drivers/staging/dream/include/linux/wakelock.h

   1 /* drivers/staging/dream/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
  78 static inline void wake_lock_init(struct wake_lock *lock, int type,
  79                                         const char *name) {}
  80 static inline void wake_lock_destroy(struct wake_lock *lock) {}
  81 static inline void wake_lock(struct wake_lock *lock) {}
  82 static inline void wake_lock_timeout(struct wake_lock *lock, long timeout) {}
  83 static inline void wake_unlock(struct wake_lock *lock) {}
  84
  85 static inline int wake_lock_active(struct wake_lock *lock) { return 0; }
  86 static inline long has_wake_lock(int type) { return 0; }
  87
  88 #endif
  89
  90 #endif
  91