drivers/acpi/namespace/nseval.c - kernel/msm-4.9 - Gitiles

 /*******************************************************************************
  *
  * Module Name: nseval - Object evaluation, includes control method execution
  *
  ******************************************************************************/

 /*
  * 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 <acpi/acparser.h>
 #include <acpi/acinterp.h>
 #include <acpi/acnamesp.h>

 #define _COMPONENT          ACPI_NAMESPACE
 ACPI_MODULE_NAME("nseval")

 /*******************************************************************************
  *
  * FUNCTION:    acpi_ns_evaluate
  *
  * PARAMETERS:  Info            - Evaluation info block, contains:
  *                  prefix_node     - Prefix or Method/Object Node to execute
  *                  Pathname        - Name of method to execute, If NULL, the
  *                                    Node is the object to execute
  *                  Parameters      - List of parameters to pass to the method,
  *                                    terminated by NULL. Params itself may be
  *                                    NULL if no parameters are being passed.
  *                  return_object   - Where to put method's return value (if
  *                                    any). If NULL, no value is returned.
  *                  parameter_type  - Type of Parameter list
  *                  return_object   - Where to put method's return value (if
  *                                    any). If NULL, no value is returned.
  *                  Flags           - ACPI_IGNORE_RETURN_VALUE to delete return
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Execute a control method or return the current value of an
  *              ACPI namespace object.
  *
  * MUTEX:       Locks interpreter
  *
  ******************************************************************************/
 acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
 {
 	acpi_status status;
 	struct acpi_namespace_node *node;

 	ACPI_FUNCTION_TRACE(ns_evaluate);

 	if (!info) {
 		return_ACPI_STATUS(AE_BAD_PARAMETER);
 	}

 	/* Initialize the return value to an invalid object */

 	info->return_object = NULL;

 	/*
 	 * Get the actual namespace node for the target object. Handles these cases:
 	 *
 	 * 1) Null node, Pathname (absolute path)
 	 * 2) Node, Pathname (path relative to Node)
 	 * 3) Node, Null Pathname
 	 */
 	status = acpi_ns_get_node(info->prefix_node, info->pathname,
 				  ACPI_NS_NO_UPSEARCH, &info->resolved_node);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}

 	/*
 	 * For a method alias, we must grab the actual method node so that proper
 	 * scoping context will be established before execution.
 	 */
 	if (acpi_ns_get_type(info->resolved_node) ==
 	    ACPI_TYPE_LOCAL_METHOD_ALIAS) {
 		info->resolved_node =
 		    ACPI_CAST_PTR(struct acpi_namespace_node,
 				  info->resolved_node->object);
 	}

 	ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n", info->pathname,
 			  info->resolved_node,
 			  acpi_ns_get_attached_object(info->resolved_node)));

 	node = info->resolved_node;

 	/*
 	 * Two major cases here:
 	 *
 	 * 1) The object is a control method -- execute it
 	 * 2) The object is not a method -- just return it's current value
 	 */
 	if (acpi_ns_get_type(info->resolved_node) == ACPI_TYPE_METHOD) {
 		/*
 		 * 1) Object is a control method - execute it
 		 */

 		/* Verify that there is a method object associated with this node */

 		info->obj_desc =
 		    acpi_ns_get_attached_object(info->resolved_node);
 		if (!info->obj_desc) {
 			ACPI_ERROR((AE_INFO,
 				    "Control method has no attached sub-object"));
 			return_ACPI_STATUS(AE_NULL_OBJECT);
 		}

 		/*
 		 * Calculate the number of arguments being passed to the method
 		 */

 		info->param_count = 0;
 		if (info->parameters) {
 			while (info->parameters[info->param_count])
 				info->param_count++;
 		}

 		/*
 		 * Warning if too few or too many arguments have been passed by the
 		 * caller. We don't want to abort here with an error because an
 		 * incorrect number of arguments may not cause the method to fail.
 		 * However, the method will fail if there are too few arguments passed
 		 * and the method attempts to use one of the missing ones.
 		 */

 		if (info->param_count < info->obj_desc->method.param_count) {
 			ACPI_WARNING((AE_INFO,
 				    "Insufficient arguments - "
 				    "method [%4.4s] needs %d, found %d",
 				    acpi_ut_get_node_name(info->resolved_node),
 				    info->obj_desc->method.param_count,
 				    info->param_count));
 		} else if (info->param_count >
 				info->obj_desc->method.param_count) {
 			ACPI_WARNING((AE_INFO,
 				      "Excess arguments - "
 				      "method [%4.4s] needs %d, found %d",
 				      acpi_ut_get_node_name(info->
 							    resolved_node),
 				      info->obj_desc->method.param_count,
 				      info->param_count));
 		}

