| /****************************************************************************** | |
| * | |
| * Module Name: nswalk - Functions for walking the ACPI namespace | |
| * | |
| *****************************************************************************/ | |
| /* | |
| * Copyright (C) 2000 - 2006, R. Byron Moore | |
| * All rights reserved. | |
| * | |
| * Redistribution and use in source and binary forms, with or without | |
| * modification, are permitted provided that the following conditions | |
| * are met: | |
| * 1. Redistributions of source code must retain the above copyright | |
| * notice, this list of conditions, and the following disclaimer, | |
| * without modification. | |
| * 2. Redistributions in binary form must reproduce at minimum a disclaimer | |
| * substantially similar to the "NO WARRANTY" disclaimer below | |
| * ("Disclaimer") and any redistribution must be conditioned upon | |
| * including a substantially similar Disclaimer requirement for further | |
| * binary redistribution. | |
| * 3. Neither the names of the above-listed copyright holders nor the names | |
| * of any contributors may be used to endorse or promote products derived | |
| * from this software without specific prior written permission. | |
| * | |
| * Alternatively, this software may be distributed under the terms of the | |
| * GNU General Public License ("GPL") version 2 as published by the Free | |
| * Software Foundation. | |
| * | |
| * NO WARRANTY | |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR | |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | |
| * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, | |
| * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING | |
| * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
| * POSSIBILITY OF SUCH DAMAGES. | |
| */ | |
| #include <acpi/acpi.h> | |
| #include <acpi/acnamesp.h> | |
| #define _COMPONENT ACPI_NAMESPACE | |
| ACPI_MODULE_NAME("nswalk") | |
| /******************************************************************************* | |
| * | |
| * FUNCTION: acpi_ns_get_next_node | |
| * | |
| * PARAMETERS: Type - Type of node to be searched for | |
| * parent_node - Parent node whose children we are | |
| * getting | |
| * child_node - Previous child that was found. | |
| * The NEXT child will be returned | |
| * | |
| * RETURN: struct acpi_namespace_node - Pointer to the NEXT child or NULL if | |
| * none is found. | |
| * | |
| * DESCRIPTION: Return the next peer node within the namespace. If Handle | |
| * is valid, Scope is ignored. Otherwise, the first node | |
| * within Scope is returned. | |
| * | |
| ******************************************************************************/ | |
| struct acpi_namespace_node *acpi_ns_get_next_node(acpi_object_type type, | |
| struct acpi_namespace_node | |
| *parent_node, | |
| struct acpi_namespace_node | |
| *child_node) | |
| { | |
| struct acpi_namespace_node *next_node = NULL; | |
| ACPI_FUNCTION_ENTRY(); | |
| if (!child_node) { | |
| /* It's really the parent's _scope_ that we want */ | |
| if (parent_node->child) { | |
| next_node = parent_node->child; | |
| } | |
| } | |
| else { | |
| /* Start search at the NEXT node */ | |
| next_node = acpi_ns_get_next_valid_node(child_node); | |
| } | |
| /* If any type is OK, we are done */ | |
| if (type == ACPI_TYPE_ANY) { | |
| /* next_node is NULL if we are at the end-of-list */ | |
| return (next_node); | |
| } | |
| /* Must search for the node -- but within this scope only */ | |
| while (next_node) { | |
| /* If type matches, we are done */ | |
| if (next_node->type == type) { | |
| return (next_node); | |
| } | |
| /* Otherwise, move on to the next node */ | |
| next_node = acpi_ns_get_next_valid_node(next_node); | |
| } | |
| /* Not found */ | |
| return (NULL); | |
| } | |
| /******************************************************************************* | |
| * | |
| * FUNCTION: acpi_ns_walk_namespace | |
| * | |
| * PARAMETERS: Type - acpi_object_type to search for | |
| * start_node - Handle in namespace where search begins | |
| * max_depth - Depth to which search is to reach | |
| * unlock_before_callback- Whether to unlock the NS before invoking | |
| * the callback routine | |
| * user_function - Called when an object of "Type" is found | |
| * Context - Passed to user function | |
