// SPDX-License-Identifier: GPL-2.0
/*
* Software nodes for the firmware node framework.
*
* Copyright (C) 2018, Intel Corporation
* Author: Heikki Krogerus <[email protected]>
*/
#include <linux/container_of.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/idr.h>
#include <linux/init.h>
#include <linux/kobject.h>
#include <linux/kstrtox.h>
#include <linux/list.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/sysfs.h>
#include <linux/types.h>
#include "base.h"
struct swnode {
struct kobject kobj;
struct fwnode_handle fwnode;
const struct software_node *node;
int id;
/* hierarchy */
struct ida child_ids;
struct list_head entry;
struct list_head children;
struct swnode *parent;
unsigned int allocated:1;
unsigned int managed:1;
};
static DEFINE_IDA(swnode_root_ids);
static struct kset *swnode_kset;
#define kobj_to_swnode(_kobj_) container_of(_kobj_, struct swnode, kobj)
static const struct fwnode_operations software_node_ops;
bool is_software_node(const struct fwnode_handle *fwnode)
{
return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &software_node_ops;
}
EXPORT_SYMBOL_GPL(is_software_node);
#define to_swnode(__fwnode) \
({ \
typeof(__fwnode) __to_swnode_fwnode = __fwnode; \
\
is_software_node(__to_swnode_fwnode) ? \
container_of(__to_swnode_fwnode, \
struct swnode, fwnode) : NULL; \
})
static inline struct swnode *dev_to_swnode(struct device *dev)
{
struct fwnode_handle *fwnode = dev_fwnode(dev);
if (!fwnode)
return NULL;
if (!is_software_node(fwnode))
fwnode = fwnode->secondary;
return to_swnode(fwnode);
}
static struct swnode *
software_node_to_swnode(const struct software_node *node)
{
struct swnode *swnode = NULL;
struct kobject *k;
if (!node)
return NULL;
spin_lock(&swnode_kset->list_lock);
list_for_each_entry(k, &swnode_kset->list, entry) {
swnode = kobj_to_swnode(k);
if (swnode->node == node)
break;
swnode = NULL;
}
spin_unlock(&swnode_kset->list_lock);
return swnode;
}
const struct software_node *to_software_node(const struct fwnode_handle *fwnode)
{
const struct swnode *swnode = to_swnode(fwnode);
return swnode ? swnode->node : NULL;
}
EXPORT_SYMBOL_GPL(to_software_node);
struct fwnode_handle *software_node_fwnode(const struct software_node *node)
{
struct swnode *swnode = software_node_to_swnode(node);
return swnode ? &swnode->fwnode : NULL;
}
EXPORT_SYMBOL_GPL(software_node_fwnode);
/* -------------------------------------------------------------------------- */
/* property_entry processing */
static const struct property_entry *
property_entry_get(const struct property_entry *prop, const char *name)
{
if (!prop)
return NULL;
for (; prop->name; prop++)
if (!strcmp(name, prop->name))
return prop;
return NULL;
}
static const void *property_get_pointer(const struct property_entry *prop)
{
if (!prop->length)
return NULL;
return prop->is_inline ? &prop->value : prop->pointer;
}
static const void *property_entry_find(const struct property_entry *props,
const char *propname, size_t length)
{
const struct property_entry *prop;
const void *pointer;
prop = property_entry_get(props, propname);
if (!prop)
return ERR_PTR(-EINVAL);
pointer = property_get_pointer(prop);
if (!pointer)
return ERR_PTR(-ENODATA);
if (length > prop->length)
return ERR_PTR(-EOVERFLOW);
return pointer;
}
static int
property_entry_count_elems_of_size(const struct property_entry *props,
const char *propname, size_t length)
{
const struct property_entry *prop;
prop = property_entry_get(props, propname);
if (!prop)
return -EINVAL;
return prop->length / length;
}
static int property_entry_read_int_array(const struct property_entry *props,
const char *name,
unsigned int elem_size, void *val,
