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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Software nodes for the firmware node framework.
4 *
5 * Copyright (C) 2018, Intel Corporation
6 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
7 */
8
9#include <linux/device.h>
10#include <linux/kernel.h>
11#include <linux/property.h>
12#include <linux/slab.h>
13
14struct swnode {
15 int id;
16 struct kobject kobj;
17 struct fwnode_handle fwnode;
18 const struct software_node *node;
19
20 /* hierarchy */
21 struct ida child_ids;
22 struct list_head entry;
23 struct list_head children;
24 struct swnode *parent;
25
26 unsigned int allocated:1;
27};
28
29static DEFINE_IDA(swnode_root_ids);
30static struct kset *swnode_kset;
31
32#define kobj_to_swnode(_kobj_) container_of(_kobj_, struct swnode, kobj)
33
34static const struct fwnode_operations software_node_ops;
35
36bool is_software_node(const struct fwnode_handle *fwnode)
37{
38 return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &software_node_ops;
39}
40EXPORT_SYMBOL_GPL(is_software_node);
41
42#define to_swnode(__fwnode) \
43 ({ \
44 typeof(__fwnode) __to_swnode_fwnode = __fwnode; \
45 \
46 is_software_node(__to_swnode_fwnode) ? \
47 container_of(__to_swnode_fwnode, \
48 struct swnode, fwnode) : NULL; \
49 })
50
51static struct swnode *
52software_node_to_swnode(const struct software_node *node)
53{
54 struct swnode *swnode = NULL;
55 struct kobject *k;
56
57 if (!node)
58 return NULL;
59
60 spin_lock(&swnode_kset->list_lock);
61
62 list_for_each_entry(k, &swnode_kset->list, entry) {
63 swnode = kobj_to_swnode(k);
64 if (swnode->node == node)
65 break;
66 swnode = NULL;
67 }
68
69 spin_unlock(&swnode_kset->list_lock);
70
71 return swnode;
72}
73
74const struct software_node *to_software_node(struct fwnode_handle *fwnode)
75{
76 struct swnode *swnode = to_swnode(fwnode);
77
78 return swnode ? swnode->node : NULL;
79}
80EXPORT_SYMBOL_GPL(to_software_node);
81
82struct fwnode_handle *software_node_fwnode(const struct software_node *node)
83{
84 struct swnode *swnode = software_node_to_swnode(node);
85
86 return swnode ? &swnode->fwnode : NULL;
87}
88EXPORT_SYMBOL_GPL(software_node_fwnode);
89
90/* -------------------------------------------------------------------------- */
91/* property_entry processing */
92
93static const struct property_entry *
94property_entry_get(const struct property_entry *prop, const char *name)
95{
96 if (!prop)
97 return NULL;
98
99 for (; prop->name; prop++)
100 if (!strcmp(name, prop->name))
101 return prop;
102
103 return NULL;
104}
105
106static void
107property_set_pointer(struct property_entry *prop, const void *pointer)
108{
109 switch (prop->type) {
110 case DEV_PROP_U8:
111 if (prop->is_array)
112 prop->pointer.u8_data = pointer;
113 else
114 prop->value.u8_data = *((u8 *)pointer);
115 break;
116 case DEV_PROP_U16:
117 if (prop->is_array)
118 prop->pointer.u16_data = pointer;
119 else
120 prop->value.u16_data = *((u16 *)pointer);
121 break;
122 case DEV_PROP_U32:
123 if (prop->is_array)
124 prop->pointer.u32_data = pointer;
125 else
126 prop->value.u32_data = *((u32 *)pointer);
127 break;
128 case DEV_PROP_U64:
129 if (prop->is_array)
130 prop->pointer.u64_data = pointer;
131 else
132 prop->value.u64_data = *((u64 *)pointer);
133 break;
134 case DEV_PROP_STRING:
135 if (prop->is_array)
136 prop->pointer.str = pointer;
137 else
138 prop->value.str = pointer;
139 break;
140 default:
141 break;
142 }
143}
144
145static const void *property_get_pointer(const struct property_entry *prop)
146{
147 switch (prop->type) {
148 case DEV_PROP_U8:
149 if (prop->is_array)
150 return prop->pointer.u8_data;
151 return &prop->value.u8_data;
152 case DEV_PROP_U16:
153 if (prop->is_array)
154 return prop->pointer.u16_data;
