1 // SPDX-License-Identifier: GPL-2.0
3 * Software nodes for the firmware node framework.
5 * Copyright (C) 2018, Intel Corporation
6 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
9 #include <linux/device.h>
10 #include <linux/kernel.h>
11 #include <linux/property.h>
12 #include <linux/slab.h>
17 struct fwnode_handle fwnode;
18 const struct software_node *node;
22 struct list_head entry;
23 struct list_head children;
24 struct swnode *parent;
26 unsigned int allocated:1;
29 static DEFINE_IDA(swnode_root_ids);
30 static struct kset *swnode_kset;
32 #define kobj_to_swnode(_kobj_) container_of(_kobj_, struct swnode, kobj)
34 static const struct fwnode_operations software_node_ops;
36 bool is_software_node(const struct fwnode_handle *fwnode)
38 return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &software_node_ops;
40 EXPORT_SYMBOL_GPL(is_software_node);
42 #define to_swnode(__fwnode) \
44 typeof(__fwnode) __to_swnode_fwnode = __fwnode; \
46 is_software_node(__to_swnode_fwnode) ? \
47 container_of(__to_swnode_fwnode, \
48 struct swnode, fwnode) : NULL; \
51 static struct swnode *
52 software_node_to_swnode(const struct software_node *node)
54 struct swnode *swnode = NULL;
60 spin_lock(&swnode_kset->list_lock);
62 list_for_each_entry(k, &swnode_kset->list, entry) {
63 swnode = kobj_to_swnode(k);
64 if (swnode->node == node)
69 spin_unlock(&swnode_kset->list_lock);
74 const struct software_node *to_software_node(const struct fwnode_handle *fwnode)
76 const struct swnode *swnode = to_swnode(fwnode);
78 return swnode ? swnode->node : NULL;
80 EXPORT_SYMBOL_GPL(to_software_node);
82 struct fwnode_handle *software_node_fwnode(const struct software_node *node)
84 struct swnode *swnode = software_node_to_swnode(node);
86 return swnode ? &swnode->fwnode : NULL;
88 EXPORT_SYMBOL_GPL(software_node_fwnode);
90 /* -------------------------------------------------------------------------- */
91 /* property_entry processing */
93 static const struct property_entry *
94 property_entry_get(const struct property_entry *prop, const char *name)
99 for (; prop->name; prop++)
100 if (!strcmp(name, prop->name))
106 static const void *property_get_pointer(const struct property_entry *prop)
111 return prop->is_inline ? &prop->value : prop->pointer;
114 static const void *property_entry_find(const struct property_entry *props,
115 const char *propname, size_t length)
117 const struct property_entry *prop;
120 prop = property_entry_get(props, propname);
122 return ERR_PTR(-EINVAL);
123 pointer = property_get_pointer(prop);
125 return ERR_PTR(-ENODATA);
126 if (length > prop->length)
127 return ERR_PTR(-EOVERFLOW);
132 property_entry_count_elems_of_size(const struct property_entry *props,
133 const char *propname, size_t length)
135 const struct property_entry *prop;
137 prop = property_entry_get(props, propname);
141 return prop->length / length;
144 static int property_entry_read_int_array(const struct property_entry *props,
146 unsigned int elem_size, void *val,
153 return property_entry_count_elems_of_size(props, name,
156 if (!is_power_of_2(elem_size) || elem_size > sizeof(u64))
159 length = nval * elem_size;
161 pointer = property_entry_find(props, name, length);
163 return PTR_ERR(pointer);
165 memcpy(val, pointer, length);
169 static int property_entry_read_string_array(const struct property_entry *props,
170 const char *propname,
171 const char **strings, size_t nval)
177 /* Find out the array length. */
178 array_len = property_entry_count_elems_of_size(props, propname,
179 sizeof(const char *));
183 /* Return how many there are if strings is NULL. */
187 array_len = min_t(size_t, nval, array_len);
188 length = array_len * sizeof(*strings);
190 pointer = property_entry_find(props, propname, length);
