1 /******************************************************************************
3 * Module Name: nsutils - Utilities for accessing ACPI namespace, accessing
4 * parents and siblings and Scope manipulation
6 *****************************************************************************/
9 * Copyright (C) 2000 - 2006, R. Byron Moore
10 * All rights reserved.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer,
17 * without modification.
18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19 * substantially similar to the "NO WARRANTY" disclaimer below
20 * ("Disclaimer") and any redistribution must be conditioned upon
21 * including a substantially similar Disclaimer requirement for further
22 * binary redistribution.
23 * 3. Neither the names of the above-listed copyright holders nor the names
24 * of any contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
27 * Alternatively, this software may be distributed under the terms of the
28 * GNU General Public License ("GPL") version 2 as published by the Free
29 * Software Foundation.
32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 * POSSIBILITY OF SUCH DAMAGES.
45 #include <acpi/acpi.h>
46 #include <acpi/acnamesp.h>
47 #include <acpi/amlcode.h>
48 #include <acpi/actables.h>
50 #define _COMPONENT ACPI_NAMESPACE
51 ACPI_MODULE_NAME("nsutils")
53 /* Local prototypes */
54 static u8 acpi_ns_valid_path_separator(char sep);
56 #ifdef ACPI_OBSOLETE_FUNCTIONS
57 acpi_name acpi_ns_find_parent_name(struct acpi_namespace_node *node_to_search);
60 /*******************************************************************************
62 * FUNCTION: acpi_ns_report_error
64 * PARAMETERS: module_name - Caller's module name (for error output)
65 * line_number - Caller's line number (for error output)
66 * internal_name - Name or path of the namespace node
67 * lookup_status - Exception code from NS lookup
71 * DESCRIPTION: Print warning message with full pathname
73 ******************************************************************************/
76 acpi_ns_report_error(char *module_name,
78 char *internal_name, acpi_status lookup_status)
84 acpi_os_printf("ACPI Error (%s-%04d): ", module_name, line_number);
86 if (lookup_status == AE_BAD_CHARACTER) {
88 /* There is a non-ascii character in the name */
90 ACPI_MOVE_32_TO_32(&bad_name, internal_name);
91 acpi_os_printf("[0x%4.4X] (NON-ASCII)", bad_name);
93 /* Convert path to external format */
95 status = acpi_ns_externalize_name(ACPI_UINT32_MAX,
96 internal_name, NULL, &name);
98 /* Print target name */
100 if (ACPI_SUCCESS(status)) {
101 acpi_os_printf("[%s]", name);
103 acpi_os_printf("[COULD NOT EXTERNALIZE NAME]");
111 acpi_os_printf(" Namespace lookup failure, %s\n",
112 acpi_format_exception(lookup_status));
115 /*******************************************************************************
117 * FUNCTION: acpi_ns_report_method_error
119 * PARAMETERS: module_name - Caller's module name (for error output)
120 * line_number - Caller's line number (for error output)
121 * Message - Error message to use on failure
122 * prefix_node - Prefix relative to the path
123 * Path - Path to the node (optional)
124 * method_status - Execution status
128 * DESCRIPTION: Print warning message with full pathname
130 ******************************************************************************/
133 acpi_ns_report_method_error(char *module_name,
136 struct acpi_namespace_node *prefix_node,
137 char *path, acpi_status method_status)
140 struct acpi_namespace_node *node = prefix_node;
142 acpi_os_printf("ACPI Error (%s-%04d): ", module_name, line_number);
146 acpi_ns_get_node(prefix_node, path, ACPI_NS_NO_UPSEARCH,
148 if (ACPI_FAILURE(status)) {
149 acpi_os_printf("[Could not get node by pathname]");
153 acpi_ns_print_node_pathname(node, message);
154 acpi_os_printf(", %s\n", acpi_format_exception(method_status));
157 /*******************************************************************************
159 * FUNCTION: acpi_ns_print_node_pathname
161 * PARAMETERS: Node - Object
162 * Message - Prefix message
164 * DESCRIPTION: Print an object's full namespace pathname
165 * Manages allocation/freeing of a pathname buffer
167 ******************************************************************************/