size_t nval)
{
const void *pointer;
size_t length;
if (!val)
return property_entry_count_elems_of_size(props, name,
elem_size);
if (!is_power_of_2(elem_size) || elem_size > sizeof(u64))
return -ENXIO;
length = nval * elem_size;
pointer = property_entry_find(props, name, length);
if (IS_ERR(pointer))
return PTR_ERR(pointer);
memcpy(val, pointer, length);
return 0;
}
static int property_entry_read_string_array(const struct property_entry *props,
const char *propname,
const char **strings, size_t nval)
{
const void *pointer;
size_t length;
int array_len;
/* Find out the array length. */
array_len = property_entry_count_elems_of_size(props, propname,
sizeof(const char *));
if (array_len < 0)
return array_len;
/* Return how many there are if strings is NULL. */
if (!strings)
return array_len;
array_len = min_t(size_t, nval, array_len);
length = array_len * sizeof(*strings);
pointer = property_entry_find(props, propname, length);
if (IS_ERR(pointer))
return PTR_ERR(pointer);
memcpy(strings, pointer, length);
return array_len;
}
static void property_entry_free_data(const struct property_entry *p)
{
const char * const *src_str;
size_t i, nval;
if (p->type == DEV_PROP_STRING) {
src_str = property_get_pointer(p);
nval = p->length / sizeof(*src_str);
for (i = 0; i < nval; i++)
kfree(src_str[i]);
}
if (!p->is_inline)
kfree(p->pointer);
kfree(p->name);
}
static bool property_copy_string_array(const char **dst_ptr,
const char * const *src_ptr,
size_t nval)
{
int i;
for (i = 0; i < nval; i++) {
dst_ptr[i] = kstrdup(src_ptr[i], GFP_KERNEL);
if (!dst_ptr[i] && src_ptr[i]) {
while (--i >= 0)
kfree(dst_ptr[i]);
return false;
}
}
return true;
}
static int property_entry_copy_data(struct property_entry *dst,
const struct property_entry *src)
{
const void *pointer = property_get_pointer(src);
void *dst_ptr;
size_t nval;
/*
* Properties with no data should not be marked as stored
* out of line.
*/
if (!src->is_inline && !src->length)
return -ENODATA;
/*
* Reference properties are never stored inline as
* they are too big.
*/
if (src->type == DEV_PROP_REF && src->is_inline)
return -EINVAL;
if (src->length <= sizeof(dst->value)) {
dst_ptr = &dst->value;
dst->is_inline = true;
} else {
dst_ptr = kmalloc(src->length, GFP_KERNEL);
if (!dst_ptr)
return -ENOMEM;
dst->pointer = dst_ptr;
}
if (src->type == DEV_PROP_STRING) {
nval = src->length / sizeof(const char *);
if (!property_copy_string_array(dst_ptr, pointer, nval)) {
if (!dst->is_inline)
kfree(dst->pointer);
return -ENOMEM;
}
} else {
memcpy(dst_ptr, pointer, src->length);
}
dst->length = src->length;
dst->type = src->type;
dst->name = kstrdup(src->name, GFP_KERNEL);
if (!dst->name) {
property_entry_free_data(dst);
return -ENOMEM;
}
return 0;
}
/**
* property_entries_dup - duplicate array of properties
* @properties: array of properties to copy
*
* This function creates a deep copy of the given NULL-terminated array
* of property entries.
*/
struct property_entry *
property_entries_dup(const struct property_entry *properties)
{
struct property_entry *p;
int i, n = 0;
int ret;
if (!properties)
return NULL;
while (properties[n].name)
n++;
p = kcalloc(n + 1, sizeof(*p), GFP_KERNEL);
if (!p)
return ERR_PTR(-ENOMEM);
for (i = 0; i < n; i++) {
ret = property_entry_copy_data(&p[i], &properties[i]);
if (ret) {
while (--i >= 0)
property_entry_free_data(&p[i]);
kfree(p);
return ERR_PTR(ret);
}
}
return p;
}
EXPORT_SYMBOL_GPL(property_entries_dup);
/**
* property_entries_free - free previously allocated array of properties
* @properties: array of properties to destroy
*
* This function frees given NULL-terminated array of property entries,
* along with their data.
