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/*
* 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
#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/timer.h>
#include <linux/completion.h>
/*
* Callbacks for platform drivers to implement.
*/
extern void (*pm_power_off)(void);
extern void (*pm_power_off_prepare)(void);
struct device; /* we have a circular dep with device.h */
#ifdef CONFIG_VT_CONSOLE_SLEEP
extern void pm_vt_switch_required(struct device *dev, bool required);
extern void pm_vt_switch_unregister(struct device *dev);
#else
static inline void pm_vt_switch_required(struct device *dev, bool required)
{
}
static inline void pm_vt_switch_unregister(struct device *dev)
{
}
#endif /* CONFIG_VT_CONSOLE_SLEEP */
/*
* Device power management
*/
struct device;
#ifdef CONFIG_PM
extern const char power_group_name[]; /* = "power" */
#else
#define power_group_name NULL
#endif
typedef struct pm_message {
int event;
} pm_message_t;
/**
* struct dev_pm_ops - device PM callbacks
*
* Several device 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).
*
* The externally visible transitions are handled with the help of callbacks
* included in this structure in such a way that two levels of callbacks are
* involved. First, the PM core executes callbacks provided by PM domains,
* device types, classes and bus types. They are the subsystem-level callbacks
* supposed to execute callbacks provided by device drivers, although they may
* choose not to do that. If the driver callbacks are executed, they have to
* collaborate with the subsystem-level callbacks to achieve the goals
* appropriate for the given system transition, given transition phase and the
* subsystem the device belongs to.
*
* @prepare: The principal role of this callback is to prevent new children of
* the device from being registered after it has returned (the driver's
* subsystem and generally the rest of the kernel is supposed to prevent
* new calls to the probe method from being made too once @prepare() has
* succeeded). If @prepare() detects a situation it cannot handle (e.g.
* registration of a child already in progress), it may return -EAGAIN, so
* that the PM core can execute it once again (e.g. after a new child has
* been registered) to recover from the race condition.
* This method is executed for all kinds of suspend transitions and is
* followed by one of the suspend callbacks: @suspend(), @freeze(), or
* @poweroff(). The PM core executes subsystem-level @prepare() for all
* devices before starting to invoke suspend callbacks for any of them, so
* generally devices may be assumed to be functional or to respond to
* runtime resume requests while @prepare() is being executed. However,
* device drivers may NOT assume anything about the availability of user
* space at that time and it is NOT valid to request firmware from within
* @prepare() (it's too late to do that). It also is NOT valid to allocate
* substantial amounts of memory from @prepare() in the GFP_KERNEL mode.
* [To work around these limitations, drivers may register suspend and
* hibernation notifiers to be executed before the freezing of tasks.]
*
* @complete: Undo the changes made by @prepare(). This method is executed for
* all kinds of resume transitions, following one of the resume callbacks:
* @resume(), @thaw(), @restore(). Also called if the state transition
* fails before the driver's suspend callback: @suspend(), @freeze() or
* @poweroff(), can be executed (e.g. if the suspend callback fails for one
* of the other devices that the PM core has unsuccessfully attempted to
* suspend earlier).
* The PM core executes subsystem-level @complete() after it has executed
* the appropriate resume callbacks for all devices.
*
* @suspend: Executed before putting the system into a sleep state in which the
* contents of main memory are preserved. The exact action to perform
* depends on the device's subsystem (PM domain, device type, class or bus
* type), but generally the device must be quiescent after subsystem-level
* @suspend() has returned, so that it doesn't do any I/O or DMA.
* Subsystem-level @suspend() is executed for all devices after invoking
* subsystem-level @prepare() for all of them.
*
* @suspend_late: Continue operations started by @suspend(). For a number of
* devices @suspend_late() may point to the same callback routine as the
* runtime suspend callback.
*
* @resume: Executed after waking the system up from a sleep state in which the
* contents of main memory were preserved. The exact action to perform
* depends on the device's subsystem, but generally the driver is expected
* to start working again, responding to hardware events and software
* requests (the device itself may be left in a low-power state, waiting
* for a runtime resume to occur). The state of the device at the time its
* driver's @resume() callback is run depends on the platform and subsystem
* the device belongs to. On most platforms, there are no restrictions on
* availability of resources like clocks during @resume().
* Subsystem-level @resume() is executed for all devices after invoking
* subsystem-level @resume_noirq() for all of them.
