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/******************************************************************************

 *

 * Module Name: psargs - Parse AML opcode arguments

 *

 *****************************************************************************/

/*

 * Copyright (C) 2000 - 2015, 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 

#include "accommon.h"

#include "acparser.h"

#include "amlcode.h"

#include "acnamesp.h"

#include "acdispat.h"

#define _COMPONENT          ACPI_PARSER

ACPI_MODULE_NAME("psargs")

/* Local prototypes */

static u32

acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state);

static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state

						       *parser_state);

/*******************************************************************************

 *

 * FUNCTION:    acpi_ps_get_next_package_length

 *

 * PARAMETERS:  parser_state        - Current parser state object

 *

 * RETURN:      Decoded package length. On completion, the AML pointer points

 *              past the length byte or bytes.

 *

 * DESCRIPTION: Decode and return a package length field.

 *              Note: Largest package length is 28 bits, from ACPI specification

 *

 ******************************************************************************/

static u32

acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state)

{

	u8 *aml = parser_state->aml;

	u32 package_length = 0;

	u32 byte_count;

	u8 byte_zero_mask = 0x3F;	/* Default [0:5] */

	ACPI_FUNCTION_TRACE(ps_get_next_package_length);

	/*

	 * Byte 0 bits [6:7] contain the number of additional bytes

	 * used to encode the package length, either 0,1,2, or 3

	 */

	byte_count = (aml[0] >> 6);

	parser_state->aml += ((acpi_size) byte_count + 1);

	/* Get bytes 3, 2, 1 as needed */

	while (byte_count) {

		/*

		 * Final bit positions for the package length bytes:

		 *      Byte3->[20:27]

		 *      Byte2->[12:19]

		 *      Byte1->[04:11]

		 *      Byte0->[00:03]

		 */

		package_length |= (aml[byte_count] << ((byte_count << 3) - 4));

		byte_zero_mask = 0x0F;	/* Use bits [0:3] of byte 0 */

		byte_count--;

	}

	/* Byte 0 is a special case, either bits [0:3] or [0:5] are used */

	package_length |= (aml[0] & byte_zero_mask);

	return_UINT32(package_length);

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_ps_get_next_package_end

 *

 * PARAMETERS:  parser_state        - Current parser state object

 *

 * RETURN:      Pointer to end-of-package +1

 *

 * DESCRIPTION: Get next package length and return a pointer past the end of

 *              the package. Consumes the package length field

 *

 ******************************************************************************/

u8 *acpi_ps_get_next_package_end(struct acpi_parse_state *parser_state)

{

	u8 *start = parser_state->aml;

	u32 package_length;

	ACPI_FUNCTION_TRACE(ps_get_next_package_end);

	/* Function below updates parser_state->Aml */

	package_length = acpi_ps_get_next_package_length(parser_state);

	return_PTR(start + package_length);	/* end of package */

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_ps_get_next_namestring

 *

 * PARAMETERS:  parser_state        - Current parser state object

 *

 * RETURN:      Pointer to the start of the name string (pointer points into

 *              the AML.

 *

 * DESCRIPTION: Get next raw namestring within the AML stream. Handles all name

 *              prefix characters. Set parser state to point past the string.

 *              (Name is consumed from the AML.)

 *

 ******************************************************************************/

char *acpi_ps_get_next_namestring(struct acpi_parse_state *parser_state)

{

	u8 *start = parser_state->aml;

	u8 *end = parser_state->aml;

	ACPI_FUNCTION_TRACE(ps_get_next_namestring);

	/* Point past any namestring prefix characters (backslash or carat) */

	while (ACPI_IS_ROOT_PREFIX(*end) || ACPI_IS_PARENT_PREFIX(*end)) {

		end++;

	}

	/* Decode the path prefix character */

	switch (*end) {

	case 0:

		/* null_name */

		if (end == start) {

			start = NULL;

		}

		end++;

		break;

	case AML_DUAL_NAME_PREFIX:

		/* Two name segments */

		end += 1 + (2 * ACPI_NAME_SIZE);

		break;

	case AML_MULTI_NAME_PREFIX_OP:

		/* Multiple name segments, 4 chars each, count in next byte */

		end += 2 + (*(end + 1) * ACPI_NAME_SIZE);

		break;

	default:

		/* Single name segment */

		end += ACPI_NAME_SIZE;

		break;

	}

	parser_state->aml = end;

	return_PTR((char *)start);

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_ps_get_next_namepath

 *

 * PARAMETERS:  parser_state        - Current parser state object

 *              arg                 - Where the namepath will be stored

 *              arg_count           - If the namepath points to a control method

 *                                    the method's argument is returned here.