155 return &prop->value.u16_data;
156 case DEV_PROP_U32:
157 if (prop->is_array)
158 return prop->pointer.u32_data;
159 return &prop->value.u32_data;
160 case DEV_PROP_U64:
161 if (prop->is_array)
162 return prop->pointer.u64_data;
163 return &prop->value.u64_data;
164 case DEV_PROP_STRING:
165 if (prop->is_array)
166 return prop->pointer.str;
167 return &prop->value.str;
168 default:
169 return NULL;
170 }
171}
172
173static const void *property_entry_find(const struct property_entry *props,
174 const char *propname, size_t length)
175{
176 const struct property_entry *prop;
177 const void *pointer;
178
179 prop = property_entry_get(props, propname);
180 if (!prop)
181 return ERR_PTR(-EINVAL);
182 pointer = property_get_pointer(prop);
183 if (!pointer)
184 return ERR_PTR(-ENODATA);
185 if (length > prop->length)
186 return ERR_PTR(-EOVERFLOW);
187 return pointer;
188}
189
190static int property_entry_read_u8_array(const struct property_entry *props,
191 const char *propname,
192 u8 *values, size_t nval)
193{
194 const void *pointer;
195 size_t length = nval * sizeof(*values);
196
197 pointer = property_entry_find(props, propname, length);
198 if (IS_ERR(pointer))
199 return PTR_ERR(pointer);
200
201 memcpy(values, pointer, length);
202 return 0;
203}
204
205static int property_entry_read_u16_array(const struct property_entry *props,
206 const char *propname,
207 u16 *values, size_t nval)
208{
209 const void *pointer;
210 size_t length = nval * sizeof(*values);
211
212 pointer = property_entry_find(props, propname, length);
213 if (IS_ERR(pointer))
214 return PTR_ERR(pointer);
215
216 memcpy(values, pointer, length);
217 return 0;
218}
219
220static int property_entry_read_u32_array(const struct property_entry *props,
221 const char *propname,
222 u32 *values, size_t nval)
223{
224 const void *pointer;
225 size_t length = nval * sizeof(*values);
226
227 pointer = property_entry_find(props, propname, length);
228 if (IS_ERR(pointer))
229 return PTR_ERR(pointer);
230
231 memcpy(values, pointer, length);
232 return 0;
233}
234
235static int property_entry_read_u64_array(const struct property_entry *props,
236 const char *propname,
237 u64 *values, size_t nval)
238{
239 const void *pointer;
240 size_t length = nval * sizeof(*values);
241
242 pointer = property_entry_find(props, propname, length);
243 if (IS_ERR(pointer))
244 return PTR_ERR(pointer);
245
246 memcpy(values, pointer, length);
247 return 0;
248}
249
250static int
251property_entry_count_elems_of_size(const struct property_entry *props,
252 const char *propname, size_t length)
253{
254 const struct property_entry *prop;
255
256 prop = property_entry_get(props, propname);
257 if (!prop)
258 return -EINVAL;
259
260 return prop->length / length;
261}
262
263static int property_entry_read_int_array(const struct property_entry *props,
264 const char *name,
265 unsigned int elem_size, void *val,
266 size_t nval)
267{
268 if (!val)
269 return property_entry_count_elems_of_size(props, name,
270 elem_size);
271 switch (elem_size) {
272 case sizeof(u8):
273 return property_entry_read_u8_array(props, name, val, nval);
274 case sizeof(u16):
275 return property_entry_read_u16_array(props, name, val, nval);
276 case sizeof(u32):
277 return property_entry_read_u32_array(props, name, val, nval);
278 case sizeof(u64):
279 return property_entry_read_u64_array(props, name, val, nval);
280 }
281
282 return -ENXIO;
283}
284
285static int property_entry_read_string_array(const struct property_entry *props,
286 const char *propname,
287 const char **strings, size_t nval)
288{
289 const struct property_entry *prop;
290 const void *pointer;
291 size_t array_len, length;
292
293 /* Find out the array length. */
294 prop = property_entry_get(props, propname);
295 if (!prop)
296 return -EINVAL;
297
