1 // SPDX-License-Identifier: GPL-2.0-only
3 * ACPI device specific properties support.
5 * Copyright (C) 2014, Intel Corporation
8 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
9 * Darren Hart <dvhart@linux.intel.com>
10 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
13 #include <linux/acpi.h>
14 #include <linux/device.h>
15 #include <linux/export.h>
19 static int acpi_data_get_property_array(const struct acpi_device_data *data,
21 acpi_object_type type,
22 const union acpi_object **obj);
25 * The GUIDs here are made equivalent to each other in order to avoid extra
26 * complexity in the properties handling code, with the caveat that the
27 * kernel will accept certain combinations of GUID and properties that are
28 * not defined without a warning. For instance if any of the properties
29 * from different GUID appear in a property list of another, it will be
30 * accepted by the kernel. Firmware validation tools should catch these.
32 static const guid_t prp_guids[] = {
33 /* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
34 GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c,
35 0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01),
36 /* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */
37 GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3,
38 0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4),
39 /* External facing port GUID: efcc06cc-73ac-4bc3-bff0-76143807c389 */
40 GUID_INIT(0xefcc06cc, 0x73ac, 0x4bc3,
41 0xbf, 0xf0, 0x76, 0x14, 0x38, 0x07, 0xc3, 0x89),
44 /* ACPI _DSD data subnodes GUID: dbb8e3e6-5886-4ba6-8795-1319f52a966b */
45 static const guid_t ads_guid =
46 GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
47 0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b);
49 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
50 const union acpi_object *desc,
51 struct acpi_device_data *data,
52 struct fwnode_handle *parent);
53 static bool acpi_extract_properties(const union acpi_object *desc,
54 struct acpi_device_data *data);
56 static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
58 const union acpi_object *link,
59 struct list_head *list,
60 struct fwnode_handle *parent)
62 struct acpi_data_node *dn;
65 dn = kzalloc(sizeof(*dn), GFP_KERNEL);
69 dn->name = link->package.elements[0].string.pointer;
70 dn->fwnode.ops = &acpi_data_fwnode_ops;
72 INIT_LIST_HEAD(&dn->data.properties);
73 INIT_LIST_HEAD(&dn->data.subnodes);
75 result = acpi_extract_properties(desc, &dn->data);
82 * The scope for the subnode object lookup is the one of the
83 * namespace node (device) containing the object that has
84 * returned the package. That is, it's the scope of that
87 status = acpi_get_parent(handle, &scope);
88 if (ACPI_SUCCESS(status)
89 && acpi_enumerate_nondev_subnodes(scope, desc, &dn->data,
92 } else if (acpi_enumerate_nondev_subnodes(NULL, desc, &dn->data,
99 dn->data.pointer = desc;
100 list_add_tail(&dn->sibling, list);
105 acpi_handle_debug(handle, "Invalid properties/subnodes data, skipping\n");
109 static bool acpi_nondev_subnode_data_ok(acpi_handle handle,
110 const union acpi_object *link,
111 struct list_head *list,
112 struct fwnode_handle *parent)
114 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
117 status = acpi_evaluate_object_typed(handle, NULL, NULL, &buf,
119 if (ACPI_FAILURE(status))
122 if (acpi_nondev_subnode_extract(buf.pointer, handle, link, list,
126 ACPI_FREE(buf.pointer);
130 static bool acpi_nondev_subnode_ok(acpi_handle scope,
131 const union acpi_object *link,
132 struct list_head *list,
133 struct fwnode_handle *parent)
141 status = acpi_get_handle(scope, link->package.elements[1].string.pointer,
143 if (ACPI_FAILURE(status))
146 return acpi_nondev_subnode_data_ok(handle, link, list, parent);
149 static int acpi_add_nondev_subnodes(acpi_handle scope,
150 const union acpi_object *links,
151 struct list_head *list,
152 struct fwnode_handle *parent)
157 for (i = 0; i < links->package.count; i++) {
158 const union acpi_object *link, *desc;
162 link = &links->package.elements[i];