 *              possible_method_call - Whether the namepath can possibly be the

 *                                    start of a method call

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Get next name (if method call, return # of required args).

 *              Names are looked up in the internal namespace to determine

 *              if the name represents a control method. If a method

 *              is found, the number of arguments to the method is returned.

 *              This information is critical for parsing to continue correctly.

 *

 ******************************************************************************/

acpi_status

acpi_ps_get_next_namepath(struct acpi_walk_state *walk_state,

			  struct acpi_parse_state *parser_state,

			  union acpi_parse_object *arg, u8 possible_method_call)

{

	acpi_status status;

	char *path;

	union acpi_parse_object *name_op;

	union acpi_operand_object *method_desc;

	struct acpi_namespace_node *node;

	u8 *start = parser_state->aml;

	ACPI_FUNCTION_TRACE(ps_get_next_namepath);

	path = acpi_ps_get_next_namestring(parser_state);

	acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);

	/* Null path case is allowed, just exit */

	if (!path) {

		arg->common.value.name = path;

		return_ACPI_STATUS(AE_OK);

	}

	/*

	 * Lookup the name in the internal namespace, starting with the current

	 * scope. We don't want to add anything new to the namespace here,

	 * however, so we use MODE_EXECUTE.

	 * Allow searching of the parent tree, but don't open a new scope -

	 * we just want to lookup the object (must be mode EXECUTE to perform

	 * the upsearch)

	 */

	status = acpi_ns_lookup(walk_state->scope_info, path,

				ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,

				ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,

				NULL, &node);

	/*

	 * If this name is a control method invocation, we must

	 * setup the method call

	 */

	if (ACPI_SUCCESS(status) &&

	    possible_method_call && (node->type == ACPI_TYPE_METHOD)) {

		if (walk_state->opcode == AML_UNLOAD_OP) {

			/*

			 * acpi_ps_get_next_namestring has increased the AML pointer,

			 * so we need to restore the saved AML pointer for method call.

			 */

			walk_state->parser_state.aml = start;

			walk_state->arg_count = 1;

			acpi_ps_init_op(arg, AML_INT_METHODCALL_OP);

			return_ACPI_STATUS(AE_OK);

		}

		/* This name is actually a control method invocation */

		method_desc = acpi_ns_get_attached_object(node);

		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,

				  "Control Method - %p Desc %p Path=%p\n", node,

				  method_desc, path));

		name_op = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP, start);

		if (!name_op) {

			return_ACPI_STATUS(AE_NO_MEMORY);

		}

		/* Change Arg into a METHOD CALL and attach name to it */

		acpi_ps_init_op(arg, AML_INT_METHODCALL_OP);

		name_op->common.value.name = path;

		/* Point METHODCALL/NAME to the METHOD Node */

		name_op->common.node = node;

		acpi_ps_append_arg(arg, name_op);

		if (!method_desc) {

			ACPI_ERROR((AE_INFO,

				    "Control Method %p has no attached object",

				    node));

			return_ACPI_STATUS(AE_AML_INTERNAL);

		}

		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,

				  "Control Method - %p Args %X\n",

				  node, method_desc->method.param_count));

		/* Get the number of arguments to expect */

		walk_state->arg_count = method_desc->method.param_count;

		return_ACPI_STATUS(AE_OK);

	}

	/*

	 * Special handling if the name was not found during the lookup -

	 * some not_found cases are allowed

	 */

	if (status == AE_NOT_FOUND) {

		/* 1) not_found is ok during load pass 1/2 (allow forward references) */

		if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) !=

		    ACPI_PARSE_EXECUTE) {

			status = AE_OK;

		}

		/* 2) not_found during a cond_ref_of(x) is ok by definition */

		else if (walk_state->op->common.aml_opcode ==

			 AML_COND_REF_OF_OP) {

			status = AE_OK;

		}

		/*

		 * 3) not_found while building a Package is ok at this point, we

		 * may flag as an error later if slack mode is not enabled.