298 if (prop->is_array)
299 /* Find the length of an array. */
300 array_len = property_entry_count_elems_of_size(props, propname,
301 sizeof(const char *));
302 else
303 /* The array length for a non-array string property is 1. */
304 array_len = 1;
305
306 /* Return how many there are if strings is NULL. */
307 if (!strings)
308 return array_len;
309
310 array_len = min(nval, array_len);
311 length = array_len * sizeof(*strings);
312
313 pointer = property_entry_find(props, propname, length);
314 if (IS_ERR(pointer))
315 return PTR_ERR(pointer);
316
317 memcpy(strings, pointer, length);
318
319 return array_len;
320}
321
322static void property_entry_free_data(const struct property_entry *p)
323{
324 const void *pointer = property_get_pointer(p);
325 size_t i, nval;
326
327 if (p->is_array) {
328 if (p->type == DEV_PROP_STRING && p->pointer.str) {
329 nval = p->length / sizeof(const char *);
330 for (i = 0; i < nval; i++)
331 kfree(p->pointer.str[i]);
332 }
333 kfree(pointer);
334 } else if (p->type == DEV_PROP_STRING) {
335 kfree(p->value.str);
336 }
337 kfree(p->name);
338}
339
340static int property_copy_string_array(struct property_entry *dst,
341 const struct property_entry *src)
342{
343 const char **d;
344 size_t nval = src->length / sizeof(*d);
345 int i;
346
347 d = kcalloc(nval, sizeof(*d), GFP_KERNEL);
348 if (!d)
349 return -ENOMEM;
350
351 for (i = 0; i < nval; i++) {
352 d[i] = kstrdup(src->pointer.str[i], GFP_KERNEL);
353 if (!d[i] && src->pointer.str[i]) {
354 while (--i >= 0)
355 kfree(d[i]);
356 kfree(d);
357 return -ENOMEM;
358 }
359 }
360
361 dst->pointer.str = d;
362 return 0;
363}
364
365static int property_entry_copy_data(struct property_entry *dst,
366 const struct property_entry *src)
367{
368 const void *pointer = property_get_pointer(src);
369 const void *new;
370 int error;
371
372 if (src->is_array) {
373 if (!src->length)
374 return -ENODATA;
375
376 if (src->type == DEV_PROP_STRING) {
377 error = property_copy_string_array(dst, src);
378 if (error)
379 return error;
380 new = dst->pointer.str;
381 } else {
382 new = kmemdup(pointer, src->length, GFP_KERNEL);
383 if (!new)
384 return -ENOMEM;
385 }
386 } else if (src->type == DEV_PROP_STRING) {
387 new = kstrdup(src->value.str, GFP_KERNEL);
388 if (!new && src->value.str)
389 return -ENOMEM;
390 } else {
391 new = pointer;
392 }
393
394 dst->length = src->length;
395 dst->is_array = src->is_array;
396 dst->type = src->type;
397
398 property_set_pointer(dst, new);
399
400 dst->name = kstrdup(src->name, GFP_KERNEL);
401 if (!dst->name)
402 goto out_free_data;
403
404 return 0;
405
406out_free_data:
407 property_entry_free_data(dst);
408 return -ENOMEM;
409}
410
411/**
412 * property_entries_dup - duplicate array of properties
413 * @properties: array of properties to copy
414 *
415 * This function creates a deep copy of the given NULL-terminated array
416 * of property entries.
417 */
418struct property_entry *
419property_entries_dup(const struct property_entry *properties)
420{
421 struct property_entry *p;
422 int i, n = 0;
423 int ret;
424
425 if (!properties)
426 return NULL;
427
428 while (properties[n].name)
429 n++;
430
431 p = kcalloc(n + 1, sizeof(*p), GFP_KERNEL);
432 if (!p)
433 return ERR_PTR(-ENOMEM);
434
435 for (i = 0; i < n; i++) {
436 ret = property_entry_copy_data(&p[i], &properties[i]);
437 if (ret) {
438 while (--i >= 0)
439 property_entry_free_data(&p[i]);
440 kfree(p);
441 return ERR_PTR(ret);
442 }
443 }
444
445 return p;
446}
447EXPORT_SYMBOL_GPL(property_entries_dup);
448
449/**
450 * property_entries_free - free previously allocated array of properties
451 * @properties: array of properties to destroy
452 *
453 * This function frees given NULL-terminated array of property entries,
454 * along with their data.