*/
void property_entries_free(const struct property_entry *properties)
{
const struct property_entry *p;
if (!properties)
return;
for (p = properties; p->name; p++)
property_entry_free_data(p);
kfree(properties);
}
EXPORT_SYMBOL_GPL(property_entries_free);
/* -------------------------------------------------------------------------- */
/* fwnode operations */
static struct fwnode_handle *software_node_get(struct fwnode_handle *fwnode)
{
struct swnode *swnode = to_swnode(fwnode);
kobject_get(&swnode->kobj);
return &swnode->fwnode;
}
static void software_node_put(struct fwnode_handle *fwnode)
{
struct swnode *swnode = to_swnode(fwnode);
kobject_put(&swnode->kobj);
}
static bool software_node_property_present(const struct fwnode_handle *fwnode,
const char *propname)
{
struct swnode *swnode = to_swnode(fwnode);
return !!property_entry_get(swnode->node->properties, propname);
}
static int software_node_read_int_array(const struct fwnode_handle *fwnode,
const char *propname,
unsigned int elem_size, void *val,
size_t nval)
{
struct swnode *swnode = to_swnode(fwnode);
return property_entry_read_int_array(swnode->node->properties, propname,
elem_size, val, nval);
}
static int software_node_read_string_array(const struct fwnode_handle *fwnode,
const char *propname,
const char **val, size_t nval)
{
struct swnode *swnode = to_swnode(fwnode);
return property_entry_read_string_array(swnode->node->properties,
propname, val, nval);
}
static const char *
software_node_get_name(const struct fwnode_handle *fwnode)
{
const struct swnode *swnode = to_swnode(fwnode);
return kobject_name(&swnode->kobj);
}
static const char *
software_node_get_name_prefix(const struct fwnode_handle *fwnode)
{
struct fwnode_handle *parent;
const char *prefix;
parent = fwnode_get_parent(fwnode);
if (!parent)
return "";
/* Figure out the prefix from the parents. */
while (is_software_node(parent))
parent = fwnode_get_next_parent(parent);
prefix = fwnode_get_name_prefix(parent);
fwnode_handle_put(parent);
/* Guess something if prefix was NULL. */
return prefix ?: "/";
}
static struct fwnode_handle *
software_node_get_parent(const struct fwnode_handle *fwnode)
{
struct swnode *swnode = to_swnode(fwnode);
if (!swnode || !swnode->parent)
return NULL;
return fwnode_handle_get(&swnode->parent->fwnode);
}
static struct fwnode_handle *
software_node_get_next_child(const struct fwnode_handle *fwnode,
struct fwnode_handle *child)
{
struct swnode *p = to_swnode(fwnode);
struct swnode *c = to_swnode(child);
if (!p || list_empty(&p->children) ||
(c && list_is_last(&c->entry, &p->children))) {
fwnode_handle_put(child);
return NULL;
}
if (c)
c = list_next_entry(c, entry);
else
c = list_first_entry(&p->children, struct swnode, entry);
fwnode_handle_put(child);
return fwnode_handle_get(&c->fwnode);
}
static struct fwnode_handle *
software_node_get_named_child_node(const struct fwnode_handle *fwnode,
const char *childname)
{
struct swnode *swnode = to_swnode(fwnode);
struct swnode *child;
if (!swnode || list_empty(&swnode->children))
return NULL;
list_for_each_entry(child, &swnode->children, entry) {
if (!strcmp(childname, kobject_name(&child->kobj))) {
kobject_get(&child->kobj);
return &child->fwnode;
}
}
return NULL;
}
static int
software_node_get_reference_args(const struct fwnode_handle *fwnode,
const char *propname, const char *nargs_prop,
unsigned int nargs, unsigned int index,
struct fwnode_reference_args *args)
{
struct swnode *swnode = to_swnode(fwnode);
const struct software_node_ref_args *ref_array;
const struct software_node_ref_args *ref;
const struct property_entry *prop;
struct fwnode_handle *refnode;
u32 nargs_prop_val;
int error;
int i;
prop = property_entry_get(swnode->node->properties, propname);
if (!prop)
return -ENOENT;
if (prop->type != DEV_PROP_REF)
return -EINVAL;
/*
* We expect that references are never stored inline, even
* single ones, as they are too big.
