1 /* include/linux/wakelock.h
2 *
3 * Copyright (C) 2007-2008 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 #ifndef _LINUX_WAKELOCK_H
17 #define _LINUX_WAKELOCK_H
18
19 #include <linux/list.h>
20 #include <linux/ktime.h>
21
22 /* A wake_lock prevents the system from entering suspend or other low power
23 * states when active. If the type is set to WAKE_LOCK_SUSPEND, the wake_lock
24 * prevents a full system suspend. If the type is WAKE_LOCK_IDLE, low power
25 * states that cause large interrupt latencies or that disable a set of
26 * interrupts will not entered from idle until the wake_locks are released.
27 */
28
29 enum {
30 WAKE_LOCK_SUSPEND, /* Prevent suspend */
31 WAKE_LOCK_IDLE, /* Prevent low power idle */
32 WAKE_LOCK_TYPE_COUNT
33 };
34
35 struct wake_lock {
36 #ifdef CONFIG_HAS_WAKELOCK
37 struct list_head link;
38 int flags;
39 const char *name;
40 unsigned long expires;
41 #ifdef CONFIG_WAKELOCK_STAT
42 struct {
43 int count;
44 int expire_count;
45 int wakeup_count;
46 ktime_t total_time;
47 ktime_t prevent_suspend_time;
48 ktime_t max_time;
49 ktime_t last_time;
50 } stat;
51 #endif
52 #endif
53 };
54
55 #ifdef CONFIG_HAS_WAKELOCK
56
57 void wake_lock_init(struct wake_lock *lock, int type, const char *name);
58 void wake_lock_destroy(struct wake_lock *lock);
59 void wake_lock(struct wake_lock *lock);
60 void wake_lock_timeout(struct wake_lock *lock, long timeout);
61 void wake_unlock(struct wake_lock *lock);
62
63 /* wake_lock_active returns a non-zero value if the wake_lock is currently
64 * locked. If the wake_lock has a timeout, it does not check the timeout
65 * but if the timeout had aready been checked it will return 0.
66 */
67 int wake_lock_active(struct wake_lock *lock);
68
69 /* has_wake_lock returns 0 if no wake locks of the specified type are active,
70 * and non-zero if one or more wake locks are held. Specifically it returns
71 * -1 if one or more wake locks with no timeout are active or the
72 * number of jiffies until all active wake locks time out.
73 */
74 long has_wake_lock(int type);
75
76 #else
77
wake_lock_init(struct wake_lock * lock,int type,const char * name)78 static inline void wake_lock_init(struct wake_lock *lock, int type,
79 const char *name) {}
wake_lock_destroy(struct wake_lock * lock)80 static inline void wake_lock_destroy(struct wake_lock *lock) {}
wake_lock(struct wake_lock * lock)81 static inline void wake_lock(struct wake_lock *lock) {}
wake_lock_timeout(struct wake_lock * lock,long timeout)82 static inline void wake_lock_timeout(struct wake_lock *lock, long timeout) {}
wake_unlock(struct wake_lock * lock)83 static inline void wake_unlock(struct wake_lock *lock) {}
84
wake_lock_active(struct wake_lock * lock)85 static inline int wake_lock_active(struct wake_lock *lock) { return 0; }
has_wake_lock(int type)86 static inline long has_wake_lock(int type) { return 0; }
87
88 #endif
89
90 #endif
91
92