aboutsummaryrefslogtreecommitdiff
path: root/backends/platform/psp/powerman.h
blob: 77cfb26720189a0b98fc4aacc6cb899041a5d841 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */

#ifndef POWERMAN_H
#define POWERMAN_H

#include "backends/platform/psp/thread.h"
#include "common/singleton.h"
#include "common/list.h"

/*
 *  Implement this class (interface) if you want to use PowerManager's suspend callback functionality
 *
 */
class Suspendable {
public:
	virtual ~Suspendable() {}
	virtual int suspend() = 0;
	virtual int resume() = 0;
};

/******************************************************************************************************
*
*  This class will call a Suspendable when the PSP goes to suspend/resumes. It also provides the ability to block
*  a thread when the PSP is going to suspend/suspending, and to wake it up when the PSP is resumed.
*	This ability is very useful for managing the PSPIoStream class, but may be found useful by other classes as well.
*
*******************************************************************************************************/
class PowerManager: public Common::Singleton<PowerManager> {

public:
	int blockOnSuspend();								/* block if suspending */
	bool beginCriticalSection();	/* Use a critical section to block (if suspend was already pressed) */
	void endCriticalSection();							/* and to prevent the PSP from suspending in a particular section */
	bool registerForSuspend(Suspendable *item);			/* register to be called to suspend/resume */
	bool unregisterForSuspend(Suspendable *item);		/* remove from suspend/resume list */
	void suspend();									/* callback to have all items in list suspend */
	void resume();									/* callback to have all items in list resume */
	// Functions for pausing the engine
	void pollPauseEngine();							/* Poll whether the engine should be paused */

	enum {
		Error = -1,
		NotBlocked = 0,
		Blocked = 1
	};

	enum PauseState {
		UNPAUSED = 0,
		PAUSING,
		PAUSED
	};

private:
	friend class Common::Singleton<PowerManager>;
	PowerManager();
	~PowerManager();

	Common::List<Suspendable *> _suspendList;		// list to register in

	volatile bool _pauseFlag;						// For pausing, which is before suspending
	volatile bool _pauseFlagOld;					// Save the last state of the flag while polling
	volatile PauseState _pauseClientState;			// Pause state of the target

	volatile bool _suspendFlag;						// protected variable
	PspMutex _flagMutex;							// mutex to access access flag
	PspMutex _listMutex;							// mutex to access Suspendable list
	PspCondition _threadSleep;						// signal to synchronize accessing threads
	PspCondition _pmSleep;							// signal to wake up the PM from a critical section
	volatile int _criticalCounter;					// Counter of how many threads are in a critical section
	int _error;										// error code - PM can't talk to us. For debugging
	volatile int _PMStatus;							// What the PM is doing. for debugging

	// States for PM to be in (used for debugging)
	enum PMState {
		kInitDone = 1,
		kDestroyPM = 2,
		kWaitForClientPause = 3,
		kWaitForClientToFinishPausing = 4,
		kGettingFlagMutexSuspend = 5,
		kGotFlagMutexSuspend = 6,
		kWaitCritSectionSuspend = 7,
		kDoneWaitingCritSectionSuspend = 8,
		kGettingListMutexSuspend = 9,
		kIteratingListSuspend = 10,
		kDoneIteratingListSuspend = 11,
		kDoneSuspend = 12,
		kDonePowerUnlock,
		kBeginResume,
		kCheckingPauseFlag,
		kGettingListMutexResume,
		kIteratingListResume,
		kDoneIteratingListResume,
		kGettingFlagMutexResume,
		kGotFlagMutexResume,
		kSignalSuspendedThreadsResume,
		kDoneSignallingSuspendedThreadsResume,
		kDoneResume
	};

	volatile int _listCounter;						/* How many people are in the list - just for debugging */

	void debugPM();									/* print info about the PM */

public:
	int getPMStatus() const { return _PMStatus; }

};

// For easy access
#define PowerMan	PowerManager::instance()

#endif /* POWERMAN_H */