 		ACPI_DUMP_PATHNAME(info->resolved_node, "Execute Method:",
 				   ACPI_LV_INFO, _COMPONENT);

 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 				  "Method at AML address %p Length %X\n",
 				  info->obj_desc->method.aml_start + 1,
 				  info->obj_desc->method.aml_length - 1));

 		/*
 		 * Any namespace deletion must acquire both the namespace and
 		 * interpreter locks to ensure that no thread is using the portion of
 		 * the namespace that is being deleted.
 		 *
 		 * Execute the method via the interpreter. The interpreter is locked
 		 * here before calling into the AML parser
 		 */
 		acpi_ex_enter_interpreter();
 		status = acpi_ps_execute_method(info);
 		acpi_ex_exit_interpreter();
 	} else {
 		/*
 		 * 2) Object is not a method, return its current value
 		 *
 		 * Disallow certain object types. For these, "evaluation" is undefined.
 		 */
 		switch (info->resolved_node->type) {
 		case ACPI_TYPE_DEVICE:
 		case ACPI_TYPE_EVENT:
 		case ACPI_TYPE_MUTEX:
 		case ACPI_TYPE_REGION:
 		case ACPI_TYPE_THERMAL:
 		case ACPI_TYPE_LOCAL_SCOPE:

 			ACPI_ERROR((AE_INFO,
 				    "[%4.4s] Evaluation of object type [%s] is not supported",
 				    info->resolved_node->name.ascii,
 				    acpi_ut_get_type_name(info->resolved_node->
 							  type)));

 			return_ACPI_STATUS(AE_TYPE);

 		default:
 			break;
 		}

 		/*
 		 * Objects require additional resolution steps (e.g., the Node may be
 		 * a field that must be read, etc.) -- we can't just grab the object
 		 * out of the node.
 		 *
 		 * Use resolve_node_to_value() to get the associated value.
 		 *
 		 * NOTE: we can get away with passing in NULL for a walk state because
 		 * resolved_node is guaranteed to not be a reference to either a method
 		 * local or a method argument (because this interface is never called
 		 * from a running method.)
 		 *
 		 * Even though we do not directly invoke the interpreter for object
 		 * resolution, we must lock it because we could access an opregion.
 		 * The opregion access code assumes that the interpreter is locked.
 		 */
 		acpi_ex_enter_interpreter();

 		/* Function has a strange interface */

 		status =
 		    acpi_ex_resolve_node_to_value(&info->resolved_node, NULL);
 		acpi_ex_exit_interpreter();

 		/*
 		 * If acpi_ex_resolve_node_to_value() succeeded, the return value was placed
 		 * in resolved_node.
 		 */
 		if (ACPI_SUCCESS(status)) {
 			status = AE_CTRL_RETURN_VALUE;
 			info->return_object =
 			    ACPI_CAST_PTR(union acpi_operand_object,
 					  info->resolved_node);

 			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
 					  "Returning object %p [%s]\n",
 					  info->return_object,
 					  acpi_ut_get_object_type_name(info->
 								       return_object)));
 		}
 	}

 	/* Validation of return values for ACPI-predefined methods and objects */

 	if ((status == AE_OK) || (status == AE_CTRL_RETURN_VALUE)) {
 		/*
 		 * If this is the first evaluation, check the return value. This
 		 * ensures that any warnings will only be emitted during the very
 		 * first evaluation of the object.
 		 */
 		if (!(node->flags & ANOBJ_EVALUATED)) {
 			/*
 			 * Check for a predefined ACPI name. If found, validate the
 			 * returned object.
 			 *
 			 * Note: Ignore return status for now, emit warnings if there are
 			 * problems with the returned object. May change later to abort
 			 * the method on invalid return object.
 			 */
 			(void)acpi_ns_check_predefined_names(node,
 							     info->
 							     return_object);
 		}

 		/* Mark the node as having been evaluated */

 		node->flags |= ANOBJ_EVALUATED;
 	}

 	/* Check if there is a return value that must be dealt with */

 	if (status == AE_CTRL_RETURN_VALUE) {

 		/* If caller does not want the return value, delete it */

 		if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
 			acpi_ut_remove_reference(info->return_object);
 			info->return_object = NULL;
 		}

