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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(const struct fwnode_handle *fwnode)
75{
76 const 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 const void *property_get_pointer(const struct property_entry *prop)
107{
108 if (!prop->length)
109 return NULL;
110
111 return prop->is_inline ? &prop->value : prop->pointer;
112}
113
114static const void *property_entry_find(const struct property_entry *props,
115 const char *propname, size_t length)
116{
117 const struct property_entry *prop;
118 const void *pointer;
119
120 prop = property_entry_get(props, propname);
121 if (!prop)
122 return ERR_PTR(-EINVAL);
123 pointer = property_get_pointer(prop);
124 if (!pointer)
125 return ERR_PTR(-ENODATA);
126 if (length > prop->length)
127 return ERR_PTR(-EOVERFLOW);
128 return pointer;
129}
130
131static int
132property_entry_count_elems_of_size(const struct property_entry *props,
133 const char *propname, size_t length)
134{
135 const struct property_entry *prop;
136
137 prop = property_entry_get(props, propname);
138 if (!prop)
139 return -EINVAL;
140
141 return prop->length / length;
142}
143
144static int property_entry_read_int_array(const struct property_entry *props,
145 const char *name,
146 unsigned int elem_size, void *val,
147 size_t nval)
148{
149 const void *pointer;
150 size_t length;
151
152 if (!val)
153 return property_entry_count_elems_of_size(props, name,
154 elem_size);
155
156 if (!is_power_of_2(elem_size) || elem_size > sizeof(u64))
157 return -ENXIO;
158
159 length = nval * elem_size;
160
161 pointer = property_entry_find(props, name, length);
162 if (IS_ERR(pointer))
163 return PTR_ERR(pointer);
164
165 memcpy(val, pointer, length);
166 return 0;
167}
168
169static int property_entry_read_string_array(const struct property_entry *props,
170 const char *propname,
171 const char **strings, size_t nval)
172{
173 const void *pointer;
174 size_t length;
175 int array_len;
176
177 /* Find out the array length. */
178 array_len = property_entry_count_elems_of_size(props, propname,
179 sizeof(const char *));
180 if (array_len < 0)
181 return array_len;
182
183 /* Return how many there are if strings is NULL. */
184 if (!strings)
185 return array_len;
186
187 array_len = min_t(size_t, nval, array_len);
188 length = array_len * sizeof(*strings);
189
190 pointer = property_entry_find(props, propname, length);
191 if (IS_ERR(pointer))
192 return PTR_ERR(pointer);
193
194 memcpy(strings, pointer, length);
195
196 return array_len;
197}
198
199static void property_entry_free_data(const struct property_entry *p)
200{
201 const char * const *src_str;
202 size_t i, nval;
203
204 if (p->type == DEV_PROP_STRING) {
205 src_str = property_get_pointer(p);
206 nval = p->length / sizeof(*src_str);
207 for (i = 0; i < nval; i++)
208 kfree(src_str[i]);
209 }
210
211 if (!p->is_inline)
212 kfree(p->pointer);
213
214 kfree(p->name);
215}
216
217static bool property_copy_string_array(const char **dst_ptr,
218 const char * const *src_ptr,
219 size_t nval)
220{
221 int i;
222
223 for (i = 0; i < nval; i++) {
224 dst_ptr[i] = kstrdup(src_ptr[i], GFP_KERNEL);
225 if (!dst_ptr[i] && src_ptr[i]) {
226 while (--i >= 0)
227 kfree(dst_ptr[i]);
228 return false;
229 }
230 }
231
232 return true;
233}
234
235static int property_entry_copy_data(struct property_entry *dst,
236 const struct property_entry *src)
237{
238 const void *pointer = property_get_pointer(src);
239 void *dst_ptr;
240 size_t nval;
241
242 /*
243 * Properties with no data should not be marked as stored
244 * out of line.
245 */
246 if (!src->is_inline && !src->length)
247 return -ENODATA;
248
249 /*
250 * Reference properties are never stored inline as
251 * they are too big.
252 */
253 if (src->type == DEV_PROP_REF && src->is_inline)
254 return -EINVAL;
255
256 if (src->length <= sizeof(dst->value)) {
257 dst_ptr = &dst->value;
258 dst->is_inline = true;
259 } else {
260 dst_ptr = kmalloc(src->length, GFP_KERNEL);
261 if (!dst_ptr)
262 return -ENOMEM;
263 dst->pointer = dst_ptr;
264 }
265
266 if (src->type == DEV_PROP_STRING) {
267 nval = src->length / sizeof(const char *);
268 if (!property_copy_string_array(dst_ptr, pointer, nval)) {
269 if (!dst->is_inline)
270 kfree(dst->pointer);
271 return -ENOMEM;
272 }
273 } else {
274 memcpy(dst_ptr, pointer, src->length);
275 }
276
277 dst->length = src->length;
278 dst->type = src->type;
279 dst->name = kstrdup(src->name, GFP_KERNEL);
280 if (!dst->name) {
281 property_entry_free_data(dst);
282 return -ENOMEM;
283 }
284
285 return 0;
286}
287
288/**
289 * property_entries_dup - duplicate array of properties
290 * @properties: array of properties to copy
291 *
292 * This function creates a deep copy of the given NULL-terminated array
293 * of property entries.
294 */
295struct property_entry *
296property_entries_dup(const struct property_entry *properties)
297{
298 struct property_entry *p;
299 int i, n = 0;
300 int ret;
301
302 if (!properties)
303 return NULL;
304
305 while (properties[n].name)
306 n++;
307
308 p = kcalloc(n + 1, sizeof(*p), GFP_KERNEL);
309 if (!p)
310 return ERR_PTR(-ENOMEM);
311
312 for (i = 0; i < n; i++) {
313 ret = property_entry_copy_data(&p[i], &properties[i]);
314 if (ret) {
315 while (--i >= 0)
316 property_entry_free_data(&p[i]);
317 kfree(p);
318 return ERR_PTR(ret);
319 }
320 }
321
322 return p;
323}
324EXPORT_SYMBOL_GPL(property_entries_dup);
325
326/**
327 * property_entries_free - free previously allocated array of properties
328 * @properties: array of properties to destroy
329 *
330 * This function frees given NULL-terminated array of property entries,
331 * along with their data.