| * return_value - from the user_function if terminated early. | |
| * Otherwise, returns NULL. | |
| * RETURNS: Status | |
| * | |
| * DESCRIPTION: Performs a modified depth-first walk of the namespace tree, | |
| * starting (and ending) at the node specified by start_handle. | |
| * The user_function is called whenever a node that matches | |
| * the type parameter is found. If the user function returns | |
| * a non-zero value, the search is terminated immediately and this | |
| * value is returned to the caller. | |
| * | |
| * The point of this procedure is to provide a generic namespace | |
| * walk routine that can be called from multiple places to | |
| * provide multiple services; the User Function can be tailored | |
| * to each task, whether it is a print function, a compare | |
| * function, etc. | |
| * | |
| ******************************************************************************/ | |
| acpi_status | |
| acpi_ns_walk_namespace(acpi_object_type type, | |
| acpi_handle start_node, | |
| u32 max_depth, | |
| u8 unlock_before_callback, | |
| acpi_walk_callback user_function, | |
| void *context, void **return_value) | |
| { | |
| acpi_status status; | |
| acpi_status mutex_status; | |
| struct acpi_namespace_node *child_node; | |
| struct acpi_namespace_node *parent_node; | |
| acpi_object_type child_type; | |
| u32 level; | |
| ACPI_FUNCTION_TRACE(ns_walk_namespace); | |
| /* Special case for the namespace Root Node */ | |
| if (start_node == ACPI_ROOT_OBJECT) { | |
| start_node = acpi_gbl_root_node; | |
| } | |
| /* Null child means "get first node" */ | |
| parent_node = start_node; | |
| child_node = NULL; | |
| child_type = ACPI_TYPE_ANY; | |
| level = 1; | |
| /* | |
| * Traverse the tree of nodes until we bubble back up to where we | |
| * started. When Level is zero, the loop is done because we have | |
| * bubbled up to (and passed) the original parent handle (start_entry) | |
| */ | |
| while (level > 0) { | |
| /* Get the next node in this scope. Null if not found */ | |
| status = AE_OK; | |
| child_node = | |
| acpi_ns_get_next_node(ACPI_TYPE_ANY, parent_node, | |
| child_node); | |
| if (child_node) { | |
| /* | |
| * Found node, Get the type if we are not | |
| * searching for ANY | |
| */ | |
| if (type != ACPI_TYPE_ANY) { | |
| child_type = child_node->type; | |
| } | |
| if (child_type == type) { | |
| /* | |
| * Found a matching node, invoke the user | |
| * callback function | |
| */ | |
| if (unlock_before_callback) { | |
| mutex_status = | |
| acpi_ut_release_mutex | |
| (ACPI_MTX_NAMESPACE); | |
| if (ACPI_FAILURE(mutex_status)) { | |
| return_ACPI_STATUS | |
| (mutex_status); | |
| } | |
| } | |
| status = user_function(child_node, level, | |
| context, return_value); | |
| if (unlock_before_callback) { | |
| mutex_status = | |
| acpi_ut_acquire_mutex | |
| (ACPI_MTX_NAMESPACE); | |
| if (ACPI_FAILURE(mutex_status)) { | |
| return_ACPI_STATUS | |
| (mutex_status); | |
| } | |
| } | |
| switch (status) { | |
| case AE_OK: | |
| case AE_CTRL_DEPTH: | |
| /* Just keep going */ | |
| break; | |
| case AE_CTRL_TERMINATE: | |
| /* Exit now, with OK status */ | |
| return_ACPI_STATUS(AE_OK); | |
| default: | |
| /* All others are valid exceptions */ | |
| return_ACPI_STATUS(status); | |
| } | |
| } | |
| /* | |
| * Depth first search: | |
| * Attempt to go down another level in the namespace | |
| * if we are allowed to. Don't go any further if we | |
| * have reached the caller specified maximum depth | |
| * or if the user function has specified that the | |
| * maximum depth has been reached. | |
| */ | |
| if ((level < max_depth) && (status != AE_CTRL_DEPTH)) { | |
| if (acpi_ns_get_next_node | |
| (ACPI_TYPE_ANY, child_node, NULL)) { | |
| /* | |
| * There is at least one child of this | |
| * node, visit the onde | |
| */ | |
| level++; | |
| parent_node = child_node; | |
| child_node = NULL; | |
| } | |
| } | |
| } else { | |
| /* | |
| * No more children of this node (acpi_ns_get_next_node | |
| * failed), go back upwards in the namespace tree to | |
| * the node's parent. | |
| */ | |
| level--; | |
| child_node = parent_node; | |
| parent_node = acpi_ns_get_parent_node(parent_node); | |
| } | |
| } | |
| /* Complete walk, not terminated by user function */ | |
| return_ACPI_STATUS(AE_OK); | |
| } |