linux/drivers/base/swnode.c
Andy Shevchenko 27e0bcd029 device property: Drop redundant NULL checks
In cases when functions are called via fwnode operations,
we already know that this is software node we are dealing
with, hence no need to check if it's NULL, it can't be,

Reported-by: YE Chengfeng <cyeaa@connect.ust.hk>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211026162954.89811-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26 19:14:01 +02:00

1175 lines
28 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Software nodes for the firmware node framework.
*
* Copyright (C) 2018, Intel Corporation
* Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/property.h>
#include <linux/slab.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(swnode->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;
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_simple_remove(&swnode->parent->child_ids, swnode->id);
list_del(&swnode->entry);
} else {
ida_simple_remove(&swnode_root_ids, swnode->id);
}
if (swnode->allocated)
software_node_free(swnode->node);
ida_destroy(&swnode->child_ids);
kfree(swnode);
}
static 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_simple_get(parent ? &parent->child_ids : &swnode_root_ids,
0, 0, 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_nodes - Register an array of software nodes
* @nodes: Zero terminated array of software nodes 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_nodes(const struct software_node *nodes)
{
int ret;
int i;
for (i = 0; nodes[i].name; i++) {
const struct software_node *parent = nodes[i].parent;
if (parent && !software_node_to_swnode(parent)) {
ret = -EINVAL;
goto err_unregister_nodes;
}
ret = software_node_register(&nodes[i]);
if (ret)
goto err_unregister_nodes;
}
return 0;
err_unregister_nodes:
software_node_unregister_nodes(nodes);
return ret;
}
EXPORT_SYMBOL_GPL(software_node_register_nodes);
/**
* software_node_unregister_nodes - Unregister an array of software nodes
* @nodes: Zero terminated array of software nodes 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_nodes(const struct software_node *nodes)
{
unsigned int i = 0;
while (nodes[i].name)
i++;
while (i--)
software_node_unregister(&nodes[i]);
}
EXPORT_SYMBOL_GPL(software_node_unregister_nodes);
/**
* 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);