332 */
333void property_entries_free(const struct property_entry *properties)
334{
335 const struct property_entry *p;
336
337 if (!properties)
338 return;
339
340 for (p = properties; p->name; p++)
341 property_entry_free_data(p);
342
343 kfree(properties);
344}
345EXPORT_SYMBOL_GPL(property_entries_free);
346
347/* -------------------------------------------------------------------------- */
348/* fwnode operations */
349
350static struct fwnode_handle *software_node_get(struct fwnode_handle *fwnode)
351{
352 struct swnode *swnode = to_swnode(fwnode);
353
354 kobject_get(&swnode->kobj);
355
356 return &swnode->fwnode;
357}
358
359static void software_node_put(struct fwnode_handle *fwnode)
360{
361 struct swnode *swnode = to_swnode(fwnode);
362
363 kobject_put(&swnode->kobj);
364}
365
366static bool software_node_property_present(const struct fwnode_handle *fwnode,
367 const char *propname)
368{
369 struct swnode *swnode = to_swnode(fwnode);
370
371 return !!property_entry_get(swnode->node->properties, propname);
372}
373
374static int software_node_read_int_array(const struct fwnode_handle *fwnode,
375 const char *propname,
376 unsigned int elem_size, void *val,
377 size_t nval)
378{
379 struct swnode *swnode = to_swnode(fwnode);
380
381 return property_entry_read_int_array(swnode->node->properties, propname,
382 elem_size, val, nval);
383}
384
385static int software_node_read_string_array(const struct fwnode_handle *fwnode,
386 const char *propname,
387 const char **val, size_t nval)
388{
389 struct swnode *swnode = to_swnode(fwnode);
390
391 return property_entry_read_string_array(swnode->node->properties,
392 propname, val, nval);
393}
394
395static const char *
396software_node_get_name(const struct fwnode_handle *fwnode)
397{
398 const struct swnode *swnode = to_swnode(fwnode);
399
400 if (!swnode)
401 return "(null)";
402
403 return kobject_name(&swnode->kobj);
404}
405
406static const char *
407software_node_get_name_prefix(const struct fwnode_handle *fwnode)
408{
409 struct fwnode_handle *parent;
410 const char *prefix;
411
412 parent = fwnode_get_parent(fwnode);
413 if (!parent)
414 return "";
415
416 /* Figure out the prefix from the parents. */
417 while (is_software_node(parent))
418 parent = fwnode_get_next_parent(parent);
419
420 prefix = fwnode_get_name_prefix(parent);
421 fwnode_handle_put(parent);
422
423 /* Guess something if prefix was NULL. */
424 return prefix ?: "/";
425}
426
427static struct fwnode_handle *
428software_node_get_parent(const struct fwnode_handle *fwnode)
429{
430 struct swnode *swnode = to_swnode(fwnode);
431
432 if (!swnode || !swnode->parent)
433 return NULL;
434
435 return fwnode_handle_get(&swnode->parent->fwnode);
436}
437
438static struct fwnode_handle *
439software_node_get_next_child(const struct fwnode_handle *fwnode,
440 struct fwnode_handle *child)
441{
442 struct swnode *p = to_swnode(fwnode);
443 struct swnode *c = to_swnode(child);
444
445 if (!p || list_empty(&p->children) ||
446 (c && list_is_last(&c->entry, &p->children)))
447 return NULL;
448
449 if (c)
450 c = list_next_entry(c, entry);
451 else
452 c = list_first_entry(&p->children, struct swnode, entry);
453 return &c->fwnode;
454}
455
456static struct fwnode_handle *
457software_node_get_named_child_node(const struct fwnode_handle *fwnode,
458 const char *childname)
459{
460 struct swnode *swnode = to_swnode(fwnode);
461 struct swnode *child;
462
463 if (!swnode || list_empty(&swnode->children))
464 return NULL;
465
466 list_for_each_entry(child, &swnode->children, entry) {
467 if (!strcmp(childname, kobject_name(&child->kobj))) {
468 kobject_get(&child->kobj);
469 return &child->fwnode;
470 }
471 }
472 return NULL;
473}
474
475static int
476software_node_get_reference_args(const struct fwnode_handle *fwnode,
477 const char *propname, const char *nargs_prop,
478 unsigned int nargs, unsigned int index,
479 struct fwnode_reference_args *args)
480{
481 struct swnode *swnode = to_swnode(fwnode);
482 const struct software_node_ref_args *ref_array;
483 const struct software_node_ref_args *ref;
484 const struct property_entry *prop;
485 struct fwnode_handle *refnode;
486 u32 nargs_prop_val;
487 int error;
488 int i;
489
490 if (!swnode)
491 return -ENOENT;
492
493 prop = property_entry_get(swnode->node->properties, propname);
494 if (!prop)
495 return -ENOENT;
496
497 if (prop->type != DEV_PROP_REF)
498 return -EINVAL;
499
500 /*
501 * We expect that references are never stored inline, even
502 * single ones, as they are too big.
503 */
504 if (prop->is_inline)
505 return -EINVAL;
506
507 if (index * sizeof(*ref) >= prop->length)
508 return -ENOENT;
509
510 ref_array = prop->pointer;
511 ref = &ref_array[index];
512
513 refnode = software_node_fwnode(ref->node);
514 if (!refnode)
515 return -ENOENT;
516
517 if (nargs_prop) {
518 error = property_entry_read_int_array(swnode->node->properties,
519 nargs_prop, sizeof(u32),
520 &nargs_prop_val, 1);
521 if (error)
522 return error;
523
524 nargs = nargs_prop_val;
525 }
526
527 if (nargs > NR_FWNODE_REFERENCE_ARGS)
528 return -EINVAL;
529
530 args->fwnode = software_node_get(refnode);
531 args->nargs = nargs;
532
533 for (i = 0; i < nargs; i++)
534 args->args[i] = ref->args[i];
535
536 return 0;
537}
538
539static const struct fwnode_operations software_node_ops = {
540 .get = software_node_get,
541 .put = software_node_put,
542 .property_present = software_node_property_present,
543 .property_read_int_array = software_node_read_int_array,
544 .property_read_string_array = software_node_read_string_array,
545 .get_name = software_node_get_name,
546 .get_name_prefix = software_node_get_name_prefix,
547 .get_parent = software_node_get_parent,
548 .get_next_child_node = software_node_get_next_child,
549 .get_named_child_node = software_node_get_named_child_node,
550 .get_reference_args = software_node_get_reference_args
551};
552
553/* -------------------------------------------------------------------------- */
554
555/**
556 * software_node_find_by_name - Find software node by name
557 * @parent: Parent of the software node
558 * @name: Name of the software node
559 *
560 * The function will find a node that is child of @parent and that is named
561 * @name. If no node is found, the function returns NULL.
562 *
563 * NOTE: you will need to drop the reference with fwnode_handle_put() after use.
