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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ACPI device specific properties support.
4 *
5 * Copyright (C) 2014 - 2023, Intel Corporation
6 * All rights reserved.
7 *
8 * Authors: Mika Westerberg <[email protected]>
9 * Darren Hart <[email protected]>
10 * Rafael J. Wysocki <[email protected]>
11 * Sakari Ailus <[email protected]>
12 */
13
14#define pr_fmt(fmt) "ACPI: " fmt
15
16#include <linux/acpi.h>
17#include <linux/device.h>
18#include <linux/export.h>
19
20#include "internal.h"
21
22static int acpi_data_get_property_array(const struct acpi_device_data *data,
23 const char *name,
24 acpi_object_type type,
25 const union acpi_object **obj);
26
27/*
28 * The GUIDs here are made equivalent to each other in order to avoid extra
29 * complexity in the properties handling code, with the caveat that the
30 * kernel will accept certain combinations of GUID and properties that are
31 * not defined without a warning. For instance if any of the properties
32 * from different GUID appear in a property list of another, it will be
33 * accepted by the kernel. Firmware validation tools should catch these.
34 *
35 * References:
36 *
37 * [1] UEFI DSD Guide.
38 * https://github.com/UEFI/DSD-Guide/blob/main/src/dsd-guide.adoc
39 */
40static const guid_t prp_guids[] = {
41 /* ACPI _DSD device properties GUID [1]: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
42 GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c,
43 0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01),
44 /* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */
45 GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3,
46 0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4),
47 /* External facing port GUID: efcc06cc-73ac-4bc3-bff0-76143807c389 */
48 GUID_INIT(0xefcc06cc, 0x73ac, 0x4bc3,
49 0xbf, 0xf0, 0x76, 0x14, 0x38, 0x07, 0xc3, 0x89),
50 /* Thunderbolt GUID for IMR_VALID: c44d002f-69f9-4e7d-a904-a7baabdf43f7 */
51 GUID_INIT(0xc44d002f, 0x69f9, 0x4e7d,
52 0xa9, 0x04, 0xa7, 0xba, 0xab, 0xdf, 0x43, 0xf7),
53 /* Thunderbolt GUID for WAKE_SUPPORTED: 6c501103-c189-4296-ba72-9bf5a26ebe5d */
54 GUID_INIT(0x6c501103, 0xc189, 0x4296,
55 0xba, 0x72, 0x9b, 0xf5, 0xa2, 0x6e, 0xbe, 0x5d),
56 /* Storage device needs D3 GUID: 5025030f-842f-4ab4-a561-99a5189762d0 */
57 GUID_INIT(0x5025030f, 0x842f, 0x4ab4,
58 0xa5, 0x61, 0x99, 0xa5, 0x18, 0x97, 0x62, 0xd0),
59};
60
61/* ACPI _DSD data subnodes GUID [1]: dbb8e3e6-5886-4ba6-8795-1319f52a966b */
62static const guid_t ads_guid =
63 GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
64 0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b);
65
66/* ACPI _DSD data buffer GUID [1]: edb12dd0-363d-4085-a3d2-49522ca160c4 */
67static const guid_t buffer_prop_guid =
68 GUID_INIT(0xedb12dd0, 0x363d, 0x4085,
69 0xa3, 0xd2, 0x49, 0x52, 0x2c, 0xa1, 0x60, 0xc4);
70
71static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
72 union acpi_object *desc,
73 struct acpi_device_data *data,
74 struct fwnode_handle *parent);
75static bool acpi_extract_properties(acpi_handle handle,
76 union acpi_object *desc,
77 struct acpi_device_data *data);
78
79static bool acpi_nondev_subnode_extract(union acpi_object *desc,
80 acpi_handle handle,
81 const union acpi_object *link,
82 struct list_head *list,
83 struct fwnode_handle *parent)
84{
85 struct acpi_data_node *dn;
86 acpi_handle scope = NULL;
87 bool result;
88
89 if (acpi_graph_ignore_port(handle))
90 return false;
91
92 dn = kzalloc_obj(*dn);
93 if (!dn)
94 return false;
95
96 dn->name = link->package.elements[0].string.pointer;
97 fwnode_init(&dn->fwnode, &acpi_data_fwnode_ops);
98 dn->parent = parent;
99 INIT_LIST_HEAD(&dn->data.properties);
100 INIT_LIST_HEAD(&dn->data.subnodes);
101
102 /*
103 * The scope for the completion of relative pathname segments and
104 * subnode object lookup is the one of the namespace node (device)
105 * containing the object that has returned the package. That is, it's
106 * the scope of that object's parent device.
107 */
108 if (handle)
109 acpi_get_parent(handle, &scope);
110
111 /*
112 * Extract properties from the _DSD-equivalent package pointed to by
113 * desc and use scope (if not NULL) for the completion of relative
114 * pathname segments.
115 *
116 * The extracted properties will be held in the new data node dn.
117 */
118 result = acpi_extract_properties(scope, desc, &dn->data);
119 /*
120 * Look for subnodes in the _DSD-equivalent package pointed to by desc
121 * and create child nodes of dn if there are any.
122 */
123 if (acpi_enumerate_nondev_subnodes(scope, desc, &dn->data, &dn->fwnode))
124 result = true;
125
126 if (!result) {
127 kfree(dn);
128 acpi_handle_debug(handle, "Invalid properties/subnodes data, skipping\n");
129 return false;
130 }
131
132 /*
133 * This will be NULL if the desc package is embedded in an outer
134 * _DSD-equivalent package and its scope cannot be determined.
135 */
136 dn->handle = handle;
137 dn->data.pointer = desc;
138 list_add_tail(&dn->sibling, list);
139
140 return true;
141}
142
143static bool acpi_nondev_subnode_ok(acpi_handle scope,
144 const union acpi_object *link,
145 struct list_head *list,
146 struct fwnode_handle *parent)
147{
148 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
149 acpi_handle handle;
150 acpi_status status;
151
152 /*
153 * If the scope is unknown, the _DSD-equivalent package being parsed
154 * was embedded in an outer _DSD-equivalent package as a result of
155 * direct evaluation of an object pointed to by a reference. In that
156 * case, using a pathname as the target object pointer is invalid.
157 */
158 if (!scope)
159 return false;
160
161 status = acpi_get_handle(scope, link->package.elements[1].string.pointer,
162 &handle);
163 if (ACPI_FAILURE(status))
164 return false;
165
166 status = acpi_evaluate_object_typed(handle, NULL, NULL, &buf,
167 ACPI_TYPE_PACKAGE);
168 if (ACPI_FAILURE(status))
169 return false;
170
171 if (acpi_nondev_subnode_extract(buf.pointer, handle, link, list,
172 parent))
173 return true;
174
175 ACPI_FREE(buf.pointer);
176 return false;
177}
178
179static bool acpi_add_nondev_subnodes(acpi_handle scope,
180 union acpi_object *links,
181 struct list_head *list,
182 struct fwnode_handle *parent)
183{
184 bool ret = false;
185 int i;
186
187 /*
188 * Every element in the links package is expected to represent a link
189 * to a non-device node in a tree containing device-specific data.
