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"
31const 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
38const char * const kOSThermalNotificationAlert    = OSThermalAlert;
39const char * const kOSThermalNotificationDecision = OSThermalDecision;
40const char * const kOSThermalNotificationName     = OSThermalStatusName;
41
42static 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
56static int tokens[kOSThermalMitigationCount];
57static dispatch_once_t predicates[kOSThermalMitigationCount];
58static bool thermalLevelsReady = false;
59
60OSThermalNotificationLevel _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
72void _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
95OSThermalNotificationLevel 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
123