564 */
565const struct software_node *
566software_node_find_by_name(const struct software_node *parent, const char *name)
567{
568 struct swnode *swnode = NULL;
569 struct kobject *k;
570
571 if (!name)
572 return NULL;
573
574 spin_lock(&swnode_kset->list_lock);
575
576 list_for_each_entry(k, &swnode_kset->list, entry) {
577 swnode = kobj_to_swnode(k);
578 if (parent == swnode->node->parent && swnode->node->name &&
579 !strcmp(name, swnode->node->name)) {
580 kobject_get(&swnode->kobj);
581 break;
582 }
583 swnode = NULL;
584 }
585
586 spin_unlock(&swnode_kset->list_lock);
587
588 return swnode ? swnode->node : NULL;
589}
590EXPORT_SYMBOL_GPL(software_node_find_by_name);
591
592static int
593software_node_register_properties(struct software_node *node,
594 const struct property_entry *properties)
595{
596 struct property_entry *props;
597
598 props = property_entries_dup(properties);
599 if (IS_ERR(props))
600 return PTR_ERR(props);
601
602 node->properties = props;
603
604 return 0;
605}
606
607static void software_node_release(struct kobject *kobj)
608{
609 struct swnode *swnode = kobj_to_swnode(kobj);
610
611 if (swnode->parent) {
612 ida_simple_remove(&swnode->parent->child_ids, swnode->id);
613 list_del(&swnode->entry);
614 } else {
615 ida_simple_remove(&swnode_root_ids, swnode->id);
616 }
617
618 if (swnode->allocated) {
619 property_entries_free(swnode->node->properties);
620 kfree(swnode->node);
621 }
622 ida_destroy(&swnode->child_ids);
623 kfree(swnode);
624}
625
626static struct kobj_type software_node_type = {
627 .release = software_node_release,
628 .sysfs_ops = &kobj_sysfs_ops,
629};
630
631static struct fwnode_handle *
632swnode_register(const struct software_node *node, struct swnode *parent,
633 unsigned int allocated)
634{
635 struct swnode *swnode;
636 int ret;
637
638 swnode = kzalloc(sizeof(*swnode), GFP_KERNEL);
639 if (!swnode) {
640 ret = -ENOMEM;
641 goto out_err;
642 }
643
644 ret = ida_simple_get(parent ? &parent->child_ids : &swnode_root_ids,
645 0, 0, GFP_KERNEL);
646 if (ret < 0) {
647 kfree(swnode);
648 goto out_err;
649 }
650
651 swnode->id = ret;
652 swnode->node = node;
653 swnode->parent = parent;
654 swnode->allocated = allocated;
655 swnode->kobj.kset = swnode_kset;
656 swnode->fwnode.ops = &software_node_ops;
657
658 ida_init(&swnode->child_ids);
659 INIT_LIST_HEAD(&swnode->entry);
660 INIT_LIST_HEAD(&swnode->children);
661
662 if (node->name)
663 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
664 parent ? &parent->kobj : NULL,
665 "%s", node->name);
666 else
667 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
668 parent ? &parent->kobj : NULL,
669 "node%d", swnode->id);
670 if (ret) {
671 kobject_put(&swnode->kobj);
672 return ERR_PTR(ret);
673 }
674
675 if (parent)
676 list_add_tail(&swnode->entry, &parent->children);
677
678 kobject_uevent(&swnode->kobj, KOBJ_ADD);
679 return &swnode->fwnode;
680
681out_err:
682 if (allocated)
683 property_entries_free(node->properties);
684 return ERR_PTR(ret);
685}
686
687/**
688 * software_node_register_nodes - Register an array of software nodes
689 * @nodes: Zero terminated array of software nodes to be registered
690 *
691 * Register multiple software nodes at once.
692 */
693int software_node_register_nodes(const struct software_node *nodes)
694{
695 int ret;
696 int i;
697
698 for (i = 0; nodes[i].name; i++) {
699 ret = software_node_register(&nodes[i]);
700 if (ret) {
701 software_node_unregister_nodes(nodes);
702 return ret;
703 }
704 }
705
706 return 0;
707}
708EXPORT_SYMBOL_GPL(software_node_register_nodes);
709
710/**
711 * software_node_unregister_nodes - Unregister an array of software nodes
712 * @nodes: Zero terminated array of software nodes to be unregistered
713 *
714 * Unregister multiple software nodes at once.
715 *
716 * NOTE: Be careful using this call if the nodes had parent pointers set up in
717 * them before registering. If so, it is wiser to remove the nodes
718 * individually, in the correct order (child before parent) instead of relying
719 * on the sequential order of the list of nodes in the array.
720 */
721void software_node_unregister_nodes(const struct software_node *nodes)
722{
723 int i;
724
725 for (i = 0; nodes[i].name; i++)
726 software_node_unregister(&nodes[i]);
727}
728EXPORT_SYMBOL_GPL(software_node_unregister_nodes);
729
730/**
731 * software_node_register_node_group - Register a group of software nodes
732 * @node_group: NULL terminated array of software node pointers to be registered
733 *
734 * Register multiple software nodes at once.
735 */
736int software_node_register_node_group(const struct software_node **node_group)
737{
738 unsigned int i;
739 int ret;
740
741 if (!node_group)
742 return 0;
743
744 for (i = 0; node_group[i]; i++) {
745 ret = software_node_register(node_group[i]);
746 if (ret) {
747 software_node_unregister_node_group(node_group);
748 return ret;
749 }
750 }
751
752 return 0;
753}
754EXPORT_SYMBOL_GPL(software_node_register_node_group);
755
756/**
757 * software_node_unregister_node_group - Unregister a group of software nodes
758 * @node_group: NULL terminated array of software node pointers to be unregistered
759 *
760 * Unregister multiple software nodes at once.
761 */
762void software_node_unregister_node_group(const struct software_node **node_group)
763{
764 unsigned int i;
765
766 if (!node_group)
767 return;
768
769 for (i = 0; node_group[i]; i++)
770 software_node_unregister(node_group[i]);
771}
772EXPORT_SYMBOL_GPL(software_node_unregister_node_group);
773
774/**
775 * software_node_register - Register static software node
776 * @node: The software node to be registered
777 */
778int software_node_register(const struct software_node *node)
779{
780 struct swnode *parent = software_node_to_swnode(node->parent);
781
782 if (software_node_to_swnode(node))
783 return -EEXIST;
784
785 return PTR_ERR_OR_ZERO(swnode_register(node, parent, 0));
786}
787EXPORT_SYMBOL_GPL(software_node_register);
788
789/**
790 * software_node_unregister - Unregister static software node
791 * @node: The software node to be unregistered
792 */
793void software_node_unregister(const struct software_node *node)
794{
795 struct swnode *swnode;
796
797 swnode = software_node_to_swnode(node);
798 if (swnode)
799 fwnode_remove_software_node(&swnode->fwnode);
800}
801EXPORT_SYMBOL_GPL(software_node_unregister);
802
803struct fwnode_handle *
804fwnode_create_software_node(const struct property_entry *properties,
805 const struct fwnode_handle *parent)
806{
807 struct software_node *node;
808 struct swnode *p = NULL;
809 int ret;
810
811 if (parent) {
812 if (IS_ERR(parent))
813 return ERR_CAST(parent);
814 if (!is_software_node(parent))
815 return ERR_PTR(-EINVAL);
816 p = to_swnode(parent);
817 }
818
819 node = kzalloc(sizeof(*node), GFP_KERNEL);
820 if (!node)
821 return ERR_PTR(-ENOMEM);
822
823 ret = software_node_register_properties(node, properties);
824 if (ret) {
825 kfree(node);
826 return ERR_PTR(ret);
827 }
828
829 node->parent = p ? p->node : NULL;
830
831 return swnode_register(node, p, 1);
832}
833EXPORT_SYMBOL_GPL(fwnode_create_software_node);
834
835void fwnode_remove_software_node(struct fwnode_handle *fwnode)
836{
837 struct swnode *swnode = to_swnode(fwnode);
838
839 if (!swnode)