*/
if (prop->is_inline)
return -EINVAL;
if (index * sizeof(*ref) >= prop->length)
return -ENOENT;
ref_array = prop->pointer;
ref = &ref_array[index];
refnode = software_node_fwnode(ref->node);
if (!refnode)
return -ENOENT;
if (nargs_prop) {
error = property_entry_read_int_array(ref->node->properties,
nargs_prop, sizeof(u32),
&nargs_prop_val, 1);
if (error)
return error;
nargs = nargs_prop_val;
}
if (nargs > NR_FWNODE_REFERENCE_ARGS)
return -EINVAL;
if (!args)
return 0;
args->fwnode = software_node_get(refnode);
args->nargs = nargs;
for (i = 0; i < nargs; i++)
args->args[i] = ref->args[i];
return 0;
}
static struct fwnode_handle *
swnode_graph_find_next_port(const struct fwnode_handle *parent,
struct fwnode_handle *port)
{
struct fwnode_handle *old = port;
while ((port = software_node_get_next_child(parent, old))) {
/*
* fwnode ports have naming style "port@", so we search for any
* children that follow that convention.
*/
if (!strncmp(to_swnode(port)->node->name, "port@",
strlen("port@")))
return port;
old = port;
}
return NULL;
}
static struct fwnode_handle *
software_node_graph_get_next_endpoint(const struct fwnode_handle *fwnode,
struct fwnode_handle *endpoint)
{
struct swnode *swnode = to_swnode(fwnode);
struct fwnode_handle *parent;
struct fwnode_handle *port;
if (!swnode)
return NULL;
if (endpoint) {
port = software_node_get_parent(endpoint);
parent = software_node_get_parent(port);
} else {
parent = software_node_get_named_child_node(fwnode, "ports");
if (!parent)
parent = software_node_get(&swnode->fwnode);
port = swnode_graph_find_next_port(parent, NULL);
}
for (; port; port = swnode_graph_find_next_port(parent, port)) {
endpoint = software_node_get_next_child(port, endpoint);
if (endpoint) {
fwnode_handle_put(port);
break;
}
}
fwnode_handle_put(parent);
return endpoint;
}
static struct fwnode_handle *
software_node_graph_get_remote_endpoint(const struct fwnode_handle *fwnode)
{
struct swnode *swnode = to_swnode(fwnode);
const struct software_node_ref_args *ref;
const struct property_entry *prop;
if (!swnode)
return NULL;
prop = property_entry_get(swnode->node->properties, "remote-endpoint");
if (!prop || prop->type != DEV_PROP_REF || prop->is_inline)
return NULL;
ref = prop->pointer;
return software_node_get(software_node_fwnode(ref[0].node));
}
static struct fwnode_handle *
software_node_graph_get_port_parent(struct fwnode_handle *fwnode)
{
struct swnode *swnode = to_swnode(fwnode);
swnode = swnode->parent;
if (swnode && !strcmp(swnode->node->name, "ports"))
swnode = swnode->parent;
return swnode ? software_node_get(&swnode->fwnode) : NULL;
}
static int
software_node_graph_parse_endpoint(const struct fwnode_handle *fwnode,
struct fwnode_endpoint *endpoint)
{
struct swnode *swnode = to_swnode(fwnode);
const char *parent_name = swnode->parent->node->name;
int ret;
if (strlen("port@") >= strlen(parent_name) ||
strncmp(parent_name, "port@", strlen("port@")))
return -EINVAL;
/* Ports have naming style "port@n", we need to select the n */
ret = kstrtou32(parent_name + strlen("port@"), 10, &endpoint->port);
if (ret)
return ret;
endpoint->id = swnode->id;
endpoint->local_fwnode = fwnode;
return 0;
}
static const struct fwnode_operations software_node_ops = {
.get = software_node_get,
.put = software_node_put,
.property_present = software_node_property_present,
.property_read_int_array = software_node_read_int_array,
.property_read_string_array = software_node_read_string_array,
.get_name = software_node_get_name,
.get_name_prefix = software_node_get_name_prefix,
