summaryrefslogtreecommitdiff
path: root/kernel/power/earlysuspend.c
blob: 84bed51dcdce79503d718186775e690560d4637b (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
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
/* kernel/power/earlysuspend.c
 *
 * Copyright (C) 2005-2008 Google, Inc.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * 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.
 *
 */

#include <linux/earlysuspend.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/rtc.h>
#include <linux/syscalls.h> /* sys_sync */
#include <linux/wakelock.h>
#include <linux/workqueue.h>

#include "power.h"

enum {
	DEBUG_USER_STATE = 1U << 0,
	DEBUG_SUSPEND = 1U << 2,
};
static int debug_mask = DEBUG_USER_STATE;
module_param_named(debug_mask, debug_mask, int, S_IRUGO | S_IWUSR | S_IWGRP);

static DEFINE_MUTEX(early_suspend_lock);
static LIST_HEAD(early_suspend_handlers);
static void early_suspend(struct work_struct *work);
static void late_resume(struct work_struct *work);
static DECLARE_WORK(early_suspend_work, early_suspend);
static DECLARE_WORK(late_resume_work, late_resume);
static DEFINE_SPINLOCK(state_lock);
enum {
	SUSPEND_REQUESTED = 0x1,
	SUSPENDED = 0x2,
	SUSPEND_REQUESTED_AND_SUSPENDED = SUSPEND_REQUESTED | SUSPENDED,
};
static int state;

void register_early_suspend(struct early_suspend *handler)
{
	struct list_head *pos;

	mutex_lock(&early_suspend_lock);
	list_for_each(pos, &early_suspend_handlers) {
		struct early_suspend *e;
		e = list_entry(pos, struct early_suspend, link);
		if (e->level > handler->level)
			break;
	}
	list_add_tail(&handler->link, pos);
	if ((state & SUSPENDED) && handler->suspend)
		handler->suspend(handler);
	mutex_unlock(&early_suspend_lock);
}
EXPORT_SYMBOL(register_early_suspend);

void unregister_early_suspend(struct early_suspend *handler)
{
	mutex_lock(&early_suspend_lock);
	list_del(&handler->link);
	mutex_unlock(&early_suspend_lock);
}
EXPORT_SYMBOL(unregister_early_suspend);

static void early_suspend(struct work_struct *work)
{
	struct early_suspend *pos;
	unsigned long irqflags;
	int abort = 0;

	mutex_lock(&early_suspend_lock);
	spin_lock_irqsave(&state_lock, irqflags);
	if (state == SUSPEND_REQUESTED)
		state |= SUSPENDED;
	else
		abort = 1;
	spin_unlock_irqrestore(&state_lock, irqflags);

	if (abort) {
		if (debug_mask & DEBUG_SUSPEND)
			pr_info("early_suspend: abort, state %d\n", state);
		mutex_unlock(&early_suspend_lock);
		goto abort;
	}

	if (debug_mask & DEBUG_SUSPEND)
		pr_info("early_suspend: call handlers\n");
	list_for_each_entry(pos, &early_suspend_handlers, link) {
		if (pos->suspend != NULL)
			pos->suspend(pos);
	}
	mutex_unlock(&early_suspend_lock);

	if (debug_mask & DEBUG_SUSPEND)
		pr_info("early_suspend: sync\n");

	sys_sync();
abort:
	spin_lock_irqsave(&state_lock, irqflags);
	if (state == SUSPEND_REQUESTED_AND_SUSPENDED)
		wake_unlock(&main_wake_lock);
	spin_unlock_irqrestore(&state_lock, irqflags);
}

static void late_resume(struct work_struct *work)
{
	struct early_suspend *pos;
	unsigned long irqflags;
	int abort = 0;

	mutex_lock(&early_suspend_lock);
	spin_lock_irqsave(&state_lock, irqflags);
	if (state == SUSPENDED)
		state &= ~SUSPENDED;
	else
		abort = 1;
	spin_unlock_irqrestore(&state_lock, irqflags);

	if (abort) {
		if (debug_mask & DEBUG_SUSPEND)
			pr_info("late_resume: abort, state %d\n", state);
		goto abort;
	}
	if (debug_mask & DEBUG_SUSPEND)
		pr_info("late_resume: call handlers\n");
	list_for_each_entry_reverse(pos, &early_suspend_handlers, link)
		if (pos->resume != NULL)
			pos->resume(pos);
	if (debug_mask & DEBUG_SUSPEND)
		pr_info("late_resume: done\n");
abort:
	mutex_unlock(&early_suspend_lock);
}

void request_suspend_state(suspend_state_t new_state)
{
	unsigned long irqflags;
	int old_sleep;

	spin_lock_irqsave(&state_lock, irqflags);
	old_sleep = state & SUSPEND_REQUESTED;
	if (debug_mask & DEBUG_USER_STATE) {
		struct timespec ts;
		struct rtc_time tm;
		getnstimeofday(&ts);
		rtc_time_to_tm(ts.tv_sec, &tm);
		pr_info("request_suspend_state: %s (%d->%d) at %lld "
			"(%d-%02d-%02d %02d:%02d:%02d.%09lu UTC)\n",
			new_state != PM_SUSPEND_ON ? "sleep" : "wakeup",
			requested_suspend_state, new_state,
			ktime_to_ns(ktime_get()),
			tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
			tm.tm_hour, tm.tm_min, tm.tm_sec, ts.tv_nsec);
	}
	if (!old_sleep && new_state != PM_SUSPEND_ON) {
		state |= SUSPEND_REQUESTED;
		queue_work(suspend_work_queue, &early_suspend_work);
	} else if (old_sleep && new_state == PM_SUSPEND_ON) {
		state &= ~SUSPEND_REQUESTED;
		wake_lock(&main_wake_lock);
		queue_work(suspend_work_queue, &late_resume_work);
	}
	requested_suspend_state = new_state;
	spin_unlock_irqrestore(&state_lock, irqflags);
}

suspend_state_t get_suspend_state(void)
{
	return requested_suspend_state;
}