170 acpi_ns_print_node_pathname(struct acpi_namespace_node *node, char *message)
172 struct acpi_buffer buffer;
176 acpi_os_printf("[NULL NAME]");
180 /* Convert handle to full pathname and print it (with supplied message) */
182 buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
184 status = acpi_ns_handle_to_pathname(node, &buffer);
185 if (ACPI_SUCCESS(status)) {
187 acpi_os_printf("%s ", message);
190 acpi_os_printf("[%s] (Node %p)", (char *)buffer.pointer, node);
191 ACPI_FREE(buffer.pointer);
195 /*******************************************************************************
197 * FUNCTION: acpi_ns_valid_root_prefix
199 * PARAMETERS: Prefix - Character to be checked
201 * RETURN: TRUE if a valid prefix
203 * DESCRIPTION: Check if a character is a valid ACPI Root prefix
205 ******************************************************************************/
207 u8 acpi_ns_valid_root_prefix(char prefix)
210 return ((u8) (prefix == '\\'));
213 /*******************************************************************************
215 * FUNCTION: acpi_ns_valid_path_separator
217 * PARAMETERS: Sep - Character to be checked
219 * RETURN: TRUE if a valid path separator
221 * DESCRIPTION: Check if a character is a valid ACPI path separator
223 ******************************************************************************/
225 static u8 acpi_ns_valid_path_separator(char sep)
228 return ((u8) (sep == '.'));
231 /*******************************************************************************
233 * FUNCTION: acpi_ns_get_type
235 * PARAMETERS: Node - Parent Node to be examined
237 * RETURN: Type field from Node whose handle is passed
239 * DESCRIPTION: Return the type of a Namespace node
241 ******************************************************************************/
243 acpi_object_type acpi_ns_get_type(struct acpi_namespace_node * node)
245 ACPI_FUNCTION_TRACE(ns_get_type);
248 ACPI_WARNING((AE_INFO, "Null Node parameter"));
249 return_UINT32(ACPI_TYPE_ANY);
252 return_UINT32((acpi_object_type) node->type);
255 /*******************************************************************************
257 * FUNCTION: acpi_ns_local
259 * PARAMETERS: Type - A namespace object type
261 * RETURN: LOCAL if names must be found locally in objects of the
262 * passed type, 0 if enclosing scopes should be searched
264 * DESCRIPTION: Returns scope rule for the given object type.
266 ******************************************************************************/
268 u32 acpi_ns_local(acpi_object_type type)
270 ACPI_FUNCTION_TRACE(ns_local);
272 if (!acpi_ut_valid_object_type(type)) {
274 /* Type code out of range */
276 ACPI_WARNING((AE_INFO, "Invalid Object Type %X", type));
277 return_UINT32(ACPI_NS_NORMAL);
280 return_UINT32((u32) acpi_gbl_ns_properties[type] & ACPI_NS_LOCAL);
283 /*******************************************************************************
285 * FUNCTION: acpi_ns_get_internal_name_length
287 * PARAMETERS: Info - Info struct initialized with the
288 * external name pointer.
292 * DESCRIPTION: Calculate the length of the internal (AML) namestring
293 * corresponding to the external (ASL) namestring.
295 ******************************************************************************/
297 void acpi_ns_get_internal_name_length(struct acpi_namestring_info *info)
299 char *next_external_char;
302 ACPI_FUNCTION_ENTRY();
304 next_external_char = info->external_name;
305 info->num_carats = 0;
306 info->num_segments = 0;
307 info->fully_qualified = FALSE;
310 * For the internal name, the required length is 4 bytes per segment, plus
311 * 1 each for root_prefix, multi_name_prefix_op, segment count, trailing null
312 * (which is not really needed, but no there's harm in putting it there)
314 * strlen() + 1 covers the first name_seg, which has no path separator
316 if (acpi_ns_valid_root_prefix(next_external_char[0])) {
317 info->fully_qualified = TRUE;
318 next_external_char++;
321 * Handle Carat prefixes
323 while (*next_external_char == '^') {
325 next_external_char++;
330 * Determine the number of ACPI name "segments" by counting the number of
331 * path separators within the string. Start with one segment since the
332 * segment count is [(# separators) + 1], and zero separators is ok.