 		/* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */

 		status = AE_OK;
 	}

 	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
 			  "*** Completed evaluation of object %s ***\n",
 			  info->pathname));

 	/*
 	 * Namespace was unlocked by the handling acpi_ns* function, so we
 	 * just return
 	 */
 	return_ACPI_STATUS(status);
 }
	/*******************************************************************************
	*
	* Module Name: nseval - Object evaluation, includes control method execution
	*
	******************************************************************************/

	/*
	* 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 <acpi/acparser.h>
	#include <acpi/acinterp.h>
	#include <acpi/acnamesp.h>

	#define _COMPONENT ACPI_NAMESPACE
	ACPI_MODULE_NAME("nseval")

	/*******************************************************************************
	*
	* FUNCTION: acpi_ns_evaluate
	*
	* PARAMETERS: Info - Evaluation info block, contains:
	* prefix_node - Prefix or Method/Object Node to execute
	* Pathname - Name of method to execute, If NULL, the
	* Node is the object to execute
	* Parameters - List of parameters to pass to the method,
	* terminated by NULL. Params itself may be
	* NULL if no parameters are being passed.
	* return_object - Where to put method's return value (if
	* any). If NULL, no value is returned.
	* parameter_type - Type of Parameter list
	* return_object - Where to put method's return value (if
	* any). If NULL, no value is returned.
	* Flags - ACPI_IGNORE_RETURN_VALUE to delete return
	*
	* RETURN: Status
	*
	* DESCRIPTION: Execute a control method or return the current value of an
	* ACPI namespace object.
	*
	* MUTEX: Locks interpreter
	*
	******************************************************************************/
	acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
	{
	acpi_status status;
	struct acpi_namespace_node *node;

	ACPI_FUNCTION_TRACE(ns_evaluate);

	if (!info) {
	return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	/* Initialize the return value to an invalid object */

	info->return_object = NULL;

	/*
	* Get the actual namespace node for the target object. Handles these cases:
	*
	* 1) Null node, Pathname (absolute path)
	* 2) Node, Pathname (path relative to Node)
	* 3) Node, Null Pathname
	*/
	status = acpi_ns_get_node(info->prefix_node, info->pathname,
	ACPI_NS_NO_UPSEARCH, &info->resolved_node);
	if (ACPI_FAILURE(status)) {
	return_ACPI_STATUS(status);
	}

	/*
	* For a method alias, we must grab the actual method node so that proper
	* scoping context will be established before execution.
	*/
	if (acpi_ns_get_type(info->resolved_node) ==
	ACPI_TYPE_LOCAL_METHOD_ALIAS) {
	info->resolved_node =
	ACPI_CAST_PTR(struct acpi_namespace_node,
	info->resolved_node->object);
	}

	ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n", info->pathname,
	info->resolved_node,
	acpi_ns_get_attached_object(info->resolved_node)));

	node = info->resolved_node;

	/*
	* Two major cases here:
	*
	* 1) The object is a control method -- execute it
	* 2) The object is not a method -- just return it's current value
	*/
	if (acpi_ns_get_type(info->resolved_node) == ACPI_TYPE_METHOD) {
	/*
	* 1) Object is a control method - execute it
	*/

	/* Verify that there is a method object associated with this node */

	info->obj_desc =
	acpi_ns_get_attached_object(info->resolved_node);
	if (!info->obj_desc) {
	ACPI_ERROR((AE_INFO,
	"Control method has no attached sub-object"));
	return_ACPI_STATUS(AE_NULL_OBJECT);
	}

	/*
	* Calculate the number of arguments being passed to the method
	*/

	info->param_count = 0;
	if (info->parameters) {
	while (info->parameters[info->param_count])
	info->param_count++;
	}

	/*
	* Warning if too few or too many arguments have been passed by the
	* caller. We don't want to abort here with an error because an
	* incorrect number of arguments may not cause the method to fail.
	* However, the method will fail if there are too few arguments passed
	* and the method attempts to use one of the missing ones.
	*/

	if (info->param_count < info->obj_desc->method.param_count) {
	ACPI_WARNING((AE_INFO,
	"Insufficient arguments - "
	"method [%4.4s] needs %d, found %d",
	acpi_ut_get_node_name(info->resolved_node),
	info->obj_desc->method.param_count,
	info->param_count));
	} else if (info->param_count >
	info->obj_desc->method.param_count) {
	ACPI_WARNING((AE_INFO,
	"Excess arguments - "
	"method [%4.4s] needs %d, found %d",
	acpi_ut_get_node_name(info->
	resolved_node),
	info->obj_desc->method.param_count,
	info->param_count));
	}