.get_parent = software_node_get_parent,
.get_next_child_node = software_node_get_next_child,
.get_named_child_node = software_node_get_named_child_node,
.get_reference_args = software_node_get_reference_args,
.graph_get_next_endpoint = software_node_graph_get_next_endpoint,
.graph_get_remote_endpoint = software_node_graph_get_remote_endpoint,
.graph_get_port_parent = software_node_graph_get_port_parent,
.graph_parse_endpoint = software_node_graph_parse_endpoint,
};
/* -------------------------------------------------------------------------- */
/**
* software_node_find_by_name - Find software node by name
* @parent: Parent of the software node
* @name: Name of the software node
*
* The function will find a node that is child of @parent and that is named
* @name. If no node is found, the function returns NULL.
*
* NOTE: you will need to drop the reference with fwnode_handle_put() after use.
*/
const struct software_node *
software_node_find_by_name(const struct software_node *parent, const char *name)
{
struct swnode *swnode = NULL;
struct kobject *k;
if (!name)
return NULL;
spin_lock(&swnode_kset->list_lock);
list_for_each_entry(k, &swnode_kset->list, entry) {
swnode = kobj_to_swnode(k);
if (parent == swnode->node->parent && swnode->node->name &&
!strcmp(name, swnode->node->name)) {
kobject_get(&swnode->kobj);
break;
}
swnode = NULL;
}
spin_unlock(&swnode_kset->list_lock);
return swnode ? swnode->node : NULL;
}
EXPORT_SYMBOL_GPL(software_node_find_by_name);
static struct software_node *software_node_alloc(const struct property_entry *properties)
{
struct property_entry *props;
struct software_node *node;
props = property_entries_dup(properties);
if (IS_ERR(props))
return ERR_CAST(props);
node = kzalloc(sizeof(*node), GFP_KERNEL);
if (!node) {
property_entries_free(props);
return ERR_PTR(-ENOMEM);
}
node->properties = props;
return node;
}
static void software_node_free(const struct software_node *node)
{
property_entries_free(node->properties);
kfree(node);
}
static void software_node_release(struct kobject *kobj)
{
struct swnode *swnode = kobj_to_swnode(kobj);
if (swnode->parent) {
ida_free(&swnode->parent->child_ids, swnode->id);
list_del(&swnode->entry);
} else {
ida_free(&swnode_root_ids, swnode->id);
}
if (swnode->allocated)
software_node_free(swnode->node);
ida_destroy(&swnode->child_ids);
kfree(swnode);
}
static const struct kobj_type software_node_type = {
.release = software_node_release,
.sysfs_ops = &kobj_sysfs_ops,
};
static struct fwnode_handle *
swnode_register(const struct software_node *node, struct swnode *parent,
unsigned int allocated)
{
struct swnode *swnode;
int ret;
swnode = kzalloc(sizeof(*swnode), GFP_KERNEL);
if (!swnode)
return ERR_PTR(-ENOMEM);
ret = ida_alloc(parent ? &parent->child_ids : &swnode_root_ids,
GFP_KERNEL);
if (ret < 0) {
kfree(swnode);
return ERR_PTR(ret);
}
swnode->id = ret;
swnode->node = node;
swnode->parent = parent;
swnode->kobj.kset = swnode_kset;
fwnode_init(&swnode->fwnode, &software_node_ops);
ida_init(&swnode->child_ids);
INIT_LIST_HEAD(&swnode->entry);
INIT_LIST_HEAD(&swnode->children);
if (node->name)
ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
parent ? &parent->kobj : NULL,
"%s", node->name);
else
ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
parent ? &parent->kobj : NULL,
"node%d", swnode->id);
if (ret) {
kobject_put(&swnode->kobj);
return ERR_PTR(ret);
}
/*
* Assign the flag only in the successful case, so
* the above kobject_put() won't mess up with properties.
