2 * ACPI device specific properties support.
4 * Copyright (C) 2014, Intel Corporation
7 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
8 * Darren Hart <dvhart@linux.intel.com>
9 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
16 #include <linux/acpi.h>
17 #include <linux/device.h>
18 #include <linux/export.h>
22 static int acpi_data_get_property_array(const struct acpi_device_data *data,
24 acpi_object_type type,
25 const union acpi_object **obj);
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.
35 static const guid_t prp_guids[] = {
36 /* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
37 GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c,
38 0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01),
39 /* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */
40 GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3,
41 0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4),
42 /* External facing port GUID: efcc06cc-73ac-4bc3-bff0-76143807c389 */
43 GUID_INIT(0xefcc06cc, 0x73ac, 0x4bc3,
44 0xbf, 0xf0, 0x76, 0x14, 0x38, 0x07, 0xc3, 0x89),
47 /* ACPI _DSD data subnodes GUID: dbb8e3e6-5886-4ba6-8795-1319f52a966b */
48 static const guid_t ads_guid =
49 GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
50 0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b);
52 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
53 const union acpi_object *desc,
54 struct acpi_device_data *data,
55 struct fwnode_handle *parent);
56 static bool acpi_extract_properties(const union acpi_object *desc,
57 struct acpi_device_data *data);
59 static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
61 const union acpi_object *link,
62 struct list_head *list,
63 struct fwnode_handle *parent)
65 struct acpi_data_node *dn;
68 dn = kzalloc(sizeof(*dn), GFP_KERNEL);
72 dn->name = link->package.elements[0].string.pointer;
73 dn->fwnode.ops = &acpi_data_fwnode_ops;
75 INIT_LIST_HEAD(&dn->data.properties);
76 INIT_LIST_HEAD(&dn->data.subnodes);
78 result = acpi_extract_properties(desc, &dn->data);
85 * The scope for the subnode object lookup is the one of the
86 * namespace node (device) containing the object that has
87 * returned the package. That is, it's the scope of that
90 status = acpi_get_parent(handle, &scope);
91 if (ACPI_SUCCESS(status)
92 && acpi_enumerate_nondev_subnodes(scope, desc, &dn->data,
95 } else if (acpi_enumerate_nondev_subnodes(NULL, desc, &dn->data,
102 dn->data.pointer = desc;
103 list_add_tail(&dn->sibling, list);
108 acpi_handle_debug(handle, "Invalid properties/subnodes data, skipping\n");
112 static bool acpi_nondev_subnode_data_ok(acpi_handle handle,
113 const union acpi_object *link,
114 struct list_head *list,
115 struct fwnode_handle *parent)
117 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
120 status = acpi_evaluate_object_typed(handle, NULL, NULL, &buf,
122 if (ACPI_FAILURE(status))
125 if (acpi_nondev_subnode_extract(buf.pointer, handle, link, list,
129 ACPI_FREE(buf.pointer);
133 static bool acpi_nondev_subnode_ok(acpi_handle scope,
134 const union acpi_object *link,
135 struct list_head *list,
136 struct fwnode_handle *parent)
144 status = acpi_get_handle(scope, link->package.elements[1].string.pointer,
146 if (ACPI_FAILURE(status))
149 return acpi_nondev_subnode_data_ok(handle, link, list, parent);
152 static int acpi_add_nondev_subnodes(acpi_handle scope,
153 const union acpi_object *links,
154 struct list_head *list,
155 struct fwnode_handle *parent)
160 for (i = 0; i < links->package.count; i++) {
161 const union acpi_object *link, *desc;
165 link = &links->package.elements[i];
166 /* Only two elements allowed. */
167 if (link->package.count != 2)
170 /* The first one must be a string. */
171 if (link->package.elements[0].type != ACPI_TYPE_STRING)
174 /* The second one may be a string, a reference or a package. */
175 switch (link->package.elements[1].type) {
176 case ACPI_TYPE_STRING:
177 result = acpi_nondev_subnode_ok(scope, link, list,
180 case ACPI_TYPE_LOCAL_REFERENCE:
181 handle = link->package.elements[1].reference.handle;
182 result = acpi_nondev_subnode_data_ok(handle, link, list,
185 case ACPI_TYPE_PACKAGE:
186 desc = &link->package.elements[1];
187 result = acpi_nondev_subnode_extract(desc, NULL, link,
200 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
201 const union acpi_object *desc,
202 struct acpi_device_data *data,
203 struct fwnode_handle *parent)
207 /* Look for the ACPI data subnodes GUID. */
208 for (i = 0; i < desc->package.count; i += 2) {
209 const union acpi_object *guid, *links;
211 guid = &desc->package.elements[i];
212 links = &desc->package.elements[i + 1];
215 * The first element must be a GUID and the second one must be
218 if (guid->type != ACPI_TYPE_BUFFER ||
219 guid->buffer.length != 16 ||
220 links->type != ACPI_TYPE_PACKAGE)
223 if (!guid_equal((guid_t *)guid->buffer.pointer, &ads_guid))
226 return acpi_add_nondev_subnodes(scope, links, &data->subnodes,
233 static bool acpi_property_value_ok(const union acpi_object *value)
238 * The value must be an integer, a string, a reference, or a package
239 * whose every element must be an integer, a string, or a reference.
