/******************************************************************************
   *
   * Module Name: exresnte - AML Interpreter object resolution
   *
   *****************************************************************************/
  
  /*

   * Copyright (C) 2000 - 2008, Intel Corp.

   * 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 "accommon.h"
  #include "acdispat.h"
  #include "acinterp.h"
  #include "acnamesp.h"

  #define _COMPONENT          ACPI_EXECUTER

  ACPI_MODULE_NAME("exresnte")

  
  /*******************************************************************************
   *
   * FUNCTION:    acpi_ex_resolve_node_to_value
   *
   * PARAMETERS:  object_ptr      - Pointer to a location that contains
   *                                a pointer to a NS node, and will receive a
   *                                pointer to the resolved object.
   *              walk_state      - Current state.  Valid only if executing AML
   *                                code.  NULL if simply resolving an object
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Resolve a Namespace node to a valued object
   *
   * Note: for some of the data types, the pointer attached to the Node
   * can be either a pointer to an actual internal object or a pointer into the
   * AML stream itself.  These types are currently:
   *
   *      ACPI_TYPE_INTEGER
   *      ACPI_TYPE_STRING
   *      ACPI_TYPE_BUFFER
   *      ACPI_TYPE_MUTEX
   *      ACPI_TYPE_PACKAGE
   *
   ******************************************************************************/

  acpi_status

  acpi_ex_resolve_node_to_value(struct acpi_namespace_node **object_ptr,
  			      struct acpi_walk_state *walk_state)

  {

  	acpi_status status = AE_OK;
  	union acpi_operand_object *source_desc;
  	union acpi_operand_object *obj_desc = NULL;
  	struct acpi_namespace_node *node;
  	acpi_object_type entry_type;

  	ACPI_FUNCTION_TRACE(ex_resolve_node_to_value);

  
  	/*
  	 * The stack pointer points to a struct acpi_namespace_node (Node).  Get the
  	 * object that is attached to the Node.
  	 */

  	node = *object_ptr;
  	source_desc = acpi_ns_get_attached_object(node);
  	entry_type = acpi_ns_get_type((acpi_handle) node);

  	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Entry=%p SourceDesc=%p [%s]
  ",

  			  node, source_desc,
  			  acpi_ut_get_type_name(entry_type)));

  
  	if ((entry_type == ACPI_TYPE_LOCAL_ALIAS) ||

  	    (entry_type == ACPI_TYPE_LOCAL_METHOD_ALIAS)) {

  		/* There is always exactly one level of indirection */

  		node = ACPI_CAST_PTR(struct acpi_namespace_node, node->object);
  		source_desc = acpi_ns_get_attached_object(node);
  		entry_type = acpi_ns_get_type((acpi_handle) node);

  		*object_ptr = node;
  	}
  
  	/*
  	 * Several object types require no further processing:

  	 * 1) Device/Thermal objects don't have a "real" subobject, return the Node

  	 * 2) Method locals and arguments have a pseudo-Node

  	 * 3) 10/2007: Added method type to assist with Package construction.

  	 */

  	if ((entry_type == ACPI_TYPE_DEVICE) ||
  	    (entry_type == ACPI_TYPE_THERMAL) ||

  	    (entry_type == ACPI_TYPE_METHOD) ||

  	    (node->flags & (ANOBJ_METHOD_ARG | ANOBJ_METHOD_LOCAL))) {
  		return_ACPI_STATUS(AE_OK);

  	}
  
  	if (!source_desc) {

  		ACPI_ERROR((AE_INFO, "No object attached to node %p", node));

  		return_ACPI_STATUS(AE_AML_NO_OPERAND);

  	}
  
  	/*
  	 * Action is based on the type of the Node, which indicates the type
  	 * of the attached object or pointer
  	 */
  	switch (entry_type) {
  	case ACPI_TYPE_PACKAGE:

  		if (source_desc->common.type != ACPI_TYPE_PACKAGE) {

  			ACPI_ERROR((AE_INFO, "Object not a Package, type %s",
  				    acpi_ut_get_object_type_name(source_desc)));