*
* @resume_early: Prepare to execute @resume(). For a number of devices
* @resume_early() may point to the same callback routine as the runtime
* resume callback.
*
* @freeze: Hibernation-specific, executed before creating a hibernation image.
* Analogous to @suspend(), but it should not enable the device to signal
* wakeup events or change its power state. The majority of subsystems
* (with the notable exception of the PCI bus type) expect the driver-level
* @freeze() to save the device settings in memory to be used by @restore()
* during the subsequent resume from hibernation.
* Subsystem-level @freeze() is executed for all devices after invoking
* subsystem-level @prepare() for all of them.
*
* @freeze_late: Continue operations started by @freeze(). Analogous to
* @suspend_late(), but it should not enable the device to signal wakeup
* events or change its power state.
*
* @thaw: Hibernation-specific, executed after creating a hibernation image OR
* if the creation of an image has failed. Also executed after a failing
* attempt to restore the contents of main memory from such an image.
* Undo the changes made by the preceding @freeze(), so the device can be
* operated in the same way as immediately before the call to @freeze().
* Subsystem-level @thaw() is executed for all devices after invoking
* subsystem-level @thaw_noirq() for all of them. It also may be executed
* directly after @freeze() in case of a transition error.
*
* @thaw_early: Prepare to execute @thaw(). Undo the changes made by the
* preceding @freeze_late().
*
* @poweroff: Hibernation-specific, executed after saving a hibernation image.
* Analogous to @suspend(), but it need not save the device's settings in
* memory.
* Subsystem-level @poweroff() is executed for all devices after invoking
* subsystem-level @prepare() for all of them.
*
* @poweroff_late: Continue operations started by @poweroff(). Analogous to
* @suspend_late(), but it need not save the device's settings in memory.
*
* @restore: Hibernation-specific, executed after restoring the contents of main
* memory from a hibernation image, analogous to @resume().
*
* @restore_early: Prepare to execute @restore(), analogous to @resume_early().
*
* @suspend_noirq: Complete the actions started by @suspend(). Carry out any
* additional operations required for suspending the device that might be
* racing with its driver's interrupt handler, which is guaranteed not to
* run while @suspend_noirq() is being executed.
* It generally is expected that the device will be in a low-power state
* (appropriate for the target system sleep state) after subsystem-level
* @suspend_noirq() has returned successfully. If the device can generate
* system wakeup signals and is enabled to wake up the system, it should be
* configured to do so at that time. However, depending on the platform
* and device's subsystem, @suspend() or @suspend_late() may be allowed to
* put the device into the low-power state and configure it to generate
* wakeup signals, in which case it generally is not necessary to define
* @suspend_noirq().
*
* @resume_noirq: Prepare for the execution of @resume() by carrying out any
* operations required for resuming the device that might be racing with
* its driver's interrupt handler, which is guaranteed not to run while
* @resume_noirq() is being executed.
*
* @freeze_noirq: Complete the actions started by @freeze(). Carry out any
* additional operations required for freezing the device that might be
* racing with its driver's interrupt handler, which is guaranteed not to
* run while @freeze_noirq() is being executed.
* The power state of the device should not be changed by either @freeze(),
* or @freeze_late(), or @freeze_noirq() and it should not be configured to
* signal system wakeup by any of these callbacks.
*
* @thaw_noirq: Prepare for the execution of @thaw() by carrying out any
* operations required for thawing the device that might be racing with its
* driver's interrupt handler, which is guaranteed not to run while
* @thaw_noirq() is being executed.
*
* @poweroff_noirq: Complete the actions started by @poweroff(). Analogous to
* @suspend_noirq(), but it need not save the device's settings in memory.
*
* @restore_noirq: Prepare for the execution of @restore() by carrying out any
* operations required for thawing the device that might be racing with its
* driver's interrupt handler, which is guaranteed not to run while
* @restore_noirq() is being executed. Analogous to @resume_noirq().
*
* All of the above callbacks, except for @complete(), return error codes.
* However, the error codes returned by the resume operations, @resume(),
* @thaw(), @restore(), @resume_noirq(), @thaw_noirq(), and @restore_noirq(), do
* not cause the PM core to abort the resume transition during which they are
* returned. The error codes returned in those cases are only printed by the PM
* core to the system logs for debugging purposes. Still, it is recommended
* that drivers only return error codes from their resume methods in case of an
* unrecoverable failure (i.e. when the device being handled refuses to resume
* and becomes unusable) to allow us to modify the PM core in the future, so
* that it can avoid attempting to handle devices that failed to resume and
* their children.