163 /* Only two elements allowed. */
164 if (link->package.count != 2)
167 /* The first one must be a string. */
168 if (link->package.elements[0].type != ACPI_TYPE_STRING)
171 /* The second one may be a string, a reference or a package. */
172 switch (link->package.elements[1].type) {
173 case ACPI_TYPE_STRING:
174 result = acpi_nondev_subnode_ok(scope, link, list,
177 case ACPI_TYPE_LOCAL_REFERENCE:
178 handle = link->package.elements[1].reference.handle;
179 result = acpi_nondev_subnode_data_ok(handle, link, list,
182 case ACPI_TYPE_PACKAGE:
183 desc = &link->package.elements[1];
184 result = acpi_nondev_subnode_extract(desc, NULL, link,
197 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
198 const union acpi_object *desc,
199 struct acpi_device_data *data,
200 struct fwnode_handle *parent)
204 /* Look for the ACPI data subnodes GUID. */
205 for (i = 0; i < desc->package.count; i += 2) {
206 const union acpi_object *guid, *links;
208 guid = &desc->package.elements[i];
209 links = &desc->package.elements[i + 1];
212 * The first element must be a GUID and the second one must be
215 if (guid->type != ACPI_TYPE_BUFFER ||
216 guid->buffer.length != 16 ||
217 links->type != ACPI_TYPE_PACKAGE)
220 if (!guid_equal((guid_t *)guid->buffer.pointer, &ads_guid))
223 return acpi_add_nondev_subnodes(scope, links, &data->subnodes,
230 static bool acpi_property_value_ok(const union acpi_object *value)
235 * The value must be an integer, a string, a reference, or a package
236 * whose every element must be an integer, a string, or a reference.
238 switch (value->type) {
239 case ACPI_TYPE_INTEGER:
240 case ACPI_TYPE_STRING:
241 case ACPI_TYPE_LOCAL_REFERENCE:
244 case ACPI_TYPE_PACKAGE:
245 for (j = 0; j < value->package.count; j++)
246 switch (value->package.elements[j].type) {
247 case ACPI_TYPE_INTEGER:
248 case ACPI_TYPE_STRING:
249 case ACPI_TYPE_LOCAL_REFERENCE:
261 static bool acpi_properties_format_valid(const union acpi_object *properties)
265 for (i = 0; i < properties->package.count; i++) {
266 const union acpi_object *property;
268 property = &properties->package.elements[i];
270 * Only two elements allowed, the first one must be a string and
271 * the second one has to satisfy certain conditions.
273 if (property->package.count != 2
274 || property->package.elements[0].type != ACPI_TYPE_STRING
275 || !acpi_property_value_ok(&property->package.elements[1]))
281 static void acpi_init_of_compatible(struct acpi_device *adev)
283 const union acpi_object *of_compatible;
286 ret = acpi_data_get_property_array(&adev->data, "compatible",
287 ACPI_TYPE_STRING, &of_compatible);
289 ret = acpi_dev_get_property(adev, "compatible",
290 ACPI_TYPE_STRING, &of_compatible);
293 && adev->parent->flags.of_compatible_ok)
299 adev->data.of_compatible = of_compatible;
302 adev->flags.of_compatible_ok = 1;
305 static bool acpi_is_property_guid(const guid_t *guid)
309 for (i = 0; i < ARRAY_SIZE(prp_guids); i++) {
310 if (guid_equal(guid, &prp_guids[i]))
317 struct acpi_device_properties *
318 acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
319 const union acpi_object *properties)
321 struct acpi_device_properties *props;
323 props = kzalloc(sizeof(*props), GFP_KERNEL);
325 INIT_LIST_HEAD(&props->list);
327 props->properties = properties;
328 list_add_tail(&props->list, &data->properties);
334 static bool acpi_extract_properties(const union acpi_object *desc,
335 struct acpi_device_data *data)
339 if (desc->package.count % 2)
342 /* Look for the device properties GUID. */
343 for (i = 0; i < desc->package.count; i += 2) {
344 const union acpi_object *guid, *properties;
346 guid = &desc->package.elements[i];
347 properties = &desc->package.elements[i + 1];
350 * The first element must be a GUID and the second one must be
353 if (guid->type != ACPI_TYPE_BUFFER ||
354 guid->buffer.length != 16 ||
355 properties->type != ACPI_TYPE_PACKAGE)
358 if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
362 * We found the matching GUID. Now validate the format of the
363 * package immediately following it.
