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device property: Add fwnode_get_name for returning the name of a node
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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
14 struct 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
29 static DEFINE_IDA(swnode_root_ids);
30 static struct kset *swnode_kset;
31
32 #define kobj_to_swnode(_kobj_) container_of(_kobj_, struct swnode, kobj)
33
34 static const struct fwnode_operations software_node_ops;
35
36 bool is_software_node(const struct fwnode_handle *fwnode)
37 {
38 return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &software_node_ops;
39 }
40 EXPORT_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
51 static struct swnode *
52 software_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
74 const struct software_node *to_software_node(const struct fwnode_handle *fwnode)
75 {
76 const struct swnode *swnode = to_swnode(fwnode);
77
78 return swnode ? swnode->node : NULL;
79 }
80 EXPORT_SYMBOL_GPL(to_software_node);
81
82 struct 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 }
88 EXPORT_SYMBOL_GPL(software_node_fwnode);
89
90 /* -------------------------------------------------------------------------- */
91 /* property_entry processing */
92
93 static const struct property_entry *
94 property_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
106 static void
107 property_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
145 static 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
173 static 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
190 static 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
205 static 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
220 static 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
235 static 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
250 static int
251 property_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
263 static 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
285 static 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
322 static 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
340 static 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
365 static 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
406 out_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 */
418 struct property_entry *
419 property_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 }
447 EXPORT_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 */
456 void 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 }
468 EXPORT_SYMBOL_GPL(property_entries_free);
469
470 /* -------------------------------------------------------------------------- */
471 /* fwnode operations */
472
473 static 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
482 static void software_node_put(struct fwnode_handle *fwnode)
483 {
484 struct swnode *swnode = to_swnode(fwnode);
485
486 kobject_put(&swnode->kobj);
487 }
488
489 static 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
497 static 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
508 static 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
518 static const char *
519 software_node_get_name(const struct fwnode_handle *fwnode)
520 {
521 const struct swnode *swnode = to_swnode(fwnode);
522
523 if (!swnode)
524 return "(null)";
525
526 return kobject_name(&swnode->kobj);
527 }
528
529 static struct fwnode_handle *
530 software_node_get_parent(const struct fwnode_handle *fwnode)
531 {
532 struct swnode *swnode = to_swnode(fwnode);
533
534 if (!swnode || !swnode->parent)
535 return NULL;
536
537 return fwnode_handle_get(&swnode->parent->fwnode);
538 }
539
540 static struct fwnode_handle *
541 software_node_get_next_child(const struct fwnode_handle *fwnode,
542 struct fwnode_handle *child)
543 {
544 struct swnode *p = to_swnode(fwnode);
545 struct swnode *c = to_swnode(child);
546
547 if (!p || list_empty(&p->children) ||
548 (c && list_is_last(&c->entry, &p->children)))
549 return NULL;
550
551 if (c)
552 c = list_next_entry(c, entry);
553 else
554 c = list_first_entry(&p->children, struct swnode, entry);
555 return &c->fwnode;
556 }
557
558 static struct fwnode_handle *
559 software_node_get_named_child_node(const struct fwnode_handle *fwnode,
560 const char *childname)
561 {
562 struct swnode *swnode = to_swnode(fwnode);
563 struct swnode *child;
564
565 if (!swnode || list_empty(&swnode->children))
566 return NULL;
567
568 list_for_each_entry(child, &swnode->children, entry) {
569 if (!strcmp(childname, kobject_name(&child->kobj))) {
570 kobject_get(&child->kobj);
571 return &child->fwnode;
572 }
573 }
574 return NULL;
575 }
576
577 static int
578 software_node_get_reference_args(const struct fwnode_handle *fwnode,
579 const char *propname, const char *nargs_prop,
580 unsigned int nargs, unsigned int index,
581 struct fwnode_reference_args *args)
582 {
583 struct swnode *swnode = to_swnode(fwnode);
584 const struct software_node_reference *ref;
585 const struct property_entry *prop;
586 struct fwnode_handle *refnode;
587 int i;
588
589 if (!swnode || !swnode->node->references)
590 return -ENOENT;
591
592 for (ref = swnode->node->references; ref->name; ref++)
593 if (!strcmp(ref->name, propname))
594 break;
595
596 if (!ref->name || index > (ref->nrefs - 1))
597 return -ENOENT;
598
599 refnode = software_node_fwnode(ref->refs[index].node);
600 if (!refnode)
601 return -ENOENT;
602
603 if (nargs_prop) {
604 prop = property_entry_get(swnode->node->properties, nargs_prop);
605 if (!prop)
606 return -EINVAL;
607
608 nargs = prop->value.u32_data;
609 }
610
611 if (nargs > NR_FWNODE_REFERENCE_ARGS)
612 return -EINVAL;
613
614 args->fwnode = software_node_get(refnode);
615 args->nargs = nargs;
616
617 for (i = 0; i < nargs; i++)
618 args->args[i] = ref->refs[index].args[i];
619
620 return 0;
621 }
622
623 static const struct fwnode_operations software_node_ops = {
624 .get = software_node_get,
625 .put = software_node_put,
626 .property_present = software_node_property_present,
627 .property_read_int_array = software_node_read_int_array,
628 .property_read_string_array = software_node_read_string_array,
629 .get_name = software_node_get_name,
630 .get_parent = software_node_get_parent,
631 .get_next_child_node = software_node_get_next_child,
632 .get_named_child_node = software_node_get_named_child_node,
633 .get_reference_args = software_node_get_reference_args
634 };
635
636 /* -------------------------------------------------------------------------- */
637
638 /**
639 * software_node_find_by_name - Find software node by name
640 * @parent: Parent of the software node
641 * @name: Name of the software node
642 *
643 * The function will find a node that is child of @parent and that is named
644 * @name. If no node is found, the function returns NULL.