*/
swnode->allocated = allocated;
if (parent)
list_add_tail(&swnode->entry, &parent->children);
kobject_uevent(&swnode->kobj, KOBJ_ADD);
return &swnode->fwnode;
}
/**
* software_node_register_node_group - Register a group of software nodes
* @node_group: NULL terminated array of software node pointers to be registered
*
* Register multiple software nodes at once. If any node in the array
* has its .parent pointer set (which can only be to another software_node),
* then its parent **must** have been registered before it is; either outside
* of this function or by ordering the array such that parent comes before
* child.
*/
int software_node_register_node_group(const struct software_node **node_group)
{
unsigned int i;
int ret;
if (!node_group)
return 0;
for (i = 0; node_group[i]; i++) {
ret = software_node_register(node_group[i]);
if (ret) {
software_node_unregister_node_group(node_group);
return ret;
}
}
return 0;
}
EXPORT_SYMBOL_GPL(software_node_register_node_group);
/**
* software_node_unregister_node_group - Unregister a group of software nodes
* @node_group: NULL terminated array of software node pointers to be unregistered
*
* Unregister multiple software nodes at once. If parent pointers are set up
* in any of the software nodes then the array **must** be ordered such that
* parents come before their children.
*
* NOTE: If you are uncertain whether the array is ordered such that
* parents will be unregistered before their children, it is wiser to
* remove the nodes individually, in the correct order (child before
* parent).
*/
void software_node_unregister_node_group(
const struct software_node **node_group)
{
unsigned int i = 0;
if (!node_group)
return;
while (node_group[i])
i++;
while (i--)
software_node_unregister(node_group[i]);
}
EXPORT_SYMBOL_GPL(software_node_unregister_node_group);
/**
* software_node_register - Register static software node
* @node: The software node to be registered
*/
int software_node_register(const struct software_node *node)
{
struct swnode *parent = software_node_to_swnode(node->parent);
if (software_node_to_swnode(node))
return -EEXIST;
if (node->parent && !parent)
return -EINVAL;
return PTR_ERR_OR_ZERO(swnode_register(node, parent, 0));
}
EXPORT_SYMBOL_GPL(software_node_register);
/**
* software_node_unregister - Unregister static software node
* @node: The software node to be unregistered
*/
void software_node_unregister(const struct software_node *node)
{
struct swnode *swnode;
swnode = software_node_to_swnode(node);
if (swnode)
fwnode_remove_software_node(&swnode->fwnode);
}
EXPORT_SYMBOL_GPL(software_node_unregister);
struct fwnode_handle *
fwnode_create_software_node(const struct property_entry *properties,
const struct fwnode_handle *parent)
{
struct fwnode_handle *fwnode;
struct software_node *node;
struct swnode *p;
if (IS_ERR(parent))
return ERR_CAST(parent);
p = to_swnode(parent);
if (parent && !p)
return ERR_PTR(-EINVAL);
node = software_node_alloc(properties);
if (IS_ERR(node))
return ERR_CAST(node);
node->parent = p ? p->node : NULL;
fwnode = swnode_register(node, p, 1);
if (IS_ERR(fwnode))
software_node_free(node);
return fwnode;
}
EXPORT_SYMBOL_GPL(fwnode_create_software_node);
void fwnode_remove_software_node(struct fwnode_handle *fwnode)
{
struct swnode *swnode = to_swnode(fwnode);
if (!swnode)
return;
kobject_put(&swnode->kobj);
}
EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
/**
* device_add_software_node - Assign software node to a device
* @dev: The device the software node is meant for.
* @node: The software node.