365 if (!acpi_properties_format_valid(properties))
368 acpi_data_add_props(data, (const guid_t *)guid->buffer.pointer,
372 return !list_empty(&data->properties);
375 void acpi_init_properties(struct acpi_device *adev)
377 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
378 struct acpi_hardware_id *hwid;
380 bool acpi_of = false;
382 INIT_LIST_HEAD(&adev->data.properties);
383 INIT_LIST_HEAD(&adev->data.subnodes);
389 * Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
390 * Device Tree compatible properties for this device.
392 list_for_each_entry(hwid, &adev->pnp.ids, list) {
393 if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
399 status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
401 if (ACPI_FAILURE(status))
404 if (acpi_extract_properties(buf.pointer, &adev->data)) {
405 adev->data.pointer = buf.pointer;
407 acpi_init_of_compatible(adev);
409 if (acpi_enumerate_nondev_subnodes(adev->handle, buf.pointer,
410 &adev->data, acpi_fwnode_handle(adev)))
411 adev->data.pointer = buf.pointer;
413 if (!adev->data.pointer) {
414 acpi_handle_debug(adev->handle, "Invalid _DSD data, skipping\n");
415 ACPI_FREE(buf.pointer);
419 if (acpi_of && !adev->flags.of_compatible_ok)
420 acpi_handle_info(adev->handle,
421 ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n");
423 if (!adev->data.pointer)
424 acpi_extract_apple_properties(adev);
427 static void acpi_destroy_nondev_subnodes(struct list_head *list)
429 struct acpi_data_node *dn, *next;
431 if (list_empty(list))
434 list_for_each_entry_safe_reverse(dn, next, list, sibling) {
435 acpi_destroy_nondev_subnodes(&dn->data.subnodes);
436 wait_for_completion(&dn->kobj_done);
437 list_del(&dn->sibling);
438 ACPI_FREE((void *)dn->data.pointer);
443 void acpi_free_properties(struct acpi_device *adev)
445 struct acpi_device_properties *props, *tmp;
447 acpi_destroy_nondev_subnodes(&adev->data.subnodes);
448 ACPI_FREE((void *)adev->data.pointer);
449 adev->data.of_compatible = NULL;
450 adev->data.pointer = NULL;
451 list_for_each_entry_safe(props, tmp, &adev->data.properties, list) {
452 list_del(&props->list);
458 * acpi_data_get_property - return an ACPI property with given name
459 * @data: ACPI device deta object to get the property from
460 * @name: Name of the property
461 * @type: Expected property type
462 * @obj: Location to store the property value (if not %NULL)
464 * Look up a property with @name and store a pointer to the resulting ACPI
465 * object at the location pointed to by @obj if found.
467 * Callers must not attempt to free the returned objects. These objects will be
468 * freed by the ACPI core automatically during the removal of @data.
470 * Return: %0 if property with @name has been found (success),
471 * %-EINVAL if the arguments are invalid,
472 * %-EINVAL if the property doesn't exist,
473 * %-EPROTO if the property value type doesn't match @type.
475 static int acpi_data_get_property(const struct acpi_device_data *data,
476 const char *name, acpi_object_type type,
477 const union acpi_object **obj)
479 const struct acpi_device_properties *props;
484 if (!data->pointer || list_empty(&data->properties))
487 list_for_each_entry(props, &data->properties, list) {
488 const union acpi_object *properties;
491 properties = props->properties;
492 for (i = 0; i < properties->package.count; i++) {
493 const union acpi_object *propname, *propvalue;
494 const union acpi_object *property;
496 property = &properties->package.elements[i];
498 propname = &property->package.elements[0];
499 propvalue = &property->package.elements[1];
501 if (!strcmp(name, propname->string.pointer)) {
502 if (type != ACPI_TYPE_ANY &&
503 propvalue->type != type)
516 * acpi_dev_get_property - return an ACPI property with given name.
517 * @adev: ACPI device to get the property from.
518 * @name: Name of the property.
519 * @type: Expected property type.
520 * @obj: Location to store the property value (if not %NULL).
