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/container_of.h>
10#include <linux/device.h>
11#include <linux/err.h>
12#include <linux/export.h>
13#include <linux/idr.h>
14#include <linux/init.h>
15#include <linux/kobject.h>
16#include <linux/kstrtox.h>
17#include <linux/list.h>
18#include <linux/property.h>
19#include <linux/slab.h>
20#include <linux/spinlock.h>
21#include <linux/string.h>
22#include <linux/sysfs.h>
23#include <linux/types.h>
24
25#include "base.h"
26
27struct swnode {
28 struct kobject kobj;
29 struct fwnode_handle fwnode;
30 const struct software_node *node;
31 int id;
32
33 /* hierarchy */
34 struct ida child_ids;
35 struct list_head entry;
36 struct list_head children;
37 struct swnode *parent;
38
39 unsigned int allocated:1;
40 unsigned int managed:1;
41};
42
43static DEFINE_IDA(swnode_root_ids);
44static struct kset *swnode_kset;
45
46#define kobj_to_swnode(_kobj_) container_of(_kobj_, struct swnode, kobj)
47
48static const struct fwnode_operations software_node_ops;
49
50bool is_software_node(const struct fwnode_handle *fwnode)
51{
52 return !IS_ERR_OR_NULL(ptr: fwnode) && fwnode->ops == &software_node_ops;
53}
54EXPORT_SYMBOL_GPL(is_software_node);
55
56#define to_swnode(__fwnode) \
57 ({ \
58 typeof(__fwnode) __to_swnode_fwnode = __fwnode; \
59 \
60 is_software_node(__to_swnode_fwnode) ? \
61 container_of(__to_swnode_fwnode, \
62 struct swnode, fwnode) : NULL; \
63 })
64
65static inline struct swnode *dev_to_swnode(struct device *dev)
66{
67 struct fwnode_handle *fwnode = dev_fwnode(dev);
68
69 if (!fwnode)
70 return NULL;
71
72 if (!is_software_node(fwnode))
73 fwnode = fwnode->secondary;
74
75 return to_swnode(fwnode);
76}
77
78static struct swnode *
79software_node_to_swnode(const struct software_node *node)
80{
81 struct swnode *swnode = NULL;
82 struct kobject *k;
83
84 if (!node)
85 return NULL;
86
87 spin_lock(lock: &swnode_kset->list_lock);
88
89 list_for_each_entry(k, &swnode_kset->list, entry) {
90 swnode = kobj_to_swnode(k);
91 if (swnode->node == node)
92 break;
93 swnode = NULL;
94 }
95
96 spin_unlock(lock: &swnode_kset->list_lock);
97
98 return swnode;
99}
100
101const struct software_node *to_software_node(const struct fwnode_handle *fwnode)
102{
103 const struct swnode *swnode = to_swnode(fwnode);
104
105 return swnode ? swnode->node : NULL;
106}
107EXPORT_SYMBOL_GPL(to_software_node);
108
109struct fwnode_handle *software_node_fwnode(const struct software_node *node)
110{
111 struct swnode *swnode = software_node_to_swnode(node);
112
113 return swnode ? &swnode->fwnode : NULL;
114}
115EXPORT_SYMBOL_GPL(software_node_fwnode);
116
117/* -------------------------------------------------------------------------- */
118/* property_entry processing */
119
120static const struct property_entry *
121property_entry_get(const struct property_entry *prop, const char *name)
122{
123 if (!prop)
124 return NULL;
125
126 for (; prop->name; prop++)
127 if (!strcmp(name, prop->name))
128 return prop;
129
130 return NULL;
131}
132
133static const void *property_get_pointer(const struct property_entry *prop)
134{
135 if (!prop->length)
136 return NULL;
137
138 return prop->is_inline ? &prop->value : prop->pointer;
139}
140
141static const void *property_entry_find(const struct property_entry *props,
142 const char *propname, size_t length)
143{
144 const struct property_entry *prop;
145 const void *pointer;
146
147 prop = property_entry_get(prop: props, name: propname);
148 if (!prop)
149 return ERR_PTR(error: -EINVAL);
150 pointer = property_get_pointer(prop);
151 if (!pointer)
152 return ERR_PTR(error: -ENODATA);
153 if (length > prop->length)
154 return ERR_PTR(error: -EOVERFLOW);
155 return pointer;
156}
157
158static int
159property_entry_count_elems_of_size(const struct property_entry *props,
160 const char *propname, size_t length)
161{
162 const struct property_entry *prop;
163