840 return;
841
842 kobject_put(&swnode->kobj);
843}
844EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
845
846int software_node_notify(struct device *dev, unsigned long action)
847{
848 struct fwnode_handle *fwnode = dev_fwnode(dev);
849 struct swnode *swnode;
850 int ret;
851
852 if (!fwnode)
853 return 0;
854
855 if (!is_software_node(fwnode))
856 fwnode = fwnode->secondary;
857 if (!is_software_node(fwnode))
858 return 0;
859
860 swnode = to_swnode(fwnode);
861
862 switch (action) {
863 case KOBJ_ADD:
864 ret = sysfs_create_link(&dev->kobj, &swnode->kobj,
865 "software_node");
866 if (ret)
867 break;
868
869 ret = sysfs_create_link(&swnode->kobj, &dev->kobj,
870 dev_name(dev));
871 if (ret) {
872 sysfs_remove_link(&dev->kobj, "software_node");
873 break;
874 }
875 kobject_get(&swnode->kobj);
876 break;
877 case KOBJ_REMOVE:
878 sysfs_remove_link(&swnode->kobj, dev_name(dev));
879 sysfs_remove_link(&dev->kobj, "software_node");
880 kobject_put(&swnode->kobj);
881 break;
882 default:
883 break;
884 }
885
886 return 0;
887}
888
889static int __init software_node_init(void)
890{
891 swnode_kset = kset_create_and_add("software_nodes", NULL, kernel_kobj);
892 if (!swnode_kset)
893 return -ENOMEM;
894 return 0;
895}
896postcore_initcall(software_node_init);
897
898static void __exit software_node_exit(void)
899{
900 ida_destroy(&swnode_root_ids);
901 kset_unregister(swnode_kset);
902}
903__exitcall(software_node_exit);
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 struct kobject kobj;
16 struct fwnode_handle fwnode;
17 const struct software_node *node;
18 int id;
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 unsigned int managed:1;
28};
29
30static DEFINE_IDA(swnode_root_ids);
31static struct kset *swnode_kset;
32
33#define kobj_to_swnode(_kobj_) container_of(_kobj_, struct swnode, kobj)
34
35static const struct fwnode_operations software_node_ops;
36
37bool is_software_node(const struct fwnode_handle *fwnode)
38{
39 return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &software_node_ops;
40}
41EXPORT_SYMBOL_GPL(is_software_node);
42
43#define to_swnode(__fwnode) \
44 ({ \
45 typeof(__fwnode) __to_swnode_fwnode = __fwnode; \
46 \
47 is_software_node(__to_swnode_fwnode) ? \
48 container_of(__to_swnode_fwnode, \
49 struct swnode, fwnode) : NULL; \
50 })
51
52static inline struct swnode *dev_to_swnode(struct device *dev)
53{
54 struct fwnode_handle *fwnode = dev_fwnode(dev);
55
56 if (!fwnode)
57 return NULL;
58
59 if (!is_software_node(fwnode))
60 fwnode = fwnode->secondary;
61
62 return to_swnode(fwnode);
63}
64
65static struct swnode *
66software_node_to_swnode(const struct software_node *node)
67{
68 struct swnode *swnode = NULL;
69 struct kobject *k;
70
71 if (!node)
72 return NULL;
73
74 spin_lock(&swnode_kset->list_lock);
75
76 list_for_each_entry(k, &swnode_kset->list, entry) {
77 swnode = kobj_to_swnode(k);
78 if (swnode->node == node)
79 break;
80 swnode = NULL;
81 }
82
83 spin_unlock(&swnode_kset->list_lock);
84
85 return swnode;
86}
87
88const struct software_node *to_software_node(const struct fwnode_handle *fwnode)
89{
90 const struct swnode *swnode = to_swnode(fwnode);
91
92 return swnode ? swnode->node : NULL;
93}
94EXPORT_SYMBOL_GPL(to_software_node);
95
96struct fwnode_handle *software_node_fwnode(const struct software_node *node)
97{
98 struct swnode *swnode = software_node_to_swnode(node);
99
100 return swnode ? &swnode->fwnode : NULL;
101}
102EXPORT_SYMBOL_GPL(software_node_fwnode);
103
104/* -------------------------------------------------------------------------- */
105/* property_entry processing */
106
107static const struct property_entry *
108property_entry_get(const struct property_entry *prop, const char *name)
109{
110 if (!prop)
111 return NULL;
112
113 for (; prop->name; prop++)
114 if (!strcmp(name, prop->name))
115 return prop;
116
117 return NULL;
118}
119
120static const void *property_get_pointer(const struct property_entry *prop)
121{
122 if (!prop->length)
123 return NULL;
124
125 return prop->is_inline ? &prop->value : prop->pointer;
126}
127
128static const void *property_entry_find(const struct property_entry *props,
129 const char *propname, size_t length)
130{
131 const struct property_entry *prop;
132 const void *pointer;
133
134 prop = property_entry_get(props, propname);
135 if (!prop)
136 return ERR_PTR(-EINVAL);
137 pointer = property_get_pointer(prop);
138 if (!pointer)
139 return ERR_PTR(-ENODATA);
140 if (length > prop->length)
141 return ERR_PTR(-EOVERFLOW);
142 return pointer;
143}
144
145static int
146property_entry_count_elems_of_size(const struct property_entry *props,
147 const char *propname, size_t length)
148{
149 const struct property_entry *prop;
150
151 prop = property_entry_get(props, propname);
152 if (!prop)
153 return -EINVAL;
154
155 return prop->length / length;
156}
157
158static int property_entry_read_int_array(const struct property_entry *props,
159 const char *name,
160 unsigned int elem_size, void *val,
161 size_t nval)
162{
163 const void *pointer;
164 size_t length;
165
166 if (!val)
167 return property_entry_count_elems_of_size(props, name,
168 elem_size);
169
170 if (!is_power_of_2(elem_size) || elem_size > sizeof(u64))
171 return -ENXIO;
172
173 length = nval * elem_size;
174
175 pointer = property_entry_find(props, name, length);
176 if (IS_ERR(pointer))
177 return PTR_ERR(pointer);
178
179 memcpy(val, pointer, length);
180 return 0;
181}
182
183static int property_entry_read_string_array(const struct property_entry *props,
184 const char *propname,
185 const char **strings, size_t nval)
186{
187 const void *pointer;
188 size_t length;
189 int array_len;
190
191 /* Find out the array length. */
192 array_len = property_entry_count_elems_of_size(props, propname,
193 sizeof(const char *));
194 if (array_len < 0)
195 return array_len;
196
197 /* Return how many there are if strings is NULL. */
198 if (!strings)
199 return array_len;
200
201 array_len = min_t(size_t, nval, array_len);
202 length = array_len * sizeof(*strings);
203
204 pointer = property_entry_find(props, propname, length);
205 if (IS_ERR(pointer))
206 return PTR_ERR(pointer);
207
208 memcpy(strings, pointer, length);
209
210 return array_len;
211}
212
213static void property_entry_free_data(const struct property_entry *p)
214{
215 const char * const *src_str;
216 size_t i, nval;
217
218 if (p->type == DEV_PROP_STRING) {
219 src_str = property_get_pointer(p);
220 nval = p->length / sizeof(*src_str);
221 for (i = 0; i < nval; i++)
222 kfree(src_str[i]);
223 }
224
225 if (!p->is_inline)
226 kfree(p->pointer);
227
228 kfree(p->name);
229}
230
231static bool property_copy_string_array(const char **dst_ptr,
232 const char * const *src_ptr,
233 size_t nval)
234{
235 int i;
236
237 for (i = 0; i < nval; i++) {
238 dst_ptr[i] = kstrdup(src_ptr[i], GFP_KERNEL);
239 if (!dst_ptr[i] && src_ptr[i]) {
240 while (--i >= 0)
241 kfree(dst_ptr[i]);
242 return false;
243 }
244 }
245
246 return true;
247}
248
249static int property_entry_copy_data(struct property_entry *dst,
250 const struct property_entry *src)
251{
252 const void *pointer = property_get_pointer(src);
253 void *dst_ptr;
254 size_t nval;
255
256 /*
257 * Properties with no data should not be marked as stored
258 * out of line.