522 int acpi_dev_get_property(const struct acpi_device *adev, const char *name,
523 acpi_object_type type, const union acpi_object **obj)
525 return adev ? acpi_data_get_property(&adev->data, name, type, obj) : -EINVAL;
527 EXPORT_SYMBOL_GPL(acpi_dev_get_property);
529 static const struct acpi_device_data *
530 acpi_device_data_of_node(const struct fwnode_handle *fwnode)
532 if (is_acpi_device_node(fwnode)) {
533 const struct acpi_device *adev = to_acpi_device_node(fwnode);
535 } else if (is_acpi_data_node(fwnode)) {
536 const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
543 * acpi_node_prop_get - return an ACPI property with given name.
544 * @fwnode: Firmware node to get the property from.
545 * @propname: Name of the property.
546 * @valptr: Location to store a pointer to the property value (if not %NULL).
548 int acpi_node_prop_get(const struct fwnode_handle *fwnode,
549 const char *propname, void **valptr)
551 return acpi_data_get_property(acpi_device_data_of_node(fwnode),
552 propname, ACPI_TYPE_ANY,
553 (const union acpi_object **)valptr);
557 * acpi_data_get_property_array - return an ACPI array property with given name
558 * @adev: ACPI data object to get the property from
559 * @name: Name of the property
560 * @type: Expected type of array elements
561 * @obj: Location to store a pointer to the property value (if not NULL)
563 * Look up an array property with @name and store a pointer to the resulting
564 * ACPI object at the location pointed to by @obj if found.
566 * Callers must not attempt to free the returned objects. Those objects will be
567 * freed by the ACPI core automatically during the removal of @data.
569 * Return: %0 if array property (package) with @name has been found (success),
570 * %-EINVAL if the arguments are invalid,
571 * %-EINVAL if the property doesn't exist,
572 * %-EPROTO if the property is not a package or the type of its elements
573 * doesn't match @type.
575 static int acpi_data_get_property_array(const struct acpi_device_data *data,
577 acpi_object_type type,
578 const union acpi_object **obj)
580 const union acpi_object *prop;
583 ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop);
587 if (type != ACPI_TYPE_ANY) {
588 /* Check that all elements are of correct type. */
589 for (i = 0; i < prop->package.count; i++)
590 if (prop->package.elements[i].type != type)
599 static struct fwnode_handle *
600 acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
601 const char *childname)
603 char name[ACPI_PATH_SEGMENT_LENGTH];
604 struct fwnode_handle *child;
605 struct acpi_buffer path;
608 path.length = sizeof(name);
611 fwnode_for_each_child_node(fwnode, child) {
612 if (is_acpi_data_node(child)) {
613 if (acpi_data_node_match(child, childname))
618 status = acpi_get_name(ACPI_HANDLE_FWNODE(child),
619 ACPI_SINGLE_NAME, &path);
620 if (ACPI_FAILURE(status))
623 if (!strncmp(name, childname, ACPI_NAMESEG_SIZE))
631 * __acpi_node_get_property_reference - returns handle to the referenced object
632 * @fwnode: Firmware node to get the property from
633 * @propname: Name of the property
634 * @index: Index of the reference to return
635 * @num_args: Maximum number of arguments after each reference
636 * @args: Location to store the returned reference with optional arguments
638 * Find property with @name, verifify that it is a package containing at least
639 * one object reference and if so, store the ACPI device object pointer to the
640 * target object in @args->adev. If the reference includes arguments, store
641 * them in the @args->args[] array.
643 * If there's more than one reference in the property value package, @index is
644 * used to select the one to return.
646 * It is possible to leave holes in the property value set like in the
659 * Calling this function with index %2 or index %3 return %-ENOENT. If the
660 * property does not contain any more values %-ENOENT is returned. The NULL
661 * entry must be single integer and preferably contain value %0.
663 * Return: %0 on success, negative error code on failure.
665 int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
666 const char *propname, size_t index, size_t num_args,
667 struct fwnode_reference_args *args)
669 const union acpi_object *element, *end;
670 const union acpi_object *obj;
671 const struct acpi_device_data *data;
672 struct acpi_device *device;
675 data = acpi_device_data_of_node(fwnode);
679 ret = acpi_data_get_property(data, propname, ACPI_TYPE_ANY, &obj);
681 return ret == -EINVAL ? -ENOENT : -EINVAL;
684 * The simplest case is when the value is a single reference. Just
685 * return that reference then.
