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 #include <TargetConditionals.h>
  29
  30 #define OSThermalPressureLevelName              "com.apple.system.thermalpressurelevel"
  31 const char * const kOSThermalNotificationPressureLevelName = OSThermalPressureLevelName;
  32
  33 #if TARGET_OS_IPHONE
  34 #define OSThermalAlert      "com.apple.system.thermalalert"
  35 #define OSThermalDecision   "com.apple.system.thermaldecision"
  36 #define OSThermalStatusName "com.apple.system.thermalstatus"
  37
  38 const char * const kOSThermalNotificationAlert    = OSThermalAlert;
  39 const char * const kOSThermalNotificationDecision = OSThermalDecision;
  40 const char * const kOSThermalNotificationName     = OSThermalStatusName;
  41
  42 static const char * const kOSThermalMitigationNames[kOSThermalMitigationCount] = {
  43         OSThermalStatusName,
  44         "com.apple.system.thermalmitigation.70percenttorch",
  45         "com.apple.system.thermalmitigation.70percentbacklight",
  46         "com.apple.system.thermalmitigation.50percenttorch",
  47         "com.apple.system.thermalmitigation.50percentbacklight",
  48         "com.apple.system.thermalmitigation.disabletorch",
  49         "com.apple.system.thermalmitigation.25percentbacklight",
  50         "com.apple.system.thermalmitigation.disablemapshalo",
  51         "com.apple.system.thermalmitigation.appterminate",
  52         "com.apple.system.thermalmitigation.devicerestart",
  53         "com.apple.system.thermalmitigation.thermaltableready"
  54 };
  55
  56 static int tokens[kOSThermalMitigationCount];
  57 static dispatch_once_t predicates[kOSThermalMitigationCount];
  58 static bool thermalLevelsReady = false;
  59
  60 OSThermalNotificationLevel _OSThermalNotificationLevelForBehavior(int behavior)
  61 {
  62         uint64_t val = OSThermalNotificationLevelAny;
  63         if (behavior >= 0 && behavior < kOSThermalMitigationCount) {
  64                 dispatch_once(&predicates[behavior], ^{
  65                         (void)notify_register_check(kOSThermalMitigationNames[behavior], &tokens[behavior]);
  66                 });
  67                 (void)notify_get_state(tokens[behavior], &val);
  68         }
  69         return (OSThermalNotificationLevel)val;
  70 }
  71
  72 void _OSThermalNotificationSetLevelForBehavior(int level, int behavior)
  73 {
  74         uint64_t val = (uint64_t)level;
  75         if (behavior >= 0 && behavior < kOSThermalMitigationCount) {
  76                 dispatch_once(&predicates[behavior], ^{
  77                         (void)notify_register_check(kOSThermalMitigationNames[behavior], &tokens[behavior]);
  78                 });
  79                 (void)notify_set_state(tokens[behavior], val);
  80
  81                 // Note:
  82                 // - We are ready when we program in the appterminate value.
  83                 // - Assumes that user programs kOSThermalMitigationNone level less than
  84                 //   kOSThermalMitigationAppTerminate & kOSThermalMitigationDeviceRestart
  85                 if (behavior == kOSThermalMitigationAppTerminate) {
  86                         dispatch_once(&predicates[kOSThermalMitigationThermalTableReady], ^{
  87                                 (void)notify_register_check(kOSThermalMitigationNames[kOSThermalMitigationThermalTableReady], &tokens[kOSThermalMitigationThermalTableReady]);
  88                         });
  89                         (void)notify_set_state(tokens[kOSThermalMitigationThermalTableReady], kOSThermalMitigationCount);
  90                 }
  91         }
  92 }
  93
  94
  95 OSThermalNotificationLevel OSThermalNotificationCurrentLevel(void)
  96 {
  97         if (thermalLevelsReady) {
  98                 return _OSThermalNotificationLevelForBehavior(kOSThermalMitigationNone);
  99         }
 100
 101         uint64_t tableReady = 0;
 102
 103         dispatch_once(&predicates[kOSThermalMitigationThermalTableReady], ^{
 104                 (void)notify_register_check(kOSThermalMitigationNames[kOSThermalMitigationThermalTableReady], &tokens[kOSThermalMitigationThermalTableReady]);
 105         });
 106         (void)notify_get_state(tokens[kOSThermalMitigationThermalTableReady], &tableReady);
 107
 108         // If we are ready then optimize this so we don't call dispatch everytime.
 109         if (tableReady == kOSThermalMitigationCount) {
 110                 thermalLevelsReady = true;
 111                 return _OSThermalNotificationLevelForBehavior(kOSThermalMitigationNone);
 112         }
 113         else {
 114                 // Allow reset so we can dynamically change the table without thermal trap screen appearing.
 115                 thermalLevelsReady = false;
 116         }
 117
 118         // Not ready returns -1, which should not be equal or greater than any other thermal state.
 119         return OSThermalNotificationLevelAny;
 120 }
 121
 122 #endif // TARGET_OS_IPHONE