259 */
260 if (!src->is_inline && !src->length)
261 return -ENODATA;
262
263 /*
264 * Reference properties are never stored inline as
265 * they are too big.
266 */
267 if (src->type == DEV_PROP_REF && src->is_inline)
268 return -EINVAL;
269
270 if (src->length <= sizeof(dst->value)) {
271 dst_ptr = &dst->value;
272 dst->is_inline = true;
273 } else {
274 dst_ptr = kmalloc(src->length, GFP_KERNEL);
275 if (!dst_ptr)
276 return -ENOMEM;
277 dst->pointer = dst_ptr;
278 }
279
280 if (src->type == DEV_PROP_STRING) {
281 nval = src->length / sizeof(const char *);
282 if (!property_copy_string_array(dst_ptr, pointer, nval)) {
283 if (!dst->is_inline)
284 kfree(dst->pointer);
285 return -ENOMEM;
286 }
287 } else {
288 memcpy(dst_ptr, pointer, src->length);
289 }
290
291 dst->length = src->length;
292 dst->type = src->type;
293 dst->name = kstrdup(src->name, GFP_KERNEL);
294 if (!dst->name) {
295 property_entry_free_data(dst);
296 return -ENOMEM;
297 }
298
299 return 0;
300}
301
302/**
303 * property_entries_dup - duplicate array of properties
304 * @properties: array of properties to copy
305 *
306 * This function creates a deep copy of the given NULL-terminated array
307 * of property entries.
308 */
309struct property_entry *
310property_entries_dup(const struct property_entry *properties)
311{
312 struct property_entry *p;
313 int i, n = 0;
314 int ret;
315
316 if (!properties)
317 return NULL;
318
319 while (properties[n].name)
320 n++;
321
322 p = kcalloc(n + 1, sizeof(*p), GFP_KERNEL);
323 if (!p)
324 return ERR_PTR(-ENOMEM);
325
326 for (i = 0; i < n; i++) {
327 ret = property_entry_copy_data(&p[i], &properties[i]);
328 if (ret) {
329 while (--i >= 0)
330 property_entry_free_data(&p[i]);
331 kfree(p);
332 return ERR_PTR(ret);
333 }
334 }
335
336 return p;
337}
338EXPORT_SYMBOL_GPL(property_entries_dup);
339
340/**
341 * property_entries_free - free previously allocated array of properties
342 * @properties: array of properties to destroy
343 *
344 * This function frees given NULL-terminated array of property entries,
345 * along with their data.
346 */
347void property_entries_free(const struct property_entry *properties)
348{
349 const struct property_entry *p;
350
351 if (!properties)
352 return;
353
354 for (p = properties; p->name; p++)
355 property_entry_free_data(p);
356
357 kfree(properties);
358}
359EXPORT_SYMBOL_GPL(property_entries_free);
360
361/* -------------------------------------------------------------------------- */
362/* fwnode operations */
363
364static struct fwnode_handle *software_node_get(struct fwnode_handle *fwnode)
365{
366 struct swnode *swnode = to_swnode(fwnode);
367
368 kobject_get(&swnode->kobj);
369
370 return &swnode->fwnode;
371}
372
373static void software_node_put(struct fwnode_handle *fwnode)
374{
375 struct swnode *swnode = to_swnode(fwnode);
376
377 kobject_put(&swnode->kobj);
378}
379
380static bool software_node_property_present(const struct fwnode_handle *fwnode,
381 const char *propname)
382{
383 struct swnode *swnode = to_swnode(fwnode);
384
385 return !!property_entry_get(swnode->node->properties, propname);
386}
387
388static int software_node_read_int_array(const struct fwnode_handle *fwnode,
389 const char *propname,
390 unsigned int elem_size, void *val,
391 size_t nval)
392{
393 struct swnode *swnode = to_swnode(fwnode);
394
395 return property_entry_read_int_array(swnode->node->properties, propname,
396 elem_size, val, nval);
397}
398
399static int software_node_read_string_array(const struct fwnode_handle *fwnode,
400 const char *propname,
401 const char **val, size_t nval)
402{
403 struct swnode *swnode = to_swnode(fwnode);
404
405 return property_entry_read_string_array(swnode->node->properties,
406 propname, val, nval);
407}
408
409static const char *
410software_node_get_name(const struct fwnode_handle *fwnode)
411{
412 const struct swnode *swnode = to_swnode(fwnode);
413
414 if (!swnode)
415 return "(null)";
416
417 return kobject_name(&swnode->kobj);
418}
419
420static const char *
421software_node_get_name_prefix(const struct fwnode_handle *fwnode)
422{
423 struct fwnode_handle *parent;
424 const char *prefix;
425
426 parent = fwnode_get_parent(fwnode);
427 if (!parent)
428 return "";
429
430 /* Figure out the prefix from the parents. */
431 while (is_software_node(parent))
432 parent = fwnode_get_next_parent(parent);
433
434 prefix = fwnode_get_name_prefix(parent);
435 fwnode_handle_put(parent);
436
437 /* Guess something if prefix was NULL. */
438 return prefix ?: "/";
439}
440
441static struct fwnode_handle *
442software_node_get_parent(const struct fwnode_handle *fwnode)
443{
444 struct swnode *swnode = to_swnode(fwnode);
445
446 if (!swnode || !swnode->parent)
447 return NULL;
448
449 return fwnode_handle_get(&swnode->parent->fwnode);
450}
451
452static struct fwnode_handle *
453software_node_get_next_child(const struct fwnode_handle *fwnode,
454 struct fwnode_handle *child)
455{
456 struct swnode *p = to_swnode(fwnode);
457 struct swnode *c = to_swnode(child);
458
459 if (!p || list_empty(&p->children) ||
460 (c && list_is_last(&c->entry, &p->children))) {
461 fwnode_handle_put(child);
462 return NULL;
463 }
464
465 if (c)
466 c = list_next_entry(c, entry);
467 else
468 c = list_first_entry(&p->children, struct swnode, entry);
469
470 fwnode_handle_put(child);
471 return fwnode_handle_get(&c->fwnode);
472}
473
474static struct fwnode_handle *
475software_node_get_named_child_node(const struct fwnode_handle *fwnode,
476 const char *childname)
477{
478 struct swnode *swnode = to_swnode(fwnode);
479 struct swnode *child;
480
481 if (!swnode || list_empty(&swnode->children))
482 return NULL;
483
484 list_for_each_entry(child, &swnode->children, entry) {
485 if (!strcmp(childname, kobject_name(&child->kobj))) {
486 kobject_get(&child->kobj);
487 return &child->fwnode;
488 }
489 }
490 return NULL;
491}
492
493static int
494software_node_get_reference_args(const struct fwnode_handle *fwnode,
495 const char *propname, const char *nargs_prop,
496 unsigned int nargs, unsigned int index,
497 struct fwnode_reference_args *args)
498{
499 struct swnode *swnode = to_swnode(fwnode);
500 const struct software_node_ref_args *ref_array;
501 const struct software_node_ref_args *ref;
502 const struct property_entry *prop;
503 struct fwnode_handle *refnode;
504 u32 nargs_prop_val;
505 int error;
506 int i;
507
508 if (!swnode)
509 return -ENOENT;
510
511 prop = property_entry_get(swnode->node->properties, propname);
512 if (!prop)
513 return -ENOENT;
514
515 if (prop->type != DEV_PROP_REF)
516 return -EINVAL;
517
518 /*
519 * We expect that references are never stored inline, even
520 * single ones, as they are too big.