687 if (obj->type == ACPI_TYPE_LOCAL_REFERENCE) {
691 ret = acpi_bus_get_device(obj->reference.handle, &device);
693 return ret == -ENODEV ? -EINVAL : ret;
695 args->fwnode = acpi_fwnode_handle(device);
701 * If it is not a single reference, then it is a package of
702 * references followed by number of ints as follows:
704 * Package () { REF, INT, REF, INT, INT }
706 * The index argument is then used to determine which reference
707 * the caller wants (along with the arguments).
709 if (obj->type != ACPI_TYPE_PACKAGE)
711 if (index >= obj->package.count)
714 element = obj->package.elements;
715 end = element + obj->package.count;
717 while (element < end) {
720 if (element->type == ACPI_TYPE_LOCAL_REFERENCE) {
721 struct fwnode_handle *ref_fwnode;
723 ret = acpi_bus_get_device(element->reference.handle,
732 * Find the referred data extension node under the
733 * referred device node.
735 for (ref_fwnode = acpi_fwnode_handle(device);
736 element < end && element->type == ACPI_TYPE_STRING;
738 ref_fwnode = acpi_fwnode_get_named_child_node(
739 ref_fwnode, element->string.pointer);
744 /* assume following integer elements are all args */
745 for (i = 0; element + i < end && i < num_args; i++) {
746 int type = element[i].type;
748 if (type == ACPI_TYPE_INTEGER)
750 else if (type == ACPI_TYPE_LOCAL_REFERENCE)
756 if (nargs > NR_FWNODE_REFERENCE_ARGS)
760 args->fwnode = ref_fwnode;
762 for (i = 0; i < nargs; i++)
763 args->args[i] = element[i].integer.value;
769 } else if (element->type == ACPI_TYPE_INTEGER) {
782 EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);
784 static int acpi_data_prop_read_single(const struct acpi_device_data *data,
785 const char *propname,
786 enum dev_prop_type proptype, void *val)
788 const union acpi_object *obj;
794 if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64) {
795 ret = acpi_data_get_property(data, propname, ACPI_TYPE_INTEGER, &obj);
801 if (obj->integer.value > U8_MAX)
803 *(u8 *)val = obj->integer.value;
806 if (obj->integer.value > U16_MAX)
808 *(u16 *)val = obj->integer.value;
811 if (obj->integer.value > U32_MAX)
813 *(u32 *)val = obj->integer.value;
816 *(u64 *)val = obj->integer.value;
819 } else if (proptype == DEV_PROP_STRING) {
820 ret = acpi_data_get_property(data, propname, ACPI_TYPE_STRING, &obj);
824 *(char **)val = obj->string.pointer;
833 int acpi_dev_prop_read_single(struct acpi_device *adev, const char *propname,
834 enum dev_prop_type proptype, void *val)
841 ret = acpi_data_prop_read_single(&adev->data, propname, proptype, val);
842 if (ret < 0 || proptype != ACPI_TYPE_STRING)
847 static int acpi_copy_property_array_u8(const union acpi_object *items, u8 *val,
852 for (i = 0; i < nval; i++) {
853 if (items[i].type != ACPI_TYPE_INTEGER)
855 if (items[i].integer.value > U8_MAX)
858 val[i] = items[i].integer.value;
863 static int acpi_copy_property_array_u16(const union acpi_object *items,
864 u16 *val, size_t nval)
868 for (i = 0; i < nval; i++) {
869 if (items[i].type != ACPI_TYPE_INTEGER)
871 if (items[i].integer.value > U16_MAX)
874 val[i] = items[i].integer.value;
879 static int acpi_copy_property_array_u32(const union acpi_object *items,
880 u32 *val, size_t nval)
884 for (i = 0; i < nval; i++) {
885 if (items[i].type != ACPI_TYPE_INTEGER)
887 if (items[i].integer.value > U32_MAX)
890 val[i] = items[i].integer.value;
895 static int acpi_copy_property_array_u64(const union acpi_object *items,
896 u64 *val, size_t nval)
900 for (i = 0; i < nval; i++) {
