/* * 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 #include #include #include #include #include /* * 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(). If the transition is a suspend to memory or standby (that * is, not related to hibernation), the return value of @prepare() may be * used to indicate to the PM core to leave the device in runtime suspend * if applicable. Namely, if @prepare() returns a positive number, the PM * core will understand that as a declaration that the device appears to be * runtime-suspended and it may be left in that state during the entire * transition and during the subsequent resume if all of its descendants * are left in runtime suspend too. If that happens, @complete() will be * executed directly after @prepare() and it must ensure the proper * functioning of the device after the system resume. * 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. If the corresponding * @prepare() at the beginning of the suspend transition returned a * positive number and the device was left in runtime suspend (without * executing any suspend and resume callbacks for it), @complete() will be * the only callback executed for the device during resume. In that case, * @complete() must be prepared to do whatever is necessary to ensure the * proper functioning of the device after the system resume. To this end, * @complete() can check the power.direct_complete flag of the device to * learn whether (unset) or not (set) the previous suspend and resume * callbacks have been executed for it. * * @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 */ bool direct_complete: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; void (*detach)(struct device *dev, bool power_off); }; /* * 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 */