241 switch (value->type) {
242 case ACPI_TYPE_INTEGER:
243 case ACPI_TYPE_STRING:
244 case ACPI_TYPE_LOCAL_REFERENCE:
247 case ACPI_TYPE_PACKAGE:
248 for (j = 0; j < value->package.count; j++)
249 switch (value->package.elements[j].type) {
250 case ACPI_TYPE_INTEGER:
251 case ACPI_TYPE_STRING:
252 case ACPI_TYPE_LOCAL_REFERENCE:
264 static bool acpi_properties_format_valid(const union acpi_object *properties)
268 for (i = 0; i < properties->package.count; i++) {
269 const union acpi_object *property;
271 property = &properties->package.elements[i];
273 * Only two elements allowed, the first one must be a string and
274 * the second one has to satisfy certain conditions.
276 if (property->package.count != 2
277 || property->package.elements[0].type != ACPI_TYPE_STRING
278 || !acpi_property_value_ok(&property->package.elements[1]))
284 static void acpi_init_of_compatible(struct acpi_device *adev)
286 const union acpi_object *of_compatible;
289 ret = acpi_data_get_property_array(&adev->data, "compatible",
290 ACPI_TYPE_STRING, &of_compatible);
292 ret = acpi_dev_get_property(adev, "compatible",
293 ACPI_TYPE_STRING, &of_compatible);
296 && adev->parent->flags.of_compatible_ok)
302 adev->data.of_compatible = of_compatible;
305 adev->flags.of_compatible_ok = 1;
308 static bool acpi_is_property_guid(const guid_t *guid)
312 for (i = 0; i < ARRAY_SIZE(prp_guids); i++) {
313 if (guid_equal(guid, &prp_guids[i]))
320 struct acpi_device_properties *
321 acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
322 const union acpi_object *properties)
324 struct acpi_device_properties *props;
326 props = kzalloc(sizeof(*props), GFP_KERNEL);
328 INIT_LIST_HEAD(&props->list);
330 props->properties = properties;
331 list_add_tail(&props->list, &data->properties);
337 static bool acpi_extract_properties(const union acpi_object *desc,
338 struct acpi_device_data *data)
342 if (desc->package.count % 2)
345 /* Look for the device properties GUID. */
346 for (i = 0; i < desc->package.count; i += 2) {
347 const union acpi_object *guid, *properties;
349 guid = &desc->package.elements[i];
350 properties = &desc->package.elements[i + 1];
353 * The first element must be a GUID and the second one must be
356 if (guid->type != ACPI_TYPE_BUFFER ||
357 guid->buffer.length != 16 ||
358 properties->type != ACPI_TYPE_PACKAGE)
361 if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
365 * We found the matching GUID. Now validate the format of the
366 * package immediately following it.
368 if (!acpi_properties_format_valid(properties))
371 acpi_data_add_props(data, (const guid_t *)guid->buffer.pointer,
375 return !list_empty(&data->properties);
378 void acpi_init_properties(struct acpi_device *adev)
380 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
381 struct acpi_hardware_id *hwid;
383 bool acpi_of = false;
385 INIT_LIST_HEAD(&adev->data.properties);
386 INIT_LIST_HEAD(&adev->data.subnodes);
392 * Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
393 * Device Tree compatible properties for this device.