164 prop = property_entry_get(prop: props, name: propname);
165 if (!prop)
166 return -EINVAL;
167
168 return prop->length / length;
169}
170
171static int property_entry_read_int_array(const struct property_entry *props,
172 const char *name,
173 unsigned int elem_size, void *val,
174 size_t nval)
175{
176 const void *pointer;
177 size_t length;
178
179 if (!val)
180 return property_entry_count_elems_of_size(props, propname: name,
181 length: elem_size);
182
183 if (!is_power_of_2(n: elem_size) || elem_size > sizeof(u64))
184 return -ENXIO;
185
186 length = nval * elem_size;
187
188 pointer = property_entry_find(props, propname: name, length);
189 if (IS_ERR(ptr: pointer))
190 return PTR_ERR(ptr: pointer);
191
192 memcpy(to: val, from: pointer, len: length);
193 return 0;
194}
195
196static int property_entry_read_string_array(const struct property_entry *props,
197 const char *propname,
198 const char **strings, size_t nval)
199{
200 const void *pointer;
201 size_t length;
202 int array_len;
203
204 /* Find out the array length. */
205 array_len = property_entry_count_elems_of_size(props, propname,
206 length: sizeof(const char *));
207 if (array_len < 0)
208 return array_len;
209
210 /* Return how many there are if strings is NULL. */
211 if (!strings)
212 return array_len;
213
214 array_len = min_t(size_t, nval, array_len);
215 length = array_len * sizeof(*strings);
216
217 pointer = property_entry_find(props, propname, length);
218 if (IS_ERR(ptr: pointer))
219 return PTR_ERR(ptr: pointer);
220
221 memcpy(to: strings, from: pointer, len: length);
222
223 return array_len;
224}
225
226static void property_entry_free_data(const struct property_entry *p)
227{
228 const char * const *src_str;
229 size_t i, nval;
230
231 if (p->type == DEV_PROP_STRING) {
232 src_str = property_get_pointer(prop: p);
233 nval = p->length / sizeof(*src_str);
234 for (i = 0; i < nval; i++)
235 kfree(objp: src_str[i]);
236 }
237
238 if (!p->is_inline)
239 kfree(objp: p->pointer);
240
241 kfree(objp: p->name);
242}
243
244static bool property_copy_string_array(const char **dst_ptr,
245 const char * const *src_ptr,
246 size_t nval)
247{
248 int i;
249
250 for (i = 0; i < nval; i++) {
251 dst_ptr[i] = kstrdup(s: src_ptr[i], GFP_KERNEL);
252 if (!dst_ptr[i] && src_ptr[i]) {
253 while (--i >= 0)
254 kfree(objp: dst_ptr[i]);
255 return false;
256 }
257 }
258
259 return true;
260}
261
262static int property_entry_copy_data(struct property_entry *dst,
263 const struct property_entry *src)
264{
265 const void *pointer = property_get_pointer(prop: src);
266 void *dst_ptr;
267 size_t nval;
268
269 /*
270 * Properties with no data should not be marked as stored
271 * out of line.
272 */
273 if (!src->is_inline && !src->length)
274 return -ENODATA;
275
276 /*
277 * Reference properties are never stored inline as
278 * they are too big.
279 */
280 if (src->type == DEV_PROP_REF && src->is_inline)
281 return -EINVAL;
282
283 if (src->length <= sizeof(dst->value)) {
284 dst_ptr = &dst->value;
285 dst->is_inline = true;
286 } else {
287 dst_ptr = kmalloc(src->length, GFP_KERNEL);
288 if (!dst_ptr)
289 return -ENOMEM;
290 dst->pointer = dst_ptr;
291 }
292
293 if (src->type == DEV_PROP_STRING) {
294 nval = src->length / sizeof(const char *);
295 if (!property_copy_string_array(dst_ptr, src_ptr: pointer, nval)) {
296 if (!dst->is_inline)
297 kfree(objp: dst->pointer);
298 return -ENOMEM;
299 }
300 } else {
301 memcpy(to: dst_ptr, from: pointer, len: src->length);
302 }
303
304 dst->length = src->length;
305 dst->type = src->type;
306 dst->name = kstrdup(s: src->name, GFP_KERNEL);
307 if (!dst->name) {
308 property_entry_free_data(p: dst);
309 return -ENOMEM;
310 }
311
312 return 0;
313}
314
315/**
316 * property_entries_dup - duplicate array of properties
317 * @properties: array of properties to copy
318 *
319 * This function creates a deep copy of the given NULL-terminated array
320 * of property entries.