190 */
191 for (i = 0; i < links->package.count; i++) {
192 union acpi_object *link, *desc;
193 bool result;
194
195 link = &links->package.elements[i];
196 /* Only two elements allowed. */
197 if (link->package.count != 2)
198 continue;
199
200 /* The first one (the key) must be a string. */
201 if (link->package.elements[0].type != ACPI_TYPE_STRING)
202 continue;
203
204 /* The second one (the target) may be a string or a package. */
205 switch (link->package.elements[1].type) {
206 case ACPI_TYPE_STRING:
207 /*
208 * The string is expected to be a full pathname or a
209 * pathname segment relative to the given scope. That
210 * pathname is expected to point to an object returning
211 * a package that contains _DSD-equivalent information.
212 */
213 result = acpi_nondev_subnode_ok(scope, link, list,
214 parent);
215 break;
216 case ACPI_TYPE_PACKAGE:
217 /*
218 * This happens when a reference is used in AML to
219 * point to the target. Since the target is expected
220 * to be a named object, a reference to it will cause it
221 * to be avaluated in place and its return package will
222 * be embedded in the links package at the location of
223 * the reference.
224 *
225 * The target package is expected to contain _DSD-
226 * equivalent information, but the scope in which it
227 * is located in the original AML is unknown. Thus
228 * it cannot contain pathname segments represented as
229 * strings because there is no way to build full
230 * pathnames out of them.
231 */
232 acpi_handle_debug(scope, "subnode %s: Unknown scope\n",
233 link->package.elements[0].string.pointer);
234 desc = &link->package.elements[1];
235 result = acpi_nondev_subnode_extract(desc, NULL, link,
236 list, parent);
237 break;
238 case ACPI_TYPE_LOCAL_REFERENCE:
239 /*
240 * It is not expected to see any local references in
241 * the links package because referencing a named object
242 * should cause it to be evaluated in place.
243 */
244 acpi_handle_info(scope, "subnode %s: Unexpected reference\n",
245 link->package.elements[0].string.pointer);
246 fallthrough;
247 default:
248 result = false;
249 break;
250 }
251 ret = ret || result;
252 }
253
254 return ret;
255}
256
257static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
258 union acpi_object *desc,
259 struct acpi_device_data *data,
260 struct fwnode_handle *parent)
261{
262 int i;
263
264 /* Look for the ACPI data subnodes GUID. */
265 for (i = 0; i < desc->package.count; i += 2) {
266 const union acpi_object *guid;
267 union acpi_object *links;
268
269 guid = &desc->package.elements[i];
270 links = &desc->package.elements[i + 1];
271
272 /*
273 * The first element must be a GUID and the second one must be
274 * a package.
275 */
276 if (guid->type != ACPI_TYPE_BUFFER ||
277 guid->buffer.length != 16 ||
278 links->type != ACPI_TYPE_PACKAGE)
279 break;
280
281 if (!guid_equal((guid_t *)guid->buffer.pointer, &ads_guid))
282 continue;
283
284 return acpi_add_nondev_subnodes(scope, links, &data->subnodes,
285 parent);
286 }
287
288 return false;
289}
290
291static bool acpi_property_value_ok(const union acpi_object *value)
292{
293 int j;
294
295 /*
296 * The value must be an integer, a string, a reference, or a package
297 * whose every element must be an integer, a string, or a reference.
298 */
299 switch (value->type) {
300 case ACPI_TYPE_INTEGER:
301 case ACPI_TYPE_STRING:
302 case ACPI_TYPE_LOCAL_REFERENCE:
303 return true;
304
305 case ACPI_TYPE_PACKAGE:
306 for (j = 0; j < value->package.count; j++)
307 switch (value->package.elements[j].type) {
308 case ACPI_TYPE_INTEGER:
309 case ACPI_TYPE_STRING:
310 case ACPI_TYPE_LOCAL_REFERENCE:
311 continue;
312
313 default:
314 return false;
315 }
316
317 return true;
318 }
319 return false;
320}
321
322static bool acpi_properties_format_valid(const union acpi_object *properties)
323{
324 int i;
325
326 for (i = 0; i < properties->package.count; i++) {
327 const union acpi_object *property;
328
329 property = &properties->package.elements[i];
330 /*
331 * Only two elements allowed, the first one must be a string and
332 * the second one has to satisfy certain conditions.
333 */
334 if (property->package.count != 2
335 || property->package.elements[0].type != ACPI_TYPE_STRING
336 || !acpi_property_value_ok(&property->package.elements[1]))
337 return false;
338 }
339 return true;
340}
341
342static void acpi_init_of_compatible(struct acpi_device *adev)
343{
344 const union acpi_object *of_compatible;
345 int ret;
346
347 ret = acpi_data_get_property_array(&adev->data, "compatible",
348 ACPI_TYPE_STRING, &of_compatible);
349 if (ret) {
350 ret = acpi_dev_get_property(adev, "compatible",
351 ACPI_TYPE_STRING, &of_compatible);
352 if (ret) {
353 struct acpi_device *parent;
354
355 parent = acpi_dev_parent(adev);
356 if (parent && parent->flags.of_compatible_ok)
357 goto out;
358
359 return;
360 }
361 }
362 adev->data.of_compatible = of_compatible;
363
364 out:
365 adev->flags.of_compatible_ok = 1;
366}
367
368static bool acpi_is_property_guid(const guid_t *guid)
369{
370 int i;
371
372 for (i = 0; i < ARRAY_SIZE(prp_guids); i++) {
373 if (guid_equal(guid, &prp_guids[i]))
374 return true;
375 }
376
377 return false;
378}
379
380struct acpi_device_properties *
381acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
382 union acpi_object *properties)
383{
384 struct acpi_device_properties *props;
385
386 props = kzalloc_obj(*props);
387 if (props) {
388 INIT_LIST_HEAD(&props->list);
389 props->guid = guid;
390 props->properties = properties;
391 list_add_tail(&props->list, &data->properties);
392 }
393
394 return props;
395}
396
397static void acpi_nondev_subnode_tag(acpi_handle handle, void *context)
398{
399}
400
401static void acpi_untie_nondev_subnodes(struct acpi_device_data *data)
402{
403 struct acpi_data_node *dn;
404
405 list_for_each_entry(dn, &data->subnodes, sibling) {
406 if (!dn->handle)
407 continue;
408
409 acpi_detach_data(dn->handle, acpi_nondev_subnode_tag);
410
411 acpi_untie_nondev_subnodes(&dn->data);
412 }
413}
414
415static bool acpi_tie_nondev_subnodes(struct acpi_device_data *data)
416{
417 struct acpi_data_node *dn;
418
419 list_for_each_entry(dn, &data->subnodes, sibling) {
420 acpi_status status;
421 bool ret;
422
423 if (!dn->handle)
424 continue;
425
426 status = acpi_attach_data(dn->handle, acpi_nondev_subnode_tag, dn);
427 if (ACPI_FAILURE(status) && status != AE_ALREADY_EXISTS) {
428 acpi_handle_err(dn->handle, "Can't tag data node\n");
429 return false;
430 }
431
432 ret = acpi_tie_nondev_subnodes(&dn->data);
433 if (!ret)
434 return ret;
435 }
436
437 return true;
438}
439
440static void acpi_data_add_buffer_props(acpi_handle handle,
441 struct acpi_device_data *data,
442 union acpi_object *properties)
443{
444 struct acpi_device_properties *props;
445 union acpi_object *package;
446 size_t alloc_size;
447 unsigned int i;