*
* It is allowed to unregister devices while the above callbacks are being
* executed. However, a callback routine must NOT try to unregister the device
* it was called for, although it may unregister children of that device (for
* example, if it detects that a child was unplugged while the system was
* asleep).
*
* Refer to Documentation/power/devices.txt for more information about the role
* of the above callbacks in the system suspend process.
*
* There also are callbacks related to runtime power management of devices.
* Again, these callbacks are executed by the PM core only for subsystems
* (PM domains, device types, classes and bus types) and the subsystem-level
* callbacks are supposed to invoke the driver callbacks. Moreover, the exact
* actions to be performed by a device driver's callbacks generally depend on
* the platform and subsystem the device belongs to.
*
* @runtime_suspend: Prepare the device for a condition in which it won't be
* able to communicate with the CPU(s) and RAM due to power management.
* This need not mean that the device should be put into a low-power state.
* For example, if the device is behind a link which is about to be turned
* off, the device may remain at full power. If the device does go to low
* power and is capable of generating runtime wakeup events, remote wakeup
* (i.e., a hardware mechanism allowing the device to request a change of
* its power state via an interrupt) should be enabled for it.
*
* @runtime_resume: Put the device into the fully active state in response to a
* wakeup event generated by hardware or at the request of software. If
* necessary, put the device into the full-power state and restore its
* registers, so that it is fully operational.
*
* @runtime_idle: Device appears to be inactive and it might be put into a
* low-power state if all of the necessary conditions are satisfied.
* Check these conditions, and return 0 if it's appropriate to let the PM
* core queue a suspend request for the device.
*
* Refer to Documentation/power/runtime_pm.txt for more information about the
* role of the above callbacks in device runtime power management.
*
*/
struct dev_pm_ops {
int (*prepare)(struct device *dev);
void (*complete)(struct device *dev);
int (*suspend)(struct device *dev);
int (*resume)(struct device *dev);
int (*freeze)(struct device *dev);
int (*thaw)(struct device *dev);
int (*poweroff)(struct device *dev);
int (*restore)(struct device *dev);
int (*suspend_late)(struct device *dev);
int (*resume_early)(struct device *dev);
int (*freeze_late)(struct device *dev);
int (*thaw_early)(struct device *dev);
int (*poweroff_late)(struct device *dev);
int (*restore_early)(struct device *dev);
int (*suspend_noirq)(struct device *dev);
int (*resume_noirq)(struct device *dev);
int (*freeze_noirq)(struct device *dev);
int (*thaw_noirq)(struct device *dev);
int (*poweroff_noirq)(struct device *dev);
int (*restore_noirq)(struct device *dev);
int (*runtime_suspend)(struct device *dev);
int (*runtime_resume)(struct device *dev);
int (*runtime_idle)(struct device *dev);
};
#ifdef CONFIG_PM_SLEEP
#define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
.suspend = suspend_fn, \
.resume = resume_fn, \
.freeze = suspend_fn, \
.thaw = resume_fn, \
.poweroff = suspend_fn, \
.restore = resume_fn,
#else
#define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
#endif
#ifdef CONFIG_PM_SLEEP
#define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
.suspend_late = suspend_fn, \
.resume_early = resume_fn, \
.freeze_late = suspend_fn, \
.thaw_early = resume_fn, \
.poweroff_late = suspend_fn, \
.restore_early = resume_fn,
#else
#define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
#endif
#ifdef CONFIG_PM_RUNTIME
#define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
.runtime_suspend = suspend_fn, \
.runtime_resume = resume_fn, \
.runtime_idle = idle_fn,
#else
#define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
#endif
#ifdef CONFIG_PM
#define SET_PM_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
.runtime_suspend = suspend_fn, \
.runtime_resume = resume_fn, \
.runtime_idle = idle_fn,
#else
#define SET_PM_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
#endif
/*
* Use this if you want to use the same suspend and resume callbacks for suspend
* to RAM and hibernation.
*/
#define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
const struct dev_pm_ops name = { \
SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
}
/*
* Use this for defining a set of PM operations to be used in all situations
* (system suspend, hibernation or runtime PM).
* NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
* be different from the corresponding runtime PM callbacks, .runtime_suspend(),
* and .runtime_resume(), because .runtime_suspend() always works on an already
* quiescent device, while .suspend() should assume that the device may be doing
* something when it is called (it should ensure that the device will be
* quiescent after it has returned). Therefore it's better to point the "late"
* suspend and "early" resume callback pointers, .suspend_late() and
* .resume_early(), to the same routines as .runtime_suspend() and
* .runtime_resume(), respectively (and analogously for hibernation).
*/
#define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
const struct dev_pm_ops name = { \
SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
}
/**
* PM_EVENT_ messages
*
* The following PM_EVENT_ messages are defined for the internal use of the PM
* core, in order to provide a mechanism allowing the high level suspend and
* hibernation code to convey the necessary information to the device PM core
* code:
*
* ON No transition.
*
* FREEZE System is going to hibernate, call ->prepare() and ->freeze()
* for all devices.
*
* SUSPEND System is going to suspend, call ->prepare() and ->suspend()
* for all devices.
*
* HIBERNATE Hibernation image has been saved, call ->prepare() and
* ->poweroff() for all devices.
*
* QUIESCE Contents of main memory are going to be restored from a (loaded)
* hibernation image, call ->prepare() and ->freeze() for all
* devices.
*
* RESUME System is resuming, call ->resume() and ->complete() for all
* devices.
*
* THAW Hibernation image has been created, call ->thaw() and
* ->complete() for all devices.
*
* RESTORE Contents of main memory have been restored from a hibernation
* image, call ->restore() and ->complete() for all devices.
*
* RECOVER Creation of a hibernation image or restoration of the main
* memory contents from a hibernation image has failed, call
* ->thaw() and ->complete() for all devices.
*
* The following PM_EVENT_ messages are defined for internal use by
* kernel subsystems. They are never issued by the PM core.
*
* USER_SUSPEND Manual selective suspend was issued by userspace.
*
* USER_RESUME Manual selective resume was issued by userspace.
*
* REMOTE_WAKEUP Remote-wakeup request was received from the device.
*
* AUTO_SUSPEND Automatic (device idle) runtime suspend was
* initiated by the subsystem.
*
* AUTO_RESUME Automatic (device needed) runtime resume was
* requested by a driver.
*/
#define PM_EVENT_INVALID (-1)
#define PM_EVENT_ON 0x0000
#define PM_EVENT_FREEZE 0x0001
#define PM_EVENT_SUSPEND 0x0002
#define PM_EVENT_HIBERNATE 0x0004
#define PM_EVENT_QUIESCE 0x0008
#define PM_EVENT_RESUME 0x0010
#define PM_EVENT_THAW 0x0020
#define PM_EVENT_RESTORE 0x0040
#define PM_EVENT_RECOVER 0x0080
#define PM_EVENT_USER 0x0100
#define PM_EVENT_REMOTE 0x0200
#define PM_EVENT_AUTO 0x0400
#define PM_EVENT_SLEEP (PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
#define PM_EVENT_USER_SUSPEND (PM_EVENT_USER | PM_EVENT_SUSPEND)
#define PM_EVENT_USER_RESUME (PM_EVENT_USER | PM_EVENT_RESUME)
#define PM_EVENT_REMOTE_RESUME (PM_EVENT_REMOTE | PM_EVENT_RESUME)
#define PM_EVENT_AUTO_SUSPEND (PM_EVENT_AUTO | PM_EVENT_SUSPEND)
#define PM_EVENT_AUTO_RESUME (PM_EVENT_AUTO | PM_EVENT_RESUME)
#define PMSG_INVALID ((struct pm_message){ .event = PM_EVENT_INVALID, })
#define PMSG_ON ((struct pm_message){ .event = PM_EVENT_ON, })
#define PMSG_FREEZE ((struct pm_message){ .event = PM_EVENT_FREEZE, })
#define PMSG_QUIESCE ((struct pm_message){ .event = PM_EVENT_QUIESCE, })
#define PMSG_SUSPEND ((struct pm_message){ .event = PM_EVENT_SUSPEND, })
#define PMSG_HIBERNATE ((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
#define PMSG_RESUME ((struct pm_message){ .event = PM_EVENT_RESUME, })
#define PMSG_THAW ((struct pm_message){ .event = PM_EVENT_THAW, })
#define PMSG_RESTORE ((struct pm_message){ .event = PM_EVENT_RESTORE, })
#define PMSG_RECOVER ((struct pm_message){ .event = PM_EVENT_RECOVER, })
#define PMSG_USER_SUSPEND ((struct pm_message) \
{ .event = PM_EVENT_USER_SUSPEND, })
#define PMSG_USER_RESUME ((struct pm_message) \
{ .event = PM_EVENT_USER_RESUME, })
#define PMSG_REMOTE_RESUME ((struct pm_message) \
{ .event = PM_EVENT_REMOTE_RESUME, })
#define PMSG_AUTO_SUSPEND ((struct pm_message) \
{ .event = PM_EVENT_AUTO_SUSPEND, })
#define PMSG_AUTO_RESUME ((struct pm_message) \
{ .event = PM_EVENT_AUTO_RESUME, })
#define PMSG_IS_AUTO(msg) (((msg).event & PM_EVENT_AUTO) != 0)
/**
* Device run-time power management status.
