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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // 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(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 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);

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