334 if (*next_external_char) {
335 info->num_segments = 1;
336 for (i = 0; next_external_char[i]; i++) {
337 if (acpi_ns_valid_path_separator(next_external_char[i])) {
338 info->num_segments++;
343 info->length = (ACPI_NAME_SIZE * info->num_segments) +
344 4 + info->num_carats;
346 info->next_external_char = next_external_char;
349 /*******************************************************************************
351 * FUNCTION: acpi_ns_build_internal_name
353 * PARAMETERS: Info - Info struct fully initialized
357 * DESCRIPTION: Construct the internal (AML) namestring
358 * corresponding to the external (ASL) namestring.
360 ******************************************************************************/
362 acpi_status acpi_ns_build_internal_name(struct acpi_namestring_info *info)
364 u32 num_segments = info->num_segments;
365 char *internal_name = info->internal_name;
366 char *external_name = info->next_external_char;
370 ACPI_FUNCTION_TRACE(ns_build_internal_name);
372 /* Setup the correct prefixes, counts, and pointers */
374 if (info->fully_qualified) {
375 internal_name[0] = '\\';
377 if (num_segments <= 1) {
378 result = &internal_name[1];
379 } else if (num_segments == 2) {
380 internal_name[1] = AML_DUAL_NAME_PREFIX;
381 result = &internal_name[2];
383 internal_name[1] = AML_MULTI_NAME_PREFIX_OP;
384 internal_name[2] = (char)num_segments;
385 result = &internal_name[3];
389 * Not fully qualified.
390 * Handle Carats first, then append the name segments
393 if (info->num_carats) {
394 for (i = 0; i < info->num_carats; i++) {
395 internal_name[i] = '^';
399 if (num_segments <= 1) {
400 result = &internal_name[i];
401 } else if (num_segments == 2) {
402 internal_name[i] = AML_DUAL_NAME_PREFIX;
403 result = &internal_name[(acpi_native_uint) (i + 1)];
405 internal_name[i] = AML_MULTI_NAME_PREFIX_OP;
406 internal_name[(acpi_native_uint) (i + 1)] =
408 result = &internal_name[(acpi_native_uint) (i + 2)];
412 /* Build the name (minus path separators) */
414 for (; num_segments; num_segments--) {
415 for (i = 0; i < ACPI_NAME_SIZE; i++) {
416 if (acpi_ns_valid_path_separator(*external_name) ||
417 (*external_name == 0)) {
419 /* Pad the segment with underscore(s) if segment is short */
423 /* Convert the character to uppercase and save it */
426 (char)ACPI_TOUPPER((int)*external_name);
431 /* Now we must have a path separator, or the pathname is bad */
433 if (!acpi_ns_valid_path_separator(*external_name) &&
434 (*external_name != 0)) {
435 return_ACPI_STATUS(AE_BAD_PARAMETER);
438 /* Move on the next segment */
441 result += ACPI_NAME_SIZE;
444 /* Terminate the string */
448 if (info->fully_qualified) {
449 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
450 "Returning [%p] (abs) \"\\%s\"\n",
451 internal_name, internal_name));
453 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Returning [%p] (rel) \"%s\"\n",
454 internal_name, internal_name));
457 return_ACPI_STATUS(AE_OK);
460 /*******************************************************************************
462 * FUNCTION: acpi_ns_internalize_name
464 * PARAMETERS: *external_name - External representation of name
465 * **Converted Name - Where to return the resulting
466 * internal represention of the name
470 * DESCRIPTION: Convert an external representation (e.g. "\_PR_.CPU0")
471 * to internal form (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
473 *******************************************************************************/
475 acpi_status acpi_ns_internalize_name(char *external_name, char **converted_name)
478 struct acpi_namestring_info info;
481 ACPI_FUNCTION_TRACE(ns_internalize_name);
483 if ((!external_name) || (*external_name == 0) || (!converted_name)) {
484 return_ACPI_STATUS(AE_BAD_PARAMETER);
487 /* Get the length of the new internal name */
489 info.external_name = external_name;
490 acpi_ns_get_internal_name_length(&info);
492 /* We need a segment to store the internal name */
