1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
4  * Module Name: nswalk - Functions for walking the ACPI namespace
6  * Copyright (C) 2000 - 2022, Intel Corp.
21  * PARAMETERS:  parent_node         - Parent node whose children we are
23  *              child_node          - Previous child that was found.
26  * RETURN:      struct acpi_namespace_node - Pointer to the NEXT child or NULL if
45 		return (parent_node->child);  in acpi_ns_get_next_node()
50 	return (child_node->peer);  in acpi_ns_get_next_node()
57  * PARAMETERS:  type                - Type of node to be searched for
58  *              parent_node         - Parent node whose children we are
60  *              child_node          - Previous child that was found.
63  * RETURN:      struct acpi_namespace_node - Pointer to the NEXT child or NULL if
91 		/* next_node is NULL if we are at the end-of-list */  in acpi_ns_get_next_node_typed()
96 	/* Must search for the node -- but within this scope only */  in acpi_ns_get_next_node_typed()
102 		if (next_node->type == type) {  in acpi_ns_get_next_node_typed()
108 		next_node = next_node->peer;  in acpi_ns_get_next_node_typed()
120  * PARAMETERS:  type                - acpi_object_type to search for
121  *              start_node          - Handle in namespace where search begins
122  *              max_depth           - Depth to which search is to reach
123  *              flags               - Whether to unlock the NS before invoking
125  *              descending_callback - Called during tree descent
127  *              ascending_callback  - Called during tree ascent
129  *              context             - Passed to user function(s) above
130  *              return_value        - from the user_function if terminated
134  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
138  *              a non-zero value, the search is terminated immediately and
163 	u32 level;  in acpi_ns_walk_namespace()  local
182 	level = 1;  in acpi_ns_walk_namespace()
186 	 * started. When Level is zero, the loop is done because we have  in acpi_ns_walk_namespace()
189 	while (level > 0 && child_node) {  in acpi_ns_walk_namespace()
195 			child_type = child_node->type;  in acpi_ns_walk_namespace()
202 		 * the execution of the user function (if the namespace is  in acpi_ns_walk_namespace()
203 		 * unlocked before invocation of the user function.) Only the  in acpi_ns_walk_namespace()
206 		if ((child_node->flags & ANOBJ_TEMPORARY) &&  in acpi_ns_walk_namespace()
215 			 * Found a matching node, invoke the user callback function.  in acpi_ns_walk_namespace()
227 			 * Invoke the user function, either descending, ascending,  in acpi_ns_walk_namespace()
234 								level, context,  in acpi_ns_walk_namespace()
241 							       level, context,  in acpi_ns_walk_namespace()
276 		 * Depth first search: Attempt to go down another level in the  in acpi_ns_walk_namespace()
278 		 * reached the caller specified maximum depth or if the user  in acpi_ns_walk_namespace()
282 		    (level < max_depth) && (status != AE_CTRL_DEPTH)) {  in acpi_ns_walk_namespace()
283 			if (child_node->child) {  in acpi_ns_walk_namespace()
287 				level++;  in acpi_ns_walk_namespace()
295 		/* No more children, re-visit this node */  in acpi_ns_walk_namespace()
309 		/* No peers, re-visit parent */  in acpi_ns_walk_namespace()
316 			level--;  in acpi_ns_walk_namespace()
318 			parent_node = parent_node->parent;  in acpi_ns_walk_namespace()
324 	/* Complete walk, not terminated by user function */  in acpi_ns_walk_namespace()