*
* This function will make @node the secondary firmware node pointer of @dev. If
* @dev has no primary node, then @node will become the primary node. The
* function will register @node automatically if it wasn't already registered.
*/
int device_add_software_node(struct device *dev, const struct software_node *node)
{
struct swnode *swnode;
int ret;
/* Only one software node per device. */
if (dev_to_swnode(dev))
return -EBUSY;
swnode = software_node_to_swnode(node);
if (swnode) {
kobject_get(&swnode->kobj);
} else {
ret = software_node_register(node);
if (ret)
return ret;
swnode = software_node_to_swnode(node);
}
set_secondary_fwnode(dev, &swnode->fwnode);
/*
* If the device has been fully registered by the time this function is
* called, software_node_notify() must be called separately so that the
* symlinks get created and the reference count of the node is kept in
* balance.
*/
if (device_is_registered(dev))
software_node_notify(dev);
return 0;
}
EXPORT_SYMBOL_GPL(device_add_software_node);
/**
* device_remove_software_node - Remove device's software node
* @dev: The device with the software node.
*
* This function will unregister the software node of @dev.
*/
void device_remove_software_node(struct device *dev)
{
struct swnode *swnode;
swnode = dev_to_swnode(dev);
if (!swnode)
return;
if (device_is_registered(dev))
software_node_notify_remove(dev);
set_secondary_fwnode(dev, NULL);
kobject_put(&swnode->kobj);
}
EXPORT_SYMBOL_GPL(device_remove_software_node);
/**
* device_create_managed_software_node - Create a software node for a device
* @dev: The device the software node is assigned to.
* @properties: Device properties for the software node.
* @parent: Parent of the software node.
*
* Creates a software node as a managed resource for @dev, which means the
* lifetime of the newly created software node is tied to the lifetime of @dev.
* Software nodes created with this function should not be reused or shared
* because of that. The function takes a deep copy of @properties for the
* software node.
*
* Since the new software node is assigned directly to @dev, and since it should
* not be shared, it is not returned to the caller. The function returns 0 on
* success, and errno in case of an error.
*/
int device_create_managed_software_node(struct device *dev,
const struct property_entry *properties,
const struct software_node *parent)
{
struct fwnode_handle *p = software_node_fwnode(parent);
struct fwnode_handle *fwnode;
if (parent && !p)
return -EINVAL;
fwnode = fwnode_create_software_node(properties, p);
if (IS_ERR(fwnode))
return PTR_ERR(fwnode);
to_swnode(fwnode)->managed = true;
set_secondary_fwnode(dev, fwnode);
if (device_is_registered(dev))
software_node_notify(dev);
return 0;
}
EXPORT_SYMBOL_GPL(device_create_managed_software_node);
void software_node_notify(struct device *dev)
{
struct swnode *swnode;
int ret;
swnode = dev_to_swnode(dev);
if (!swnode)
return;
ret = sysfs_create_link(&dev->kobj, &swnode->kobj, "software_node");
if (ret)
return;
ret = sysfs_create_link(&swnode->kobj, &dev->kobj, dev_name(dev));
if (ret) {
sysfs_remove_link(&dev->kobj, "software_node");
return;
}
kobject_get(&swnode->kobj);
}
void software_node_notify_remove(struct device *dev)
{
struct swnode *swnode;
swnode = dev_to_swnode(dev);
if (!swnode)
return;
sysfs_remove_link(&swnode->kobj, dev_name(dev));
sysfs_remove_link(&dev->kobj, "software_node");
kobject_put(&swnode->kobj);
if (swnode->managed) {
set_secondary_fwnode(dev, NULL);
kobject_put(&swnode->kobj);
}
}
static int __init software_node_init(void)
{
swnode_kset = kset_create_and_add("software_nodes", NULL, kernel_kobj);
if (!swnode_kset)
return -ENOMEM;
return 0;
}
postcore_initcall(software_node_init);
static void __exit software_node_exit(void)
{
ida_destroy(&swnode_root_ids);
kset_unregister(swnode_kset);
}
__exitcall(software_node_exit);
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