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 | |
27 | struct 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 | |
43 | static DEFINE_IDA(swnode_root_ids); |
44 | static struct kset *swnode_kset; |
45 | |
46 | #define kobj_to_swnode(_kobj_) container_of(_kobj_, struct swnode, kobj) |
47 | |
48 | static const struct fwnode_operations software_node_ops; |
49 | |
50 | bool is_software_node(const struct fwnode_handle *fwnode) |
51 | { |
52 | return !IS_ERR_OR_NULL(ptr: fwnode) && fwnode->ops == &software_node_ops; |
53 | } |
54 | EXPORT_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 | |
65 | static 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 | |
78 | static struct swnode * |
79 | software_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 | |
101 | const 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 | } |
107 | EXPORT_SYMBOL_GPL(to_software_node); |
108 | |
109 | struct 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 | } |
115 | EXPORT_SYMBOL_GPL(software_node_fwnode); |
116 | |
117 | /* -------------------------------------------------------------------------- */ |
118 | /* property_entry processing */ |
119 | |
120 | static const struct property_entry * |
121 | property_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 | |
133 | static 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 | |
141 | static 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 | |
158 | static int |
159 | property_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 | |
171 | static 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(val, pointer, length); |
193 | return 0; |
194 | } |
195 | |
196 | static 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(strings, pointer, length); |
222 | |
223 | return array_len; |
224 | } |
225 | |
226 | static 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 | |
244 | static 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 | |
262 | static 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(size: 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(dst_ptr, pointer, 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 | */ |
322 | struct property_entry * |
323 | property_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: n + 1, size: 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 | } |
351 | EXPORT_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 | */ |
360 | void 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 | } |
372 | EXPORT_SYMBOL_GPL(property_entries_free); |
373 | |
374 | /* -------------------------------------------------------------------------- */ |
375 | /* fwnode operations */ |
376 | |
377 | static 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 | |
386 | static 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 | |
393 | static 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 | |
401 | static 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 | |
412 | static 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 | |
422 | static const char * |
423 | software_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 | |
430 | static const char * |
431 | software_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 | |
451 | static struct fwnode_handle * |
452 | software_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 | |
462 | static struct fwnode_handle * |
463 | software_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 | |
484 | static struct fwnode_handle * |
485 | software_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 | |
503 | static int |
504 | software_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 * 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 | |
567 | static struct fwnode_handle * |
568 | swnode_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 | |
587 | static struct fwnode_handle * |
588 | software_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 | |
622 | static struct fwnode_handle * |
623 | software_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 | |
641 | static struct fwnode_handle * |
642 | software_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 | |
653 | static int |
654 | software_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 | |
676 | static 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_int_array = software_node_read_int_array, |
681 | .property_read_string_array = software_node_read_string_array, |
682 | .get_name = software_node_get_name, |
683 | .get_name_prefix = software_node_get_name_prefix, |
684 | .get_parent = software_node_get_parent, |
685 | .get_next_child_node = software_node_get_next_child, |
686 | .get_named_child_node = software_node_get_named_child_node, |
687 | .get_reference_args = software_node_get_reference_args, |