395 list_for_each_entry(hwid, &adev->pnp.ids, list) {
396 if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
402 status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
404 if (ACPI_FAILURE(status))
407 if (acpi_extract_properties(buf.pointer, &adev->data)) {
408 adev->data.pointer = buf.pointer;
410 acpi_init_of_compatible(adev);
412 if (acpi_enumerate_nondev_subnodes(adev->handle, buf.pointer,
413 &adev->data, acpi_fwnode_handle(adev)))
414 adev->data.pointer = buf.pointer;
416 if (!adev->data.pointer) {
417 acpi_handle_debug(adev->handle, "Invalid _DSD data, skipping\n");
418 ACPI_FREE(buf.pointer);
422 if (acpi_of && !adev->flags.of_compatible_ok)
423 acpi_handle_info(adev->handle,
424 ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n");
426 if (!adev->data.pointer)
427 acpi_extract_apple_properties(adev);
430 static void acpi_destroy_nondev_subnodes(struct list_head *list)
432 struct acpi_data_node *dn, *next;
434 if (list_empty(list))
437 list_for_each_entry_safe_reverse(dn, next, list, sibling) {
438 acpi_destroy_nondev_subnodes(&dn->data.subnodes);
439 wait_for_completion(&dn->kobj_done);
440 list_del(&dn->sibling);
441 ACPI_FREE((void *)dn->data.pointer);
446 void acpi_free_properties(struct acpi_device *adev)
448 struct acpi_device_properties *props, *tmp;
450 acpi_destroy_nondev_subnodes(&adev->data.subnodes);
451 ACPI_FREE((void *)adev->data.pointer);
452 adev->data.of_compatible = NULL;
453 adev->data.pointer = NULL;
454 list_for_each_entry_safe(props, tmp, &adev->data.properties, list) {
455 list_del(&props->list);
461 * acpi_data_get_property - return an ACPI property with given name
462 * @data: ACPI device deta object to get the property from
463 * @name: Name of the property
464 * @type: Expected property type
465 * @obj: Location to store the property value (if not %NULL)
467 * Look up a property with @name and store a pointer to the resulting ACPI
468 * object at the location pointed to by @obj if found.
470 * Callers must not attempt to free the returned objects. These objects will be
471 * freed by the ACPI core automatically during the removal of @data.
473 * Return: %0 if property with @name has been found (success),
474 * %-EINVAL if the arguments are invalid,
475 * %-EINVAL if the property doesn't exist,
476 * %-EPROTO if the property value type doesn't match @type.
478 static int acpi_data_get_property(const struct acpi_device_data *data,
479 const char *name, acpi_object_type type,
480 const union acpi_object **obj)
482 const struct acpi_device_properties *props;
487 if (!data->pointer || list_empty(&data->properties))
490 list_for_each_entry(props, &data->properties, list) {
491 const union acpi_object *properties;
494 properties = props->properties;
495 for (i = 0; i < properties->package.count; i++) {
496 const union acpi_object *propname, *propvalue;
497 const union acpi_object *property;
499 property = &properties->package.elements[i];
501 propname = &property->package.elements[0];
502 propvalue = &property->package.elements[1];
504 if (!strcmp(name, propname->string.pointer)) {
505 if (type != ACPI_TYPE_ANY &&
506 propvalue->type != type)
519 * acpi_dev_get_property - return an ACPI property with given name.
520 * @adev: ACPI device to get the property from.
521 * @name: Name of the property.
522 * @type: Expected property type.
523 * @obj: Location to store the property value (if not %NULL).
525 int acpi_dev_get_property(const struct acpi_device *adev, const char *name,
526 acpi_object_type type, const union acpi_object **obj)
528 return adev ? acpi_data_get_property(&adev->data, name, type, obj) : -EINVAL;
530 EXPORT_SYMBOL_GPL(acpi_dev_get_property);
532 static const struct acpi_device_data *
533 acpi_device_data_of_node(const struct fwnode_handle *fwnode)
535 if (is_acpi_device_node(fwnode)) {
536 const struct acpi_device *adev = to_acpi_device_node(fwnode);
538 } else if (is_acpi_data_node(fwnode)) {
539 const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
546 * acpi_node_prop_get - return an ACPI property with given name.