321 */
322struct property_entry *
323property_entries_dup(const struct property_entry *properties)
324{
325 struct property_entry *p;
326 int i, n = 0;
327 int ret;
328
329 if (!properties)
330 return NULL;
331
332 while (properties[n].name)
333 n++;
334
335 p = kcalloc(n + 1, sizeof(*p), GFP_KERNEL);
336 if (!p)
337 return ERR_PTR(error: -ENOMEM);
338
339 for (i = 0; i < n; i++) {
340 ret = property_entry_copy_data(dst: &p[i], src: &properties[i]);
341 if (ret) {
342 while (--i >= 0)
343 property_entry_free_data(p: &p[i]);
344 kfree(objp: p);
345 return ERR_PTR(error: ret);
346 }
347 }
348
349 return p;
350}
351EXPORT_SYMBOL_GPL(property_entries_dup);
352
353/**
354 * property_entries_free - free previously allocated array of properties
355 * @properties: array of properties to destroy
356 *
357 * This function frees given NULL-terminated array of property entries,
358 * along with their data.
359 */
360void property_entries_free(const struct property_entry *properties)
361{
362 const struct property_entry *p;
363
364 if (!properties)
365 return;
366
367 for (p = properties; p->name; p++)
368 property_entry_free_data(p);
369
370 kfree(objp: properties);
371}
372EXPORT_SYMBOL_GPL(property_entries_free);
373
374/* -------------------------------------------------------------------------- */
375/* fwnode operations */
376
377static struct fwnode_handle *software_node_get(struct fwnode_handle *fwnode)
378{
379 struct swnode *swnode = to_swnode(fwnode);
380
381 kobject_get(kobj: &swnode->kobj);
382
383 return &swnode->fwnode;
384}
385
386static void software_node_put(struct fwnode_handle *fwnode)
387{
388 struct swnode *swnode = to_swnode(fwnode);
389
390 kobject_put(kobj: &swnode->kobj);
391}
392
393static bool software_node_property_present(const struct fwnode_handle *fwnode,
394 const char *propname)
395{
396 struct swnode *swnode = to_swnode(fwnode);
397
398 return !!property_entry_get(prop: swnode->node->properties, name: propname);
399}
400
401static int software_node_read_int_array(const struct fwnode_handle *fwnode,
402 const char *propname,
403 unsigned int elem_size, void *val,
404 size_t nval)
405{
406 struct swnode *swnode = to_swnode(fwnode);
407
408 return property_entry_read_int_array(props: swnode->node->properties, name: propname,
409 elem_size, val, nval);
410}
411
412static int software_node_read_string_array(const struct fwnode_handle *fwnode,
413 const char *propname,
414 const char **val, size_t nval)
415{
416 struct swnode *swnode = to_swnode(fwnode);
417
418 return property_entry_read_string_array(props: swnode->node->properties,
419 propname, strings: val, nval);
420}
421
422static const char *
423software_node_get_name(const struct fwnode_handle *fwnode)
424{
425 const struct swnode *swnode = to_swnode(fwnode);
426
427 return kobject_name(kobj: &swnode->kobj);
428}
429
430static const char *
431software_node_get_name_prefix(const struct fwnode_handle *fwnode)
432{
433 struct fwnode_handle *parent;
434 const char *prefix;
435
436 parent = fwnode_get_parent(fwnode);
437 if (!parent)
438 return "";
439
440 /* Figure out the prefix from the parents. */
441 while (is_software_node(parent))
442 parent = fwnode_get_next_parent(fwnode: parent);
443
444 prefix = fwnode_get_name_prefix(fwnode: parent);
445 fwnode_handle_put(fwnode: parent);
446
447 /* Guess something if prefix was NULL. */
448 return prefix ?: "/";
449}