688 | .graph_get_next_endpoint = software_node_graph_get_next_endpoint, |
689 | .graph_get_remote_endpoint = software_node_graph_get_remote_endpoint, |
690 | .graph_get_port_parent = software_node_graph_get_port_parent, |
691 | .graph_parse_endpoint = software_node_graph_parse_endpoint, |
692 | }; |
693 | |
694 | /* -------------------------------------------------------------------------- */ |
695 | |
696 | /** |
697 | * software_node_find_by_name - Find software node by name |
698 | * @parent: Parent of the software node |
699 | * @name: Name of the software node |
700 | * |
701 | * The function will find a node that is child of @parent and that is named |
702 | * @name. If no node is found, the function returns NULL. |
703 | * |
704 | * NOTE: you will need to drop the reference with fwnode_handle_put() after use. |
705 | */ |
706 | const struct software_node * |
707 | software_node_find_by_name(const struct software_node *parent, const char *name) |
708 | { |
709 | struct swnode *swnode = NULL; |
710 | struct kobject *k; |
711 | |
712 | if (!name) |
713 | return NULL; |
714 | |
715 | spin_lock(lock: &swnode_kset->list_lock); |
716 | |
717 | list_for_each_entry(k, &swnode_kset->list, entry) { |
718 | swnode = kobj_to_swnode(k); |
719 | if (parent == swnode->node->parent && swnode->node->name && |
720 | !strcmp(name, swnode->node->name)) { |
721 | kobject_get(kobj: &swnode->kobj); |
722 | break; |
723 | } |
724 | swnode = NULL; |
725 | } |
726 | |
727 | spin_unlock(lock: &swnode_kset->list_lock); |
728 | |
729 | return swnode ? swnode->node : NULL; |
730 | } |
731 | EXPORT_SYMBOL_GPL(software_node_find_by_name); |
732 | |
733 | static struct software_node *software_node_alloc(const struct property_entry *properties) |
734 | { |
735 | struct property_entry *props; |
736 | struct software_node *node; |
737 | |
738 | props = property_entries_dup(properties); |
739 | if (IS_ERR(ptr: props)) |
740 | return ERR_CAST(ptr: props); |
741 | |
742 | node = kzalloc(size: sizeof(*node), GFP_KERNEL); |
743 | if (!node) { |
744 | property_entries_free(props); |
745 | return ERR_PTR(error: -ENOMEM); |
746 | } |
747 | |
748 | node->properties = props; |
749 | |
750 | return node; |
751 | } |
752 | |
753 | static void software_node_free(const struct software_node *node) |
754 | { |
755 | property_entries_free(node->properties); |
756 | kfree(objp: node); |
757 | } |
758 | |
759 | static void software_node_release(struct kobject *kobj) |
760 | { |
761 | struct swnode *swnode = kobj_to_swnode(kobj); |
762 | |
763 | if (swnode->parent) { |
764 | ida_free(&swnode->parent->child_ids, id: swnode->id); |
765 | list_del(entry: &swnode->entry); |
766 | } else { |
767 | ida_free(&swnode_root_ids, id: swnode->id); |
768 | } |
769 | |
770 | if (swnode->allocated) |
771 | software_node_free(node: swnode->node); |
772 | |
773 | ida_destroy(ida: &swnode->child_ids); |
774 | kfree(objp: swnode); |
775 | } |
776 | |
777 | static const struct kobj_type software_node_type = { |
778 | .release = software_node_release, |
779 | .sysfs_ops = &kobj_sysfs_ops, |
780 | }; |
781 | |
782 | static struct fwnode_handle * |
783 | swnode_register(const struct software_node *node, struct swnode *parent, |
784 | unsigned int allocated) |
785 | { |
786 | struct swnode *swnode; |
787 | int ret; |
788 | |
789 | swnode = kzalloc(size: sizeof(*swnode), GFP_KERNEL); |
790 | if (!swnode) |
791 | return ERR_PTR(error: -ENOMEM); |
792 | |
793 | ret = ida_alloc(ida: parent ? &parent->child_ids : &swnode_root_ids, |
794 | GFP_KERNEL); |
795 | if (ret < 0) { |
796 | kfree(objp: swnode); |
797 | return ERR_PTR(error: ret); |
798 | } |
799 | |
800 | swnode->id = ret; |
801 | swnode->node = node; |
802 | swnode->parent = parent; |
803 | swnode->kobj.kset = swnode_kset; |
804 | fwnode_init(fwnode: &swnode->fwnode, ops: &software_node_ops); |
805 | |
806 | ida_init(ida: &swnode->child_ids); |
807 | INIT_LIST_HEAD(list: &swnode->entry); |
808 | INIT_LIST_HEAD(list: &swnode->children); |
809 | |
810 | if (node->name) |
811 | ret = kobject_init_and_add(kobj: &swnode->kobj, ktype: &software_node_type, |
812 | parent: parent ? &parent->kobj : NULL, |
813 | fmt: "%s" , node->name); |
814 | else |
815 | ret = kobject_init_and_add(kobj: &swnode->kobj, ktype: &software_node_type, |
816 | parent: parent ? &parent->kobj : NULL, |
817 | fmt: "node%d" , swnode->id); |
818 | if (ret) { |
819 | kobject_put(kobj: &swnode->kobj); |
820 | return ERR_PTR(error: ret); |
821 | } |
822 | |
823 | /* |
824 | * Assign the flag only in the successful case, so |
825 | * the above kobject_put() won't mess up with properties. |
826 | */ |
827 | swnode->allocated = allocated; |
828 | |
829 | if (parent) |
830 | list_add_tail(new: &swnode->entry, head: &parent->children); |
831 | |