455 */
456void property_entries_free(const struct property_entry *properties)
457{
458 const struct property_entry *p;
459
460 if (!properties)
461 return;
462
463 for (p = properties; p->name; p++)
464 property_entry_free_data(p);
465
466 kfree(properties);
467}
468EXPORT_SYMBOL_GPL(property_entries_free);
469
470/* -------------------------------------------------------------------------- */
471/* fwnode operations */
472
473static struct fwnode_handle *software_node_get(struct fwnode_handle *fwnode)
474{
475 struct swnode *swnode = to_swnode(fwnode);
476
477 kobject_get(&swnode->kobj);
478
479 return &swnode->fwnode;
480}
481
482static void software_node_put(struct fwnode_handle *fwnode)
483{
484 struct swnode *swnode = to_swnode(fwnode);
485
486 kobject_put(&swnode->kobj);
487}
488
489static bool software_node_property_present(const struct fwnode_handle *fwnode,
490 const char *propname)
491{
492 struct swnode *swnode = to_swnode(fwnode);
493
494 return !!property_entry_get(swnode->node->properties, propname);
495}
496
497static int software_node_read_int_array(const struct fwnode_handle *fwnode,
498 const char *propname,
499 unsigned int elem_size, void *val,
500 size_t nval)
501{
502 struct swnode *swnode = to_swnode(fwnode);
503
504 return property_entry_read_int_array(swnode->node->properties, propname,
505 elem_size, val, nval);
506}
507
508static int software_node_read_string_array(const struct fwnode_handle *fwnode,
509 const char *propname,
510 const char **val, size_t nval)
511{
512 struct swnode *swnode = to_swnode(fwnode);
513
514 return property_entry_read_string_array(swnode->node->properties,
515 propname, val, nval);
516}
517
518static struct fwnode_handle *
519software_node_get_parent(const struct fwnode_handle *fwnode)
520{
521 struct swnode *swnode = to_swnode(fwnode);
522
523 return swnode ? (swnode->parent ? &swnode->parent->fwnode : NULL) : NULL;
524}
525
526static struct fwnode_handle *
527software_node_get_next_child(const struct fwnode_handle *fwnode,
528 struct fwnode_handle *child)
529{
530 struct swnode *p = to_swnode(fwnode);
531 struct swnode *c = to_swnode(child);
532
533 if (!p || list_empty(&p->children) ||
534 (c && list_is_last(&c->entry, &p->children)))
535 return NULL;
536
537 if (c)
538 c = list_next_entry(c, entry);
539 else
540 c = list_first_entry(&p->children, struct swnode, entry);
541 return &c->fwnode;
542}
543
544static struct fwnode_handle *
545software_node_get_named_child_node(const struct fwnode_handle *fwnode,
546 const char *childname)
547{
548 struct swnode *swnode = to_swnode(fwnode);
549 struct swnode *child;
550
551 if (!swnode || list_empty(&swnode->children))
552 return NULL;
553
554 list_for_each_entry(child, &swnode->children, entry) {
555 if (!strcmp(childname, kobject_name(&child->kobj))) {
556 kobject_get(&child->kobj);
557 return &child->fwnode;
558 }
559 }
560 return NULL;
561}
562
563static int
564software_node_get_reference_args(const struct fwnode_handle *fwnode,
565 const char *propname, const char *nargs_prop,
566 unsigned int nargs, unsigned int index,
567 struct fwnode_reference_args *args)
568{
569 struct swnode *swnode = to_swnode(fwnode);
570 const struct software_node_reference *ref;
571 const struct property_entry *prop;
572 struct fwnode_handle *refnode;
573 int i;
574
575 if (!swnode || !swnode->node->references)
576 return -ENOENT;
577
578 for (ref = swnode->node->references; ref->name; ref++)
579 if (!strcmp(ref->name, propname))
580 break;
581
582 if (!ref->name || index > (ref->nrefs - 1))
583 return -ENOENT;
584
585 refnode = software_node_fwnode(ref->refs[index].node);
586 if (!refnode)
587 return -ENOENT;
588
589 if (nargs_prop) {
590 prop = property_entry_get(swnode->node->properties, nargs_prop);
591 if (!prop)
592 return -EINVAL;
593
594 nargs = prop->value.u32_data;
595 }
596
597 if (nargs > NR_FWNODE_REFERENCE_ARGS)
598 return -EINVAL;
599
600 args->fwnode = software_node_get(refnode);
601 args->nargs = nargs;
602
603 for (i = 0; i < nargs; i++)
604 args->args[i] = ref->refs[index].args[i];
605
606 return 0;
607}
608
609static const struct fwnode_operations software_node_ops = {
610 .get = software_node_get,
611 .put = software_node_put,
612 .property_present = software_node_property_present,
613 .property_read_int_array = software_node_read_int_array,
614 .property_read_string_array = software_node_read_string_array,
615 .get_parent = software_node_get_parent,
616 .get_next_child_node = software_node_get_next_child,
617 .get_named_child_node = software_node_get_named_child_node,
618 .get_reference_args = software_node_get_reference_args
619};
620
621/* -------------------------------------------------------------------------- */
622
623/**
624 * software_node_find_by_name - Find software node by name
625 * @parent: Parent of the software node
626 * @name: Name of the software node
627 *
628 * The function will find a node that is child of @parent and that is named
629 * @name. If no node is found, the function returns NULL.
