drivers/bus/acpi/acpica/utilities/utxfmutex.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: utxfmutex - external AML mutex access functions
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2017, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include "acpi.h"
  45 #include "accommon.h"
  46 #include "acnamesp.h"
  47
  48
  49 #define _COMPONENT          ACPI_UTILITIES
  50         ACPI_MODULE_NAME    ("utxfmutex")
  51
  52
  53 /* Local prototypes */
  54
  55 static ACPI_STATUS
  56 AcpiUtGetMutexObject (
  57     ACPI_HANDLE             Handle,
  58     ACPI_STRING             Pathname,
  59     ACPI_OPERAND_OBJECT     **RetObj);
  60
  61
  62 /*******************************************************************************
  63  *
  64  * FUNCTION:    AcpiUtGetMutexObject
  65  *
  66  * PARAMETERS:  Handle              - Mutex or prefix handle (optional)
  67  *              Pathname            - Mutex pathname (optional)
  68  *              RetObj              - Where the mutex object is returned
  69  *
  70  * RETURN:      Status
  71  *
  72  * DESCRIPTION: Get an AML mutex object. The mutex node is pointed to by
  73  *              Handle:Pathname. Either Handle or Pathname can be NULL, but
  74  *              not both.
  75  *
  76  ******************************************************************************/
  77
  78 static ACPI_STATUS
  79 AcpiUtGetMutexObject (
  80     ACPI_HANDLE             Handle,
  81     ACPI_STRING             Pathname,
  82     ACPI_OPERAND_OBJECT     **RetObj)
  83 {
  84     ACPI_NAMESPACE_NODE     *MutexNode;
  85     ACPI_OPERAND_OBJECT     *MutexObj;
  86     ACPI_STATUS             Status;
  87
  88
  89     /* Parameter validation */
  90
  91     if (!RetObj || (!Handle && !Pathname))
  92     {
  93         return (AE_BAD_PARAMETER);
  94     }
  95
  96     /* Get a the namespace node for the mutex */
  97
  98     MutexNode = Handle;
  99     if (Pathname != NULL)
 100     {
 101         Status = AcpiGetHandle (
 102             Handle, Pathname, ACPI_CAST_PTR (ACPI_HANDLE, &MutexNode));
 103         if (ACPI_FAILURE (Status))
 104         {
 105             return (Status);
 106         }
 107     }
 108
 109     /* Ensure that we actually have a Mutex object */
 110
 111     if (!MutexNode ||
 112         (MutexNode->Type != ACPI_TYPE_MUTEX))
 113     {
 114         return (AE_TYPE);
 115     }
 116
 117     /* Get the low-level mutex object */
 118
 119     MutexObj = AcpiNsGetAttachedObject (MutexNode);
 120     if (!MutexObj)
 121     {
 122         return (AE_NULL_OBJECT);
 123     }
 124
 125     *RetObj = MutexObj;
 126     return (AE_OK);
 127 }
 128
 129
 130 /*******************************************************************************
 131  *
 132  * FUNCTION:    AcpiAcquireMutex
 133  *
 134  * PARAMETERS:  Handle              - Mutex or prefix handle (optional)
 135  *              Pathname            - Mutex pathname (optional)
 136  *              Timeout             - Max time to wait for the lock (millisec)
 137  *
 138  * RETURN:      Status
 139  *
 140  * DESCRIPTION: Acquire an AML mutex. This is a device driver interface to
 141  *              AML mutex objects, and allows for transaction locking between
 142  *              drivers and AML code. The mutex node is pointed to by
 143  *              Handle:Pathname. Either Handle or Pathname can be NULL, but
 144  *              not both.
 145  *
 146  ******************************************************************************/
 147
 148 ACPI_STATUS
 149 AcpiAcquireMutex (
 150     ACPI_HANDLE             Handle,
 151     ACPI_STRING             Pathname,
 152     UINT16                  Timeout)
 153 {
 154     ACPI_STATUS             Status;
 155     ACPI_OPERAND_OBJECT     *MutexObj;
 156
 157
 158     /* Get the low-level mutex associated with Handle:Pathname */
 159
 160     Status = AcpiUtGetMutexObject (Handle, Pathname, &MutexObj);
 161     if (ACPI_FAILURE (Status))
 162     {
 163         return (Status);
 164     }
 165
 166     /* Acquire the OS mutex */
 167
 168     Status = AcpiOsAcquireMutex (MutexObj->Mutex.OsMutex, Timeout);
 169     return (Status);
 170 }
 171
 172 ACPI_EXPORT_SYMBOL (AcpiAcquireMutex)
 173
 174
 175 /*******************************************************************************
 176  *
 177  * FUNCTION:    AcpiReleaseMutex
 178  *
 179  * PARAMETERS:  Handle              - Mutex or prefix handle (optional)
 180  *              Pathname            - Mutex pathname (optional)
 181  *
 182  * RETURN:      Status
 183  *
 184  * DESCRIPTION: Release an AML mutex. This is a device driver interface to
 185  *              AML mutex objects, and allows for transaction locking between
 186  *              drivers and AML code. The mutex node is pointed to by
 187  *              Handle:Pathname. Either Handle or Pathname can be NULL, but
 188  *              not both.
 189  *
 190  ******************************************************************************/
 191
 192 ACPI_STATUS
 193 AcpiReleaseMutex (
 194     ACPI_HANDLE             Handle,
 195     ACPI_STRING             Pathname)
 196 {
 197     ACPI_STATUS             Status;
 198     ACPI_OPERAND_OBJECT     *MutexObj;
 199
 200
 201     /* Get the low-level mutex associated with Handle:Pathname */
 202
 203     Status = AcpiUtGetMutexObject (Handle, Pathname, &MutexObj);
 204     if (ACPI_FAILURE (Status))
 205     {
 206         return (Status);
 207     }
 208
 209     /* Release the OS mutex */
 210
 211     AcpiOsReleaseMutex (MutexObj->Mutex.OsMutex);
 212     return (AE_OK);
 213 }
 214
 215 ACPI_EXPORT_SYMBOL (AcpiReleaseMutex)