448 u32 *count;
449
450 if (check_mul_overflow((size_t)properties->package.count,
451 sizeof(*package) + sizeof(void *),
452 &alloc_size) ||
453 check_add_overflow(sizeof(*props) + sizeof(*package), alloc_size,
454 &alloc_size)) {
455 acpi_handle_warn(handle,
456 "can't allocate memory for %u buffer props",
457 properties->package.count);
458 return;
459 }
460
461 props = kvzalloc(alloc_size, GFP_KERNEL);
462 if (!props)
463 return;
464
465 props->guid = &buffer_prop_guid;
466 props->bufs = (void *)(props + 1);
467 props->properties = (void *)(props->bufs + properties->package.count);
468
469 /* Outer package */
470 package = props->properties;
471 package->type = ACPI_TYPE_PACKAGE;
472 package->package.elements = package + 1;
473 count = &package->package.count;
474 *count = 0;
475
476 /* Inner packages */
477 package++;
478
479 for (i = 0; i < properties->package.count; i++) {
480 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
481 union acpi_object *property = &properties->package.elements[i];
482 union acpi_object *prop, *obj, *buf_obj;
483 acpi_status status;
484
485 if (property->type != ACPI_TYPE_PACKAGE ||
486 property->package.count != 2) {
487 acpi_handle_warn(handle,
488 "buffer property %u has %u entries\n",
489 i, property->package.count);
490 continue;
491 }
492
493 prop = &property->package.elements[0];
494 obj = &property->package.elements[1];
495
496 if (prop->type != ACPI_TYPE_STRING ||
497 obj->type != ACPI_TYPE_STRING) {
498 acpi_handle_warn(handle,
499 "wrong object types %u and %u\n",
500 prop->type, obj->type);
501 continue;
502 }
503
504 status = acpi_evaluate_object_typed(handle, obj->string.pointer,
505 NULL, &buf,
506 ACPI_TYPE_BUFFER);
507 if (ACPI_FAILURE(status)) {
508 acpi_handle_warn(handle,
509 "can't evaluate \"%*pE\" as buffer\n",
510 obj->string.length,
511 obj->string.pointer);
512 continue;
513 }
514
515 package->type = ACPI_TYPE_PACKAGE;
516 package->package.elements = prop;
517 package->package.count = 2;
518
519 buf_obj = buf.pointer;
520
521 /* Replace the string object with a buffer object */
522 obj->type = ACPI_TYPE_BUFFER;
523 obj->buffer.length = buf_obj->buffer.length;
524 obj->buffer.pointer = buf_obj->buffer.pointer;
525
526 props->bufs[i] = buf.pointer;
527 package++;
528 (*count)++;
529 }
530
531 if (*count)
532 list_add(&props->list, &data->properties);
533 else
534 kvfree(props);
535}
536
537static bool acpi_extract_properties(acpi_handle scope, union acpi_object *desc,
538 struct acpi_device_data *data)
539{
540 int i;
541
542 if (desc->package.count % 2)
543 return false;
544
545 /* Look for the device properties GUID. */
546 for (i = 0; i < desc->package.count; i += 2) {
547 const union acpi_object *guid;
548 union acpi_object *properties;
549
550 guid = &desc->package.elements[i];
551 properties = &desc->package.elements[i + 1];
552
553 /*
554 * The first element must be a GUID and the second one must be
555 * a package.
556 */
557 if (guid->type != ACPI_TYPE_BUFFER ||
558 guid->buffer.length != 16 ||
559 properties->type != ACPI_TYPE_PACKAGE)
560 break;
561
562 if (guid_equal((guid_t *)guid->buffer.pointer,
563 &buffer_prop_guid)) {
564 acpi_data_add_buffer_props(scope, data, properties);
565 continue;
566 }
567
568 if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
569 continue;
570
571 /*
572 * We found the matching GUID. Now validate the format of the
573 * package immediately following it.
574 */
575 if (!acpi_properties_format_valid(properties))
576 continue;
577
578 acpi_data_add_props(data, (const guid_t *)guid->buffer.pointer,
579 properties);
580 }
581
582 return !list_empty(&data->properties);
583}
584
585void acpi_init_properties(struct acpi_device *adev)
586{
587 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
588 struct acpi_hardware_id *hwid;
589 acpi_status status;
590 bool acpi_of = false;
591
592 INIT_LIST_HEAD(&adev->data.properties);
593 INIT_LIST_HEAD(&adev->data.subnodes);
594
595 if (!adev->handle)
596 return;
597
598 /*
599 * Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
600 * Device Tree compatible properties for this device.
601 */
602 list_for_each_entry(hwid, &adev->pnp.ids, list) {
603 if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
604 acpi_of = true;
605 break;
606 }
607 }
608
609 status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
610 ACPI_TYPE_PACKAGE);
611 if (ACPI_FAILURE(status))
612 goto out;
613
614 if (acpi_extract_properties(adev->handle, buf.pointer, &adev->data)) {
615 adev->data.pointer = buf.pointer;
616 if (acpi_of)
617 acpi_init_of_compatible(adev);
618 }
619 if (acpi_enumerate_nondev_subnodes(adev->handle, buf.pointer,
620 &adev->data, acpi_fwnode_handle(adev)))
621 adev->data.pointer = buf.pointer;
622
623 if (!adev->data.pointer) {
624 acpi_handle_debug(adev->handle, "Invalid _DSD data, skipping\n");
625 ACPI_FREE(buf.pointer);
626 } else {
627 if (!acpi_tie_nondev_subnodes(&adev->data))
628 acpi_untie_nondev_subnodes(&adev->data);
629 }
630
631 out:
632 if (acpi_of && !adev->flags.of_compatible_ok)
633 acpi_handle_info(adev->handle,
634 ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n");
635
636 if (!adev->data.pointer)
637 acpi_extract_apple_properties(adev);
638}
639
640static void acpi_free_device_properties(struct list_head *list)
641{
642 struct acpi_device_properties *props, *tmp;
643
644 list_for_each_entry_safe(props, tmp, list, list) {
645 u32 i;
646
647 list_del(&props->list);
648 /* Buffer data properties were separately allocated */
649 if (props->bufs)
650 for (i = 0; i < props->properties->package.count; i++)
651 ACPI_FREE(props->bufs[i]);
652 kvfree(props);
653 }
654}
655
656static void acpi_destroy_nondev_subnodes(struct list_head *list)
657{
658 struct acpi_data_node *dn, *next;
659
660 if (list_empty(list))
661 return;
662
663 list_for_each_entry_safe_reverse(dn, next, list, sibling) {
664 acpi_destroy_nondev_subnodes(&dn->data.subnodes);
665 wait_for_completion(&dn->kobj_done);
666 list_del(&dn->sibling);
667 ACPI_FREE((void *)dn->data.pointer);
668 acpi_free_device_properties(&dn->data.properties);
669 kfree(dn);
670 }
671}
672
673void acpi_free_properties(struct acpi_device *adev)
674{
675 acpi_untie_nondev_subnodes(&adev->data);
676 acpi_destroy_nondev_subnodes(&adev->data.subnodes);
677 ACPI_FREE((void *)adev->data.pointer);
678 adev->data.of_compatible = NULL;
679 adev->data.pointer = NULL;
680 acpi_free_device_properties(&adev->data.properties);
681}
682
683/**
684 * acpi_data_get_property - return an ACPI property with given name
685 * @data: ACPI device deta object to get the property from
686 * @name: Name of the property
687 * @type: Expected property type
688 * @obj: Location to store the property value (if not %NULL)
689 *
690 * Look up a property with @name and store a pointer to the resulting ACPI
691 * object at the location pointed to by @obj if found.