901 if (items[i].type != ACPI_TYPE_INTEGER)
904 val[i] = items[i].integer.value;
909 static int acpi_copy_property_array_string(const union acpi_object *items,
910 char **val, size_t nval)
914 for (i = 0; i < nval; i++) {
915 if (items[i].type != ACPI_TYPE_STRING)
918 val[i] = items[i].string.pointer;
923 static int acpi_data_prop_read(const struct acpi_device_data *data,
924 const char *propname,
925 enum dev_prop_type proptype,
926 void *val, size_t nval)
928 const union acpi_object *obj;
929 const union acpi_object *items;
932 if (val && nval == 1) {
933 ret = acpi_data_prop_read_single(data, propname, proptype, val);
938 ret = acpi_data_get_property_array(data, propname, ACPI_TYPE_ANY, &obj);
943 return obj->package.count;
945 if (proptype != DEV_PROP_STRING && nval > obj->package.count)
950 items = obj->package.elements;
954 ret = acpi_copy_property_array_u8(items, (u8 *)val, nval);
957 ret = acpi_copy_property_array_u16(items, (u16 *)val, nval);
960 ret = acpi_copy_property_array_u32(items, (u32 *)val, nval);
963 ret = acpi_copy_property_array_u64(items, (u64 *)val, nval);
965 case DEV_PROP_STRING:
966 ret = acpi_copy_property_array_string(
968 min_t(u32, nval, obj->package.count));
977 int acpi_dev_prop_read(const struct acpi_device *adev, const char *propname,
978 enum dev_prop_type proptype, void *val, size_t nval)
980 return adev ? acpi_data_prop_read(&adev->data, propname, proptype, val, nval) : -EINVAL;
984 * acpi_node_prop_read - retrieve the value of an ACPI property with given name.
985 * @fwnode: Firmware node to get the property from.
986 * @propname: Name of the property.
987 * @proptype: Expected property type.
988 * @val: Location to store the property value (if not %NULL).
989 * @nval: Size of the array pointed to by @val.
991 * If @val is %NULL, return the number of array elements comprising the value
992 * of the property. Otherwise, read at most @nval values to the array at the
993 * location pointed to by @val.
995 int acpi_node_prop_read(const struct fwnode_handle *fwnode,
996 const char *propname, enum dev_prop_type proptype,
997 void *val, size_t nval)
999 return acpi_data_prop_read(acpi_device_data_of_node(fwnode),
1000 propname, proptype, val, nval);
1004 * acpi_get_next_subnode - Return the next child node handle for a fwnode
1005 * @fwnode: Firmware node to find the next child node for.
1006 * @child: Handle to one of the device's child nodes or a null handle.
1008 struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
1009 struct fwnode_handle *child)
1011 const struct acpi_device *adev = to_acpi_device_node(fwnode);
1012 const struct list_head *head;
1013 struct list_head *next;
1015 if (!child || is_acpi_device_node(child)) {
1016 struct acpi_device *child_adev;
1019 head = &adev->children;
1023 if (list_empty(head))
1027 adev = to_acpi_device_node(child);
1028 next = adev->node.next;
1033 child_adev = list_entry(next, struct acpi_device, node);
1035 child_adev = list_first_entry(head, struct acpi_device,
1038 return acpi_fwnode_handle(child_adev);
1042 if (!child || is_acpi_data_node(child)) {
1043 const struct acpi_data_node *data = to_acpi_data_node(fwnode);
1044 struct acpi_data_node *dn;
1047 * We can have a combination of device and data nodes, e.g. with
1048 * hierarchical _DSD properties. Make sure the adev pointer is
1049 * restored before going through data nodes, otherwise we will
1050 * be looking for data_nodes below the last device found instead
1051 * of the common fwnode shared by device_nodes and data_nodes.