645 *
646 * NOTE: you will need to drop the reference with fwnode_handle_put() after use.
647 */
648 const struct software_node *
649 software_node_find_by_name(const struct software_node *parent, const char *name)
650 {
651 struct swnode *swnode = NULL;
652 struct kobject *k;
653
654 if (!name)
655 return NULL;
656
657 spin_lock(&swnode_kset->list_lock);
658
659 list_for_each_entry(k, &swnode_kset->list, entry) {
660 swnode = kobj_to_swnode(k);
661 if (parent == swnode->node->parent && swnode->node->name &&
662 !strcmp(name, swnode->node->name)) {
663 kobject_get(&swnode->kobj);
664 break;
665 }
666 swnode = NULL;
667 }
668
669 spin_unlock(&swnode_kset->list_lock);
670
671 return swnode ? swnode->node : NULL;
672 }
673 EXPORT_SYMBOL_GPL(software_node_find_by_name);
674
675 static int
676 software_node_register_properties(struct software_node *node,
677 const struct property_entry *properties)
678 {
679 struct property_entry *props;
680
681 props = property_entries_dup(properties);
682 if (IS_ERR(props))
683 return PTR_ERR(props);
684
685 node->properties = props;
686
687 return 0;
688 }
689
690 static void software_node_release(struct kobject *kobj)
691 {
692 struct swnode *swnode = kobj_to_swnode(kobj);
693
694 if (swnode->allocated) {
695 property_entries_free(swnode->node->properties);
696 kfree(swnode->node);
697 }
698 ida_destroy(&swnode->child_ids);
699 kfree(swnode);
700 }
701
702 static struct kobj_type software_node_type = {
703 .release = software_node_release,
704 .sysfs_ops = &kobj_sysfs_ops,
705 };
706
707 static struct fwnode_handle *
708 swnode_register(const struct software_node *node, struct swnode *parent,
709 unsigned int allocated)
710 {
711 struct swnode *swnode;
712 int ret;
713
714 swnode = kzalloc(sizeof(*swnode), GFP_KERNEL);
715 if (!swnode) {
716 ret = -ENOMEM;
717 goto out_err;
718 }
719
720 ret = ida_simple_get(parent ? &parent->child_ids : &swnode_root_ids,
721 0, 0, GFP_KERNEL);
722 if (ret < 0) {
723 kfree(swnode);
724 goto out_err;
725 }
726
727 swnode->id = ret;
728 swnode->node = node;
729 swnode->parent = parent;
730 swnode->allocated = allocated;
731 swnode->kobj.kset = swnode_kset;
732 swnode->fwnode.ops = &software_node_ops;
733
734 ida_init(&swnode->child_ids);
735 INIT_LIST_HEAD(&swnode->entry);
736 INIT_LIST_HEAD(&swnode->children);
737
738 if (node->name)
739 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
740 parent ? &parent->kobj : NULL,
741 "%s", node->name);
742 else
743 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
744 parent ? &parent->kobj : NULL,
745 "node%d", swnode->id);
746 if (ret) {
747 kobject_put(&swnode->kobj);
748 return ERR_PTR(ret);
749 }
750
751 if (parent)
752 list_add_tail(&swnode->entry, &parent->children);
753
754 kobject_uevent(&swnode->kobj, KOBJ_ADD);
755 return &swnode->fwnode;
756
757 out_err:
758 if (allocated)
759 property_entries_free(node->properties);
760 return ERR_PTR(ret);
761 }
762
763 /**
764 * software_node_register_nodes - Register an array of software nodes
765 * @nodes: Zero terminated array of software nodes to be registered
766 *
767 * Register multiple software nodes at once.