*
* These status labels are used internally by the PM core to indicate the
* current status of a device with respect to the PM core operations. They do
* not reflect the actual power state of the device or its status as seen by the
* driver.
*
* RPM_ACTIVE Device is fully operational. Indicates that the device
* bus type's ->runtime_resume() callback has completed
* successfully.
*
* RPM_SUSPENDED Device bus type's ->runtime_suspend() callback has
* completed successfully. The device is regarded as
* suspended.
*
* RPM_RESUMING Device bus type's ->runtime_resume() callback is being
* executed.
*
* RPM_SUSPENDING Device bus type's ->runtime_suspend() callback is being
* executed.
*/
enum rpm_status {
RPM_ACTIVE = 0,
RPM_RESUMING,
RPM_SUSPENDED,
RPM_SUSPENDING,
};
/**
* Device run-time power management request types.
*
* RPM_REQ_NONE Do nothing.
*
* RPM_REQ_IDLE Run the device bus type's ->runtime_idle() callback
*
* RPM_REQ_SUSPEND Run the device bus type's ->runtime_suspend() callback
*
* RPM_REQ_AUTOSUSPEND Same as RPM_REQ_SUSPEND, but not until the device has
* been inactive for as long as power.autosuspend_delay
*
* RPM_REQ_RESUME Run the device bus type's ->runtime_resume() callback
*/
enum rpm_request {
RPM_REQ_NONE = 0,
RPM_REQ_IDLE,
RPM_REQ_SUSPEND,
RPM_REQ_AUTOSUSPEND,
RPM_REQ_RESUME,
};
struct wakeup_source;
struct pm_domain_data {
struct list_head list_node;
struct device *dev;
};
struct pm_subsys_data {
spinlock_t lock;
unsigned int refcount;
#ifdef CONFIG_PM_CLK
struct list_head clock_list;
#endif
#ifdef CONFIG_PM_GENERIC_DOMAINS
struct pm_domain_data *domain_data;
#endif
};
struct dev_pm_info {
pm_message_t power_state;
unsigned int can_wakeup:1;
unsigned int async_suspend:1;
bool is_prepared:1; /* Owned by the PM core */
bool is_suspended:1; /* Ditto */
bool is_noirq_suspended:1;
bool is_late_suspended:1;
bool ignore_children:1;
bool early_init:1; /* Owned by the PM core */
spinlock_t lock;
#ifdef CONFIG_PM_SLEEP
struct list_head entry;
struct completion completion;
struct wakeup_source *wakeup;
bool wakeup_path:1;
bool syscore:1;
#else
unsigned int should_wakeup:1;
#endif
#ifdef CONFIG_PM_RUNTIME
struct timer_list suspend_timer;
unsigned long timer_expires;
struct work_struct work;
wait_queue_head_t wait_queue;
atomic_t usage_count;
atomic_t child_count;
unsigned int disable_depth:3;
unsigned int idle_notification:1;
unsigned int request_pending:1;
unsigned int deferred_resume:1;
unsigned int run_wake:1;
unsigned int runtime_auto:1;
unsigned int no_callbacks:1;
unsigned int irq_safe:1;
unsigned int use_autosuspend:1;
unsigned int timer_autosuspends:1;
unsigned int memalloc_noio:1;
enum rpm_request request;
enum rpm_status runtime_status;
int runtime_error;
int autosuspend_delay;
unsigned long last_busy;
unsigned long active_jiffies;
unsigned long suspended_jiffies;
unsigned long accounting_timestamp;
#endif
struct pm_subsys_data *subsys_data; /* Owned by the subsystem. */
void (*set_latency_tolerance)(struct device *, s32);
struct dev_pm_qos *qos;
};
extern void update_pm_runtime_accounting(struct device *dev);
extern int dev_pm_get_subsys_data(struct device *dev);
extern int dev_pm_put_subsys_data(struct device *dev);
/*
* Power domains provide callbacks that are executed during system suspend,
* hibernation, system resume and during runtime PM transitions along with
* subsystem-level and driver-level callbacks.
