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Diffstat (limited to 'drivers/acpi/namespace/nswalk.c')
-rw-r--r--drivers/acpi/namespace/nswalk.c289
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diff --git a/drivers/acpi/namespace/nswalk.c b/drivers/acpi/namespace/nswalk.c
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+++ b/drivers/acpi/namespace/nswalk.c
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+/******************************************************************************
+ *
+ * Module Name: nswalk - Functions for walking the ACPI namespace
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2005, 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);
+}
+
+