1053 adev = to_acpi_device_node(fwnode);
1055 head = &adev->data.subnodes;
1057 head = &data->data.subnodes;
1061 if (list_empty(head))
1065 dn = to_acpi_data_node(child);
1066 next = dn->sibling.next;
1070 dn = list_entry(next, struct acpi_data_node, sibling);
1072 dn = list_first_entry(head, struct acpi_data_node, sibling);
1080 * acpi_node_get_parent - Return parent fwnode of this fwnode
1081 * @fwnode: Firmware node whose parent to get
1083 * Returns parent node of an ACPI device or data firmware node or %NULL if
1086 struct fwnode_handle *acpi_node_get_parent(const struct fwnode_handle *fwnode)
1088 if (is_acpi_data_node(fwnode)) {
1089 /* All data nodes have parent pointer so just return that */
1090 return to_acpi_data_node(fwnode)->parent;
1091 } else if (is_acpi_device_node(fwnode)) {
1092 acpi_handle handle, parent_handle;
1094 handle = to_acpi_device_node(fwnode)->handle;
1095 if (ACPI_SUCCESS(acpi_get_parent(handle, &parent_handle))) {
1096 struct acpi_device *adev;
1098 if (!acpi_bus_get_device(parent_handle, &adev))
1099 return acpi_fwnode_handle(adev);
1107 * Return true if the node is an ACPI graph node. Called on either ports
1110 static bool is_acpi_graph_node(struct fwnode_handle *fwnode,
1113 unsigned int len = strlen(str);
1116 if (!len || !is_acpi_data_node(fwnode))
1119 name = to_acpi_data_node(fwnode)->name;
1121 return (fwnode_property_present(fwnode, "reg") &&
1122 !strncmp(name, str, len) && name[len] == '@') ||
1123 fwnode_property_present(fwnode, str);
1127 * acpi_graph_get_next_endpoint - Get next endpoint ACPI firmware node
1128 * @fwnode: Pointer to the parent firmware node
1129 * @prev: Previous endpoint node or %NULL to get the first
1131 * Looks up next endpoint ACPI firmware node below a given @fwnode. Returns
1132 * %NULL if there is no next endpoint or in case of error. In case of success
1133 * the next endpoint is returned.
1135 static struct fwnode_handle *acpi_graph_get_next_endpoint(
1136 const struct fwnode_handle *fwnode, struct fwnode_handle *prev)
1138 struct fwnode_handle *port = NULL;
1139 struct fwnode_handle *endpoint;
1143 port = fwnode_get_next_child_node(fwnode, port);
1145 * The names of the port nodes begin with "port@"
1146 * followed by the number of the port node and they also
1147 * have a "reg" property that also has the number of the
1148 * port node. For compatibility reasons a node is also
1149 * recognised as a port node from the "port" property.
1151 if (is_acpi_graph_node(port, "port"))
1155 port = fwnode_get_parent(prev);
1161 endpoint = fwnode_get_next_child_node(port, prev);
1163 port = fwnode_get_next_child_node(fwnode, port);
1166 if (is_acpi_graph_node(port, "port"))
1167 endpoint = fwnode_get_next_child_node(port, NULL);
1171 * The names of the endpoint nodes begin with "endpoint@" followed by
1172 * the number of the endpoint node and they also have a "reg" property
1173 * that also has the number of the endpoint node. For compatibility
1174 * reasons a node is also recognised as an endpoint node from the
1175 * "endpoint" property.
1177 if (!is_acpi_graph_node(endpoint, "endpoint"))
1184 * acpi_graph_get_child_prop_value - Return a child with a given property value
1185 * @fwnode: device fwnode
1186 * @prop_name: The name of the property to look for
1187 * @val: the desired property value
1189 * Return the port node corresponding to a given port number. Returns
1190 * the child node on success, NULL otherwise.
1192 static struct fwnode_handle *acpi_graph_get_child_prop_value(
1193 const struct fwnode_handle *fwnode, const char *prop_name,
1196 struct fwnode_handle *child;
1198 fwnode_for_each_child_node(fwnode, child) {
1201 if (fwnode_property_read_u32(child, prop_name, &nr))
1213 * acpi_graph_get_remote_enpoint - Parses and returns remote end of an endpoint
1214 * @fwnode: Endpoint firmware node pointing to a remote device
1215 * @endpoint: Firmware node of remote endpoint is filled here if not %NULL
1217 * Returns the remote endpoint corresponding to @__fwnode. NULL on error.