692 *
693 * Callers must not attempt to free the returned objects. These objects will be
694 * freed by the ACPI core automatically during the removal of @data.
695 *
696 * Return: %0 if property with @name has been found (success),
697 * %-EINVAL if the arguments are invalid,
698 * %-EINVAL if the property doesn't exist,
699 * %-EPROTO if the property value type doesn't match @type.
700 */
701static int acpi_data_get_property(const struct acpi_device_data *data,
702 const char *name, acpi_object_type type,
703 const union acpi_object **obj)
704{
705 const struct acpi_device_properties *props;
706
707 if (!data || !name)
708 return -EINVAL;
709
710 if (!data->pointer || list_empty(&data->properties))
711 return -EINVAL;
712
713 list_for_each_entry(props, &data->properties, list) {
714 const union acpi_object *properties;
715 unsigned int i;
716
717 properties = props->properties;
718 for (i = 0; i < properties->package.count; i++) {
719 const union acpi_object *propname, *propvalue;
720 const union acpi_object *property;
721
722 property = &properties->package.elements[i];
723
724 propname = &property->package.elements[0];
725 propvalue = &property->package.elements[1];
726
727 if (!strcmp(name, propname->string.pointer)) {
728 if (type != ACPI_TYPE_ANY &&
729 propvalue->type != type)
730 return -EPROTO;
731 if (obj)
732 *obj = propvalue;
733
734 return 0;
735 }
736 }
737 }
738 return -EINVAL;
739}
740
741/**
742 * acpi_dev_get_property - return an ACPI property with given name.
743 * @adev: ACPI device to get the property from.
744 * @name: Name of the property.
745 * @type: Expected property type.
746 * @obj: Location to store the property value (if not %NULL).
747 */
748int acpi_dev_get_property(const struct acpi_device *adev, const char *name,
749 acpi_object_type type, const union acpi_object **obj)
750{
751 return adev ? acpi_data_get_property(&adev->data, name, type, obj) : -EINVAL;
752}
753EXPORT_SYMBOL_GPL(acpi_dev_get_property);
754
755static const struct acpi_device_data *
756acpi_device_data_of_node(const struct fwnode_handle *fwnode)
757{
758 if (is_acpi_device_node(fwnode)) {
759 const struct acpi_device *adev = to_acpi_device_node(fwnode);
760 return &adev->data;
761 }
762 if (is_acpi_data_node(fwnode)) {
763 const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
764 return &dn->data;
765 }
766 return NULL;
767}
768
769/**
770 * acpi_node_prop_get - return an ACPI property with given name.
771 * @fwnode: Firmware node to get the property from.
772 * @propname: Name of the property.
773 * @valptr: Location to store a pointer to the property value (if not %NULL).
774 */
775int acpi_node_prop_get(const struct fwnode_handle *fwnode,
776 const char *propname, void **valptr)
777{
778 return acpi_data_get_property(acpi_device_data_of_node(fwnode),
779 propname, ACPI_TYPE_ANY,
780 (const union acpi_object **)valptr);
781}
782
783/**
784 * acpi_data_get_property_array - return an ACPI array property with given name
785 * @data: ACPI data object to get the property from
786 * @name: Name of the property
787 * @type: Expected type of array elements
788 * @obj: Location to store a pointer to the property value (if not NULL)
789 *
790 * Look up an array property with @name and store a pointer to the resulting
791 * ACPI object at the location pointed to by @obj if found.
792 *
793 * Callers must not attempt to free the returned objects. Those objects will be
794 * freed by the ACPI core automatically during the removal of @data.
795 *
796 * Return: %0 if array property (package) with @name has been found (success),
797 * %-EINVAL if the arguments are invalid,
798 * %-EINVAL if the property doesn't exist,
799 * %-EPROTO if the property is not a package or the type of its elements
800 * doesn't match @type.
801 */
802static int acpi_data_get_property_array(const struct acpi_device_data *data,
803 const char *name,
804 acpi_object_type type,
805 const union acpi_object **obj)
806{
807 const union acpi_object *prop;
808 int ret, i;
809
810 ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop);
811 if (ret)
812 return ret;
813
814 if (type != ACPI_TYPE_ANY) {
815 /* Check that all elements are of correct type. */
816 for (i = 0; i < prop->package.count; i++)
817 if (prop->package.elements[i].type != type)
818 return -EPROTO;
819 }
820 if (obj)
821 *obj = prop;
822
823 return 0;
824}
825
826static struct fwnode_handle *
827acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
828 const char *childname)
829{
830 struct fwnode_handle *child;
831
832 fwnode_for_each_child_node(fwnode, child) {
833 if (is_acpi_data_node(child)) {
834 if (acpi_data_node_match(child, childname))
835 return child;
836 continue;
837 }
838
839 if (!strncmp(acpi_device_bid(to_acpi_device_node(child)),
840 childname, ACPI_NAMESEG_SIZE))
841 return child;
842 }
843
844 return NULL;
845}
846
847static unsigned int acpi_fwnode_get_args_count(struct fwnode_handle *fwnode,
848 const char *nargs_prop)
849{
850 const struct acpi_device_data *data;
851 const union acpi_object *obj;
852 int ret;
853
854 data = acpi_device_data_of_node(fwnode);
855 if (!data)
856 return 0;
857
858 ret = acpi_data_get_property(data, nargs_prop, ACPI_TYPE_INTEGER, &obj);
859 if (ret)
860 return 0;
861
862 return obj->integer.value;
863}
864
865static int acpi_get_ref_args(struct fwnode_reference_args *args,
866 struct fwnode_handle *ref_fwnode,
867 const char *nargs_prop,
868 const union acpi_object **element,
869 const union acpi_object *end, size_t num_args)
870{
871 u32 nargs = 0, i;
872
873 if (nargs_prop)
874 num_args = acpi_fwnode_get_args_count(ref_fwnode, nargs_prop);
875
876 /*
877 * Assume the following integer elements are all args. Stop counting on
878 * the first reference (possibly represented as a string) or end of the
879 * package arguments. In case of neither reference, nor integer, return
880 * an error, we can't parse it.
