/*
   *  pm.h - Power management interface
   *
   *  Copyright (C) 2000 Andrew Henroid
   *
   *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  
  #ifndef _LINUX_PM_H
  #define _LINUX_PM_H
  
  #ifdef __KERNEL__

  #include <linux/list.h>
  #include <asm/atomic.h>
  
  /*
   * Power management requests... these are passed to pm_send_all() and friends.
   *
   * these functions are old and deprecated, see below.
   */
  typedef int __bitwise pm_request_t;
  
  #define PM_SUSPEND	((__force pm_request_t) 1)	/* enter D1-D3 */
  #define PM_RESUME	((__force pm_request_t) 2)	/* enter D0 */
  
  
  /*
   * Device types... these are passed to pm_register
   */
  typedef int __bitwise pm_dev_t;
  
  #define PM_UNKNOWN_DEV	((__force pm_dev_t) 0)	/* generic */
  #define PM_SYS_DEV	((__force pm_dev_t) 1)	/* system device (fan, KB controller, ...) */
  #define PM_PCI_DEV	((__force pm_dev_t) 2)	/* PCI device */
  #define PM_USB_DEV	((__force pm_dev_t) 3)	/* USB device */
  #define PM_SCSI_DEV	((__force pm_dev_t) 4)	/* SCSI device */
  #define PM_ISA_DEV	((__force pm_dev_t) 5)	/* ISA device */
  #define	PM_MTD_DEV	((__force pm_dev_t) 6)	/* Memory Technology Device */
  
  /*
   * System device hardware ID (PnP) values
   */
  enum
  {
  	PM_SYS_UNKNOWN = 0x00000000, /* generic */
  	PM_SYS_KBC =	 0x41d00303, /* keyboard controller */
  	PM_SYS_COM =	 0x41d00500, /* serial port */
  	PM_SYS_IRDA =	 0x41d00510, /* IRDA controller */
  	PM_SYS_FDC =	 0x41d00700, /* floppy controller */
  	PM_SYS_VGA =	 0x41d00900, /* VGA controller */
  	PM_SYS_PCMCIA =	 0x41d00e00, /* PCMCIA controller */
  };
  
  /*
   * Device identifier
   */
  #define PM_PCI_ID(dev) ((dev)->bus->number << 16 | (dev)->devfn)
  
  /*
   * Request handler callback
   */
  struct pm_dev;
  
  typedef int (*pm_callback)(struct pm_dev *dev, pm_request_t rqst, void *data);
  
  /*
   * Dynamic device information
   */
  struct pm_dev
  {
  	pm_dev_t	 type;
  	unsigned long	 id;
  	pm_callback	 callback;
  	void		*data;
  
  	unsigned long	 flags;
  	unsigned long	 state;
  	unsigned long	 prev_state;
  
  	struct list_head entry;
  };

  /* Functions above this comment are list-based old-style power
   * managment. Please avoid using them.  */
  
  /*
   * Callbacks for platform drivers to implement.
   */
  extern void (*pm_idle)(void);
  extern void (*pm_power_off)(void);

  extern void (*pm_power_off_prepare)(void);

  
  typedef int __bitwise suspend_state_t;
  
  #define PM_SUSPEND_ON		((__force suspend_state_t) 0)
  #define PM_SUSPEND_STANDBY	((__force suspend_state_t) 1)
  #define PM_SUSPEND_MEM		((__force suspend_state_t) 3)

  #define PM_SUSPEND_MAX		((__force suspend_state_t) 4)

  /**

   * struct pm_ops - Callbacks for managing platform dependent system sleep
   *	states.

   *

   * @valid: Callback to determine if given system sleep state is supported by
   *	the platform.
   *	Valid (ie. supported) states are advertised in /sys/power/state.  Note
   *	that it still may be impossible to enter given system sleep state if the
   *	conditions aren't right.
   *	There is the %pm_valid_only_mem function available that can be assigned
   *	to this if the platform only supports mem sleep.