547 * @fwnode: Firmware node to get the property from.
548 * @propname: Name of the property.
549 * @valptr: Location to store a pointer to the property value (if not %NULL).
551 int acpi_node_prop_get(const struct fwnode_handle *fwnode,
552 const char *propname, void **valptr)
554 return acpi_data_get_property(acpi_device_data_of_node(fwnode),
555 propname, ACPI_TYPE_ANY,
556 (const union acpi_object **)valptr);
560 * acpi_data_get_property_array - return an ACPI array property with given name
561 * @adev: ACPI data object to get the property from
562 * @name: Name of the property
563 * @type: Expected type of array elements
564 * @obj: Location to store a pointer to the property value (if not NULL)
566 * Look up an array property with @name and store a pointer to the resulting
567 * ACPI object at the location pointed to by @obj if found.
569 * Callers must not attempt to free the returned objects. Those objects will be
570 * freed by the ACPI core automatically during the removal of @data.
572 * Return: %0 if array property (package) with @name has been found (success),
573 * %-EINVAL if the arguments are invalid,
574 * %-EINVAL if the property doesn't exist,
575 * %-EPROTO if the property is not a package or the type of its elements
576 * doesn't match @type.
578 static int acpi_data_get_property_array(const struct acpi_device_data *data,
580 acpi_object_type type,
581 const union acpi_object **obj)
583 const union acpi_object *prop;
586 ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop);
590 if (type != ACPI_TYPE_ANY) {
591 /* Check that all elements are of correct type. */
592 for (i = 0; i < prop->package.count; i++)
593 if (prop->package.elements[i].type != type)
602 static struct fwnode_handle *
603 acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
604 const char *childname)
606 char name[ACPI_PATH_SEGMENT_LENGTH];
607 struct fwnode_handle *child;
608 struct acpi_buffer path;
611 path.length = sizeof(name);
614 fwnode_for_each_child_node(fwnode, child) {
615 if (is_acpi_data_node(child)) {
616 if (acpi_data_node_match(child, childname))
621 status = acpi_get_name(ACPI_HANDLE_FWNODE(child),
622 ACPI_SINGLE_NAME, &path);
623 if (ACPI_FAILURE(status))
626 if (!strncmp(name, childname, ACPI_NAMESEG_SIZE))
634 * __acpi_node_get_property_reference - returns handle to the referenced object
635 * @fwnode: Firmware node to get the property from
636 * @propname: Name of the property
637 * @index: Index of the reference to return
638 * @num_args: Maximum number of arguments after each reference
639 * @args: Location to store the returned reference with optional arguments
641 * Find property with @name, verifify that it is a package containing at least
642 * one object reference and if so, store the ACPI device object pointer to the
643 * target object in @args->adev. If the reference includes arguments, store
644 * them in the @args->args[] array.
646 * If there's more than one reference in the property value package, @index is
647 * used to select the one to return.
649 * It is possible to leave holes in the property value set like in the
662 * Calling this function with index %2 or index %3 return %-ENOENT. If the
663 * property does not contain any more values %-ENOENT is returned. The NULL
664 * entry must be single integer and preferably contain value %0.
666 * Return: %0 on success, negative error code on failure.
668 int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
669 const char *propname, size_t index, size_t num_args,
670 struct fwnode_reference_args *args)
672 const union acpi_object *element, *end;
673 const union acpi_object *obj;
674 const struct acpi_device_data *data;
675 struct acpi_device *device;
678 data = acpi_device_data_of_node(fwnode);
682 ret = acpi_data_get_property(data, propname, ACPI_TYPE_ANY, &obj);
684 return ret == -EINVAL ? -ENOENT : -EINVAL;
687 * The simplest case is when the value is a single reference. Just
688 * return that reference then.
690 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE) {
694 ret = acpi_bus_get_device(obj->reference.handle, &device);
696 return ret == -ENODEV ? -EINVAL : ret;
698 args->fwnode = acpi_fwnode_handle(device);
704 * If it is not a single reference, then it is a package of
705 * references followed by number of ints as follows:
707 * Package () { REF, INT, REF, INT, INT }
709 * The index argument is then used to determine which reference
710 * the caller wants (along with the arguments).