450
451static struct fwnode_handle *
452software_node_get_parent(const struct fwnode_handle *fwnode)
453{
454 struct swnode *swnode = to_swnode(fwnode);
455
456 if (!swnode || !swnode->parent)
457 return NULL;
458
459 return fwnode_handle_get(fwnode: &swnode->parent->fwnode);
460}
461
462static struct fwnode_handle *
463software_node_get_next_child(const struct fwnode_handle *fwnode,
464 struct fwnode_handle *child)
465{
466 struct swnode *p = to_swnode(fwnode);
467 struct swnode *c = to_swnode(child);
468
469 if (!p || list_empty(head: &p->children) ||
470 (c && list_is_last(list: &c->entry, head: &p->children))) {
471 fwnode_handle_put(fwnode: child);
472 return NULL;
473 }
474
475 if (c)
476 c = list_next_entry(c, entry);
477 else
478 c = list_first_entry(&p->children, struct swnode, entry);
479
480 fwnode_handle_put(fwnode: child);
481 return fwnode_handle_get(fwnode: &c->fwnode);
482}
483
484static struct fwnode_handle *
485software_node_get_named_child_node(const struct fwnode_handle *fwnode,
486 const char *childname)
487{
488 struct swnode *swnode = to_swnode(fwnode);
489 struct swnode *child;
490
491 if (!swnode || list_empty(head: &swnode->children))
492 return NULL;
493
494 list_for_each_entry(child, &swnode->children, entry) {
495 if (!strcmp(childname, kobject_name(kobj: &child->kobj))) {
496 kobject_get(kobj: &child->kobj);
497 return &child->fwnode;
498 }
499 }
500 return NULL;
501}
502
503static int
504software_node_get_reference_args(const struct fwnode_handle *fwnode,
505 const char *propname, const char *nargs_prop,
506 unsigned int nargs, unsigned int index,
507 struct fwnode_reference_args *args)
508{
509 struct swnode *swnode = to_swnode(fwnode);
510 const struct software_node_ref_args *ref_array;
511 const struct software_node_ref_args *ref;
512 const struct property_entry *prop;
513 struct fwnode_handle *refnode;
514 u32 nargs_prop_val;
515 int error;
516 int i;
517
518 prop = property_entry_get(prop: swnode->node->properties, name: propname);
519 if (!prop)
520 return -ENOENT;
521
522 if (prop->type != DEV_PROP_REF)
523 return -EINVAL;
524
525 /*
526 * We expect that references are never stored inline, even
527 * single ones, as they are too big.
528 */
529 if (prop->is_inline)
530 return -EINVAL;
531
532 if ((index + 1) * sizeof(*ref) > prop->length)
533 return -ENOENT;
534
535 ref_array = prop->pointer;
536 ref = &ref_array[index];
537
538 refnode = software_node_fwnode(ref->node);
539 if (!refnode)
540 return -ENOENT;
541
542 if (nargs_prop) {
543 error = property_entry_read_int_array(props: ref->node->properties,
544 name: nargs_prop, elem_size: sizeof(u32),
545 val: &nargs_prop_val, nval: 1);
546 if (error)
547 return error;
548
549 nargs = nargs_prop_val;
550 }
551
552 if (nargs > NR_FWNODE_REFERENCE_ARGS)
553 return -EINVAL;
554
555 if (!args)
556 return 0;
557
558 args->fwnode = software_node_get(fwnode: refnode);
559 args->nargs = nargs;
560
561 for (i = 0; i < nargs; i++)
562 args->args[i] = ref->args[i];
563
564 return 0;
565}
566
567static struct fwnode_handle *
568swnode_graph_find_next_port(const struct fwnode_handle *parent,
569 struct fwnode_handle *port)
570{
571 struct fwnode_handle *old = port;
572
573 while ((port = software_node_get_next_child(fwnode: parent, child: old))) {
574 /*
575 * fwnode ports have naming style "port@", so we search for any
576 * children that follow that convention.