881 */
882 for (i = 0; (*element) + i < end && i < num_args; i++) {
883 acpi_object_type type = (*element)[i].type;
884
885 if (type == ACPI_TYPE_LOCAL_REFERENCE || type == ACPI_TYPE_STRING)
886 break;
887
888 if (type == ACPI_TYPE_INTEGER)
889 nargs++;
890 else
891 return -EINVAL;
892 }
893
894 if (nargs > NR_FWNODE_REFERENCE_ARGS)
895 return -EINVAL;
896
897 if (args) {
898 args->fwnode = ref_fwnode;
899 args->nargs = nargs;
900 for (i = 0; i < nargs; i++)
901 args->args[i] = (*element)[i].integer.value;
902 }
903
904 (*element) += nargs;
905
906 return 0;
907}
908
909static struct fwnode_handle *acpi_parse_string_ref(const struct fwnode_handle *fwnode,
910 const char *refstring)
911{
912 acpi_handle scope, handle;
913 struct acpi_data_node *dn;
914 struct acpi_device *device;
915 acpi_status status;
916
917 if (is_acpi_device_node(fwnode)) {
918 scope = to_acpi_device_node(fwnode)->handle;
919 } else if (is_acpi_data_node(fwnode)) {
920 scope = to_acpi_data_node(fwnode)->handle;
921 } else {
922 pr_debug("Bad node type for node %pfw\n", fwnode);
923 return NULL;
924 }
925
926 status = acpi_get_handle(scope, refstring, &handle);
927 if (ACPI_FAILURE(status)) {
928 acpi_handle_debug(scope, "Unable to get an ACPI handle for %s\n",
929 refstring);
930 return NULL;
931 }
932
933 device = acpi_fetch_acpi_dev(handle);
934 if (device)
935 return acpi_fwnode_handle(device);
936
937 status = acpi_get_data_full(handle, acpi_nondev_subnode_tag,
938 (void **)&dn, NULL);
939 if (ACPI_FAILURE(status) || !dn) {
940 acpi_handle_debug(handle, "Subnode not found\n");
941 return NULL;
942 }
943
944 return &dn->fwnode;
945}
946
947static int acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
948 const char *propname, const char *nargs_prop,
949 unsigned int args_count, unsigned int index,
950 struct fwnode_reference_args *args)
951{
952 const union acpi_object *element, *end;
953 const union acpi_object *obj;
954 const struct acpi_device_data *data;
955 struct fwnode_handle *ref_fwnode;
956 struct acpi_device *device;
957 int ret, idx = 0;
958
959 data = acpi_device_data_of_node(fwnode);
960 if (!data)
961 return -ENOENT;
962
963 ret = acpi_data_get_property(data, propname, ACPI_TYPE_ANY, &obj);
964 if (ret)
965 return ret == -EINVAL ? -ENOENT : -EINVAL;
966
967 switch (obj->type) {
968 case ACPI_TYPE_LOCAL_REFERENCE:
969 /* Plain single reference without arguments. */
970 if (index)
971 return -ENOENT;
972
973 device = acpi_fetch_acpi_dev(obj->reference.handle);
974 if (!device)
975 return -EINVAL;
976
977 if (!args)
978 return 0;
979
980 args->fwnode = acpi_fwnode_handle(device);
981 args->nargs = 0;
982
983 return 0;
984 case ACPI_TYPE_STRING:
985 if (index)
986 return -ENOENT;
987
988 ref_fwnode = acpi_parse_string_ref(fwnode, obj->string.pointer);
989 if (!ref_fwnode)
990 return -EINVAL;
991
992 args->fwnode = ref_fwnode;
993 args->nargs = 0;
994
995 return 0;
996 case ACPI_TYPE_PACKAGE:
997 /*
998 * If it is not a single reference, then it is a package of
999 * references, followed by number of ints as follows:
1000 *
1001 * Package () { REF, INT, REF, INT, INT }
1002 *
1003 * Here, REF may be either a local reference or a string. The
1004 * index argument is then used to determine which reference the
1005 * caller wants (along with the arguments).
1006 */
1007 break;
1008 default:
1009 return -EINVAL;
1010 }
1011
1012 if (index >= obj->package.count)
1013 return -ENOENT;
1014
1015 element = obj->package.elements;
1016 end = element + obj->package.count;
1017
1018 while (element < end) {
1019 switch (element->type) {
1020 case ACPI_TYPE_LOCAL_REFERENCE:
1021 device = acpi_fetch_acpi_dev(element->reference.handle);
1022 if (!device)
1023 return -EINVAL;
1024
1025 element++;
1026 ret = acpi_get_ref_args(idx == index ? args : NULL,
1027 acpi_fwnode_handle(device),
1028 nargs_prop, &element, end,
1029 args_count);
1030 if (ret < 0)
1031 return ret;
1032
1033 if (idx == index)
1034 return 0;
1035
1036 break;
1037 case ACPI_TYPE_STRING:
1038 ref_fwnode = acpi_parse_string_ref(fwnode,
1039 element->string.pointer);
1040 if (!ref_fwnode)
1041 return -EINVAL;
1042
1043 element++;
1044 ret = acpi_get_ref_args(idx == index ? args : NULL,
1045 ref_fwnode, nargs_prop, &element, end,
1046 args_count);
1047 if (ret < 0)
1048 return ret;
1049
1050 if (idx == index)
1051 return 0;
1052
1053 break;
1054 case ACPI_TYPE_INTEGER:
1055 if (idx == index)
1056 return -ENOENT;
1057 element++;
1058 break;
1059 default:
1060 return -EINVAL;
1061 }
1062
1063 idx++;
1064 }
1065
1066 return -ENOENT;
1067}
1068
1069/**
1070 * __acpi_node_get_property_reference - returns handle to the referenced object
1071 * @fwnode: Firmware node to get the property from
1072 * @propname: Name of the property
1073 * @index: Index of the reference to return
1074 * @num_args: Maximum number of arguments after each reference
1075 * @args: Location to store the returned reference with optional arguments
1076 * (may be NULL)
1077 *
1078 * Find property with @name, verifify that it is a package containing at least
1079 * one object reference and if so, store the ACPI device object pointer to the
1080 * target object in @args->adev. If the reference includes arguments, store
1081 * them in the @args->args[] array.
1082 *
1083 * If there's more than one reference in the property value package, @index is
1084 * used to select the one to return.
1085 *
1086 * It is possible to leave holes in the property value set like in the
1087 * example below:
1088 *
1089 * Package () {
1090 * "cs-gpios",
1091 * Package () {
1092 * ^GPIO, 19, 0, 0,
1093 * ^GPIO, 20, 0, 0,
1094 * 0,
1095 * ^GPIO, 21, 0, 0,
1096 * }
1097 * }
1098 *
1099 * Calling this function with index %2 or index %3 return %-ENOENT. If the
1100 * property does not contain any more values %-ENOENT is returned. The NULL
1101 * entry must be single integer and preferably contain value %0.
1102 *
1103 * Return: %0 on success, negative error code on failure.