   *

   * @set_target: Tell the platform which system sleep state is going to be
   *	entered.
   *	@set_target() is executed right prior to suspending devices.  The
   *	information conveyed to the platform code by @set_target() should be
   *	disregarded by the platform as soon as @finish() is executed and if
   *	@prepare() fails.  If @set_target() fails (ie. returns nonzero),
   *	@prepare(), @enter() and @finish() will not be called by the PM core.
   *	This callback is optional.  However, if it is implemented, the argument
   *	passed to @prepare(), @enter() and @finish() is meaningless and should
   *	be ignored.

   *

   * @prepare: Prepare the platform for entering the system sleep state indicated
   *	by @set_target() or represented by the argument if @set_target() is not
   *	implemented.
   *	@prepare() is called right after devices have been suspended (ie. the
   *	appropriate .suspend() method has been executed for each device) and
   *	before the nonboot CPUs are disabled (it is executed with IRQs enabled).
   *	This callback is optional.  It returns 0 on success or a negative
   *	error code otherwise, in which case the system cannot enter the desired
   *	sleep state (@enter() and @finish() will not be called in that case).
   *
   * @enter: Enter the system sleep state indicated by @set_target() or
   *	represented by the argument if @set_target() is not implemented.
   *	This callback is mandatory.  It returns 0 on success or a negative
   *	error code otherwise, in which case the system cannot enter the desired
   *	sleep state.
   *
   * @finish: Called when the system has just left a sleep state, right after
   *	the nonboot CPUs have been enabled and before devices are resumed (it is
   *	executed with IRQs enabled).  If @set_target() is not implemented, the
   *	argument represents the sleep state being left.
   *	This callback is optional, but should be implemented by the platforms
   *	that implement @prepare().  If implemented, it is always called after
   *	@enter() (even if @enter() fails).

   */

  struct pm_ops {

  	int (*valid)(suspend_state_t state);

  	int (*set_target)(suspend_state_t state);

  	int (*prepare)(suspend_state_t state);
  	int (*enter)(suspend_state_t state);
  	int (*finish)(suspend_state_t state);
  };

  #ifdef CONFIG_SUSPEND

  extern struct pm_ops *pm_ops;

  /**
   * pm_set_ops - set platform dependent power management ops
   * @pm_ops: The new power management operations to set.
   */
  extern void pm_set_ops(struct pm_ops *pm_ops);

  extern int pm_valid_only_mem(suspend_state_t state);

  /**
   * arch_suspend_disable_irqs - disable IRQs for suspend
   *
   * Disables IRQs (in the default case). This is a weak symbol in the common
   * code and thus allows architectures to override it if more needs to be
   * done. Not called for suspend to disk.
   */
  extern void arch_suspend_disable_irqs(void);
  
  /**
   * arch_suspend_enable_irqs - enable IRQs after suspend
   *
   * Enables IRQs (in the default case). This is a weak symbol in the common
   * code and thus allows architectures to override it if more needs to be
   * done. Not called for suspend to disk.
   */
  extern void arch_suspend_enable_irqs(void);

  extern int pm_suspend(suspend_state_t state);

  #else /* !CONFIG_SUSPEND */
  #define suspend_valid_only_mem	NULL
  
  static inline void pm_set_ops(struct pm_ops *pm_ops) {}
  static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; }
  #endif /* !CONFIG_SUSPEND */

  /*
   * Device power management
   */
  
  struct device;

  typedef struct pm_message {
  	int event;
  } pm_message_t;

  
  /*

   * Several driver power state transitions are externally visible, affecting
   * the state of pending I/O queues and (for drivers that touch hardware)
   * interrupts, wakeups, DMA, and other hardware state.  There may also be
   * internal transitions to various low power modes, which are transparent
   * to the rest of the driver stack (such as a driver that's ON gating off
   * clocks which are not in active use).