*/
struct dev_pm_domain {
struct dev_pm_ops ops;
};
/*
* The PM_EVENT_ messages are also used by drivers implementing the legacy
* suspend framework, based on the ->suspend() and ->resume() callbacks common
* for suspend and hibernation transitions, according to the rules below.
*/
/* Necessary, because several drivers use PM_EVENT_PRETHAW */
#define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
/*
* 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.
*
* HIBERNATE Enter a low power device state appropriate for the hibernation
* state (eg. ACPI S4) 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.
*/
#ifdef CONFIG_PM_SLEEP
extern void device_pm_lock(void);
extern void dpm_resume_start(pm_message_t state);
extern void dpm_resume_end(pm_message_t state);
extern void dpm_resume(pm_message_t state);
extern void dpm_complete(pm_message_t state);
extern void device_pm_unlock(void);
extern int dpm_suspend_end(pm_message_t state);
extern int dpm_suspend_start(pm_message_t state);
extern int dpm_suspend(pm_message_t state);
extern int dpm_prepare(pm_message_t state);
extern void __suspend_report_result(const char *function, void *fn, int ret);
#define suspend_report_result(fn, ret) \
do { \
__suspend_report_result(__func__, fn, ret); \
} while (0)
extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
extern void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *));
extern int pm_generic_prepare(struct device *dev);
extern int pm_generic_suspend_late(struct device *dev);
extern int pm_generic_suspend_noirq(struct device *dev);
extern int pm_generic_suspend(struct device *dev);
extern int pm_generic_resume_early(struct device *dev);
extern int pm_generic_resume_noirq(struct device *dev);
extern int pm_generic_resume(struct device *dev);
extern int pm_generic_freeze_noirq(struct device *dev);
extern int pm_generic_freeze_late(struct device *dev);
extern int pm_generic_freeze(struct device *dev);
extern int pm_generic_thaw_noirq(struct device *dev);
extern int pm_generic_thaw_early(struct device *dev);
extern int pm_generic_thaw(struct device *dev);
extern int pm_generic_restore_noirq(struct device *dev);
extern int pm_generic_restore_early(struct device *dev);
extern int pm_generic_restore(struct device *dev);
extern int pm_generic_poweroff_noirq(struct device *dev);
extern int pm_generic_poweroff_late(struct device *dev);
extern int pm_generic_poweroff(struct device *dev);
extern void pm_generic_complete(struct device *dev);
#else /* !CONFIG_PM_SLEEP */
#define device_pm_lock() do {} while (0)
#define device_pm_unlock() do {} while (0)
static inline int dpm_suspend_start(pm_message_t state)
{
return 0;
}
#define suspend_report_result(fn, ret) do {} while (0)
static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
{
return 0;
}
static inline void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
{
}
#define pm_generic_prepare NULL
#define pm_generic_suspend_late NULL
#define pm_generic_suspend_noirq NULL
#define pm_generic_suspend NULL
#define pm_generic_resume_early NULL
#define pm_generic_resume_noirq NULL
#define pm_generic_resume NULL
#define pm_generic_freeze_noirq NULL
#define pm_generic_freeze_late NULL
#define pm_generic_freeze NULL
#define pm_generic_thaw_noirq NULL
#define pm_generic_thaw_early NULL
#define pm_generic_thaw NULL
#define pm_generic_restore_noirq NULL
#define pm_generic_restore_early NULL
#define pm_generic_restore NULL
#define pm_generic_poweroff_noirq NULL
#define pm_generic_poweroff_late NULL
#define pm_generic_poweroff NULL
#define pm_generic_complete NULL
#endif /* !CONFIG_PM_SLEEP */
/* How to reorder dpm_list after device_move() */
enum dpm_order {
DPM_ORDER_NONE,
DPM_ORDER_DEV_AFTER_PARENT,
DPM_ORDER_PARENT_BEFORE_DEV,
DPM_ORDER_DEV_LAST,
};
#endif /* _LINUX_PM_H */