577 */
578 if (!strncmp(to_swnode(port)->node->name, "port@",
579 strlen("port@")))
580 return port;
581 old = port;
582 }
583
584 return NULL;
585}
586
587static struct fwnode_handle *
588software_node_graph_get_next_endpoint(const struct fwnode_handle *fwnode,
589 struct fwnode_handle *endpoint)
590{
591 struct swnode *swnode = to_swnode(fwnode);
592 struct fwnode_handle *parent;
593 struct fwnode_handle *port;
594
595 if (!swnode)
596 return NULL;
597
598 if (endpoint) {
599 port = software_node_get_parent(fwnode: endpoint);
600 parent = software_node_get_parent(fwnode: port);
601 } else {
602 parent = software_node_get_named_child_node(fwnode, childname: "ports");
603 if (!parent)
604 parent = software_node_get(fwnode: &swnode->fwnode);
605
606 port = swnode_graph_find_next_port(parent, NULL);
607 }
608
609 for (; port; port = swnode_graph_find_next_port(parent, port)) {
610 endpoint = software_node_get_next_child(fwnode: port, child: endpoint);
611 if (endpoint) {
612 fwnode_handle_put(fwnode: port);
613 break;
614 }
615 }
616
617 fwnode_handle_put(fwnode: parent);
618
619 return endpoint;
620}
621
622static struct fwnode_handle *
623software_node_graph_get_remote_endpoint(const struct fwnode_handle *fwnode)
624{
625 struct swnode *swnode = to_swnode(fwnode);
626 const struct software_node_ref_args *ref;
627 const struct property_entry *prop;
628
629 if (!swnode)
630 return NULL;
631
632 prop = property_entry_get(prop: swnode->node->properties, name: "remote-endpoint");
633 if (!prop || prop->type != DEV_PROP_REF || prop->is_inline)
634 return NULL;
635
636 ref = prop->pointer;
637
638 return software_node_get(fwnode: software_node_fwnode(ref[0].node));
639}
640
641static struct fwnode_handle *
642software_node_graph_get_port_parent(struct fwnode_handle *fwnode)
643{
644 struct swnode *swnode = to_swnode(fwnode);
645
646 swnode = swnode->parent;
647 if (swnode && !strcmp(swnode->node->name, "ports"))
648 swnode = swnode->parent;
649
650 return swnode ? software_node_get(fwnode: &swnode->fwnode) : NULL;
651}
652
653static int
654software_node_graph_parse_endpoint(const struct fwnode_handle *fwnode,
655 struct fwnode_endpoint *endpoint)
656{
657 struct swnode *swnode = to_swnode(fwnode);
658 const char *parent_name = swnode->parent->node->name;
659 int ret;
660
661 if (strlen("port@") >= strlen(parent_name) ||
662 strncmp(parent_name, "port@", strlen("port@")))
663 return -EINVAL;
664
665 /* Ports have naming style "port@n", we need to select the n */
666 ret = kstrtou32(s: parent_name + strlen("port@"), base: 10, res: &endpoint->port);
667 if (ret)
668 return ret;
669
670 endpoint->id = swnode->id;
671 endpoint->local_fwnode = fwnode;
672
673 return 0;
674}
675
676static const struct fwnode_operations software_node_ops = {
677 .get = software_node_get,
678 .put = software_node_put,
679 .property_present = software_node_property_present,
680 .property_read_bool = software_node_property_present,
681 .property_read_int_array = software_node_read_int_array,
682 .property_read_string_array = software_node_read_string_array,
683 .get_name = software_node_get_name,
684 .get_name_prefix = software_node_get_name_prefix,
685 .get_parent = software_node_get_parent,
686 .get_next_child_node = software_node_get_next_child,
687 .get_named_child_node = software_node_get_named_child_node,
688 .get_reference_args = software_node_get_reference_args,
689 .graph_get_next_endpoint = software_node_graph_get_next_endpoint,
690 .graph_get_remote_endpoint = software_node_graph_get_remote_endpoint,
691 .graph_get_port_parent = software_node_graph_get_port_parent,
692 .graph_parse_endpoint = software_node_graph_parse_endpoint,
693};
694
695/* -------------------------------------------------------------------------- */
696
697/**
698 * software_node_find_by_name - Find software node by name
699 * @parent: Parent of the software node
700 * @name: Name of the software node
701 *
702 * The function will find a node that is child of @parent and that is named
703 * @name. If no node is found, the function returns NULL.
704 *
705 * NOTE: you will need to drop the reference with fwnode_handle_put() after use.