	ACPI_DUMP_PATHNAME(info->resolved_node, "Execute Method:",
	ACPI_LV_INFO, _COMPONENT);

	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
	"Method at AML address %p Length %X\n",
	info->obj_desc->method.aml_start + 1,
	info->obj_desc->method.aml_length - 1));

	/*
	* Any namespace deletion must acquire both the namespace and
	* interpreter locks to ensure that no thread is using the portion of
	* the namespace that is being deleted.
	*
	* Execute the method via the interpreter. The interpreter is locked
	* here before calling into the AML parser
	*/
	acpi_ex_enter_interpreter();
	status = acpi_ps_execute_method(info);
	acpi_ex_exit_interpreter();
	} else {
	/*
	* 2) Object is not a method, return its current value
	*
	* Disallow certain object types. For these, "evaluation" is undefined.
	*/
	switch (info->resolved_node->type) {
	case ACPI_TYPE_DEVICE:
	case ACPI_TYPE_EVENT:
	case ACPI_TYPE_MUTEX:
	case ACPI_TYPE_REGION:
	case ACPI_TYPE_THERMAL:
	case ACPI_TYPE_LOCAL_SCOPE:

	ACPI_ERROR((AE_INFO,
	"[%4.4s] Evaluation of object type [%s] is not supported",
	info->resolved_node->name.ascii,
	acpi_ut_get_type_name(info->resolved_node->
	type)));

	return_ACPI_STATUS(AE_TYPE);

	default:
	break;
	}

	/*
	* Objects require additional resolution steps (e.g., the Node may be
	* a field that must be read, etc.) -- we can't just grab the object
	* out of the node.
	*
	* Use resolve_node_to_value() to get the associated value.
	*
	* NOTE: we can get away with passing in NULL for a walk state because
	* resolved_node is guaranteed to not be a reference to either a method
	* local or a method argument (because this interface is never called
	* from a running method.)
	*
	* Even though we do not directly invoke the interpreter for object
	* resolution, we must lock it because we could access an opregion.
	* The opregion access code assumes that the interpreter is locked.
	*/
	acpi_ex_enter_interpreter();

	/* Function has a strange interface */

	status =
	acpi_ex_resolve_node_to_value(&info->resolved_node, NULL);
	acpi_ex_exit_interpreter();

	/*
	* If acpi_ex_resolve_node_to_value() succeeded, the return value was placed
	* in resolved_node.
	*/
	if (ACPI_SUCCESS(status)) {
	status = AE_CTRL_RETURN_VALUE;
	info->return_object =
	ACPI_CAST_PTR(union acpi_operand_object,
	info->resolved_node);

	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
	"Returning object %p [%s]\n",
	info->return_object,
	acpi_ut_get_object_type_name(info->
	return_object)));
	}
	}

	/* Validation of return values for ACPI-predefined methods and objects */

	if ((status == AE_OK) \|\| (status == AE_CTRL_RETURN_VALUE)) {
	/*
	* If this is the first evaluation, check the return value. This
	* ensures that any warnings will only be emitted during the very
	* first evaluation of the object.
	*/
	if (!(node->flags & ANOBJ_EVALUATED)) {
	/*
	* Check for a predefined ACPI name. If found, validate the
	* returned object.
	*
	* Note: Ignore return status for now, emit warnings if there are
	* problems with the returned object. May change later to abort
	* the method on invalid return object.
	*/
	(void)acpi_ns_check_predefined_names(node,
	info->
	return_object);
	}

	/* Mark the node as having been evaluated */

	node->flags \|= ANOBJ_EVALUATED;
	}

	/* Check if there is a return value that must be dealt with */

	if (status == AE_CTRL_RETURN_VALUE) {

	/* If caller does not want the return value, delete it */

	if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
	acpi_ut_remove_reference(info->return_object);
	info->return_object = NULL;
	}

	/* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */

	status = AE_OK;
	}

	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
	"* Completed evaluation of object %s *\n",
	info->pathname));

	/*
	* Namespace was unlocked by the handling acpi_ns* function, so we
	* just return
	*/
	return_ACPI_STATUS(status);
	}