630 *
631 * NOTE: you will need to drop the reference with fwnode_handle_put() after use.
632 */
633const struct software_node *
634software_node_find_by_name(const struct software_node *parent, const char *name)
635{
636 struct swnode *swnode = NULL;
637 struct kobject *k;
638
639 if (!name)
640 return NULL;
641
642 spin_lock(&swnode_kset->list_lock);
643
644 list_for_each_entry(k, &swnode_kset->list, entry) {
645 swnode = kobj_to_swnode(k);
646 if (parent == swnode->node->parent && swnode->node->name &&
647 !strcmp(name, swnode->node->name)) {
648 kobject_get(&swnode->kobj);
649 break;
650 }
651 swnode = NULL;
652 }
653
654 spin_unlock(&swnode_kset->list_lock);
655
656 return swnode ? swnode->node : NULL;
657}
658EXPORT_SYMBOL_GPL(software_node_find_by_name);
659
660static int
661software_node_register_properties(struct software_node *node,
662 const struct property_entry *properties)
663{
664 struct property_entry *props;
665
666 props = property_entries_dup(properties);
667 if (IS_ERR(props))
668 return PTR_ERR(props);
669
670 node->properties = props;
671
672 return 0;
673}
674
675static void software_node_release(struct kobject *kobj)
676{
677 struct swnode *swnode = kobj_to_swnode(kobj);
678
679 if (swnode->allocated) {
680 property_entries_free(swnode->node->properties);
681 kfree(swnode->node);
682 }
683 ida_destroy(&swnode->child_ids);
684 kfree(swnode);
685}
686
687static struct kobj_type software_node_type = {
688 .release = software_node_release,
689 .sysfs_ops = &kobj_sysfs_ops,
690};
691
692static struct fwnode_handle *
693swnode_register(const struct software_node *node, struct swnode *parent,
694 unsigned int allocated)
695{
696 struct swnode *swnode;
697 int ret;
698
699 swnode = kzalloc(sizeof(*swnode), GFP_KERNEL);
700 if (!swnode) {
701 ret = -ENOMEM;
702 goto out_err;
703 }
704
705 ret = ida_simple_get(parent ? &parent->child_ids : &swnode_root_ids,
706 0, 0, GFP_KERNEL);
707 if (ret < 0) {
708 kfree(swnode);
709 goto out_err;
710 }
711
712 swnode->id = ret;
713 swnode->node = node;
714 swnode->parent = parent;
715 swnode->allocated = allocated;
716 swnode->kobj.kset = swnode_kset;
717 swnode->fwnode.ops = &software_node_ops;
718
719 ida_init(&swnode->child_ids);
720 INIT_LIST_HEAD(&swnode->entry);
721 INIT_LIST_HEAD(&swnode->children);
722
723 if (node->name)
724 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
725 parent ? &parent->kobj : NULL,
726 "%s", node->name);
727 else
728 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
729 parent ? &parent->kobj : NULL,
730 "node%d", swnode->id);
731 if (ret) {
732 kobject_put(&swnode->kobj);
733 return ERR_PTR(ret);
734 }
735
736 if (parent)
737 list_add_tail(&swnode->entry, &parent->children);
738
739 kobject_uevent(&swnode->kobj, KOBJ_ADD);
740 return &swnode->fwnode;
741
742out_err:
743 if (allocated)
744 property_entries_free(node->properties);
745 return ERR_PTR(ret);
746}
747
748/**
749 * software_node_register_nodes - Register an array of software nodes
750 * @nodes: Zero terminated array of software nodes to be registered
751 *
752 * Register multiple software nodes at once.