   *

   * One transition is triggered by resume(), after a suspend() call; the
   * message is implicit:
   *
   * ON		Driver starts working again, responding to hardware events
   * 		and software requests.  The hardware may have gone through
   * 		a power-off reset, or it may have maintained state from the
   * 		previous suspend() which the driver will rely on while
   * 		resuming.  On most platforms, there are no restrictions on
   * 		availability of resources like clocks during resume().
   *
   * Other transitions are triggered by messages sent using suspend().  All
   * these transitions quiesce the driver, so that I/O queues are inactive.
   * That commonly entails turning off IRQs and DMA; there may be rules
   * about how to quiesce that are specific to the bus or the device's type.
   * (For example, network drivers mark the link state.)  Other details may
   * differ according to the message:
   *
   * SUSPEND	Quiesce, enter a low power device state appropriate for
   * 		the upcoming system state (such as PCI_D3hot), and enable
   * 		wakeup events as appropriate.
   *
   * FREEZE	Quiesce operations so that a consistent image can be saved;
   * 		but do NOT otherwise enter a low power device state, and do
   * 		NOT emit system wakeup events.
   *
   * PRETHAW	Quiesce as if for FREEZE; additionally, prepare for restoring
   * 		the system from a snapshot taken after an earlier FREEZE.
   * 		Some drivers will need to reset their hardware state instead
   * 		of preserving it, to ensure that it's never mistaken for the
   * 		state which that earlier snapshot had set up.
   *
   * A minimally power-aware driver treats all messages as SUSPEND, fully
   * reinitializes its device during resume() -- whether or not it was reset
   * during the suspend/resume cycle -- and can't issue wakeup events.
   *
   * More power-aware drivers may also use low power states at runtime as
   * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
   * be able to use wakeup events to exit from runtime low-power states,
   * or from system low-power states such as standby or suspend-to-RAM.

   */

  #define PM_EVENT_ON 0
  #define PM_EVENT_FREEZE 1
  #define PM_EVENT_SUSPEND 2

  #define PM_EVENT_PRETHAW 3

  
  #define PMSG_FREEZE	((struct pm_message){ .event = PM_EVENT_FREEZE, })

  #define PMSG_PRETHAW	((struct pm_message){ .event = PM_EVENT_PRETHAW, })

  #define PMSG_SUSPEND	((struct pm_message){ .event = PM_EVENT_SUSPEND, })
  #define PMSG_ON		((struct pm_message){ .event = PM_EVENT_ON, })

  
  struct dev_pm_info {
  	pm_message_t		power_state;

  	unsigned		can_wakeup:1;

  #ifdef	CONFIG_PM_SLEEP

  	unsigned		should_wakeup:1;

  	struct list_head	entry;
  #endif
  };

  extern int device_power_down(pm_message_t state);
  extern void device_power_up(void);
  extern void device_resume(void);

  #ifdef CONFIG_PM_SLEEP

  extern int device_suspend(pm_message_t state);

  extern int device_prepare_suspend(pm_message_t state);

  
  #define device_set_wakeup_enable(dev,val) \
  	((dev)->power.should_wakeup = !!(val))
  #define device_may_wakeup(dev) \
  	(device_can_wakeup(dev) && (dev)->power.should_wakeup)

  extern void __suspend_report_result(const char *function, void *fn, int ret);
  
  #define suspend_report_result(fn, ret)					\
  	do {								\
  		__suspend_report_result(__FUNCTION__, fn, ret);		\
  	} while (0)

  /*
   * Platform hook to activate device wakeup capability, if that's not already
   * handled by enable_irq_wake() etc.
   * Returns zero on success, else negative errno
   */
  extern int (*platform_enable_wakeup)(struct device *dev, int is_on);
  
  static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
  {
  	if (platform_enable_wakeup)
  		return (*platform_enable_wakeup)(dev, is_on);
  	return 0;
  }

  #else /* !CONFIG_PM_SLEEP */

  static inline int device_suspend(pm_message_t state)
  {
  	return 0;
  }

  
  #define device_set_wakeup_enable(dev,val)	do{}while(0)
  #define device_may_wakeup(dev)			(0)

  #define suspend_report_result(fn, ret) do { } while (0)

  static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
  {

  	return 0;

  }

  #endif /* !CONFIG_PM_SLEEP */

  /* changes to device_may_wakeup take effect on the next pm state change.
   * by default, devices should wakeup if they can.
   */
  #define device_can_wakeup(dev) \
  	((dev)->power.can_wakeup)
  #define device_init_wakeup(dev,val) \
  	do { \
  		device_can_wakeup(dev) = !!(val); \
  		device_set_wakeup_enable(dev,val); \
  	} while(0)

  #endif /* __KERNEL__ */
  
  #endif /* _LINUX_PM_H */