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