192 return PTR_ERR(pointer);
194 memcpy(strings, pointer, length);
199 static void property_entry_free_data(const struct property_entry *p)
201 const char * const *src_str;
204 if (p->type == DEV_PROP_STRING) {
205 src_str = property_get_pointer(p);
206 nval = p->length / sizeof(*src_str);
207 for (i = 0; i < nval; i++)
217 static bool property_copy_string_array(const char **dst_ptr,
218 const char * const *src_ptr,
223 for (i = 0; i < nval; i++) {
224 dst_ptr[i] = kstrdup(src_ptr[i], GFP_KERNEL);
225 if (!dst_ptr[i] && src_ptr[i]) {
235 static int property_entry_copy_data(struct property_entry *dst,
236 const struct property_entry *src)
238 const void *pointer = property_get_pointer(src);
243 * Properties with no data should not be marked as stored
246 if (!src->is_inline && !src->length)
250 * Reference properties are never stored inline as
253 if (src->type == DEV_PROP_REF && src->is_inline)
256 if (src->length <= sizeof(dst->value)) {
257 dst_ptr = &dst->value;
258 dst->is_inline = true;
260 dst_ptr = kmalloc(src->length, GFP_KERNEL);
263 dst->pointer = dst_ptr;
266 if (src->type == DEV_PROP_STRING) {
267 nval = src->length / sizeof(const char *);
268 if (!property_copy_string_array(dst_ptr, pointer, nval)) {
274 memcpy(dst_ptr, pointer, src->length);
277 dst->length = src->length;
278 dst->type = src->type;
279 dst->name = kstrdup(src->name, GFP_KERNEL);
281 property_entry_free_data(dst);
289 * property_entries_dup - duplicate array of properties
290 * @properties: array of properties to copy
292 * This function creates a deep copy of the given NULL-terminated array
293 * of property entries.
295 struct property_entry *
296 property_entries_dup(const struct property_entry *properties)
298 struct property_entry *p;
305 while (properties[n].name)
308 p = kcalloc(n + 1, sizeof(*p), GFP_KERNEL);
310 return ERR_PTR(-ENOMEM);
312 for (i = 0; i < n; i++) {
313 ret = property_entry_copy_data(&p[i], &properties[i]);
316 property_entry_free_data(&p[i]);
324 EXPORT_SYMBOL_GPL(property_entries_dup);
327 * property_entries_free - free previously allocated array of properties
328 * @properties: array of properties to destroy
330 * This function frees given NULL-terminated array of property entries,
331 * along with their data.
333 void property_entries_free(const struct property_entry *properties)
335 const struct property_entry *p;
340 for (p = properties; p->name; p++)
341 property_entry_free_data(p);
345 EXPORT_SYMBOL_GPL(property_entries_free);
347 /* -------------------------------------------------------------------------- */
348 /* fwnode operations */
350 static struct fwnode_handle *software_node_get(struct fwnode_handle *fwnode)
352 struct swnode *swnode = to_swnode(fwnode);
354 kobject_get(&swnode->kobj);
356 return &swnode->fwnode;
359 static void software_node_put(struct fwnode_handle *fwnode)
361 struct swnode *swnode = to_swnode(fwnode);
363 kobject_put(&swnode->kobj);
366 static bool software_node_property_present(const struct fwnode_handle *fwnode,
367 const char *propname)
369 struct swnode *swnode = to_swnode(fwnode);
371 return !!property_entry_get(swnode->node->properties, propname);
374 static int software_node_read_int_array(const struct fwnode_handle *fwnode,
375 const char *propname,
376 unsigned int elem_size, void *val,
379 struct swnode *swnode = to_swnode(fwnode);
381 return property_entry_read_int_array(swnode->node->properties, propname,
382 elem_size, val, nval);
385 static int software_node_read_string_array(const struct fwnode_handle *fwnode,
386 const char *propname,
387 const char **val, size_t nval)
389 struct swnode *swnode = to_swnode(fwnode);
391 return property_entry_read_string_array(swnode->node->properties,
392 propname, val, nval);
396 software_node_get_name(const struct fwnode_handle *fwnode)