494 internal_name = ACPI_ALLOCATE_ZEROED(info.length);
495 if (!internal_name) {
496 return_ACPI_STATUS(AE_NO_MEMORY);
501 info.internal_name = internal_name;
502 status = acpi_ns_build_internal_name(&info);
503 if (ACPI_FAILURE(status)) {
504 ACPI_FREE(internal_name);
505 return_ACPI_STATUS(status);
508 *converted_name = internal_name;
509 return_ACPI_STATUS(AE_OK);
512 /*******************************************************************************
514 * FUNCTION: acpi_ns_externalize_name
516 * PARAMETERS: internal_name_length - Lenth of the internal name below
517 * internal_name - Internal representation of name
518 * converted_name_length - Where the length is returned
519 * converted_name - Where the resulting external name
524 * DESCRIPTION: Convert internal name (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
525 * to its external (printable) form (e.g. "\_PR_.CPU0")
527 ******************************************************************************/
530 acpi_ns_externalize_name(u32 internal_name_length,
532 u32 * converted_name_length, char **converted_name)
534 acpi_native_uint names_index = 0;
535 acpi_native_uint num_segments = 0;
536 acpi_native_uint required_length;
537 acpi_native_uint prefix_length = 0;
538 acpi_native_uint i = 0;
539 acpi_native_uint j = 0;
541 ACPI_FUNCTION_TRACE(ns_externalize_name);
543 if (!internal_name_length || !internal_name || !converted_name) {
544 return_ACPI_STATUS(AE_BAD_PARAMETER);
548 * Check for a prefix (one '\' | one or more '^').
550 switch (internal_name[0]) {
556 for (i = 0; i < internal_name_length; i++) {
557 if (internal_name[i] == '^') {
558 prefix_length = i + 1;
564 if (i == internal_name_length) {
575 * Check for object names. Note that there could be 0-255 of these
578 if (prefix_length < internal_name_length) {
579 switch (internal_name[prefix_length]) {
580 case AML_MULTI_NAME_PREFIX_OP:
582 /* <count> 4-byte names */
584 names_index = prefix_length + 2;
585 num_segments = (acpi_native_uint) (u8)
586 internal_name[(acpi_native_uint)
587 (prefix_length + 1)];
590 case AML_DUAL_NAME_PREFIX:
592 /* Two 4-byte names */
594 names_index = prefix_length + 1;
608 /* one 4-byte name */
610 names_index = prefix_length;
617 * Calculate the length of converted_name, which equals the length
618 * of the prefix, length of all object names, length of any required
619 * punctuation ('.') between object names, plus the NULL terminator.
621 required_length = prefix_length + (4 * num_segments) +
622 ((num_segments > 0) ? (num_segments - 1) : 0) + 1;
625 * Check to see if we're still in bounds. If not, there's a problem
626 * with internal_name (invalid format).
628 if (required_length > internal_name_length) {
629 ACPI_ERROR((AE_INFO, "Invalid internal name"));
630 return_ACPI_STATUS(AE_BAD_PATHNAME);
634 * Build converted_name
636 *converted_name = ACPI_ALLOCATE_ZEROED(required_length);
637 if (!(*converted_name)) {
638 return_ACPI_STATUS(AE_NO_MEMORY);
643 for (i = 0; i < prefix_length; i++) {
644 (*converted_name)[j++] = internal_name[i];
647 if (num_segments > 0) {
648 for (i = 0; i < num_segments; i++) {
650 (*converted_name)[j++] = '.';
653 (*converted_name)[j++] = internal_name[names_index++];
654 (*converted_name)[j++] = internal_name[names_index++];
655 (*converted_name)[j++] = internal_name[names_index++];
656 (*converted_name)[j++] = internal_name[names_index++];
660 if (converted_name_length) {
661 *converted_name_length = (u32) required_length;
664 return_ACPI_STATUS(AE_OK);
667 /*******************************************************************************
669 * FUNCTION: acpi_ns_map_handle_to_node
671 * PARAMETERS: Handle - Handle to be converted to an Node
673 * RETURN: A Name table entry pointer
675 * DESCRIPTION: Convert a namespace handle to a real Node
677 * Note: Real integer handles would allow for more verification
678 * and keep all pointers within this subsystem - however this introduces
679 * more (and perhaps unnecessary) overhead.