1104 */
1105int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
1106 const char *propname, size_t index,
1107 size_t num_args,
1108 struct fwnode_reference_args *args)
1109{
1110 return acpi_fwnode_get_reference_args(fwnode, propname, NULL, num_args, index, args);
1111}
1112EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);
1113
1114static int acpi_data_prop_read_single(const struct acpi_device_data *data,
1115 const char *propname,
1116 enum dev_prop_type proptype, void *val)
1117{
1118 const union acpi_object *obj;
1119 int ret = 0;
1120
1121 if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64)
1122 ret = acpi_data_get_property(data, propname, ACPI_TYPE_INTEGER, &obj);
1123 else if (proptype == DEV_PROP_STRING)
1124 ret = acpi_data_get_property(data, propname, ACPI_TYPE_STRING, &obj);
1125 if (ret)
1126 return ret;
1127
1128 switch (proptype) {
1129 case DEV_PROP_U8:
1130 if (obj->integer.value > U8_MAX)
1131 return -EOVERFLOW;
1132 if (val)
1133 *(u8 *)val = obj->integer.value;
1134 break;
1135 case DEV_PROP_U16:
1136 if (obj->integer.value > U16_MAX)
1137 return -EOVERFLOW;
1138 if (val)
1139 *(u16 *)val = obj->integer.value;
1140 break;
1141 case DEV_PROP_U32:
1142 if (obj->integer.value > U32_MAX)
1143 return -EOVERFLOW;
1144 if (val)
1145 *(u32 *)val = obj->integer.value;
1146 break;
1147 case DEV_PROP_U64:
1148 if (val)
1149 *(u64 *)val = obj->integer.value;
1150 break;
1151 case DEV_PROP_STRING:
1152 if (val)
1153 *(char **)val = obj->string.pointer;
1154 return 1;
1155 default:
1156 return -EINVAL;
1157 }
1158
1159 /* When no storage provided return number of available values */
1160 return val ? 0 : 1;
1161}
1162
1163#define acpi_copy_property_array_uint(items, val, nval) \
1164 ({ \
1165 typeof(items) __items = items; \
1166 typeof(val) __val = val; \
1167 typeof(nval) __nval = nval; \
1168 size_t i; \
1169 int ret = 0; \
1170 \
1171 for (i = 0; i < __nval; i++) { \
1172 if (__items->type == ACPI_TYPE_BUFFER) { \
1173 __val[i] = __items->buffer.pointer[i]; \
1174 continue; \
1175 } \
1176 if (__items[i].type != ACPI_TYPE_INTEGER) { \
1177 ret = -EPROTO; \
1178 break; \
1179 } \
1180 if (__items[i].integer.value > _Generic(__val, \
1181 u8 *: U8_MAX, \
1182 u16 *: U16_MAX, \
1183 u32 *: U32_MAX, \
1184 u64 *: U64_MAX)) { \
1185 ret = -EOVERFLOW; \
1186 break; \
1187 } \
1188 \
1189 __val[i] = __items[i].integer.value; \
1190 } \
1191 ret; \
1192 })
1193
1194static int acpi_copy_property_array_string(const union acpi_object *items,
1195 char **val, size_t nval)
1196{
1197 int i;
1198
1199 for (i = 0; i < nval; i++) {
1200 if (items[i].type != ACPI_TYPE_STRING)
1201 return -EPROTO;
1202
1203 val[i] = items[i].string.pointer;
1204 }
1205 return nval;
1206}
1207
1208static int acpi_data_prop_read(const struct acpi_device_data *data,
1209 const char *propname,
1210 enum dev_prop_type proptype,
1211 void *val, size_t nval)
1212{
1213 const union acpi_object *obj;
1214 const union acpi_object *items;
1215 int ret;
1216
1217 if (nval == 1 || !val) {
1218 ret = acpi_data_prop_read_single(data, propname, proptype, val);
1219 /*
1220 * The overflow error means that the property is there and it is
1221 * single-value, but its type does not match, so return.
1222 */
1223 if (ret >= 0 || ret == -EOVERFLOW)
1224 return ret;
1225
1226 /*
1227 * Reading this property as a single-value one failed, but its
1228 * value may still be represented as one-element array, so
1229 * continue.
1230 */
1231 }
1232
1233 ret = acpi_data_get_property_array(data, propname, ACPI_TYPE_ANY, &obj);
1234 if (ret && proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64)
1235 ret = acpi_data_get_property(data, propname, ACPI_TYPE_BUFFER,
1236 &obj);
1237 if (ret)
1238 return ret;
1239
1240 if (!val) {
1241 if (obj->type == ACPI_TYPE_BUFFER)
1242 return obj->buffer.length;
1243
1244 return obj->package.count;
1245 }
1246
1247 switch (proptype) {
1248 case DEV_PROP_STRING:
1249 break;
1250 default:
1251 if (obj->type == ACPI_TYPE_BUFFER) {
1252 if (nval > obj->buffer.length)
1253 return -EOVERFLOW;
1254 } else {
1255 if (nval > obj->package.count)
1256 return -EOVERFLOW;
1257 }
1258 break;
1259 }
1260
1261 if (obj->type == ACPI_TYPE_BUFFER) {
1262 if (proptype != DEV_PROP_U8)
1263 return -EPROTO;
1264 items = obj;
1265 } else {
1266 items = obj->package.elements;
1267 }
1268
1269 switch (proptype) {
1270 case DEV_PROP_U8:
1271 ret = acpi_copy_property_array_uint(items, (u8 *)val, nval);
1272 break;
1273 case DEV_PROP_U16:
1274 ret = acpi_copy_property_array_uint(items, (u16 *)val, nval);
1275 break;
1276 case DEV_PROP_U32:
1277 ret = acpi_copy_property_array_uint(items, (u32 *)val, nval);
1278 break;
1279 case DEV_PROP_U64:
1280 ret = acpi_copy_property_array_uint(items, (u64 *)val, nval);
1281 break;
1282 case DEV_PROP_STRING:
1283 nval = min(nval, obj->package.count);
1284 if (nval == 0)
1285 return -ENODATA;
1286
1287 ret = acpi_copy_property_array_string(items, (char **)val, nval);
1288 break;
1289 default:
1290 ret = -EINVAL;
1291 break;
1292 }
1293 return ret;
1294}
1295
1296/**
1297 * acpi_node_prop_read - retrieve the value of an ACPI property with given name.
1298 * @fwnode: Firmware node to get the property from.
1299 * @propname: Name of the property.
1300 * @proptype: Expected property type.
1301 * @val: Location to store the property value (if not %NULL).
1302 * @nval: Size of the array pointed to by @val.
1303 *
1304 * If @val is %NULL, return the number of array elements comprising the value
1305 * of the property. Otherwise, read at most @nval values to the array at the
1306 * location pointed to by @val.
1307 */
1308static int acpi_node_prop_read(const struct fwnode_handle *fwnode,
1309 const char *propname, enum dev_prop_type proptype,
1310 void *val, size_t nval)
1311{
1312 return acpi_data_prop_read(acpi_device_data_of_node(fwnode),
1313 propname, proptype, val, nval);
1314}
1315
1316static int stop_on_next(struct acpi_device *adev, void *data)
1317{
1318 struct acpi_device **ret_p = data;
1319
1320 if (!*ret_p) {
1321 *ret_p = adev;
1322 return 1;
1323 }
1324
1325 /* Skip until the "previous" object is found. */
1326 if (*ret_p == adev)
1327 *ret_p = NULL;
1328
1329 return 0;
1330}
1331
1332/*
1333 * acpi_get_next_subnode - Return the next child node handle for a fwnode
1334 * @fwnode: Firmware node to find the next child node for.
1335 * @child: Handle to one of the device's child nodes or a null handle.
1336 */
1337static struct fwnode_handle *
1338acpi_get_next_subnode(const struct fwnode_handle *fwnode,
1339 struct fwnode_handle *child)
1340{
1341 struct acpi_device *adev = to_acpi_device_node(fwnode);
1342
1343 if ((!child || is_acpi_device_node(child)) && adev) {
1344 struct acpi_device *child_adev = to_acpi_device_node(child);
1345
1346 acpi_dev_for_each_child(adev, stop_on_next, &child_adev);
1347 if (child_adev)
1348 return acpi_fwnode_handle(child_adev);
1349
1350 child = NULL;
1351 }
1352
1353 if (!child || is_acpi_data_node(child)) {
1354 const struct acpi_data_node *data = to_acpi_data_node(fwnode);
1355 const struct list_head *head;
1356 struct list_head *next;
1357 struct acpi_data_node *dn;
1358
1359 /*
1360 * We can have a combination of device and data nodes, e.g. with
1361 * hierarchical _DSD properties. Make sure the adev pointer is
1362 * restored before going through data nodes, otherwise we will
1363 * be looking for data_nodes below the last device found instead
1364 * of the common fwnode shared by device_nodes and data_nodes.