398 const struct swnode *swnode = to_swnode(fwnode);
403 return kobject_name(&swnode->kobj);
407 software_node_get_name_prefix(const struct fwnode_handle *fwnode)
409 struct fwnode_handle *parent;
412 parent = fwnode_get_parent(fwnode);
416 /* Figure out the prefix from the parents. */
417 while (is_software_node(parent))
418 parent = fwnode_get_next_parent(parent);
420 prefix = fwnode_get_name_prefix(parent);
421 fwnode_handle_put(parent);
423 /* Guess something if prefix was NULL. */
424 return prefix ?: "/";
427 static struct fwnode_handle *
428 software_node_get_parent(const struct fwnode_handle *fwnode)
430 struct swnode *swnode = to_swnode(fwnode);
432 if (!swnode || !swnode->parent)
435 return fwnode_handle_get(&swnode->parent->fwnode);
438 static struct fwnode_handle *
439 software_node_get_next_child(const struct fwnode_handle *fwnode,
440 struct fwnode_handle *child)
442 struct swnode *p = to_swnode(fwnode);
443 struct swnode *c = to_swnode(child);
445 if (!p || list_empty(&p->children) ||
446 (c && list_is_last(&c->entry, &p->children))) {
447 fwnode_handle_put(child);
452 c = list_next_entry(c, entry);
454 c = list_first_entry(&p->children, struct swnode, entry);
456 fwnode_handle_put(child);
457 return fwnode_handle_get(&c->fwnode);
460 static struct fwnode_handle *
461 software_node_get_named_child_node(const struct fwnode_handle *fwnode,
462 const char *childname)
464 struct swnode *swnode = to_swnode(fwnode);
465 struct swnode *child;
467 if (!swnode || list_empty(&swnode->children))
470 list_for_each_entry(child, &swnode->children, entry) {
471 if (!strcmp(childname, kobject_name(&child->kobj))) {
472 kobject_get(&child->kobj);
473 return &child->fwnode;
480 software_node_get_reference_args(const struct fwnode_handle *fwnode,
481 const char *propname, const char *nargs_prop,
482 unsigned int nargs, unsigned int index,
483 struct fwnode_reference_args *args)
485 struct swnode *swnode = to_swnode(fwnode);
486 const struct software_node_ref_args *ref_array;
487 const struct software_node_ref_args *ref;
488 const struct property_entry *prop;
489 struct fwnode_handle *refnode;
497 prop = property_entry_get(swnode->node->properties, propname);
501 if (prop->type != DEV_PROP_REF)
505 * We expect that references are never stored inline, even
506 * single ones, as they are too big.
511 if (index * sizeof(*ref) >= prop->length)
514 ref_array = prop->pointer;
515 ref = &ref_array[index];
517 refnode = software_node_fwnode(ref->node);
522 error = property_entry_read_int_array(ref->node->properties,
523 nargs_prop, sizeof(u32),
528 nargs = nargs_prop_val;
531 if (nargs > NR_FWNODE_REFERENCE_ARGS)
534 args->fwnode = software_node_get(refnode);
537 for (i = 0; i < nargs; i++)
538 args->args[i] = ref->args[i];
543 static const struct fwnode_operations software_node_ops = {
544 .get = software_node_get,
545 .put = software_node_put,
546 .property_present = software_node_property_present,
547 .property_read_int_array = software_node_read_int_array,
548 .property_read_string_array = software_node_read_string_array,
549 .get_name = software_node_get_name,
550 .get_name_prefix = software_node_get_name_prefix,
551 .get_parent = software_node_get_parent,
552 .get_next_child_node = software_node_get_next_child,
553 .get_named_child_node = software_node_get_named_child_node,
554 .get_reference_args = software_node_get_reference_args
557 /* -------------------------------------------------------------------------- */
560 * software_node_find_by_name - Find software node by name
561 * @parent: Parent of the software node
562 * @name: Name of the software node
564 * The function will find a node that is child of @parent and that is named
565 * @name. If no node is found, the function returns NULL.