681 ******************************************************************************/
683 struct acpi_namespace_node *acpi_ns_map_handle_to_node(acpi_handle handle)
686 ACPI_FUNCTION_ENTRY();
689 * Simple implementation
691 if ((!handle) || (handle == ACPI_ROOT_OBJECT)) {
692 return (acpi_gbl_root_node);
695 /* We can at least attempt to verify the handle */
697 if (ACPI_GET_DESCRIPTOR_TYPE(handle) != ACPI_DESC_TYPE_NAMED) {
701 return (ACPI_CAST_PTR(struct acpi_namespace_node, handle));
704 /*******************************************************************************
706 * FUNCTION: acpi_ns_convert_entry_to_handle
708 * PARAMETERS: Node - Node to be converted to a Handle
710 * RETURN: A user handle
712 * DESCRIPTION: Convert a real Node to a namespace handle
714 ******************************************************************************/
716 acpi_handle acpi_ns_convert_entry_to_handle(struct acpi_namespace_node *node)
720 * Simple implementation for now;
722 return ((acpi_handle) node);
724 /* Example future implementation ---------------------
731 if (Node == acpi_gbl_root_node)
733 return (ACPI_ROOT_OBJECT);
736 return ((acpi_handle) Node);
737 ------------------------------------------------------*/
740 /*******************************************************************************
742 * FUNCTION: acpi_ns_terminate
748 * DESCRIPTION: free memory allocated for namespace and ACPI table storage.
750 ******************************************************************************/
752 void acpi_ns_terminate(void)
754 union acpi_operand_object *obj_desc;
756 ACPI_FUNCTION_TRACE(ns_terminate);
759 * 1) Free the entire namespace -- all nodes and objects
761 * Delete all object descriptors attached to namepsace nodes
763 acpi_ns_delete_namespace_subtree(acpi_gbl_root_node);
765 /* Detach any objects attached to the root */
767 obj_desc = acpi_ns_get_attached_object(acpi_gbl_root_node);
769 acpi_ns_detach_object(acpi_gbl_root_node);
772 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Namespace freed\n"));
775 * 2) Now we can delete the ACPI tables
777 acpi_tb_delete_all_tables();
778 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "ACPI Tables freed\n"));
783 /*******************************************************************************
785 * FUNCTION: acpi_ns_opens_scope
787 * PARAMETERS: Type - A valid namespace type
789 * RETURN: NEWSCOPE if the passed type "opens a name scope" according
790 * to the ACPI specification, else 0
792 ******************************************************************************/
794 u32 acpi_ns_opens_scope(acpi_object_type type)
796 ACPI_FUNCTION_TRACE_STR(ns_opens_scope, acpi_ut_get_type_name(type));
798 if (!acpi_ut_valid_object_type(type)) {
800 /* type code out of range */
802 ACPI_WARNING((AE_INFO, "Invalid Object Type %X", type));
803 return_UINT32(ACPI_NS_NORMAL);
806 return_UINT32(((u32) acpi_gbl_ns_properties[type]) & ACPI_NS_NEWSCOPE);
809 /*******************************************************************************
811 * FUNCTION: acpi_ns_get_node
813 * PARAMETERS: *Pathname - Name to be found, in external (ASL) format. The
814 * \ (backslash) and ^ (carat) prefixes, and the
815 * . (period) to separate segments are supported.
816 * prefix_node - Root of subtree to be searched, or NS_ALL for the
817 * root of the name space. If Name is fully
818 * qualified (first s8 is '\'), the passed value
819 * of Scope will not be accessed.