  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);

  		}

  		status = acpi_ds_get_package_arguments(source_desc);
  		if (ACPI_SUCCESS(status)) {

  			/* Return an additional reference to the object */
  
  			obj_desc = source_desc;

  			acpi_ut_add_reference(obj_desc);

  		}
  		break;

  	case ACPI_TYPE_BUFFER:

  		if (source_desc->common.type != ACPI_TYPE_BUFFER) {

  			ACPI_ERROR((AE_INFO, "Object not a Buffer, type %s",
  				    acpi_ut_get_object_type_name(source_desc)));

  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);

  		}

  		status = acpi_ds_get_buffer_arguments(source_desc);
  		if (ACPI_SUCCESS(status)) {

  			/* Return an additional reference to the object */
  
  			obj_desc = source_desc;

  			acpi_ut_add_reference(obj_desc);

  		}
  		break;

  	case ACPI_TYPE_STRING:

  		if (source_desc->common.type != ACPI_TYPE_STRING) {

  			ACPI_ERROR((AE_INFO, "Object not a String, type %s",
  				    acpi_ut_get_object_type_name(source_desc)));

  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);

  		}
  
  		/* Return an additional reference to the object */
  
  		obj_desc = source_desc;

  		acpi_ut_add_reference(obj_desc);

  		break;

  	case ACPI_TYPE_INTEGER:

  		if (source_desc->common.type != ACPI_TYPE_INTEGER) {

  			ACPI_ERROR((AE_INFO, "Object not a Integer, type %s",
  				    acpi_ut_get_object_type_name(source_desc)));

  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);

  		}
  
  		/* Return an additional reference to the object */
  
  		obj_desc = source_desc;

  		acpi_ut_add_reference(obj_desc);

  		break;

  	case ACPI_TYPE_BUFFER_FIELD:
  	case ACPI_TYPE_LOCAL_REGION_FIELD:
  	case ACPI_TYPE_LOCAL_BANK_FIELD:
  	case ACPI_TYPE_LOCAL_INDEX_FIELD:

  		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,

  				  "FieldRead Node=%p SourceDesc=%p Type=%X
  ",

  				  node, source_desc, entry_type));

  		status =
  		    acpi_ex_read_data_from_field(walk_state, source_desc,
  						 &obj_desc);

  		break;

  		/* For these objects, just return the object attached to the Node */

  	case ACPI_TYPE_MUTEX:

  	case ACPI_TYPE_POWER:
  	case ACPI_TYPE_PROCESSOR:

  	case ACPI_TYPE_EVENT:
  	case ACPI_TYPE_REGION:
  
  		/* Return an additional reference to the object */
  
  		obj_desc = source_desc;

  		acpi_ut_add_reference(obj_desc);

  		break;

  		/* TYPE_ANY is untyped, and thus there is no object associated with it */

  
  	case ACPI_TYPE_ANY:

  		ACPI_ERROR((AE_INFO,
  			    "Untyped entry %p, no attached object!", node));

  		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);	/* Cannot be AE_TYPE */

  
  	case ACPI_TYPE_LOCAL_REFERENCE:

  		switch (source_desc->reference.class) {
  		case ACPI_REFCLASS_TABLE:	/* This is a ddb_handle */
  		case ACPI_REFCLASS_REFOF:
  		case ACPI_REFCLASS_INDEX:

  			/* Return an additional reference to the object */
  
  			obj_desc = source_desc;

  			acpi_ut_add_reference(obj_desc);

  			break;
  
  		default:
  			/* No named references are allowed here */

  			ACPI_ERROR((AE_INFO,

  				    "Unsupported Reference type %X",
  				    source_desc->reference.class));

  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);

  		}
  		break;

  	default:

  		/* Default case is for unknown types */

  		ACPI_ERROR((AE_INFO,
  			    "Node %p - Unknown object type %X",
  			    node, entry_type));

  		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);

  	}			/* switch (entry_type) */

  	/* Return the object descriptor */

  	*object_ptr = (void *)obj_desc;
  	return_ACPI_STATUS(status);

  }