567 * NOTE: you will need to drop the reference with fwnode_handle_put() after use.
569 const struct software_node *
570 software_node_find_by_name(const struct software_node *parent, const char *name)
572 struct swnode *swnode = NULL;
578 spin_lock(&swnode_kset->list_lock);
580 list_for_each_entry(k, &swnode_kset->list, entry) {
581 swnode = kobj_to_swnode(k);
582 if (parent == swnode->node->parent && swnode->node->name &&
583 !strcmp(name, swnode->node->name)) {
584 kobject_get(&swnode->kobj);
590 spin_unlock(&swnode_kset->list_lock);
592 return swnode ? swnode->node : NULL;
594 EXPORT_SYMBOL_GPL(software_node_find_by_name);
597 software_node_register_properties(struct software_node *node,
598 const struct property_entry *properties)
600 struct property_entry *props;
602 props = property_entries_dup(properties);
604 return PTR_ERR(props);
606 node->properties = props;
611 static void software_node_release(struct kobject *kobj)
613 struct swnode *swnode = kobj_to_swnode(kobj);
615 if (swnode->parent) {
616 ida_simple_remove(&swnode->parent->child_ids, swnode->id);
617 list_del(&swnode->entry);
619 ida_simple_remove(&swnode_root_ids, swnode->id);
622 if (swnode->allocated) {
623 property_entries_free(swnode->node->properties);
626 ida_destroy(&swnode->child_ids);
630 static struct kobj_type software_node_type = {
631 .release = software_node_release,
632 .sysfs_ops = &kobj_sysfs_ops,
635 static struct fwnode_handle *
636 swnode_register(const struct software_node *node, struct swnode *parent,
637 unsigned int allocated)
639 struct swnode *swnode;
642 swnode = kzalloc(sizeof(*swnode), GFP_KERNEL);
648 ret = ida_simple_get(parent ? &parent->child_ids : &swnode_root_ids,
657 swnode->parent = parent;
658 swnode->allocated = allocated;
659 swnode->kobj.kset = swnode_kset;
660 swnode->fwnode.ops = &software_node_ops;
662 ida_init(&swnode->child_ids);
663 INIT_LIST_HEAD(&swnode->entry);
664 INIT_LIST_HEAD(&swnode->children);
667 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
668 parent ? &parent->kobj : NULL,
671 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
672 parent ? &parent->kobj : NULL,
673 "node%d", swnode->id);
675 kobject_put(&swnode->kobj);
680 list_add_tail(&swnode->entry, &parent->children);
682 kobject_uevent(&swnode->kobj, KOBJ_ADD);
683 return &swnode->fwnode;
687 property_entries_free(node->properties);
692 * software_node_register_nodes - Register an array of software nodes
693 * @nodes: Zero terminated array of software nodes to be registered
695 * Register multiple software nodes at once.
697 int software_node_register_nodes(const struct software_node *nodes)
702 for (i = 0; nodes[i].name; i++) {
703 ret = software_node_register(&nodes[i]);
705 software_node_unregister_nodes(nodes);
712 EXPORT_SYMBOL_GPL(software_node_register_nodes);
715 * software_node_unregister_nodes - Unregister an array of software nodes
716 * @nodes: Zero terminated array of software nodes to be unregistered
718 * Unregister multiple software nodes at once.
720 * NOTE: Be careful using this call if the nodes had parent pointers set up in
721 * them before registering. If so, it is wiser to remove the nodes
722 * individually, in the correct order (child before parent) instead of relying
723 * on the sequential order of the list of nodes in the array.