712 if (obj->type != ACPI_TYPE_PACKAGE)
714 if (index >= obj->package.count)
717 element = obj->package.elements;
718 end = element + obj->package.count;
720 while (element < end) {
723 if (element->type == ACPI_TYPE_LOCAL_REFERENCE) {
724 struct fwnode_handle *ref_fwnode;
726 ret = acpi_bus_get_device(element->reference.handle,
735 * Find the referred data extension node under the
736 * referred device node.
738 for (ref_fwnode = acpi_fwnode_handle(device);
739 element < end && element->type == ACPI_TYPE_STRING;
741 ref_fwnode = acpi_fwnode_get_named_child_node(
742 ref_fwnode, element->string.pointer);
747 /* assume following integer elements are all args */
748 for (i = 0; element + i < end && i < num_args; i++) {
749 int type = element[i].type;
751 if (type == ACPI_TYPE_INTEGER)
753 else if (type == ACPI_TYPE_LOCAL_REFERENCE)
759 if (nargs > NR_FWNODE_REFERENCE_ARGS)
763 args->fwnode = ref_fwnode;
765 for (i = 0; i < nargs; i++)
766 args->args[i] = element[i].integer.value;
772 } else if (element->type == ACPI_TYPE_INTEGER) {
785 EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);
787 static int acpi_data_prop_read_single(const struct acpi_device_data *data,
788 const char *propname,
789 enum dev_prop_type proptype, void *val)
791 const union acpi_object *obj;
797 if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64) {
798 ret = acpi_data_get_property(data, propname, ACPI_TYPE_INTEGER, &obj);
804 if (obj->integer.value > U8_MAX)
806 *(u8 *)val = obj->integer.value;
809 if (obj->integer.value > U16_MAX)
811 *(u16 *)val = obj->integer.value;
814 if (obj->integer.value > U32_MAX)
816 *(u32 *)val = obj->integer.value;
819 *(u64 *)val = obj->integer.value;
822 } else if (proptype == DEV_PROP_STRING) {
823 ret = acpi_data_get_property(data, propname, ACPI_TYPE_STRING, &obj);
827 *(char **)val = obj->string.pointer;
836 int acpi_dev_prop_read_single(struct acpi_device *adev, const char *propname,
837 enum dev_prop_type proptype, void *val)
844 ret = acpi_data_prop_read_single(&adev->data, propname, proptype, val);
845 if (ret < 0 || proptype != ACPI_TYPE_STRING)
850 static int acpi_copy_property_array_u8(const union acpi_object *items, u8 *val,
855 for (i = 0; i < nval; i++) {
856 if (items[i].type != ACPI_TYPE_INTEGER)
858 if (items[i].integer.value > U8_MAX)
861 val[i] = items[i].integer.value;
866 static int acpi_copy_property_array_u16(const union acpi_object *items,
867 u16 *val, size_t nval)
871 for (i = 0; i < nval; i++) {
872 if (items[i].type != ACPI_TYPE_INTEGER)
874 if (items[i].integer.value > U16_MAX)
877 val[i] = items[i].integer.value;
882 static int acpi_copy_property_array_u32(const union acpi_object *items,
883 u32 *val, size_t nval)
887 for (i = 0; i < nval; i++) {
888 if (items[i].type != ACPI_TYPE_INTEGER)
890 if (items[i].integer.value > U32_MAX)
893 val[i] = items[i].integer.value;
898 static int acpi_copy_property_array_u64(const union acpi_object *items,
899 u64 *val, size_t nval)
903 for (i = 0; i < nval; i++) {
904 if (items[i].type != ACPI_TYPE_INTEGER)
907 val[i] = items[i].integer.value;
912 static int acpi_copy_property_array_string(const union acpi_object *items,
913 char **val, size_t nval)
917 for (i = 0; i < nval; i++) {
918 if (items[i].type != ACPI_TYPE_STRING)