1219 static struct fwnode_handle *
1220 acpi_graph_get_remote_endpoint(const struct fwnode_handle *__fwnode)
1222 struct fwnode_handle *fwnode;
1223 unsigned int port_nr, endpoint_nr;
1224 struct fwnode_reference_args args;
1227 memset(&args, 0, sizeof(args));
1228 ret = acpi_node_get_property_reference(__fwnode, "remote-endpoint", 0,
1233 /* Direct endpoint reference? */
1234 if (!is_acpi_device_node(args.fwnode))
1235 return args.nargs ? NULL : args.fwnode;
1238 * Always require two arguments with the reference: port and
1241 if (args.nargs != 2)
1244 fwnode = args.fwnode;
1245 port_nr = args.args[0];
1246 endpoint_nr = args.args[1];
1248 fwnode = acpi_graph_get_child_prop_value(fwnode, "port", port_nr);
1250 return acpi_graph_get_child_prop_value(fwnode, "endpoint", endpoint_nr);
1253 static bool acpi_fwnode_device_is_available(const struct fwnode_handle *fwnode)
1255 if (!is_acpi_device_node(fwnode))
1258 return acpi_device_is_present(to_acpi_device_node(fwnode));
1261 static bool acpi_fwnode_property_present(const struct fwnode_handle *fwnode,
1262 const char *propname)
1264 return !acpi_node_prop_get(fwnode, propname, NULL);
1268 acpi_fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
1269 const char *propname,
1270 unsigned int elem_size, void *val,
1273 enum dev_prop_type type;
1275 switch (elem_size) {
1280 type = DEV_PROP_U16;
1283 type = DEV_PROP_U32;
1286 type = DEV_PROP_U64;
1292 return acpi_node_prop_read(fwnode, propname, type, val, nval);
1296 acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
1297 const char *propname, const char **val,
1300 return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
1305 acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
1306 const char *prop, const char *nargs_prop,
1307 unsigned int args_count, unsigned int index,
1308 struct fwnode_reference_args *args)
1310 return __acpi_node_get_property_reference(fwnode, prop, index,
1314 static struct fwnode_handle *
1315 acpi_fwnode_get_parent(struct fwnode_handle *fwnode)
1317 return acpi_node_get_parent(fwnode);
1320 static int acpi_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
1321 struct fwnode_endpoint *endpoint)
1323 struct fwnode_handle *port_fwnode = fwnode_get_parent(fwnode);
1325 endpoint->local_fwnode = fwnode;
1327 if (fwnode_property_read_u32(port_fwnode, "reg", &endpoint->port))
1328 fwnode_property_read_u32(port_fwnode, "port", &endpoint->port);
1329 if (fwnode_property_read_u32(fwnode, "reg", &endpoint->id))
1330 fwnode_property_read_u32(fwnode, "endpoint", &endpoint->id);
1336 acpi_fwnode_device_get_match_data(const struct fwnode_handle *fwnode,
1337 const struct device *dev)
1339 return acpi_device_get_match_data(dev);
1342 #define DECLARE_ACPI_FWNODE_OPS(ops) \
1343 const struct fwnode_operations ops = { \
1344 .device_is_available = acpi_fwnode_device_is_available, \
1345 .device_get_match_data = acpi_fwnode_device_get_match_data, \
1346 .property_present = acpi_fwnode_property_present, \
1347 .property_read_int_array = \
1348 acpi_fwnode_property_read_int_array, \
1349 .property_read_string_array = \
1350 acpi_fwnode_property_read_string_array, \
1351 .get_parent = acpi_node_get_parent, \
1352 .get_next_child_node = acpi_get_next_subnode, \
1353 .get_named_child_node = acpi_fwnode_get_named_child_node, \
1354 .get_reference_args = acpi_fwnode_get_reference_args, \
1355 .graph_get_next_endpoint = \
1356 acpi_graph_get_next_endpoint, \
1357 .graph_get_remote_endpoint = \
1358 acpi_graph_get_remote_endpoint, \
1359 .graph_get_port_parent = acpi_fwnode_get_parent, \
1360 .graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint, \
1362 EXPORT_SYMBOL_GPL(ops)
1364 DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
1365 DECLARE_ACPI_FWNODE_OPS(acpi_data_fwnode_ops);
1366 const struct fwnode_operations acpi_static_fwnode_ops;
1368 bool is_acpi_device_node(const struct fwnode_handle *fwnode)
1370 return !IS_ERR_OR_NULL(fwnode) &&
1371 fwnode->ops == &acpi_device_fwnode_ops;
1373 EXPORT_SYMBOL(is_acpi_device_node);
1375 bool is_acpi_data_node(const struct fwnode_handle *fwnode)
1377 return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &acpi_data_fwnode_ops;
1379 EXPORT_SYMBOL(is_acpi_data_node);