521 */
522 if (prop->is_inline)
523 return -EINVAL;
524
525 if (index * sizeof(*ref) >= prop->length)
526 return -ENOENT;
527
528 ref_array = prop->pointer;
529 ref = &ref_array[index];
530
531 refnode = software_node_fwnode(ref->node);
532 if (!refnode)
533 return -ENOENT;
534
535 if (nargs_prop) {
536 error = property_entry_read_int_array(swnode->node->properties,
537 nargs_prop, sizeof(u32),
538 &nargs_prop_val, 1);
539 if (error)
540 return error;
541
542 nargs = nargs_prop_val;
543 }
544
545 if (nargs > NR_FWNODE_REFERENCE_ARGS)
546 return -EINVAL;
547
548 args->fwnode = software_node_get(refnode);
549 args->nargs = nargs;
550
551 for (i = 0; i < nargs; i++)
552 args->args[i] = ref->args[i];
553
554 return 0;
555}
556
557static struct fwnode_handle *
558swnode_graph_find_next_port(const struct fwnode_handle *parent,
559 struct fwnode_handle *port)
560{
561 struct fwnode_handle *old = port;
562
563 while ((port = software_node_get_next_child(parent, old))) {
564 /*
565 * fwnode ports have naming style "port@", so we search for any
566 * children that follow that convention.
567 */
568 if (!strncmp(to_swnode(port)->node->name, "port@",
569 strlen("port@")))
570 return port;
571 old = port;
572 }
573
574 return NULL;
575}
576
577static struct fwnode_handle *
578software_node_graph_get_next_endpoint(const struct fwnode_handle *fwnode,
579 struct fwnode_handle *endpoint)
580{
581 struct swnode *swnode = to_swnode(fwnode);
582 struct fwnode_handle *parent;
583 struct fwnode_handle *port;
584
585 if (!swnode)
586 return NULL;
587
588 if (endpoint) {
589 port = software_node_get_parent(endpoint);
590 parent = software_node_get_parent(port);
591 } else {
592 parent = software_node_get_named_child_node(fwnode, "ports");
593 if (!parent)
594 parent = software_node_get(&swnode->fwnode);
595
596 port = swnode_graph_find_next_port(parent, NULL);
597 }
598
599 for (; port; port = swnode_graph_find_next_port(parent, port)) {
600 endpoint = software_node_get_next_child(port, endpoint);
601 if (endpoint) {
602 fwnode_handle_put(port);
603 break;
604 }
605 }
606
607 fwnode_handle_put(parent);
608
609 return endpoint;
610}
611
612static struct fwnode_handle *
613software_node_graph_get_remote_endpoint(const struct fwnode_handle *fwnode)
614{
615 struct swnode *swnode = to_swnode(fwnode);
616 const struct software_node_ref_args *ref;
617 const struct property_entry *prop;
618
619 if (!swnode)
620 return NULL;
621
622 prop = property_entry_get(swnode->node->properties, "remote-endpoint");
623 if (!prop || prop->type != DEV_PROP_REF || prop->is_inline)
624 return NULL;
625
626 ref = prop->pointer;
627
628 return software_node_get(software_node_fwnode(ref[0].node));
629}
630
631static struct fwnode_handle *
632software_node_graph_get_port_parent(struct fwnode_handle *fwnode)
633{
634 struct swnode *swnode = to_swnode(fwnode);
635
636 swnode = swnode->parent;
637 if (swnode && !strcmp(swnode->node->name, "ports"))
638 swnode = swnode->parent;
639
640 return swnode ? software_node_get(&swnode->fwnode) : NULL;
641}
642
643static int
644software_node_graph_parse_endpoint(const struct fwnode_handle *fwnode,
645 struct fwnode_endpoint *endpoint)
646{
647 struct swnode *swnode = to_swnode(fwnode);
648 const char *parent_name = swnode->parent->node->name;
649 int ret;
650
651 if (strlen("port@") >= strlen(parent_name) ||
652 strncmp(parent_name, "port@", strlen("port@")))
653 return -EINVAL;
654
655 /* Ports have naming style "port@n", we need to select the n */
656 ret = kstrtou32(parent_name + strlen("port@"), 10, &endpoint->port);
657 if (ret)
658 return ret;
659
660 endpoint->id = swnode->id;
661 endpoint->local_fwnode = fwnode;
662
663 return 0;
664}
665
666static const struct fwnode_operations software_node_ops = {
667 .get = software_node_get,
668 .put = software_node_put,
669 .property_present = software_node_property_present,
670 .property_read_int_array = software_node_read_int_array,
671 .property_read_string_array = software_node_read_string_array,
672 .get_name = software_node_get_name,
673 .get_name_prefix = software_node_get_name_prefix,
674 .get_parent = software_node_get_parent,
675 .get_next_child_node = software_node_get_next_child,
676 .get_named_child_node = software_node_get_named_child_node,
677 .get_reference_args = software_node_get_reference_args,
678 .graph_get_next_endpoint = software_node_graph_get_next_endpoint,
679 .graph_get_remote_endpoint = software_node_graph_get_remote_endpoint,
680 .graph_get_port_parent = software_node_graph_get_port_parent,
681 .graph_parse_endpoint = software_node_graph_parse_endpoint,
682};
683
684/* -------------------------------------------------------------------------- */
685
686/**
687 * software_node_find_by_name - Find software node by name
688 * @parent: Parent of the software node
689 * @name: Name of the software node
690 *
691 * The function will find a node that is child of @parent and that is named
692 * @name. If no node is found, the function returns NULL.
693 *
694 * NOTE: you will need to drop the reference with fwnode_handle_put() after use.