		 * (Some ASL code depends on allowing this behavior)

		 */

		else if ((arg->common.parent) &&

			 ((arg->common.parent->common.aml_opcode ==

			   AML_PACKAGE_OP)

			  || (arg->common.parent->common.aml_opcode ==

			      AML_VAR_PACKAGE_OP))) {

			status = AE_OK;

		}

	}

	/* Final exception check (may have been changed from code above) */

	if (ACPI_FAILURE(status)) {

		ACPI_ERROR_NAMESPACE(path, status);

		if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) ==

		    ACPI_PARSE_EXECUTE) {

			/* Report a control method execution error */

			status = acpi_ds_method_error(status, walk_state);

		}

	}

	/* Save the namepath */

	arg->common.value.name = path;

	return_ACPI_STATUS(status);

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_ps_get_next_simple_arg

 *

 * PARAMETERS:  parser_state        - Current parser state object

 *              arg_type            - The argument type (AML_*_ARG)

 *              arg                 - Where the argument is returned

 *

 * RETURN:      None

 *

 * DESCRIPTION: Get the next simple argument (constant, string, or namestring)

 *

 ******************************************************************************/

void

acpi_ps_get_next_simple_arg(struct acpi_parse_state *parser_state,

			    u32 arg_type, union acpi_parse_object *arg)

{

	u32 length;

	u16 opcode;

	u8 *aml = parser_state->aml;

	ACPI_FUNCTION_TRACE_U32(ps_get_next_simple_arg, arg_type);

	switch (arg_type) {

	case ARGP_BYTEDATA:

		/* Get 1 byte from the AML stream */

		opcode = AML_BYTE_OP;

		arg->common.value.integer = (u64) *aml;

		length = 1;

		break;

	case ARGP_WORDDATA:

		/* Get 2 bytes from the AML stream */

		opcode = AML_WORD_OP;

		ACPI_MOVE_16_TO_64(&arg->common.value.integer, aml);

		length = 2;

		break;

	case ARGP_DWORDDATA:

		/* Get 4 bytes from the AML stream */

		opcode = AML_DWORD_OP;

		ACPI_MOVE_32_TO_64(&arg->common.value.integer, aml);

		length = 4;

		break;

	case ARGP_QWORDDATA:

		/* Get 8 bytes from the AML stream */

		opcode = AML_QWORD_OP;

		ACPI_MOVE_64_TO_64(&arg->common.value.integer, aml);

		length = 8;

		break;

	case ARGP_CHARLIST:

		/* Get a pointer to the string, point past the string */

		opcode = AML_STRING_OP;

		arg->common.value.string = ACPI_CAST_PTR(char, aml);

		/* Find the null terminator */

		length = 0;

		while (aml[length]) {

			length++;

		}

		length++;

		break;

	case ARGP_NAME:

	case ARGP_NAMESTRING:

		acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);

		arg->common.value.name =

		    acpi_ps_get_next_namestring(parser_state);

		return_VOID;

	default:

		ACPI_ERROR((AE_INFO, "Invalid ArgType 0x%X", arg_type));

		return_VOID;

	}

	acpi_ps_init_op(arg, opcode);

	parser_state->aml += length;

	return_VOID;

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_ps_get_next_field

 *

 * PARAMETERS:  parser_state        - Current parser state object

 *

 * RETURN:      A newly allocated FIELD op

 *

 * DESCRIPTION: Get next field (named_field, reserved_field, or access_field)

 *

 ******************************************************************************/

static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state

						       *parser_state)

{

	u8 *aml;

	union acpi_parse_object *field;

	union acpi_parse_object *arg = NULL;

	u16 opcode;

	u32 name;

	u8 access_type;

	u8 access_attribute;

	u8 access_length;

	u32 pkg_length;

	u8 *pkg_end;

	u32 buffer_length;

	ACPI_FUNCTION_TRACE(ps_get_next_field);

	aml = parser_state->aml;

	/* Determine field type */

	switch (ACPI_GET8(parser_state->aml)) {

	case AML_FIELD_OFFSET_OP:

		opcode = AML_INT_RESERVEDFIELD_OP;

		parser_state->aml++;

		break;

	case AML_FIELD_ACCESS_OP:

		opcode = AML_INT_ACCESSFIELD_OP;

		parser_state->aml++;

		break;

	case AML_FIELD_CONNECTION_OP:

		opcode = AML_INT_CONNECTION_OP;

		parser_state->aml++;

		break;

	case AML_FIELD_EXT_ACCESS_OP:

		opcode = AML_INT_EXTACCESSFIELD_OP;

		parser_state->aml++;

		break;

	default:

		opcode = AML_INT_NAMEDFIELD_OP;

		break;