921 val[i] = items[i].string.pointer;
926 static int acpi_data_prop_read(const struct acpi_device_data *data,
927 const char *propname,
928 enum dev_prop_type proptype,
929 void *val, size_t nval)
931 const union acpi_object *obj;
932 const union acpi_object *items;
935 if (val && nval == 1) {
936 ret = acpi_data_prop_read_single(data, propname, proptype, val);
941 ret = acpi_data_get_property_array(data, propname, ACPI_TYPE_ANY, &obj);
946 return obj->package.count;
948 if (proptype != DEV_PROP_STRING && nval > obj->package.count)
953 items = obj->package.elements;
957 ret = acpi_copy_property_array_u8(items, (u8 *)val, nval);
960 ret = acpi_copy_property_array_u16(items, (u16 *)val, nval);
963 ret = acpi_copy_property_array_u32(items, (u32 *)val, nval);
966 ret = acpi_copy_property_array_u64(items, (u64 *)val, nval);
968 case DEV_PROP_STRING:
969 ret = acpi_copy_property_array_string(
971 min_t(u32, nval, obj->package.count));
980 int acpi_dev_prop_read(const struct acpi_device *adev, const char *propname,
981 enum dev_prop_type proptype, void *val, size_t nval)
983 return adev ? acpi_data_prop_read(&adev->data, propname, proptype, val, nval) : -EINVAL;
987 * acpi_node_prop_read - retrieve the value of an ACPI property with given name.
988 * @fwnode: Firmware node to get the property from.
989 * @propname: Name of the property.
990 * @proptype: Expected property type.
991 * @val: Location to store the property value (if not %NULL).
992 * @nval: Size of the array pointed to by @val.
994 * If @val is %NULL, return the number of array elements comprising the value
995 * of the property. Otherwise, read at most @nval values to the array at the
996 * location pointed to by @val.
998 int acpi_node_prop_read(const struct fwnode_handle *fwnode,
999 const char *propname, enum dev_prop_type proptype,
1000 void *val, size_t nval)
1002 return acpi_data_prop_read(acpi_device_data_of_node(fwnode),
1003 propname, proptype, val, nval);
1007 * acpi_get_next_subnode - Return the next child node handle for a fwnode
1008 * @fwnode: Firmware node to find the next child node for.
1009 * @child: Handle to one of the device's child nodes or a null handle.
1011 struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
1012 struct fwnode_handle *child)
1014 const struct acpi_device *adev = to_acpi_device_node(fwnode);
1015 const struct list_head *head;
1016 struct list_head *next;
1018 if (!child || is_acpi_device_node(child)) {
1019 struct acpi_device *child_adev;
1022 head = &adev->children;
1026 if (list_empty(head))
1030 adev = to_acpi_device_node(child);
1031 next = adev->node.next;
1036 child_adev = list_entry(next, struct acpi_device, node);
1038 child_adev = list_first_entry(head, struct acpi_device,
1041 return acpi_fwnode_handle(child_adev);
1045 if (!child || is_acpi_data_node(child)) {
1046 const struct acpi_data_node *data = to_acpi_data_node(fwnode);
1047 struct acpi_data_node *dn;
1050 * We can have a combination of device and data nodes, e.g. with
1051 * hierarchical _DSD properties. Make sure the adev pointer is
1052 * restored before going through data nodes, otherwise we will
1053 * be looking for data_nodes below the last device found instead
1054 * of the common fwnode shared by device_nodes and data_nodes.