695 */
696const struct software_node *
697software_node_find_by_name(const struct software_node *parent, const char *name)
698{
699 struct swnode *swnode = NULL;
700 struct kobject *k;
701
702 if (!name)
703 return NULL;
704
705 spin_lock(&swnode_kset->list_lock);
706
707 list_for_each_entry(k, &swnode_kset->list, entry) {
708 swnode = kobj_to_swnode(k);
709 if (parent == swnode->node->parent && swnode->node->name &&
710 !strcmp(name, swnode->node->name)) {
711 kobject_get(&swnode->kobj);
712 break;
713 }
714 swnode = NULL;
715 }
716
717 spin_unlock(&swnode_kset->list_lock);
718
719 return swnode ? swnode->node : NULL;
720}
721EXPORT_SYMBOL_GPL(software_node_find_by_name);
722
723static struct software_node *software_node_alloc(const struct property_entry *properties)
724{
725 struct property_entry *props;
726 struct software_node *node;
727
728 props = property_entries_dup(properties);
729 if (IS_ERR(props))
730 return ERR_CAST(props);
731
732 node = kzalloc(sizeof(*node), GFP_KERNEL);
733 if (!node) {
734 property_entries_free(props);
735 return ERR_PTR(-ENOMEM);
736 }
737
738 node->properties = props;
739
740 return node;
741}
742
743static void software_node_free(const struct software_node *node)
744{
745 property_entries_free(node->properties);
746 kfree(node);
747}
748
749static void software_node_release(struct kobject *kobj)
750{
751 struct swnode *swnode = kobj_to_swnode(kobj);
752
753 if (swnode->parent) {
754 ida_simple_remove(&swnode->parent->child_ids, swnode->id);
755 list_del(&swnode->entry);
756 } else {
757 ida_simple_remove(&swnode_root_ids, swnode->id);
758 }
759
760 if (swnode->allocated)
761 software_node_free(swnode->node);
762
763 ida_destroy(&swnode->child_ids);
764 kfree(swnode);
765}
766
767static struct kobj_type software_node_type = {
768 .release = software_node_release,
769 .sysfs_ops = &kobj_sysfs_ops,
770};
771
772static struct fwnode_handle *
773swnode_register(const struct software_node *node, struct swnode *parent,
774 unsigned int allocated)
775{
776 struct swnode *swnode;
777 int ret;
778
779 swnode = kzalloc(sizeof(*swnode), GFP_KERNEL);
780 if (!swnode)
781 return ERR_PTR(-ENOMEM);
782
783 ret = ida_simple_get(parent ? &parent->child_ids : &swnode_root_ids,
784 0, 0, GFP_KERNEL);
785 if (ret < 0) {
786 kfree(swnode);
787 return ERR_PTR(ret);
788 }
789
790 swnode->id = ret;
791 swnode->node = node;
792 swnode->parent = parent;
793 swnode->kobj.kset = swnode_kset;
794 fwnode_init(&swnode->fwnode, &software_node_ops);
795
796 ida_init(&swnode->child_ids);
797 INIT_LIST_HEAD(&swnode->entry);
798 INIT_LIST_HEAD(&swnode->children);
799
800 if (node->name)
801 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
802 parent ? &parent->kobj : NULL,
803 "%s", node->name);
804 else
805 ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
806 parent ? &parent->kobj : NULL,
807 "node%d", swnode->id);
808 if (ret) {
809 kobject_put(&swnode->kobj);
810 return ERR_PTR(ret);
811 }
812
813 /*
814 * Assign the flag only in the successful case, so
815 * the above kobject_put() won't mess up with properties.
816 */
817 swnode->allocated = allocated;
818
819 if (parent)
820 list_add_tail(&swnode->entry, &parent->children);
821
822 kobject_uevent(&swnode->kobj, KOBJ_ADD);
823 return &swnode->fwnode;
824}
825
826/**
827 * software_node_register_nodes - Register an array of software nodes
828 * @nodes: Zero terminated array of software nodes to be registered
829 *
830 * Register multiple software nodes at once. If any node in the array
831 * has its .parent pointer set (which can only be to another software_node),
832 * then its parent **must** have been registered before it is; either outside
833 * of this function or by ordering the array such that parent comes before
834 * child.
835 */
836int software_node_register_nodes(const struct software_node *nodes)
837{
838 int ret;
839 int i;
840
841 for (i = 0; nodes[i].name; i++) {
842 const struct software_node *parent = nodes[i].parent;
843
844 if (parent && !software_node_to_swnode(parent)) {
845 ret = -EINVAL;
846 goto err_unregister_nodes;
847 }
848
849 ret = software_node_register(&nodes[i]);
850 if (ret)
851 goto err_unregister_nodes;
852 }
853
854 return 0;
855
856err_unregister_nodes:
857 software_node_unregister_nodes(nodes);
858 return ret;
859}
860EXPORT_SYMBOL_GPL(software_node_register_nodes);
861
862/**
863 * software_node_unregister_nodes - Unregister an array of software nodes
864 * @nodes: Zero terminated array of software nodes to be unregistered
865 *
866 * Unregister multiple software nodes at once. If parent pointers are set up
867 * in any of the software nodes then the array **must** be ordered such that
868 * parents come before their children.
869 *
870 * NOTE: If you are uncertain whether the array is ordered such that
871 * parents will be unregistered before their children, it is wiser to
872 * remove the nodes individually, in the correct order (child before
873 * parent).
874 */
875void software_node_unregister_nodes(const struct software_node *nodes)
876{
877 unsigned int i = 0;
878
879 while (nodes[i].name)
880 i++;
881
882 while (i--)
883 software_node_unregister(&nodes[i]);
884}
885EXPORT_SYMBOL_GPL(software_node_unregister_nodes);
886
887/**
888 * software_node_register_node_group - Register a group of software nodes
889 * @node_group: NULL terminated array of software node pointers to be registered
890 *
891 * Register multiple software nodes at once. If any node in the array
892 * has its .parent pointer set (which can only be to another software_node),
893 * then its parent **must** have been registered before it is; either outside
894 * of this function or by ordering the array such that parent comes before
895 * child.
896 */
897int software_node_register_node_group(const struct software_node **node_group)
898{
899 unsigned int i;
900 int ret;
901
902 if (!node_group)
903 return 0;
904
905 for (i = 0; node_group[i]; i++) {
906 ret = software_node_register(node_group[i]);
907 if (ret) {
908 software_node_unregister_node_group(node_group);
909 return ret;
910 }
911 }
912
913 return 0;
914}
915EXPORT_SYMBOL_GPL(software_node_register_node_group);
916
917/**
918 * software_node_unregister_node_group - Unregister a group of software nodes
919 * @node_group: NULL terminated array of software node pointers to be unregistered
920 *
921 * Unregister multiple software nodes at once. If parent pointers are set up
922 * in any of the software nodes then the array **must** be ordered such that
923 * parents come before their children.
924 *
925 * NOTE: If you are uncertain whether the array is ordered such that
926 * parents will be unregistered before their children, it is wiser to
927 * remove the nodes individually, in the correct order (child before
928 * parent).