1365 */
1366 adev = to_acpi_device_node(fwnode);
1367 if (adev)
1368 head = &adev->data.subnodes;
1369 else if (data)
1370 head = &data->data.subnodes;
1371 else
1372 return NULL;
1373
1374 if (list_empty(head))
1375 return NULL;
1376
1377 if (child) {
1378 dn = to_acpi_data_node(child);
1379 next = dn->sibling.next;
1380 if (next == head)
1381 return NULL;
1382
1383 dn = list_entry(next, struct acpi_data_node, sibling);
1384 } else {
1385 dn = list_first_entry(head, struct acpi_data_node, sibling);
1386 }
1387 return &dn->fwnode;
1388 }
1389 return NULL;
1390}
1391
1392/*
1393 * acpi_get_next_present_subnode - Return the next present child node handle
1394 * @fwnode: Firmware node to find the next child node for.
1395 * @child: Handle to one of the device's child nodes or a null handle.
1396 *
1397 * Like acpi_get_next_subnode(), but the device nodes returned by
1398 * acpi_get_next_present_subnode() are guaranteed to be present.
1399 *
1400 * Returns: The fwnode handle of the next present sub-node.
1401 */
1402static struct fwnode_handle *
1403acpi_get_next_present_subnode(const struct fwnode_handle *fwnode,
1404 struct fwnode_handle *child)
1405{
1406 do {
1407 child = acpi_get_next_subnode(fwnode, child);
1408 } while (is_acpi_device_node(child) &&
1409 !acpi_device_is_present(to_acpi_device_node(child)));
1410
1411 return child;
1412}
1413
1414/**
1415 * acpi_node_get_parent - Return parent fwnode of this fwnode
1416 * @fwnode: Firmware node whose parent to get
1417 *
1418 * Returns parent node of an ACPI device or data firmware node or %NULL if
1419 * not available.
1420 */
1421static struct fwnode_handle *
1422acpi_node_get_parent(const struct fwnode_handle *fwnode)
1423{
1424 if (is_acpi_data_node(fwnode)) {
1425 /* All data nodes have parent pointer so just return that */
1426 return to_acpi_data_node(fwnode)->parent;
1427 }
1428 if (is_acpi_device_node(fwnode)) {
1429 struct acpi_device *parent;
1430
1431 parent = acpi_dev_parent(to_acpi_device_node(fwnode));
1432 if (parent)
1433 return acpi_fwnode_handle(parent);
1434 }
1435
1436 return NULL;
1437}
1438
1439/*
1440 * Return true if the node is an ACPI graph node. Called on either ports
1441 * or endpoints.
1442 */
1443static bool is_acpi_graph_node(struct fwnode_handle *fwnode,
1444 const char *str)
1445{
1446 unsigned int len = strlen(str);
1447 const char *name;
1448
1449 if (!len || !is_acpi_data_node(fwnode))
1450 return false;
1451
1452 name = to_acpi_data_node(fwnode)->name;
1453
1454 return (fwnode_property_present(fwnode, "reg") &&
1455 !strncmp(name, str, len) && name[len] == '@') ||
1456 fwnode_property_present(fwnode, str);
1457}
1458
1459/**
1460 * acpi_graph_get_next_endpoint - Get next endpoint ACPI firmware node
1461 * @fwnode: Pointer to the parent firmware node
1462 * @prev: Previous endpoint node or %NULL to get the first
1463 *
1464 * Looks up next endpoint ACPI firmware node below a given @fwnode. Returns
1465 * %NULL if there is no next endpoint or in case of error. In case of success
1466 * the next endpoint is returned.
1467 */
1468static struct fwnode_handle *acpi_graph_get_next_endpoint(
1469 const struct fwnode_handle *fwnode, struct fwnode_handle *prev)
1470{
1471 struct fwnode_handle *port = NULL;
1472 struct fwnode_handle *endpoint;
1473
1474 if (!prev) {
1475 do {
1476 port = acpi_get_next_subnode(fwnode, port);
1477 /*
1478 * The names of the port nodes begin with "port@"
1479 * followed by the number of the port node and they also
1480 * have a "reg" property that also has the number of the
1481 * port node. For compatibility reasons a node is also
1482 * recognised as a port node from the "port" property.
1483 */
1484 if (is_acpi_graph_node(port, "port"))
1485 break;
1486 } while (port);
1487 } else {
1488 port = fwnode_get_parent(prev);
1489 }
1490
1491 if (!port)
1492 return NULL;
1493
1494 do {
1495 endpoint = acpi_get_next_subnode(port, prev);
1496 if (endpoint)
1497 break;
1498
1499 prev = NULL;
1500
1501 do {
1502 port = acpi_get_next_subnode(fwnode, port);
1503 } while (port && !is_acpi_graph_node(port, "port"));
1504 } while (port);
1505
1506 /*
1507 * The names of the endpoint nodes begin with "endpoint@" followed by
1508 * the number of the endpoint node and they also have a "reg" property
1509 * that also has the number of the endpoint node. For compatibility
1510 * reasons a node is also recognised as an endpoint node from the
1511 * "endpoint" property.
1512 */
1513 if (!is_acpi_graph_node(endpoint, "endpoint"))
1514 return NULL;
1515
1516 return endpoint;
1517}
1518
1519/**
1520 * acpi_graph_get_child_prop_value - Return a child with a given property value
1521 * @fwnode: device fwnode
1522 * @prop_name: The name of the property to look for
1523 * @val: the desired property value
1524 *
1525 * Return the port node corresponding to a given port number. Returns
1526 * the child node on success, NULL otherwise.
1527 */
1528static struct fwnode_handle *acpi_graph_get_child_prop_value(
1529 const struct fwnode_handle *fwnode, const char *prop_name,
1530 unsigned int val)
1531{
1532 struct fwnode_handle *child;
1533
1534 fwnode_for_each_child_node(fwnode, child) {
1535 u32 nr;
1536
1537 if (fwnode_property_read_u32(child, prop_name, &nr))
1538 continue;
1539
1540 if (val == nr)
1541 return child;
1542 }
1543
1544 return NULL;
1545}
1546
1547
1548/**
1549 * acpi_graph_get_remote_endpoint - Parses and returns remote end of an endpoint
1550 * @__fwnode: Endpoint firmware node pointing to a remote device
1551 *
1552 * Returns the remote endpoint corresponding to @__fwnode. NULL on error.
1553 */
1554static struct fwnode_handle *
1555acpi_graph_get_remote_endpoint(const struct fwnode_handle *__fwnode)
1556{
1557 struct fwnode_handle *fwnode;
1558 unsigned int port_nr, endpoint_nr;
1559 struct fwnode_reference_args args;
1560 int ret;
1561
1562 memset(&args, 0, sizeof(args));
1563 ret = acpi_node_get_property_reference(__fwnode, "remote-endpoint", 0,
1564 &args);
1565 if (ret)
1566 return NULL;
1567
1568 /* Direct endpoint reference? */
1569 if (!is_acpi_device_node(args.fwnode))
1570 return args.nargs ? NULL : args.fwnode;
1571
1572 /*
1573 * Always require two arguments with the reference: port and
1574 * endpoint indices.