	}

	/* Allocate a new field op */

	field = acpi_ps_alloc_op(opcode, aml);

	if (!field) {

		return_PTR(NULL);

	}

	/* Decode the field type */

	switch (opcode) {

	case AML_INT_NAMEDFIELD_OP:

		/* Get the 4-character name */

		ACPI_MOVE_32_TO_32(&name, parser_state->aml);

		acpi_ps_set_name(field, name);

		parser_state->aml += ACPI_NAME_SIZE;

		/* Get the length which is encoded as a package length */

		field->common.value.size =

		    acpi_ps_get_next_package_length(parser_state);

		break;

	case AML_INT_RESERVEDFIELD_OP:

		/* Get the length which is encoded as a package length */

		field->common.value.size =

		    acpi_ps_get_next_package_length(parser_state);

		break;

	case AML_INT_ACCESSFIELD_OP:

	case AML_INT_EXTACCESSFIELD_OP:

		/*

		 * Get access_type and access_attrib and merge into the field Op

		 * access_type is first operand, access_attribute is second. stuff

		 * these bytes into the node integer value for convenience.

		 */

		/* Get the two bytes (Type/Attribute) */

		access_type = ACPI_GET8(parser_state->aml);

		parser_state->aml++;

		access_attribute = ACPI_GET8(parser_state->aml);

		parser_state->aml++;

		field->common.value.integer = (u8)access_type;

		field->common.value.integer |= (u16)(access_attribute << 8);

		/* This opcode has a third byte, access_length */

		if (opcode == AML_INT_EXTACCESSFIELD_OP) {

			access_length = ACPI_GET8(parser_state->aml);

			parser_state->aml++;

			field->common.value.integer |=

			    (u32)(access_length << 16);

		}

		break;

	case AML_INT_CONNECTION_OP:

		/*

		 * Argument for Connection operator can be either a Buffer

		 * (resource descriptor), or a name_string.

		 */

		aml = parser_state->aml;

		if (ACPI_GET8(parser_state->aml) == AML_BUFFER_OP) {

			parser_state->aml++;

			pkg_end = parser_state->aml;

			pkg_length =

			    acpi_ps_get_next_package_length(parser_state);

			pkg_end += pkg_length;

			if (parser_state->aml < pkg_end) {

				/* Non-empty list */

				arg =

				    acpi_ps_alloc_op(AML_INT_BYTELIST_OP, aml);

				if (!arg) {

					acpi_ps_free_op(field);

					return_PTR(NULL);

				}

				/* Get the actual buffer length argument */

				opcode = ACPI_GET8(parser_state->aml);

				parser_state->aml++;

				switch (opcode) {

				case AML_BYTE_OP:	/* AML_BYTEDATA_ARG */

					buffer_length =

					    ACPI_GET8(parser_state->aml);

					parser_state->aml += 1;

					break;

				case AML_WORD_OP:	/* AML_WORDDATA_ARG */

					buffer_length =

					    ACPI_GET16(parser_state->aml);

					parser_state->aml += 2;

					break;

				case AML_DWORD_OP:	/* AML_DWORDATA_ARG */

					buffer_length =

					    ACPI_GET32(parser_state->aml);

					parser_state->aml += 4;

					break;

				default:

					buffer_length = 0;

					break;

				}

				/* Fill in bytelist data */

				arg->named.value.size = buffer_length;

				arg->named.data = parser_state->aml;

			}

			/* Skip to End of byte data */

			parser_state->aml = pkg_end;

		} else {

			arg = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP, aml);

			if (!arg) {

				acpi_ps_free_op(field);

				return_PTR(NULL);

			}

			/* Get the Namestring argument */

			arg->common.value.name =

			    acpi_ps_get_next_namestring(parser_state);

		}

		/* Link the buffer/namestring to parent (CONNECTION_OP) */

		acpi_ps_append_arg(field, arg);

		break;

	default:

		/* Opcode was set in previous switch */

		break;

	}

	return_PTR(field);

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_ps_get_next_arg

 *

 * PARAMETERS:  walk_state          - Current state

 *              parser_state        - Current parser state object

 *              arg_type            - The argument type (AML_*_ARG)

 *              return_arg          - Where the next arg is returned

 *

 * RETURN:      Status, and an op object containing the next argument.