1056 adev = to_acpi_device_node(fwnode);
1058 head = &adev->data.subnodes;
1060 head = &data->data.subnodes;
1064 if (list_empty(head))
1068 dn = to_acpi_data_node(child);
1069 next = dn->sibling.next;
1073 dn = list_entry(next, struct acpi_data_node, sibling);
1075 dn = list_first_entry(head, struct acpi_data_node, sibling);
1083 * acpi_node_get_parent - Return parent fwnode of this fwnode
1084 * @fwnode: Firmware node whose parent to get
1086 * Returns parent node of an ACPI device or data firmware node or %NULL if
1089 struct fwnode_handle *acpi_node_get_parent(const struct fwnode_handle *fwnode)
1091 if (is_acpi_data_node(fwnode)) {
1092 /* All data nodes have parent pointer so just return that */
1093 return to_acpi_data_node(fwnode)->parent;
1094 } else if (is_acpi_device_node(fwnode)) {
1095 acpi_handle handle, parent_handle;
1097 handle = to_acpi_device_node(fwnode)->handle;
1098 if (ACPI_SUCCESS(acpi_get_parent(handle, &parent_handle))) {
1099 struct acpi_device *adev;
1101 if (!acpi_bus_get_device(parent_handle, &adev))
1102 return acpi_fwnode_handle(adev);
1110 * Return true if the node is an ACPI graph node. Called on either ports
1113 static bool is_acpi_graph_node(struct fwnode_handle *fwnode,
1116 unsigned int len = strlen(str);
1119 if (!len || !is_acpi_data_node(fwnode))
1122 name = to_acpi_data_node(fwnode)->name;
1124 return (fwnode_property_present(fwnode, "reg") &&
1125 !strncmp(name, str, len) && name[len] == '@') ||
1126 fwnode_property_present(fwnode, str);
1130 * acpi_graph_get_next_endpoint - Get next endpoint ACPI firmware node
1131 * @fwnode: Pointer to the parent firmware node
1132 * @prev: Previous endpoint node or %NULL to get the first
1134 * Looks up next endpoint ACPI firmware node below a given @fwnode. Returns
1135 * %NULL if there is no next endpoint or in case of error. In case of success
1136 * the next endpoint is returned.
1138 static struct fwnode_handle *acpi_graph_get_next_endpoint(
1139 const struct fwnode_handle *fwnode, struct fwnode_handle *prev)
1141 struct fwnode_handle *port = NULL;
1142 struct fwnode_handle *endpoint;
1146 port = fwnode_get_next_child_node(fwnode, port);
1148 * The names of the port nodes begin with "port@"
1149 * followed by the number of the port node and they also
1150 * have a "reg" property that also has the number of the
1151 * port node. For compatibility reasons a node is also
1152 * recognised as a port node from the "port" property.
1154 if (is_acpi_graph_node(port, "port"))
1158 port = fwnode_get_parent(prev);
1164 endpoint = fwnode_get_next_child_node(port, prev);
1166 port = fwnode_get_next_child_node(fwnode, port);
1169 if (is_acpi_graph_node(port, "port"))
1170 endpoint = fwnode_get_next_child_node(port, NULL);
1174 * The names of the endpoint nodes begin with "endpoint@" followed by
1175 * the number of the endpoint node and they also have a "reg" property
1176 * that also has the number of the endpoint node. For compatibility
1177 * reasons a node is also recognised as an endpoint node from the
1178 * "endpoint" property.
1180 if (!is_acpi_graph_node(endpoint, "endpoint"))
1187 * acpi_graph_get_child_prop_value - Return a child with a given property value
1188 * @fwnode: device fwnode
1189 * @prop_name: The name of the property to look for
1190 * @val: the desired property value
1192 * Return the port node corresponding to a given port number. Returns
1193 * the child node on success, NULL otherwise.
1195 static struct fwnode_handle *acpi_graph_get_child_prop_value(
1196 const struct fwnode_handle *fwnode, const char *prop_name,
1199 struct fwnode_handle *child;
1201 fwnode_for_each_child_node(fwnode, child) {
1204 if (fwnode_property_read_u32(child, prop_name, &nr))
1216 * acpi_graph_get_remote_enpoint - Parses and returns remote end of an endpoint
1217 * @fwnode: Endpoint firmware node pointing to a remote device
1218 * @endpoint: Firmware node of remote endpoint is filled here if not %NULL
1220 * Returns the remote endpoint corresponding to @__fwnode. NULL on error.