706 */
707const struct software_node *
708software_node_find_by_name(const struct software_node *parent, const char *name)
709{
710 struct swnode *swnode = NULL;
711 struct kobject *k;
712
713 if (!name)
714 return NULL;
715
716 spin_lock(lock: &swnode_kset->list_lock);
717
718 list_for_each_entry(k, &swnode_kset->list, entry) {
719 swnode = kobj_to_swnode(k);
720 if (parent == swnode->node->parent && swnode->node->name &&
721 !strcmp(name, swnode->node->name)) {
722 kobject_get(kobj: &swnode->kobj);
723 break;
724 }
725 swnode = NULL;
726 }
727
728 spin_unlock(lock: &swnode_kset->list_lock);
729
730 return swnode ? swnode->node : NULL;
731}
732EXPORT_SYMBOL_GPL(software_node_find_by_name);
733
734static struct software_node *software_node_alloc(const struct property_entry *properties)
735{
736 struct property_entry *props;
737 struct software_node *node;
738
739 props = property_entries_dup(properties);
740 if (IS_ERR(ptr: props))
741 return ERR_CAST(ptr: props);
742
743 node = kzalloc(sizeof(*node), GFP_KERNEL);
744 if (!node) {
745 property_entries_free(props);
746 return ERR_PTR(error: -ENOMEM);
747 }
748
749 node->properties = props;
750
751 return node;
752}
753
754static void software_node_free(const struct software_node *node)
755{
756 property_entries_free(node->properties);
757 kfree(objp: node);
758}
759
760static void software_node_release(struct kobject *kobj)
761{
762 struct swnode *swnode = kobj_to_swnode(kobj);
763
764 if (swnode->parent) {
765 ida_free(&swnode->parent->child_ids, id: swnode->id);
766 list_del(entry: &swnode->entry);
767 } else {
768 ida_free(&swnode_root_ids, id: swnode->id);
769 }
770
771 if (swnode->allocated)
772 software_node_free(node: swnode->node);
773
774 ida_destroy(ida: &swnode->child_ids);
775 kfree(objp: swnode);
776}
777
778static const struct kobj_type software_node_type = {
779 .release = software_node_release,
780 .sysfs_ops = &kobj_sysfs_ops,
781};
782
783static struct fwnode_handle *
784swnode_register(const struct software_node *node, struct swnode *parent,
785 unsigned int allocated)
786{
787 struct swnode *swnode;
788 int ret;
789
790 swnode = kzalloc(sizeof(*swnode), GFP_KERNEL);
791 if (!swnode)
792 return ERR_PTR(error: -ENOMEM);
793
794 ret = ida_alloc(ida: parent ? &parent->child_ids : &swnode_root_ids,
795 GFP_KERNEL);
796 if (ret < 0) {
797 kfree(objp: swnode);
798 return ERR_PTR(error: ret);
799 }
800
801 swnode->id = ret;
802 swnode->node = node;
803 swnode->parent = parent;
804 swnode->kobj.kset = swnode_kset;
805 fwnode_init(fwnode: &swnode->fwnode, ops: &software_node_ops);
806
807 ida_init(ida: &swnode->child_ids);
808 INIT_LIST_HEAD(list: &swnode->entry);
809 INIT_LIST_HEAD(list: &swnode->children);
810
811 if (node->name)
812 ret = kobject_init_and_add(kobj: &swnode->kobj, ktype: &software_node_type,
813 parent: parent ? &parent->kobj : NULL,
814 fmt: "%s", node->name);
815 else
816 ret = kobject_init_and_add(kobj: &swnode->kobj, ktype: &software_node_type,
817 parent: parent ? &parent->kobj : NULL,
818 fmt: "node%d", swnode->id);
819 if (ret) {
820 kobject_put(kobj: &swnode->kobj);
821 return ERR_PTR(error: ret);
822 }
823
824 /*
825 * Assign the flag only in the successful case, so
826 * the above kobject_put() won't mess up with properties.
827 */
828 swnode->allocated = allocated;
829
830 if (parent)
831 list_add_tail(new: &swnode->entry, head: &parent->children);
832
833 kobject_uevent(kobj: &swnode->kobj, action: KOBJ_ADD);
834 return &swnode->fwnode;
835}
836
837/**
838 * software_node_register_node_group - Register a group of software nodes
839 * @node_group: NULL terminated array of software node pointers to be registered
840 *
841 * Register multiple software nodes at once. If any node in the array
842 * has its .parent pointer set (which can only be to another software_node),
843 * then its parent **must** have been registered before it is; either outside
844 * of this function or by ordering the array such that parent comes before
845 * child.