832 | kobject_uevent(kobj: &swnode->kobj, action: KOBJ_ADD); |
833 | return &swnode->fwnode; |
834 | } |
835 | |
836 | /** |
837 | * software_node_register_node_group - Register a group of software nodes |
838 | * @node_group: NULL terminated array of software node pointers to be registered |
839 | * |
840 | * Register multiple software nodes at once. If any node in the array |
841 | * has its .parent pointer set (which can only be to another software_node), |
842 | * then its parent **must** have been registered before it is; either outside |
843 | * of this function or by ordering the array such that parent comes before |
844 | * child. |
845 | */ |
846 | int software_node_register_node_group(const struct software_node **node_group) |
847 | { |
848 | unsigned int i; |
849 | int ret; |
850 | |
851 | if (!node_group) |
852 | return 0; |
853 | |
854 | for (i = 0; node_group[i]; i++) { |
855 | ret = software_node_register(node: node_group[i]); |
856 | if (ret) { |
857 | software_node_unregister_node_group(node_group); |
858 | return ret; |
859 | } |
860 | } |
861 | |
862 | return 0; |
863 | } |
864 | EXPORT_SYMBOL_GPL(software_node_register_node_group); |
865 | |
866 | /** |
867 | * software_node_unregister_node_group - Unregister a group of software nodes |
868 | * @node_group: NULL terminated array of software node pointers to be unregistered |
869 | * |
870 | * Unregister multiple software nodes at once. If parent pointers are set up |
871 | * in any of the software nodes then the array **must** be ordered such that |
872 | * parents come before their children. |
873 | * |
874 | * NOTE: If you are uncertain whether the array is ordered such that |
875 | * parents will be unregistered before their children, it is wiser to |
876 | * remove the nodes individually, in the correct order (child before |
877 | * parent). |
878 | */ |
879 | void software_node_unregister_node_group( |
880 | const struct software_node **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 | } |
893 | EXPORT_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 | */ |
899 | int 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 | } |
911 | EXPORT_SYMBOL_GPL(software_node_register); |
912 | |
913 | /** |
914 | * software_node_unregister - Unregister static software node |
915 | * @node: The software node to be unregistered |
916 | */ |
917 | void 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 | } |
925 | EXPORT_SYMBOL_GPL(software_node_unregister); |
926 | |
927 | struct fwnode_handle * |
928 | fwnode_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 | } |
954 | EXPORT_SYMBOL_GPL(fwnode_create_software_node); |
955 | |
956 | void 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 | } |
965 | EXPORT_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 | */ |
976 | int 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 | } |
1009 | EXPORT_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 | */ |
1017 | void 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 | } |
1031 | EXPORT_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 | */ |
1049 | int 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 | } |
1071 | EXPORT_SYMBOL_GPL(device_create_managed_software_node); |
1072 | |
1073 | void 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 | ret = sysfs_create_link(kobj: &dev->kobj, target: &swnode->kobj, name: "software_node" ); |
1083 | if (ret) |
1084 | return; |
1085 | |
1086 | ret = sysfs_create_link(kobj: &swnode->kobj, target: &dev->kobj, name: dev_name(dev)); |
1087 | if (ret) { |
1088 | sysfs_remove_link(kobj: &dev->kobj, name: "software_node" ); |
1089 | return; |
1090 | } |
1091 | |
1092 | kobject_get(kobj: &swnode->kobj); |
1093 | } |
1094 | |
1095 | void software_node_notify_remove(struct device *dev) |
1096 | { |
1097 | struct swnode *swnode; |
1098 | |
1099 | swnode = dev_to_swnode(dev); |
1100 | if (!swnode) |
1101 | return; |
1102 | |
1103 | sysfs_remove_link(kobj: &swnode->kobj, name: dev_name(dev)); |
1104 | sysfs_remove_link(kobj: &dev->kobj, name: "software_node" ); |
1105 | kobject_put(kobj: &swnode->kobj); |
1106 | |
1107 | if (swnode->managed) { |
1108 | set_secondary_fwnode(dev, NULL); |
1109 | kobject_put(kobj: &swnode->kobj); |
1110 | } |
1111 | } |
1112 | |
1113 | static int __init software_node_init(void) |
1114 | { |
1115 | swnode_kset = kset_create_and_add(name: "software_nodes" , NULL, parent_kobj: kernel_kobj); |
1116 | if (!swnode_kset) |
1117 | return -ENOMEM; |
1118 | return 0; |
1119 | } |
1120 | postcore_initcall(software_node_init); |
1121 | |
1122 | static void __exit software_node_exit(void) |
1123 | { |
1124 | ida_destroy(ida: &swnode_root_ids); |
1125 | kset_unregister(kset: swnode_kset); |
1126 | } |
1127 | __exitcall(software_node_exit); |
1128 | |