753 */
754int software_node_register_nodes(const struct software_node *nodes)
755{
756 int ret;
757 int i;
758
759 for (i = 0; nodes[i].name; i++) {
760 ret = software_node_register(&nodes[i]);
761 if (ret) {
762 software_node_unregister_nodes(nodes);
763 return ret;
764 }
765 }
766
767 return 0;
768}
769EXPORT_SYMBOL_GPL(software_node_register_nodes);
770
771/**
772 * software_node_unregister_nodes - Unregister an array of software nodes
773 * @nodes: Zero terminated array of software nodes to be unregistered
774 *
775 * Unregister multiple software nodes at once.
776 */
777void software_node_unregister_nodes(const struct software_node *nodes)
778{
779 struct swnode *swnode;
780 int i;
781
782 for (i = 0; nodes[i].name; i++) {
783 swnode = software_node_to_swnode(&nodes[i]);
784 if (swnode)
785 fwnode_remove_software_node(&swnode->fwnode);
786 }
787}
788EXPORT_SYMBOL_GPL(software_node_unregister_nodes);
789
790/**
791 * software_node_register - Register static software node
792 * @node: The software node to be registered
793 */
794int software_node_register(const struct software_node *node)
795{
796 struct swnode *parent = software_node_to_swnode(node->parent);
797
798 if (software_node_to_swnode(node))
799 return -EEXIST;
800
801 return PTR_ERR_OR_ZERO(swnode_register(node, parent, 0));
802}
803EXPORT_SYMBOL_GPL(software_node_register);
804
805struct fwnode_handle *
806fwnode_create_software_node(const struct property_entry *properties,
807 const struct fwnode_handle *parent)
808{
809 struct software_node *node;
810 struct swnode *p = NULL;
811 int ret;
812
813 if (parent) {
814 if (IS_ERR(parent))
815 return ERR_CAST(parent);
816 if (!is_software_node(parent))
817 return ERR_PTR(-EINVAL);
818 p = to_swnode(parent);
819 }
820
821 node = kzalloc(sizeof(*node), GFP_KERNEL);
822 if (!node)
823 return ERR_PTR(-ENOMEM);
824
825 ret = software_node_register_properties(node, properties);
826 if (ret) {
827 kfree(node);
828 return ERR_PTR(ret);
829 }
830
831 node->parent = p ? p->node : NULL;
832
833 return swnode_register(node, p, 1);
834}
835EXPORT_SYMBOL_GPL(fwnode_create_software_node);
836
837void fwnode_remove_software_node(struct fwnode_handle *fwnode)
838{
839 struct swnode *swnode = to_swnode(fwnode);
840
841 if (!swnode)
842 return;
843
844 if (swnode->parent) {
845 ida_simple_remove(&swnode->parent->child_ids, swnode->id);
846 list_del(&swnode->entry);
847 } else {
848 ida_simple_remove(&swnode_root_ids, swnode->id);
849 }
850
851 kobject_put(&swnode->kobj);
852}
853EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
854
855int software_node_notify(struct device *dev, unsigned long action)
856{
857 struct fwnode_handle *fwnode = dev_fwnode(dev);
858 struct swnode *swnode;
859 int ret;
860
861 if (!fwnode)
862 return 0;
863
864 if (!is_software_node(fwnode))
865 fwnode = fwnode->secondary;
866 if (!is_software_node(fwnode))
867 return 0;
868
869 swnode = to_swnode(fwnode);
870
871 switch (action) {
872 case KOBJ_ADD:
873 ret = sysfs_create_link(&dev->kobj, &swnode->kobj,
874 "software_node");
875 if (ret)
876 break;
877
878 ret = sysfs_create_link(&swnode->kobj, &dev->kobj,
879 dev_name(dev));
880 if (ret) {
881 sysfs_remove_link(&dev->kobj, "software_node");
882 break;
883 }
884 kobject_get(&swnode->kobj);
885 break;
886 case KOBJ_REMOVE:
887 sysfs_remove_link(&swnode->kobj, dev_name(dev));
888 sysfs_remove_link(&dev->kobj, "software_node");
889 kobject_put(&swnode->kobj);
890 break;
891 default:
892 break;
893 }
894
895 return 0;
896}
897
898static int __init software_node_init(void)
899{
900 swnode_kset = kset_create_and_add("software_nodes", NULL, kernel_kobj);
901 if (!swnode_kset)
902 return -ENOMEM;
903 return 0;
904}
905postcore_initcall(software_node_init);
906
907static void __exit software_node_exit(void)
908{
909 ida_destroy(&swnode_root_ids);
910 kset_unregister(swnode_kset);
911}
912__exitcall(software_node_exit);