725 void software_node_unregister_nodes(const struct software_node *nodes)
729 for (i = 0; nodes[i].name; i++)
730 software_node_unregister(&nodes[i]);
732 EXPORT_SYMBOL_GPL(software_node_unregister_nodes);
735 * software_node_register_node_group - Register a group of software nodes
736 * @node_group: NULL terminated array of software node pointers to be registered
738 * Register multiple software nodes at once.
740 int software_node_register_node_group(const struct software_node **node_group)
748 for (i = 0; node_group[i]; i++) {
749 ret = software_node_register(node_group[i]);
751 software_node_unregister_node_group(node_group);
758 EXPORT_SYMBOL_GPL(software_node_register_node_group);
761 * software_node_unregister_node_group - Unregister a group of software nodes
762 * @node_group: NULL terminated array of software node pointers to be unregistered
764 * Unregister multiple software nodes at once.
766 void software_node_unregister_node_group(const struct software_node **node_group)
773 for (i = 0; node_group[i]; i++)
774 software_node_unregister(node_group[i]);
776 EXPORT_SYMBOL_GPL(software_node_unregister_node_group);
779 * software_node_register - Register static software node
780 * @node: The software node to be registered
782 int software_node_register(const struct software_node *node)
784 struct swnode *parent = software_node_to_swnode(node->parent);
786 if (software_node_to_swnode(node))
789 if (node->parent && !parent)
792 return PTR_ERR_OR_ZERO(swnode_register(node, parent, 0));
794 EXPORT_SYMBOL_GPL(software_node_register);
797 * software_node_unregister - Unregister static software node
798 * @node: The software node to be unregistered
800 void software_node_unregister(const struct software_node *node)
802 struct swnode *swnode;
804 swnode = software_node_to_swnode(node);
806 fwnode_remove_software_node(&swnode->fwnode);
808 EXPORT_SYMBOL_GPL(software_node_unregister);
810 struct fwnode_handle *
811 fwnode_create_software_node(const struct property_entry *properties,
812 const struct fwnode_handle *parent)
814 struct software_node *node;
815 struct swnode *p = NULL;
820 return ERR_CAST(parent);
821 if (!is_software_node(parent))
822 return ERR_PTR(-EINVAL);
823 p = to_swnode(parent);
826 node = kzalloc(sizeof(*node), GFP_KERNEL);
828 return ERR_PTR(-ENOMEM);
830 ret = software_node_register_properties(node, properties);
836 node->parent = p ? p->node : NULL;
838 return swnode_register(node, p, 1);
840 EXPORT_SYMBOL_GPL(fwnode_create_software_node);
842 void fwnode_remove_software_node(struct fwnode_handle *fwnode)
844 struct swnode *swnode = to_swnode(fwnode);
849 kobject_put(&swnode->kobj);
851 EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
853 int software_node_notify(struct device *dev, unsigned long action)
855 struct fwnode_handle *fwnode = dev_fwnode(dev);
856 struct swnode *swnode;
862 if (!is_software_node(fwnode))
863 fwnode = fwnode->secondary;
864 if (!is_software_node(fwnode))
867 swnode = to_swnode(fwnode);
871 ret = sysfs_create_link(&dev->kobj, &swnode->kobj,
876 ret = sysfs_create_link(&swnode->kobj, &dev->kobj,
879 sysfs_remove_link(&dev->kobj, "software_node");
882 kobject_get(&swnode->kobj);
885 sysfs_remove_link(&swnode->kobj, dev_name(dev));
886 sysfs_remove_link(&dev->kobj, "software_node");
887 kobject_put(&swnode->kobj);
896 static int __init software_node_init(void)
898 swnode_kset = kset_create_and_add("software_nodes", NULL, kernel_kobj);
903 postcore_initcall(software_node_init);
905 static void __exit software_node_exit(void)
907 ida_destroy(&swnode_root_ids);
908 kset_unregister(swnode_kset);
910 __exitcall(software_node_exit);