sys/OSThermalNotification.c

   1 /*
   2  * Copyright (c) 2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #include <dispatch/dispatch.h>
  25 #include <libkern/OSThermalNotification.h>
  26 #include <notify.h>
  27
  28 #define OSThermalStatusName "com.apple.system.thermalstatus"
  29
  30 const char * const kOSThermalNotificationName = OSThermalStatusName;
  31
  32 static const char * const kOSThermalMitigationNames[kOSThermalMitigationCount] = {
  33         OSThermalStatusName,
  34         "com.apple.system.thermalmitigation.70percenttorch",
  35         "com.apple.system.thermalmitigation.70percentbacklight",
  36         "com.apple.system.thermalmitigation.50percenttorch",
  37         "com.apple.system.thermalmitigation.50percentbacklight",
  38         "com.apple.system.thermalmitigation.disabletorch",
  39         "com.apple.system.thermalmitigation.25percentbacklight",
  40         "com.apple.system.thermalmitigation.disablemapshalo",
  41         "com.apple.system.thermalmitigation.appterminate",
  42         "com.apple.system.thermalmitigation.devicerestart",
  43         "com.apple.system.thermalmitigation.thermaltableready"
  44 };
  45
  46 static int tokens[kOSThermalMitigationCount];
  47 static dispatch_once_t predicates[kOSThermalMitigationCount];
  48 static bool thermalLevelsReady = false;
  49
  50 OSThermalNotificationLevel _OSThermalNotificationLevelForBehavior(int behavior)
  51 {
  52         uint64_t val = OSThermalNotificationLevelAny;
  53         if (behavior >= 0 && behavior < kOSThermalMitigationCount) {
  54                 dispatch_once(&predicates[behavior], ^{
  55                         (void)notify_register_check(kOSThermalMitigationNames[behavior], &tokens[behavior]);
  56                 });
  57                 (void)notify_get_state(tokens[behavior], &val);
  58         }
  59         return (OSThermalNotificationLevel)val;
  60 }
  61
  62 void _OSThermalNotificationSetLevelForBehavior(int level, int behavior)
  63 {
  64         uint64_t val = (uint64_t)level;
  65         if (behavior >= 0 && behavior < kOSThermalMitigationCount) {
  66                 dispatch_once(&predicates[behavior], ^{
  67                         (void)notify_register_check(kOSThermalMitigationNames[behavior], &tokens[behavior]);
  68                 });
  69                 (void)notify_set_state(tokens[behavior], val);
  70
  71                 // Note:
  72                 // - We are ready when we program in the appterminate value.
  73                 // - Assumes that user programs kOSThermalMitigationNone level less than
  74                 //   kOSThermalMitigationAppTerminate & kOSThermalMitigationDeviceRestart
  75                 if (behavior == kOSThermalMitigationAppTerminate) {
  76                         dispatch_once(&predicates[kOSThermalMitigationThermalTableReady], ^{
  77                                 (void)notify_register_check(kOSThermalMitigationNames[kOSThermalMitigationThermalTableReady], &tokens[kOSThermalMitigationThermalTableReady]);
  78                         });
  79                         (void)notify_set_state(tokens[kOSThermalMitigationThermalTableReady], kOSThermalMitigationCount);
  80                 }
  81         }
  82 }
  83
  84
  85 OSThermalNotificationLevel OSThermalNotificationCurrentLevel(void)
  86 {
  87         if (thermalLevelsReady) {
  88                 return _OSThermalNotificationLevelForBehavior(kOSThermalMitigationNone);
  89         }
  90
  91         uint64_t tableReady = 0;
  92
  93         dispatch_once(&predicates[kOSThermalMitigationThermalTableReady], ^{
  94                 (void)notify_register_check(kOSThermalMitigationNames[kOSThermalMitigationThermalTableReady], &tokens[kOSThermalMitigationThermalTableReady]);
  95         });
  96         (void)notify_get_state(tokens[kOSThermalMitigationThermalTableReady], &tableReady);
  97
  98         // If we are ready then optimize this so we don't call dispatch everytime.
  99         if (tableReady == kOSThermalMitigationCount) {
 100                 thermalLevelsReady = true;
 101                 return _OSThermalNotificationLevelForBehavior(kOSThermalMitigationNone);
 102         }
 103         else {
 104                 // Allow reset so we can dynamically change the table without thermal trap screen appearing.
 105                 thermalLevelsReady = false;
 106         }
 107
 108         // Not ready returns -1, which should not be equal or greater than any other thermal state.
 109         return OSThermalNotificationLevelAny;
 110 }