1575 */
1576 if (args.nargs != 2)
1577 return NULL;
1578
1579 fwnode = args.fwnode;
1580 port_nr = args.args[0];
1581 endpoint_nr = args.args[1];
1582
1583 fwnode = acpi_graph_get_child_prop_value(fwnode, "port", port_nr);
1584
1585 return acpi_graph_get_child_prop_value(fwnode, "endpoint", endpoint_nr);
1586}
1587
1588static bool acpi_fwnode_device_is_available(const struct fwnode_handle *fwnode)
1589{
1590 if (!is_acpi_device_node(fwnode))
1591 return true;
1592
1593 return acpi_device_is_present(to_acpi_device_node(fwnode));
1594}
1595
1596static const void *
1597acpi_fwnode_device_get_match_data(const struct fwnode_handle *fwnode,
1598 const struct device *dev)
1599{
1600 return acpi_device_get_match_data(dev);
1601}
1602
1603static bool acpi_fwnode_device_dma_supported(const struct fwnode_handle *fwnode)
1604{
1605 return acpi_dma_supported(to_acpi_device_node(fwnode));
1606}
1607
1608static enum dev_dma_attr
1609acpi_fwnode_device_get_dma_attr(const struct fwnode_handle *fwnode)
1610{
1611 return acpi_get_dma_attr(to_acpi_device_node(fwnode));
1612}
1613
1614static bool acpi_fwnode_property_present(const struct fwnode_handle *fwnode,
1615 const char *propname)
1616{
1617 return !acpi_node_prop_get(fwnode, propname, NULL);
1618}
1619
1620static int
1621acpi_fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
1622 const char *propname,
1623 unsigned int elem_size, void *val,
1624 size_t nval)
1625{
1626 enum dev_prop_type type;
1627
1628 switch (elem_size) {
1629 case sizeof(u8):
1630 type = DEV_PROP_U8;
1631 break;
1632 case sizeof(u16):
1633 type = DEV_PROP_U16;
1634 break;
1635 case sizeof(u32):
1636 type = DEV_PROP_U32;
1637 break;
1638 case sizeof(u64):
1639 type = DEV_PROP_U64;
1640 break;
1641 default:
1642 return -ENXIO;
1643 }
1644
1645 return acpi_node_prop_read(fwnode, propname, type, val, nval);
1646}
1647
1648static int
1649acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
1650 const char *propname, const char **val,
1651 size_t nval)
1652{
1653 return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
1654 val, nval);
1655}
1656
1657static const char *acpi_fwnode_get_name(const struct fwnode_handle *fwnode)
1658{
1659 const struct acpi_device *adev;
1660 struct fwnode_handle *parent;
1661
1662 /* Is this the root node? */
1663 parent = fwnode_get_parent(fwnode);
1664 if (!parent)
1665 return "\\";
1666
1667 fwnode_handle_put(parent);
1668
1669 if (is_acpi_data_node(fwnode)) {
1670 const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
1671
1672 return dn->name;
1673 }
1674
1675 adev = to_acpi_device_node(fwnode);
1676 if (WARN_ON(!adev))
1677 return NULL;
1678
1679 return acpi_device_bid(adev);
1680}
1681
1682static const char *
1683acpi_fwnode_get_name_prefix(const struct fwnode_handle *fwnode)
1684{
1685 struct fwnode_handle *parent;
1686
1687 /* Is this the root node? */
1688 parent = fwnode_get_parent(fwnode);
1689 if (!parent)
1690 return "";
1691
1692 /* Is this 2nd node from the root? */
1693 parent = fwnode_get_next_parent(parent);
1694 if (!parent)
1695 return "";
1696
1697 fwnode_handle_put(parent);
1698
1699 /* ACPI device or data node. */
1700 return ".";
1701}
1702
1703static struct fwnode_handle *
1704acpi_fwnode_get_parent(struct fwnode_handle *fwnode)
1705{
1706 return acpi_node_get_parent(fwnode);
1707}
1708
1709static int acpi_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
1710 struct fwnode_endpoint *endpoint)
1711{
1712 struct fwnode_handle *port_fwnode = fwnode_get_parent(fwnode);
1713
1714 endpoint->local_fwnode = fwnode;
1715
1716 if (fwnode_property_read_u32(port_fwnode, "reg", &endpoint->port))
1717 fwnode_property_read_u32(port_fwnode, "port", &endpoint->port);
1718 if (fwnode_property_read_u32(fwnode, "reg", &endpoint->id))
1719 fwnode_property_read_u32(fwnode, "endpoint", &endpoint->id);
1720
1721 fwnode_handle_put(port_fwnode);
1722 return 0;
1723}
1724
1725static int acpi_fwnode_irq_get(const struct fwnode_handle *fwnode,
1726 unsigned int index)
1727{
1728 struct resource res;
1729 int ret;
1730
1731 ret = acpi_irq_get(ACPI_HANDLE_FWNODE(fwnode), index, &res);
1732 if (ret)
1733 return ret;
1734
1735 return res.start;
1736}
1737
1738#define DECLARE_ACPI_FWNODE_OPS(ops) \
1739 const struct fwnode_operations ops = { \
1740 .device_is_available = acpi_fwnode_device_is_available, \
1741 .device_get_match_data = acpi_fwnode_device_get_match_data, \
1742 .device_dma_supported = \
1743 acpi_fwnode_device_dma_supported, \
1744 .device_get_dma_attr = acpi_fwnode_device_get_dma_attr, \
1745 .property_present = acpi_fwnode_property_present, \
1746 .property_read_bool = acpi_fwnode_property_present, \
1747 .property_read_int_array = \
1748 acpi_fwnode_property_read_int_array, \
1749 .property_read_string_array = \
1750 acpi_fwnode_property_read_string_array, \
1751 .get_parent = acpi_node_get_parent, \
1752 .get_next_child_node = acpi_get_next_present_subnode, \
1753 .get_named_child_node = acpi_fwnode_get_named_child_node, \
1754 .get_name = acpi_fwnode_get_name, \
1755 .get_name_prefix = acpi_fwnode_get_name_prefix, \
1756 .get_reference_args = acpi_fwnode_get_reference_args, \
1757 .graph_get_next_endpoint = \
1758 acpi_graph_get_next_endpoint, \
1759 .graph_get_remote_endpoint = \
1760 acpi_graph_get_remote_endpoint, \
1761 .graph_get_port_parent = acpi_fwnode_get_parent, \
1762 .graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint, \
1763 .irq_get = acpi_fwnode_irq_get, \
1764 }; \
1765 EXPORT_SYMBOL_GPL(ops)
1766
1767DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
1768DECLARE_ACPI_FWNODE_OPS(acpi_data_fwnode_ops);
1769const struct fwnode_operations acpi_static_fwnode_ops;
1770
1771bool is_acpi_device_node(const struct fwnode_handle *fwnode)
1772{
1773 return !IS_ERR_OR_NULL(fwnode) &&
1774 fwnode->ops == &acpi_device_fwnode_ops;
1775}
1776EXPORT_SYMBOL(is_acpi_device_node);
1777
1778bool is_acpi_data_node(const struct fwnode_handle *fwnode)
1779{
1780 return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &acpi_data_fwnode_ops;
1781}
1782EXPORT_SYMBOL(is_acpi_data_node);