summaryrefslogtreecommitdiffstats
path: root/drivers/base/swnode.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--drivers/base/swnode.c1177
1 files changed, 1177 insertions, 0 deletions
diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
new file mode 100644
index 000000000..44153caa8
--- /dev/null
+++ b/drivers/base/swnode.c
@@ -0,0 +1,1177 @@
+// 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;
+
+ 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_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);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-27 11:02:48 +0000