// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/*******************************************************************************
*
* Module Name: utxfmutex - external AML mutex access functions
*
******************************************************************************/
#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);
}
ACPI_EXPORT_SYMBOL(acpi_acquire_mutex)
/*******************************************************************************
*
* 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);
}
ACPI_EXPORT_SYMBOL(acpi_release_mutex)
