blob: 1427d191d15af43b85838e5f61ffb2599c96b2ee [file] [log] [blame]
/*******************************************************************************
*
* Module Name: utxfmutex - external AML mutex access functions
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2012, 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 "acnamesp.h"
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME("utxfmutex")
/* Local prototypes */
static acpi_status
acpi_ut_get_mutex_object(acpi_handle handle,
acpi_string pathname,
union acpi_operand_object **ret_obj);
/*******************************************************************************
*
* FUNCTION: acpi_ut_get_mutex_object
*
* PARAMETERS: Handle - Mutex or prefix handle (optional)
* Pathname - Mutex pathname (optional)
* ret_obj - Where the mutex object is returned
*
* RETURN: Status
*
* DESCRIPTION: Get an AML mutex object. The mutex node is pointed to by
* Handle:Pathname. Either Handle or Pathname can be NULL, but
* not both.
*
******************************************************************************/
static acpi_status
acpi_ut_get_mutex_object(acpi_handle handle,
acpi_string pathname,
union acpi_operand_object **ret_obj)
{
struct acpi_namespace_node *mutex_node;
union acpi_operand_object *mutex_obj;
acpi_status status;
/* Parameter validation */
if (!ret_obj || (!handle && !pathname)) {
return (AE_BAD_PARAMETER);
}
/* Get a the namespace node for the mutex */
mutex_node = handle;
if (pathname != NULL) {
status = acpi_get_handle(handle, pathname,
ACPI_CAST_PTR(acpi_handle,
&mutex_node));
if (ACPI_FAILURE(status)) {
return (status);
}
}
/* Ensure that we actually have a Mutex object */
if (!mutex_node || (mutex_node->type != ACPI_TYPE_MUTEX)) {
return (AE_TYPE);
}
/* Get the low-level mutex object */
mutex_obj = acpi_ns_get_attached_object(mutex_node);
if (!mutex_obj) {
return (AE_NULL_OBJECT);
}
*ret_obj = mutex_obj;
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_acquire_mutex
*
* PARAMETERS: Handle - Mutex or prefix handle (optional)
* Pathname - Mutex pathname (optional)
* Timeout - Max time to wait for the lock (millisec)
*
* RETURN: Status
*
* DESCRIPTION: Acquire an AML mutex. This is a device driver interface to
* AML mutex objects, and allows for transaction locking between
* drivers and AML code. The mutex node is pointed to by
* Handle:Pathname. Either Handle or Pathname can be NULL, but
* not both.
*
******************************************************************************/
acpi_status
acpi_acquire_mutex(acpi_handle handle, acpi_string pathname, u16 timeout)
{
acpi_status status;
union acpi_operand_object *mutex_obj;
/* Get the low-level mutex associated with Handle:Pathname */
status = acpi_ut_get_mutex_object(handle, pathname, &mutex_obj);
if (ACPI_FAILURE(status)) {
return (status);
}
/* Acquire the OS mutex */
status = acpi_os_acquire_mutex(mutex_obj->mutex.os_mutex, timeout);
return (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_release_mutex
*
* PARAMETERS: Handle - Mutex or prefix handle (optional)
* Pathname - Mutex pathname (optional)
*
* RETURN: Status
*
* DESCRIPTION: Release an AML mutex. This is a device driver interface to
* AML mutex objects, and allows for transaction locking between
* drivers and AML code. The mutex node is pointed to by
* Handle:Pathname. Either Handle or Pathname can be NULL, but
* not both.
*
******************************************************************************/
acpi_status acpi_release_mutex(acpi_handle handle, acpi_string pathname)
{
acpi_status status;
union acpi_operand_object *mutex_obj;
/* Get the low-level mutex associated with Handle:Pathname */
status = acpi_ut_get_mutex_object(handle, pathname, &mutex_obj);
if (ACPI_FAILURE(status)) {
return (status);
}
/* Release the OS mutex */
acpi_os_release_mutex(mutex_obj->mutex.os_mutex);
return (AE_OK);
}