768 */
769 int software_node_register_nodes(const struct software_node *nodes)
770 {
771 int ret;
772 int i;
773
774 for (i = 0; nodes[i].name; i++) {
775 ret = software_node_register(&nodes[i]);
776 if (ret) {
777 software_node_unregister_nodes(nodes);
778 return ret;
779 }
780 }
781
782 return 0;
783 }
784 EXPORT_SYMBOL_GPL(software_node_register_nodes);
785
786 /**
787 * software_node_unregister_nodes - Unregister an array of software nodes
788 * @nodes: Zero terminated array of software nodes to be unregistered
789 *
790 * Unregister multiple software nodes at once.
791 */
792 void software_node_unregister_nodes(const struct software_node *nodes)
793 {
794 struct swnode *swnode;
795 int i;
796
797 for (i = 0; nodes[i].name; i++) {
798 swnode = software_node_to_swnode(&nodes[i]);
799 if (swnode)
800 fwnode_remove_software_node(&swnode->fwnode);
801 }
802 }
803 EXPORT_SYMBOL_GPL(software_node_unregister_nodes);
804
805 /**
806 * software_node_register - Register static software node
807 * @node: The software node to be registered
808 */
809 int software_node_register(const struct software_node *node)
810 {
811 struct swnode *parent = software_node_to_swnode(node->parent);
812
813 if (software_node_to_swnode(node))
814 return -EEXIST;
815
816 return PTR_ERR_OR_ZERO(swnode_register(node, parent, 0));
817 }
818 EXPORT_SYMBOL_GPL(software_node_register);
819
820 struct fwnode_handle *
821 fwnode_create_software_node(const struct property_entry *properties,
822 const struct fwnode_handle *parent)
823 {
824 struct software_node *node;
825 struct swnode *p = NULL;
826 int ret;
827
828 if (parent) {
829 if (IS_ERR(parent))
830 return ERR_CAST(parent);
831 if (!is_software_node(parent))
832 return ERR_PTR(-EINVAL);
833 p = to_swnode(parent);
834 }
835
836 node = kzalloc(sizeof(*node), GFP_KERNEL);
837 if (!node)
838 return ERR_PTR(-ENOMEM);
839
840 ret = software_node_register_properties(node, properties);
841 if (ret) {
842 kfree(node);
843 return ERR_PTR(ret);
844 }
845
846 node->parent = p ? p->node : NULL;
847
848 return swnode_register(node, p, 1);
849 }
850 EXPORT_SYMBOL_GPL(fwnode_create_software_node);
851
852 void fwnode_remove_software_node(struct fwnode_handle *fwnode)
853 {
854 struct swnode *swnode = to_swnode(fwnode);
855
856 if (!swnode)
857 return;
858
859 if (swnode->parent) {
860 ida_simple_remove(&swnode->parent->child_ids, swnode->id);
861 list_del(&swnode->entry);
862 } else {
863 ida_simple_remove(&swnode_root_ids, swnode->id);
864 }
865
866 kobject_put(&swnode->kobj);
867 }
868 EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
869
870 int software_node_notify(struct device *dev, unsigned long action)
871 {
872 struct fwnode_handle *fwnode = dev_fwnode(dev);
873 struct swnode *swnode;
874 int ret;
875
876 if (!fwnode)
877 return 0;
878
879 if (!is_software_node(fwnode))
880 fwnode = fwnode->secondary;
881 if (!is_software_node(fwnode))
882 return 0;
883
884 swnode = to_swnode(fwnode);
885
886 switch (action) {
887 case KOBJ_ADD:
888 ret = sysfs_create_link(&dev->kobj, &swnode->kobj,
889 "software_node");
890 if (ret)
891 break;
892
893 ret = sysfs_create_link(&swnode->kobj, &dev->kobj,
894 dev_name(dev));
895 if (ret) {
896 sysfs_remove_link(&dev->kobj, "software_node");
897 break;
898 }
899 kobject_get(&swnode->kobj);
900 break;
901 case KOBJ_REMOVE:
902 sysfs_remove_link(&swnode->kobj, dev_name(dev));
903 sysfs_remove_link(&dev->kobj, "software_node");
904 kobject_put(&swnode->kobj);
905 break;
906 default:
907 break;
908 }
909
910 return 0;
911 }
912
913 static int __init software_node_init(void)
914 {
915 swnode_kset = kset_create_and_add("software_nodes", NULL, kernel_kobj);
916 if (!swnode_kset)
917 return -ENOMEM;
918 return 0;
919 }
920 postcore_initcall(software_node_init);
921
922 static void __exit software_node_exit(void)
923 {
924 ida_destroy(&swnode_root_ids);
925 kset_unregister(swnode_kset);
926 }
927 __exitcall(software_node_exit);