820 * Flags - Used to indicate whether to perform upsearch or
822 * return_node - Where the Node is returned
824 * DESCRIPTION: Look up a name relative to a given scope and return the
825 * corresponding Node. NOTE: Scope can be null.
827 * MUTEX: Locks namespace
829 ******************************************************************************/
832 acpi_ns_get_node(struct acpi_namespace_node *prefix_node,
834 u32 flags, struct acpi_namespace_node **return_node)
836 union acpi_generic_state scope_info;
840 ACPI_FUNCTION_TRACE_PTR(ns_get_node, pathname);
843 *return_node = prefix_node;
845 *return_node = acpi_gbl_root_node;
847 return_ACPI_STATUS(AE_OK);
850 /* Convert path to internal representation */
852 status = acpi_ns_internalize_name(pathname, &internal_path);
853 if (ACPI_FAILURE(status)) {
854 return_ACPI_STATUS(status);
857 /* Must lock namespace during lookup */
859 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
860 if (ACPI_FAILURE(status)) {
864 /* Setup lookup scope (search starting point) */
866 scope_info.scope.node = prefix_node;
868 /* Lookup the name in the namespace */
870 status = acpi_ns_lookup(&scope_info, internal_path, ACPI_TYPE_ANY,
872 (flags | ACPI_NS_DONT_OPEN_SCOPE), NULL,
874 if (ACPI_FAILURE(status)) {
875 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s, %s\n",
876 pathname, acpi_format_exception(status)));
879 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
882 ACPI_FREE(internal_path);
883 return_ACPI_STATUS(status);
886 /*******************************************************************************
888 * FUNCTION: acpi_ns_get_parent_node
890 * PARAMETERS: Node - Current table entry
892 * RETURN: Parent entry of the given entry
894 * DESCRIPTION: Obtain the parent entry for a given entry in the namespace.
896 ******************************************************************************/
898 struct acpi_namespace_node *acpi_ns_get_parent_node(struct acpi_namespace_node
901 ACPI_FUNCTION_ENTRY();
908 * Walk to the end of this peer list. The last entry is marked with a flag
909 * and the peer pointer is really a pointer back to the parent. This saves
910 * putting a parent back pointer in each and every named object!
912 while (!(node->flags & ANOBJ_END_OF_PEER_LIST)) {
919 /*******************************************************************************
921 * FUNCTION: acpi_ns_get_next_valid_node
923 * PARAMETERS: Node - Current table entry
925 * RETURN: Next valid Node in the linked node list. NULL if no more valid
928 * DESCRIPTION: Find the next valid node within a name table.
929 * Useful for implementing NULL-end-of-list loops.
931 ******************************************************************************/
933 struct acpi_namespace_node *acpi_ns_get_next_valid_node(struct
938 /* If we are at the end of this peer list, return NULL */
940 if (node->flags & ANOBJ_END_OF_PEER_LIST) {
944 /* Otherwise just return the next peer */
949 #ifdef ACPI_OBSOLETE_FUNCTIONS
950 /*******************************************************************************
952 * FUNCTION: acpi_ns_find_parent_name
954 * PARAMETERS: *child_node - Named Obj whose name is to be found
956 * RETURN: The ACPI name
958 * DESCRIPTION: Search for the given obj in its parent scope and return the
959 * name segment, or "????" if the parent name can't be found
960 * (which "should not happen").
962 ******************************************************************************/
964 acpi_name acpi_ns_find_parent_name(struct acpi_namespace_node * child_node)
966 struct acpi_namespace_node *parent_node;
968 ACPI_FUNCTION_TRACE(ns_find_parent_name);
972 /* Valid entry. Get the parent Node */
974 parent_node = acpi_ns_get_parent_node(child_node);
976 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
977 "Parent of %p [%4.4s] is %p [%4.4s]\n",
979 acpi_ut_get_node_name(child_node),
981 acpi_ut_get_node_name(parent_node)));
983 if (parent_node->name.integer) {
984 return_VALUE((acpi_name) parent_node->name.
989 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
990 "Unable to find parent of %p (%4.4s)\n",
992 acpi_ut_get_node_name(child_node)));
995 return_VALUE(ACPI_UNKNOWN_NAME);