846 */
847int software_node_register_node_group(const struct software_node * const *node_group)
848{
849 unsigned int i;
850 int ret;
851
852 if (!node_group)
853 return 0;
854
855 for (i = 0; node_group[i]; i++) {
856 ret = software_node_register(node: node_group[i]);
857 if (ret) {
858 software_node_unregister_node_group(node_group);
859 return ret;
860 }
861 }
862
863 return 0;
864}
865EXPORT_SYMBOL_GPL(software_node_register_node_group);
866
867/**
868 * software_node_unregister_node_group - Unregister a group of software nodes
869 * @node_group: NULL terminated array of software node pointers to be unregistered
870 *
871 * Unregister multiple software nodes at once. If parent pointers are set up
872 * in any of the software nodes then the array **must** be ordered such that
873 * parents come before their children.
874 *
875 * NOTE: If you are uncertain whether the array is ordered such that
876 * parents will be unregistered before their children, it is wiser to
877 * remove the nodes individually, in the correct order (child before
878 * parent).
879 */
880void software_node_unregister_node_group(const struct software_node * const *node_group)
881{
882 unsigned int i = 0;
883
884 if (!node_group)
885 return;
886
887 while (node_group[i])
888 i++;
889
890 while (i--)
891 software_node_unregister(node: node_group[i]);
892}
893EXPORT_SYMBOL_GPL(software_node_unregister_node_group);
894
895/**
896 * software_node_register - Register static software node
897 * @node: The software node to be registered
898 */
899int software_node_register(const struct software_node *node)
900{
901 struct swnode *parent = software_node_to_swnode(node: node->parent);
902
903 if (software_node_to_swnode(node))
904 return -EEXIST;
905
906 if (node->parent && !parent)
907 return -EINVAL;
908
909 return PTR_ERR_OR_ZERO(ptr: swnode_register(node, parent, allocated: 0));
910}
911EXPORT_SYMBOL_GPL(software_node_register);
912
913/**
914 * software_node_unregister - Unregister static software node
915 * @node: The software node to be unregistered
916 */
917void software_node_unregister(const struct software_node *node)
918{
919 struct swnode *swnode;
920
921 swnode = software_node_to_swnode(node);
922 if (swnode)
923 fwnode_remove_software_node(fwnode: &swnode->fwnode);
924}
925EXPORT_SYMBOL_GPL(software_node_unregister);
926
927struct fwnode_handle *
928fwnode_create_software_node(const struct property_entry *properties,
929 const struct fwnode_handle *parent)
930{
931 struct fwnode_handle *fwnode;
932 struct software_node *node;
933 struct swnode *p;
934
935 if (IS_ERR(ptr: parent))
936 return ERR_CAST(ptr: parent);
937
938 p = to_swnode(parent);
939 if (parent && !p)
940 return ERR_PTR(error: -EINVAL);
941
942 node = software_node_alloc(properties);
943 if (IS_ERR(ptr: node))
944 return ERR_CAST(ptr: node);
945
946 node->parent = p ? p->node : NULL;
947
948 fwnode = swnode_register(node, parent: p, allocated: 1);
949 if (IS_ERR(ptr: fwnode))
950 software_node_free(node);
951
952 return fwnode;
953}
954EXPORT_SYMBOL_GPL(fwnode_create_software_node);
955
956void fwnode_remove_software_node(struct fwnode_handle *fwnode)
957{
958 struct swnode *swnode = to_swnode(fwnode);
959
960 if (!swnode)
961 return;
962
963 kobject_put(kobj: &swnode->kobj);
964}
965EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
966
967/**
968 * device_add_software_node - Assign software node to a device
969 * @dev: The device the software node is meant for.
970 * @node: The software node.
971 *
972 * This function will make @node the secondary firmware node pointer of @dev. If
973 * @dev has no primary node, then @node will become the primary node. The
974 * function will register @node automatically if it wasn't already registered.
975 */
976int device_add_software_node(struct device *dev, const struct software_node *node)
977{
978 struct swnode *swnode;
979 int ret;
980
981 /* Only one software node per device. */
982 if (dev_to_swnode(dev))
983 return -EBUSY;
984
985 swnode = software_node_to_swnode(node);
986 if (swnode) {
987 kobject_get(kobj: &swnode->kobj);
988 } else {
989 ret = software_node_register(node);
990 if (ret)
991 return ret;
992
993 swnode = software_node_to_swnode(node);
994 }
995
996 set_secondary_fwnode(dev, fwnode: &swnode->fwnode);
997
998 /*
999 * If the device has been fully registered by the time this function is
1000 * called, software_node_notify() must be called separately so that the
1001 * symlinks get created and the reference count of the node is kept in
1002 * balance.
