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- // 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>
- struct swnode {
- int id;
- struct kobject kobj;
- struct fwnode_handle fwnode;
- const struct software_node *node;
- /* hierarchy */
- struct ida child_ids;
- struct list_head entry;
- struct list_head children;
- struct swnode *parent;
- unsigned int allocated: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);
- if (!swnode)
- return "(null)";
- 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;
- if (!swnode)
- return -ENOENT;
- 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;
- args->fwnode = software_node_get(refnode);
- args->nargs = nargs;
- for (i = 0; i < nargs; i++)
- args->args[i] = ref->args[i];
- 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
- };
- /* -------------------------------------------------------------------------- */
- /**
- * 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 int
- software_node_register_properties(struct software_node *node,
- const struct property_entry *properties)
- {
- struct property_entry *props;
- props = property_entries_dup(properties);
- if (IS_ERR(props))
- return PTR_ERR(props);
- node->properties = props;
- return 0;
- }
- 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) {
- property_entries_free(swnode->node->properties);
- kfree(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) {
- ret = -ENOMEM;
- goto out_err;
- }
- ret = ida_simple_get(parent ? &parent->child_ids : &swnode_root_ids,
- 0, 0, GFP_KERNEL);
- if (ret < 0) {
- kfree(swnode);
- goto out_err;
- }
- swnode->id = ret;
- swnode->node = node;
- swnode->parent = parent;
- swnode->allocated = allocated;
- 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);
- }
- if (parent)
- list_add_tail(&swnode->entry, &parent->children);
- kobject_uevent(&swnode->kobj, KOBJ_ADD);
- return &swnode->fwnode;
- out_err:
- if (allocated)
- property_entries_free(node->properties);
- return ERR_PTR(ret);
- }
- /**
- * 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.
- */
- int software_node_register_nodes(const struct software_node *nodes)
- {
- int ret;
- int i;
- for (i = 0; nodes[i].name; i++) {
- ret = software_node_register(&nodes[i]);
- if (ret) {
- software_node_unregister_nodes(nodes);
- return ret;
- }
- }
- return 0;
- }
- 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.
- *
- * NOTE: Be careful using this call if the nodes had parent pointers set up in
- * them before registering. If so, it is wiser to remove the nodes
- * individually, in the correct order (child before parent) instead of relying
- * on the sequential order of the list of nodes in the array.
- */
- void software_node_unregister_nodes(const struct software_node *nodes)
- {
- int i;
- for (i = 0; nodes[i].name; 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.
- */
- 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.
- */
- void software_node_unregister_node_group(const struct software_node **node_group)
- {
- unsigned int i;
- if (!node_group)
- return;
- for (i = 0; node_group[i]; 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 software_node *node;
- struct swnode *p = NULL;
- int ret;
- if (parent) {
- if (IS_ERR(parent))
- return ERR_CAST(parent);
- if (!is_software_node(parent))
- return ERR_PTR(-EINVAL);
- p = to_swnode(parent);
- }
- node = kzalloc(sizeof(*node), GFP_KERNEL);
- if (!node)
- return ERR_PTR(-ENOMEM);
- ret = software_node_register_properties(node, properties);
- if (ret) {
- kfree(node);
- return ERR_PTR(ret);
- }
- node->parent = p ? p->node : NULL;
- return swnode_register(node, p, 1);
- }
- 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, KOBJ_ADD);
- 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(dev, KOBJ_REMOVE);
- set_secondary_fwnode(dev, NULL);
- kobject_put(&swnode->kobj);
- }
- EXPORT_SYMBOL_GPL(device_remove_software_node);
- int software_node_notify(struct device *dev, unsigned long action)
- {
- struct swnode *swnode;
- int ret;
- swnode = dev_to_swnode(dev);
- if (!swnode)
- return 0;
- switch (action) {
- case KOBJ_ADD:
- ret = sysfs_create_link(&dev->kobj, &swnode->kobj, "software_node");
- if (ret)
- break;
- ret = sysfs_create_link(&swnode->kobj, &dev->kobj,
- dev_name(dev));
- if (ret) {
- sysfs_remove_link(&dev->kobj, "software_node");
- break;
- }
- kobject_get(&swnode->kobj);
- break;
- case KOBJ_REMOVE:
- sysfs_remove_link(&swnode->kobj, dev_name(dev));
- sysfs_remove_link(&dev->kobj, "software_node");
- kobject_put(&swnode->kobj);
- break;
- default:
- break;
- }
- return 0;
- }
- 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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