 *

 * DESCRIPTION: Get next argument (including complex list arguments that require

 *              pushing the parser stack)

 *

 ******************************************************************************/

acpi_status

acpi_ps_get_next_arg(struct acpi_walk_state *walk_state,

		     struct acpi_parse_state *parser_state,

		     u32 arg_type, union acpi_parse_object **return_arg)

{

	union acpi_parse_object *arg = NULL;

	union acpi_parse_object *prev = NULL;

	union acpi_parse_object *field;

	u32 subop;

	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE_PTR(ps_get_next_arg, parser_state);

	switch (arg_type) {

	case ARGP_BYTEDATA:

	case ARGP_WORDDATA:

	case ARGP_DWORDDATA:

	case ARGP_CHARLIST:

	case ARGP_NAME:

	case ARGP_NAMESTRING:

		/* Constants, strings, and namestrings are all the same size */

		arg = acpi_ps_alloc_op(AML_BYTE_OP, parser_state->aml);

		if (!arg) {

			return_ACPI_STATUS(AE_NO_MEMORY);

		}

		acpi_ps_get_next_simple_arg(parser_state, arg_type, arg);

		break;

	case ARGP_PKGLENGTH:

		/* Package length, nothing returned */

		parser_state->pkg_end =

		    acpi_ps_get_next_package_end(parser_state);

		break;

	case ARGP_FIELDLIST:

		if (parser_state->aml < parser_state->pkg_end) {

			/* Non-empty list */

			while (parser_state->aml < parser_state->pkg_end) {

				field = acpi_ps_get_next_field(parser_state);

				if (!field) {

					return_ACPI_STATUS(AE_NO_MEMORY);

				}

				if (prev) {

					prev->common.next = field;

				} else {

					arg = field;

				}

				prev = field;

			}

			/* Skip to End of byte data */

			parser_state->aml = parser_state->pkg_end;

		}

		break;

	case ARGP_BYTELIST:

		if (parser_state->aml < parser_state->pkg_end) {

			/* Non-empty list */

			arg = acpi_ps_alloc_op(AML_INT_BYTELIST_OP,

					       parser_state->aml);

			if (!arg) {

				return_ACPI_STATUS(AE_NO_MEMORY);

			}

			/* Fill in bytelist data */

			arg->common.value.size = (u32)

			    ACPI_PTR_DIFF(parser_state->pkg_end,

					  parser_state->aml);

			arg->named.data = parser_state->aml;

			/* Skip to End of byte data */

			parser_state->aml = parser_state->pkg_end;

		}

		break;

	case ARGP_TARGET:

	case ARGP_SUPERNAME:

	case ARGP_SIMPLENAME:

		subop = acpi_ps_peek_opcode(parser_state);

		if (subop == 0 ||

		    acpi_ps_is_leading_char(subop) ||

		    ACPI_IS_ROOT_PREFIX(subop) ||

		    ACPI_IS_PARENT_PREFIX(subop)) {

			/* null_name or name_string */

			arg =

			    acpi_ps_alloc_op(AML_INT_NAMEPATH_OP,

					     parser_state->aml);

			if (!arg) {

				return_ACPI_STATUS(AE_NO_MEMORY);

			}

			/* To support super_name arg of Unload */

			if (walk_state->opcode == AML_UNLOAD_OP) {

				status =

				    acpi_ps_get_next_namepath(walk_state,

							      parser_state, arg,

							      1);

				/*

				 * If the super_name arg of Unload is a method call,

				 * we have restored the AML pointer, just free this Arg

				 */

				if (arg->common.aml_opcode ==

				    AML_INT_METHODCALL_OP) {

					acpi_ps_free_op(arg);

					arg = NULL;

				}

			} else {

				status =

				    acpi_ps_get_next_namepath(walk_state,

							      parser_state, arg,

							      0);

			}

		} else {

			/* Single complex argument, nothing returned */

			walk_state->arg_count = 1;

		}

		break;

	case ARGP_DATAOBJ:

	case ARGP_TERMARG:

		/* Single complex argument, nothing returned */

		walk_state->arg_count = 1;

		break;

	case ARGP_DATAOBJLIST:

	case ARGP_TERMLIST:

	case ARGP_OBJLIST:

		if (parser_state->aml < parser_state->pkg_end) {

			/* Non-empty list of variable arguments, nothing returned */

			walk_state->arg_count = ACPI_VAR_ARGS;

		}

		break;

	default:

		ACPI_ERROR((AE_INFO, "Invalid ArgType: 0x%X", arg_type));

		status = AE_AML_OPERAND_TYPE;

		break;

	}

	*return_arg = arg;

	return_ACPI_STATUS(status);

}