Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt
[linux-2.6-microblaze.git] / drivers / base / swnode.c
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(struct fwnode_handle *fwnode)
75 {
76         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 struct fwnode_handle *
519 software_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
526 static struct fwnode_handle *
527 software_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
544 static struct fwnode_handle *
545 software_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
563 static int
564 software_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
609 static 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  */
633 const struct software_node *
634 software_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 }
658 EXPORT_SYMBOL_GPL(software_node_find_by_name);
659
660 static int
661 software_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
675 static 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
687 static struct kobj_type software_node_type = {
688         .release = software_node_release,
689         .sysfs_ops = &kobj_sysfs_ops,
690 };
691
692 static struct fwnode_handle *
693 swnode_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
742 out_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  */
754 int 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 }
769 EXPORT_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  */
777 void 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 }
788 EXPORT_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  */
794 int 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 }
803 EXPORT_SYMBOL_GPL(software_node_register);
804
805 struct fwnode_handle *
806 fwnode_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 }
835 EXPORT_SYMBOL_GPL(fwnode_create_software_node);
836
837 void 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 }
853 EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
854
855 int 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
898 static 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 }
905 postcore_initcall(software_node_init);
906
907 static void __exit software_node_exit(void)
908 {
909         ida_destroy(&swnode_root_ids);
910         kset_unregister(swnode_kset);
911 }
912 __exitcall(software_node_exit);