1003 */
1004 if (device_is_registered(dev))
1005 software_node_notify(dev);
1006
1007 return 0;
1008}
1009EXPORT_SYMBOL_GPL(device_add_software_node);
1010
1011/**
1012 * device_remove_software_node - Remove device's software node
1013 * @dev: The device with the software node.
1014 *
1015 * This function will unregister the software node of @dev.
1016 */
1017void device_remove_software_node(struct device *dev)
1018{
1019 struct swnode *swnode;
1020
1021 swnode = dev_to_swnode(dev);
1022 if (!swnode)
1023 return;
1024
1025 if (device_is_registered(dev))
1026 software_node_notify_remove(dev);
1027
1028 set_secondary_fwnode(dev, NULL);
1029 kobject_put(kobj: &swnode->kobj);
1030}
1031EXPORT_SYMBOL_GPL(device_remove_software_node);
1032
1033/**
1034 * device_create_managed_software_node - Create a software node for a device
1035 * @dev: The device the software node is assigned to.
1036 * @properties: Device properties for the software node.
1037 * @parent: Parent of the software node.
1038 *
1039 * Creates a software node as a managed resource for @dev, which means the
1040 * lifetime of the newly created software node is tied to the lifetime of @dev.
1041 * Software nodes created with this function should not be reused or shared
1042 * because of that. The function takes a deep copy of @properties for the
1043 * software node.
1044 *
1045 * Since the new software node is assigned directly to @dev, and since it should
1046 * not be shared, it is not returned to the caller. The function returns 0 on
1047 * success, and errno in case of an error.
1048 */
1049int device_create_managed_software_node(struct device *dev,
1050 const struct property_entry *properties,
1051 const struct software_node *parent)
1052{
1053 struct fwnode_handle *p = software_node_fwnode(parent);
1054 struct fwnode_handle *fwnode;
1055
1056 if (parent && !p)
1057 return -EINVAL;
1058
1059 fwnode = fwnode_create_software_node(properties, p);
1060 if (IS_ERR(ptr: fwnode))
1061 return PTR_ERR(ptr: fwnode);
1062
1063 to_swnode(fwnode)->managed = true;
1064 set_secondary_fwnode(dev, fwnode);
1065
1066 if (device_is_registered(dev))
1067 software_node_notify(dev);
1068
1069 return 0;
1070}
1071EXPORT_SYMBOL_GPL(device_create_managed_software_node);
1072
1073void software_node_notify(struct device *dev)
1074{
1075 struct swnode *swnode;
1076 int ret;
1077
1078 swnode = dev_to_swnode(dev);
1079 if (!swnode)
1080 return;
1081
1082 kobject_get(kobj: &swnode->kobj);
1083 ret = sysfs_create_link(kobj: &dev->kobj, target: &swnode->kobj, name: "software_node");
1084 if (ret)
1085 return;
1086
1087 ret = sysfs_create_link(kobj: &swnode->kobj, target: &dev->kobj, name: dev_name(dev));
1088 if (ret) {
1089 sysfs_remove_link(kobj: &dev->kobj, name: "software_node");
1090 return;
1091 }
1092}
1093
1094void software_node_notify_remove(struct device *dev)
1095{
1096 struct swnode *swnode;
1097
1098 swnode = dev_to_swnode(dev);
1099 if (!swnode)
1100 return;
1101
1102 sysfs_remove_link(kobj: &swnode->kobj, name: dev_name(dev));
1103 sysfs_remove_link(kobj: &dev->kobj, name: "software_node");
1104 kobject_put(kobj: &swnode->kobj);
1105
1106 if (swnode->managed) {
1107 set_secondary_fwnode(dev, NULL);
1108 kobject_put(kobj: &swnode->kobj);
1109 }
1110}
1111
1112static int __init software_node_init(void)
1113{
1114 swnode_kset = kset_create_and_add(name: "software_nodes", NULL, parent_kobj: kernel_kobj);
1115 if (!swnode_kset)
1116 return -ENOMEM;
1117 return 0;
1118}
1119postcore_initcall(software_node_init);
1120
1121static void __exit software_node_exit(void)
1122{
1123 ida_destroy(ida: &swnode_root_ids);
1124 kset_unregister(kset: swnode_kset);
1125}
1126__exitcall(software_node_exit);
1127