1222 static struct fwnode_handle *
1223 acpi_graph_get_remote_endpoint(const struct fwnode_handle *__fwnode)
1225 struct fwnode_handle *fwnode;
1226 unsigned int port_nr, endpoint_nr;
1227 struct fwnode_reference_args args;
1230 memset(&args, 0, sizeof(args));
1231 ret = acpi_node_get_property_reference(__fwnode, "remote-endpoint", 0,
1236 /* Direct endpoint reference? */
1237 if (!is_acpi_device_node(args.fwnode))
1238 return args.nargs ? NULL : args.fwnode;
1241 * Always require two arguments with the reference: port and
1244 if (args.nargs != 2)
1247 fwnode = args.fwnode;
1248 port_nr = args.args[0];
1249 endpoint_nr = args.args[1];
1251 fwnode = acpi_graph_get_child_prop_value(fwnode, "port", port_nr);
1253 return acpi_graph_get_child_prop_value(fwnode, "endpoint", endpoint_nr);
1256 static bool acpi_fwnode_device_is_available(const struct fwnode_handle *fwnode)
1258 if (!is_acpi_device_node(fwnode))
1261 return acpi_device_is_present(to_acpi_device_node(fwnode));
1264 static bool acpi_fwnode_property_present(const struct fwnode_handle *fwnode,
1265 const char *propname)
1267 return !acpi_node_prop_get(fwnode, propname, NULL);
1271 acpi_fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
1272 const char *propname,
1273 unsigned int elem_size, void *val,
1276 enum dev_prop_type type;
1278 switch (elem_size) {
1283 type = DEV_PROP_U16;
1286 type = DEV_PROP_U32;
1289 type = DEV_PROP_U64;
1295 return acpi_node_prop_read(fwnode, propname, type, val, nval);
1299 acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
1300 const char *propname, const char **val,
1303 return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
1308 acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
1309 const char *prop, const char *nargs_prop,
1310 unsigned int args_count, unsigned int index,
1311 struct fwnode_reference_args *args)
1313 return __acpi_node_get_property_reference(fwnode, prop, index,
1317 static struct fwnode_handle *
1318 acpi_fwnode_get_parent(struct fwnode_handle *fwnode)
1320 return acpi_node_get_parent(fwnode);
1323 static int acpi_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
1324 struct fwnode_endpoint *endpoint)
1326 struct fwnode_handle *port_fwnode = fwnode_get_parent(fwnode);
1328 endpoint->local_fwnode = fwnode;
1330 if (fwnode_property_read_u32(port_fwnode, "reg", &endpoint->port))
1331 fwnode_property_read_u32(port_fwnode, "port", &endpoint->port);
1332 if (fwnode_property_read_u32(fwnode, "reg", &endpoint->id))
1333 fwnode_property_read_u32(fwnode, "endpoint", &endpoint->id);
1339 acpi_fwnode_device_get_match_data(const struct fwnode_handle *fwnode,
1340 const struct device *dev)
1342 return acpi_device_get_match_data(dev);
1345 #define DECLARE_ACPI_FWNODE_OPS(ops) \
1346 const struct fwnode_operations ops = { \
1347 .device_is_available = acpi_fwnode_device_is_available, \
1348 .device_get_match_data = acpi_fwnode_device_get_match_data, \
1349 .property_present = acpi_fwnode_property_present, \
1350 .property_read_int_array = \
1351 acpi_fwnode_property_read_int_array, \
1352 .property_read_string_array = \
1353 acpi_fwnode_property_read_string_array, \
1354 .get_parent = acpi_node_get_parent, \
1355 .get_next_child_node = acpi_get_next_subnode, \
1356 .get_named_child_node = acpi_fwnode_get_named_child_node, \
1357 .get_reference_args = acpi_fwnode_get_reference_args, \
1358 .graph_get_next_endpoint = \
1359 acpi_graph_get_next_endpoint, \
1360 .graph_get_remote_endpoint = \
1361 acpi_graph_get_remote_endpoint, \
1362 .graph_get_port_parent = acpi_fwnode_get_parent, \
1363 .graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint, \
1365 EXPORT_SYMBOL_GPL(ops)
1367 DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
1368 DECLARE_ACPI_FWNODE_OPS(acpi_data_fwnode_ops);
1369 const struct fwnode_operations acpi_static_fwnode_ops;
1371 bool is_acpi_device_node(const struct fwnode_handle *fwnode)
1373 return !IS_ERR_OR_NULL(fwnode) &&
1374 fwnode->ops == &acpi_device_fwnode_ops;
1376 EXPORT_SYMBOL(is_acpi_device_node);
1378 bool is_acpi_data_node(const struct fwnode_handle *fwnode)
1380 return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &acpi_data_fwnode_ops;
1382 EXPORT_SYMBOL(is_acpi_data_node);