1 /* kernel/power/earlysuspend.c
2 *
3 * Copyright (C) 2005-2008 Google, Inc.
4 *
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 */
15
16 #include <linux/earlysuspend.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
19 #include <linux/rtc.h>
20 #include <linux/syscalls.h> /* sys_sync */
21 #include <linux/wakelock.h>
22 #include <linux/workqueue.h>
23
24 #include "power.h"
25
26 enum {
27 DEBUG_USER_STATE = 1U << 0,
28 DEBUG_SUSPEND = 1U << 2,
29 };
30 static int debug_mask = DEBUG_USER_STATE;
31 module_param_named(debug_mask, debug_mask, int, S_IRUGO | S_IWUSR | S_IWGRP);
32
33 static DEFINE_MUTEX(early_suspend_lock);
34 static LIST_HEAD(early_suspend_handlers);
35 static void early_suspend(struct work_struct *work);
36 static void late_resume(struct work_struct *work);
37 static DECLARE_WORK(early_suspend_work, early_suspend);
38 static DECLARE_WORK(late_resume_work, late_resume);
39 static DEFINE_SPINLOCK(state_lock);
40 enum {
41 SUSPEND_REQUESTED = 0x1,
42 SUSPENDED = 0x2,
43 SUSPEND_REQUESTED_AND_SUSPENDED = SUSPEND_REQUESTED | SUSPENDED,
44 };
45 static int state;
46
register_early_suspend(struct early_suspend * handler)47 void register_early_suspend(struct early_suspend *handler)
48 {
49 struct list_head *pos;
50
51 mutex_lock(&early_suspend_lock);
52 list_for_each(pos, &early_suspend_handlers) {
53 struct early_suspend *e;
54 e = list_entry(pos, struct early_suspend, link);
55 if (e->level > handler->level)
56 break;
57 }
58 list_add_tail(&handler->link, pos);
59 if ((state & SUSPENDED) && handler->suspend)
60 handler->suspend(handler);
61 mutex_unlock(&early_suspend_lock);
62 }
63 EXPORT_SYMBOL(register_early_suspend);
64
unregister_early_suspend(struct early_suspend * handler)65 void unregister_early_suspend(struct early_suspend *handler)
66 {
67 mutex_lock(&early_suspend_lock);
68 list_del(&handler->link);
69 mutex_unlock(&early_suspend_lock);
70 }
71 EXPORT_SYMBOL(unregister_early_suspend);
72
early_suspend(struct work_struct * work)73 static void early_suspend(struct work_struct *work)
74 {
75 struct early_suspend *pos;
76 unsigned long irqflags;
77 int abort = 0;
78
79 mutex_lock(&early_suspend_lock);
80 spin_lock_irqsave(&state_lock, irqflags);
81 if (state == SUSPEND_REQUESTED)
82 state |= SUSPENDED;
83 else
84 abort = 1;
85 spin_unlock_irqrestore(&state_lock, irqflags);
86
87 if (abort) {
88 if (debug_mask & DEBUG_SUSPEND)
89 pr_info("early_suspend: abort, state %d\n", state);
90 mutex_unlock(&early_suspend_lock);
91 goto abort;
92 }
93
94 if (debug_mask & DEBUG_SUSPEND)
95 pr_info("early_suspend: call handlers\n");
96 list_for_each_entry(pos, &early_suspend_handlers, link) {
97 if (pos->suspend != NULL)
98 pos->suspend(pos);
99 }
100 mutex_unlock(&early_suspend_lock);
101
102 if (debug_mask & DEBUG_SUSPEND)
103 pr_info("early_suspend: sync\n");
104
105 sys_sync();
106 abort:
107 spin_lock_irqsave(&state_lock, irqflags);
108 if (state == SUSPEND_REQUESTED_AND_SUSPENDED)
109 wake_unlock(&main_wake_lock);
110 spin_unlock_irqrestore(&state_lock, irqflags);
111 }
112
late_resume(struct work_struct * work)113 static void late_resume(struct work_struct *work)
114 {
115 struct early_suspend *pos;
116 unsigned long irqflags;
117 int abort = 0;
118
119 mutex_lock(&early_suspend_lock);
120 spin_lock_irqsave(&state_lock, irqflags);
121 if (state == SUSPENDED)
122 state &= ~SUSPENDED;
123 else
124 abort = 1;
125 spin_unlock_irqrestore(&state_lock, irqflags);
126
127 if (abort) {
128 if (debug_mask & DEBUG_SUSPEND)
129 pr_info("late_resume: abort, state %d\n", state);
130 goto abort;
131 }
132 if (debug_mask & DEBUG_SUSPEND)
133 pr_info("late_resume: call handlers\n");
134 list_for_each_entry_reverse(pos, &early_suspend_handlers, link)
135 if (pos->resume != NULL)
136 pos->resume(pos);
137 if (debug_mask & DEBUG_SUSPEND)
138 pr_info("late_resume: done\n");
139 abort:
140 mutex_unlock(&early_suspend_lock);
141 }
142
request_suspend_state(suspend_state_t new_state)143 void request_suspend_state(suspend_state_t new_state)
144 {
145 unsigned long irqflags;
146 int old_sleep;
147
148 spin_lock_irqsave(&state_lock, irqflags);
149 old_sleep = state & SUSPEND_REQUESTED;
150 if (debug_mask & DEBUG_USER_STATE) {
151 struct timespec ts;
152 struct rtc_time tm;
153 getnstimeofday(&ts);
154 rtc_time_to_tm(ts.tv_sec, &tm);
155 pr_info("request_suspend_state: %s (%d->%d) at %lld "
156 "(%d-%02d-%02d %02d:%02d:%02d.%09lu UTC)\n",
157 new_state != PM_SUSPEND_ON ? "sleep" : "wakeup",
158 requested_suspend_state, new_state,
159 ktime_to_ns(ktime_get()),
160 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
161 tm.tm_hour, tm.tm_min, tm.tm_sec, ts.tv_nsec);
162 }
163 if (!old_sleep && new_state != PM_SUSPEND_ON) {
164 state |= SUSPEND_REQUESTED;
165 queue_work(suspend_work_queue, &early_suspend_work);
166 } else if (old_sleep && new_state == PM_SUSPEND_ON) {
167 state &= ~SUSPEND_REQUESTED;
168 wake_lock(&main_wake_lock);
169 queue_work(suspend_work_queue, &late_resume_work);
170 }
171 requested_suspend_state = new_state;
172 spin_unlock_irqrestore(&state_lock, irqflags);
173 }
174
get_suspend_state(void)175 suspend_state_t get_suspend_state(void)
176 {
177 return requested_suspend_state;
178 }
179