pointer, only entries targetingthat node will be matched; if it points to a NULL value, it will receive thedevice node of the first matching target phandle, with a reference held.

Return

The mapped MSI id.

Parameters

structdevice*dev

device for which the domain is requested

conststructdevice_node*np

device node fordev

enumirq_domain_bus_tokentoken

bus type for this domain

Description

Parse the msi-parent property and returns the corresponding MSI domain.

Return

the MSI domain for this device (or NULL on failure).

Parameters

structdevice*dev

device structure to associate with an MSI irq domain

conststructdevice_node*np

device node for that device

Parameters

constunsignedlong*blob

Flat device tree blob

structdevice_node*dad

Parent device node

structdevice_node**mynodes

The device tree created by the call

Description

unflattens the device-tree passed by the firmware, creating thetree ofstructdevice_node. It also fills the “name” and “type”pointers of the nodes so the normal device-tree walking functionscan be used.

Return

NULL on failure or the memory chunk containing the unflatteneddevice tree on success.

Parameters

structdevice*dev

the device structure to match against

conststructdevice_driver*drv

the device_driver structure to test

Parameters

conststructof_device_id*matches

array of of_device_id match structures to search in

conststructdevice*dev

the OF device structure to match against

Description

Used by a driver to check whether an platform_device present in thesystem is in its list of supported devices.

Parameters

structdevice*dev

Device to apply DMA configuration

structdevice_node*np

Pointer to OF node having DMA configuration

boolforce_dma

Whether device is to be set up byof_dma_configure() even ifDMA capability is not explicitly described by firmware.

constu32*id

Optional const pointer value input id

Description

Try to get devices’s DMA configuration from DT and update itaccordingly.

If platform code needs to use its own special DMA configuration, itcan use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE eventsto fix up DMA configuration.

Parameters

structdevice*dev

Calling device

char*str

Modalias string

ssize_tlen

Size ofstr

Parameters

conststructdevice*dev

Device to display the uevent information for

structkobj_uevent_env*env

Kernel object’s userspace event reference to fill up

Parameters

structdevice*dev

pointer to device structure that is linked to a device tree node

Description

This routine will first try using the translated bus address toderive a unique name. If it cannot, then it will prepend names fromparent nodes until a unique name can be derived.

Definition:

struct of_dev_auxdata {    char *compatible;    resource_size_t phys_addr;    char *name;    void *platform_data;};

Members

compatible

compatible value of node to match against node

phys_addr

Start address of registers to match against node

name

Name to assign for matching nodes

platform_data

platform_data to assign for matching nodes

Parameters

structdevice_node*np

Pointer to device tree node

Description

Takes a reference to the embeddedstructdevice which needs to be droppedafter use.

Return

platform_device pointer, or NULL if not found

Parameters

structdevice_node*np

device node to assign to device

constchar*bus_id

Name to assign to the device. May be null to use default name.

structdevice*parent

Parent device.

Parameters

structdevice_node*np

pointer to node to create device for

constchar*bus_id

name to assign device

structdevice*parent

Linux device model parent device.

Return

Pointer to created platform device, or NULL if a device was notregistered. Unavailable devices will not get registered.

Parameters

structdevice_node*root

parent of the first level to probe or NULL for the root of the tree

conststructof_device_id*matches

match table for bus nodes

structdevice*parent

parent to hook devices from, NULL for toplevel

Description

Note that children of the provided root are not instantiated as devicesunless the specified root itself matches the bus list and is not NULL.

Parameters

structdevice_node*root

parent of the first level to probe or NULL for the root of the tree

conststructof_device_id*matches

match table, NULL to use the default

conststructof_dev_auxdata*lookup

auxdata table for matching id and platform_data with device nodes

structdevice*parent

parent to hook devices from, NULL for toplevel

Description

Similar toof_platform_bus_probe(), this function walks the device treeand creates devices from nodes. It differs in that it follows the modernconvention of requiring all device nodes to have a ‘compatible’ property,and it is suitable for creating devices which are children of the rootnode (of_platform_bus_probe will only create children of the root whichare selected by thematches argument).

New board support should be using this function instead ofof_platform_bus_probe().

Return

0 on success, < 0 on failure.

Parameters

structdevice*parent

device which children will be removed

Description

Complementary toof_platform_populate(), this function removes childrenof the given device (and, recursively, their children) that have beencreated from their respective device tree nodes (and only those,leaving others - eg. manually created - unharmed).