929 */
930void software_node_unregister_node_group(
931 const struct software_node **node_group)
932{
933 unsigned int i = 0;
934
935 if (!node_group)
936 return;
937
938 while (node_group[i])
939 i++;
940
941 while (i--)
942 software_node_unregister(node_group[i]);
943}
944EXPORT_SYMBOL_GPL(software_node_unregister_node_group);
945
946/**
947 * software_node_register - Register static software node
948 * @node: The software node to be registered
949 */
950int software_node_register(const struct software_node *node)
951{
952 struct swnode *parent = software_node_to_swnode(node->parent);
953
954 if (software_node_to_swnode(node))
955 return -EEXIST;
956
957 if (node->parent && !parent)
958 return -EINVAL;
959
960 return PTR_ERR_OR_ZERO(swnode_register(node, parent, 0));
961}
962EXPORT_SYMBOL_GPL(software_node_register);
963
964/**
965 * software_node_unregister - Unregister static software node
966 * @node: The software node to be unregistered
967 */
968void software_node_unregister(const struct software_node *node)
969{
970 struct swnode *swnode;
971
972 swnode = software_node_to_swnode(node);
973 if (swnode)
974 fwnode_remove_software_node(&swnode->fwnode);
975}
976EXPORT_SYMBOL_GPL(software_node_unregister);
977
978struct fwnode_handle *
979fwnode_create_software_node(const struct property_entry *properties,
980 const struct fwnode_handle *parent)
981{
982 struct fwnode_handle *fwnode;
983 struct software_node *node;
984 struct swnode *p;
985
986 if (IS_ERR(parent))
987 return ERR_CAST(parent);
988
989 p = to_swnode(parent);
990 if (parent && !p)
991 return ERR_PTR(-EINVAL);
992
993 node = software_node_alloc(properties);
994 if (IS_ERR(node))
995 return ERR_CAST(node);
996
997 node->parent = p ? p->node : NULL;
998
999 fwnode = swnode_register(node, p, 1);
1000 if (IS_ERR(fwnode))
1001 software_node_free(node);
1002
1003 return fwnode;
1004}
1005EXPORT_SYMBOL_GPL(fwnode_create_software_node);
1006
1007void fwnode_remove_software_node(struct fwnode_handle *fwnode)
1008{
1009 struct swnode *swnode = to_swnode(fwnode);
1010
1011 if (!swnode)
1012 return;
1013
1014 kobject_put(&swnode->kobj);
1015}
1016EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
1017
1018/**
1019 * device_add_software_node - Assign software node to a device
1020 * @dev: The device the software node is meant for.
1021 * @node: The software node.
1022 *
1023 * This function will make @node the secondary firmware node pointer of @dev. If
1024 * @dev has no primary node, then @node will become the primary node. The
1025 * function will register @node automatically if it wasn't already registered.
1026 */
1027int device_add_software_node(struct device *dev, const struct software_node *node)
1028{
1029 struct swnode *swnode;
1030 int ret;
1031
1032 /* Only one software node per device. */
1033 if (dev_to_swnode(dev))
1034 return -EBUSY;
1035
1036 swnode = software_node_to_swnode(node);
1037 if (swnode) {
1038 kobject_get(&swnode->kobj);
1039 } else {
1040 ret = software_node_register(node);
1041 if (ret)
1042 return ret;
1043
1044 swnode = software_node_to_swnode(node);
1045 }
1046
1047 set_secondary_fwnode(dev, &swnode->fwnode);
1048
1049 /*
1050 * If the device has been fully registered by the time this function is
1051 * called, software_node_notify() must be called separately so that the
1052 * symlinks get created and the reference count of the node is kept in
1053 * balance.
1054 */
1055 if (device_is_registered(dev))
1056 software_node_notify(dev, KOBJ_ADD);
1057
1058 return 0;
1059}
1060EXPORT_SYMBOL_GPL(device_add_software_node);
1061
1062/**
1063 * device_remove_software_node - Remove device's software node
1064 * @dev: The device with the software node.
1065 *
1066 * This function will unregister the software node of @dev.
1067 */
1068void device_remove_software_node(struct device *dev)
1069{
1070 struct swnode *swnode;
1071
1072 swnode = dev_to_swnode(dev);
1073 if (!swnode)
1074 return;
1075
1076 if (device_is_registered(dev))
1077 software_node_notify(dev, KOBJ_REMOVE);
1078 set_secondary_fwnode(dev, NULL);
1079 kobject_put(&swnode->kobj);
1080}
1081EXPORT_SYMBOL_GPL(device_remove_software_node);
1082
1083/**
1084 * device_create_managed_software_node - Create a software node for a device
1085 * @dev: The device the software node is assigned to.
1086 * @properties: Device properties for the software node.
1087 * @parent: Parent of the software node.
1088 *
1089 * Creates a software node as a managed resource for @dev, which means the
1090 * lifetime of the newly created software node is tied to the lifetime of @dev.
1091 * Software nodes created with this function should not be reused or shared
1092 * because of that. The function takes a deep copy of @properties for the
1093 * software node.
1094 *
1095 * Since the new software node is assigned directly to @dev, and since it should
1096 * not be shared, it is not returned to the caller. The function returns 0 on
1097 * success, and errno in case of an error.
1098 */
1099int device_create_managed_software_node(struct device *dev,
1100 const struct property_entry *properties,
1101 const struct software_node *parent)
1102{
1103 struct fwnode_handle *p = software_node_fwnode(parent);
1104 struct fwnode_handle *fwnode;
1105
1106 if (parent && !p)
1107 return -EINVAL;
1108
1109 fwnode = fwnode_create_software_node(properties, p);
1110 if (IS_ERR(fwnode))
1111 return PTR_ERR(fwnode);
1112
1113 to_swnode(fwnode)->managed = true;
1114 set_secondary_fwnode(dev, fwnode);
1115
1116 if (device_is_registered(dev))
1117 software_node_notify(dev, KOBJ_ADD);
1118
1119 return 0;
1120}
1121EXPORT_SYMBOL_GPL(device_create_managed_software_node);
1122
1123int software_node_notify(struct device *dev, unsigned long action)
1124{
1125 struct swnode *swnode;
1126 int ret;
1127
1128 swnode = dev_to_swnode(dev);
1129 if (!swnode)
1130 return 0;
1131
1132 switch (action) {
1133 case KOBJ_ADD:
1134 ret = sysfs_create_link(&dev->kobj, &swnode->kobj, "software_node");
1135 if (ret)
1136 break;
1137
1138 ret = sysfs_create_link(&swnode->kobj, &dev->kobj,
1139 dev_name(dev));
1140 if (ret) {
1141 sysfs_remove_link(&dev->kobj, "software_node");
1142 break;
1143 }
1144 kobject_get(&swnode->kobj);
1145 break;
1146 case KOBJ_REMOVE:
1147 sysfs_remove_link(&swnode->kobj, dev_name(dev));
1148 sysfs_remove_link(&dev->kobj, "software_node");
1149 kobject_put(&swnode->kobj);
1150
1151 if (swnode->managed) {
1152 set_secondary_fwnode(dev, NULL);
1153 kobject_put(&swnode->kobj);
1154 }
1155 break;
1156 default:
1157 break;
1158 }
1159
1160 return 0;
1161}
1162
1163static int __init software_node_init(void)
1164{
1165 swnode_kset = kset_create_and_add("software_nodes", NULL, kernel_kobj);
1166 if (!swnode_kset)
1167 return -ENOMEM;
1168 return 0;
1169}
1170postcore_initcall(software_node_init);
1171
1172static void __exit software_node_exit(void)
1173{
1174 ida_destroy(&swnode_root_ids);
1175 kset_unregister(swnode_kset);
1176}
1177__exitcall(software_node_exit);