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Diffstat (limited to 'include/linux/pm.h')
| -rw-r--r-- | include/linux/pm.h | 599 |
1 files changed, 599 insertions, 0 deletions
diff --git a/include/linux/pm.h b/include/linux/pm.h new file mode 100644 index 00000000..411e4f4b --- /dev/null +++ b/include/linux/pm.h @@ -0,0 +1,599 @@ +/* + * 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_idle)(void); +extern void (*pm_power_off)(void); +extern void (*pm_power_off_prepare)(void); + +/* + * 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 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). + * + * The externally visible transitions are handled with the help of the following + * callbacks included in this structure: + * + * @prepare: Prepare the device for the upcoming transition, but do NOT change + * its hardware state. Prevent new children of the device from being + * registered after @prepare() returns (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 the 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 @prepare() for all devices before starting to + * execute suspend callbacks for any of them, so drivers may assume all of + * the other devices to be present and functional while @prepare() is being + * executed. In particular, it is safe to make GFP_KERNEL memory + * allocations from within @prepare(). However, drivers may NOT assume + * anything about the availability of the user space at that time and it + * is not correct to request firmware from within @prepare() (it's too + * late to do that). [To work around this limitation, drivers may + * register suspend and hibernation notifiers that are 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(), + * @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 @complete() after it has executed the appropriate + * resume callback for all devices. + * + * @suspend: Executed before putting the system into a sleep state in which the + * contents of main memory are preserved. Quiesce the device, put it into + * a low power state appropriate for the upcoming system state (such as + * PCI_D3hot), and enable wakeup events as appropriate. + * + * @resume: Executed after waking the system up from a sleep state in which the + * contents of main memory were preserved. Put the device into the + * appropriate state, according to the information saved in memory by the + * preceding @suspend(). The 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 may rely on while resuming. On most + * platforms, there are no restrictions on availability of resources like + * clocks during @resume(). + * + * @freeze: Hibernation-specific, executed before creating a hibernation image. + * Quiesce operations so that a consistent image can be created, but do NOT + * otherwise put the device into a low power device state and do NOT emit + * system wakeup events. Save in main memory the device settings to be + * used by @restore() during the subsequent resume from hibernation or by + * the subsequent @thaw(), if the creation of the image or the restoration + * of main memory contents from it fails. + * + * @thaw: Hibernation-specific, executed after creating a hibernation image OR + * if the creation of the image fails. 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(). + * + * @poweroff: Hibernation-specific, executed after saving a hibernation image. + * Quiesce the device, put it into a low power state appropriate for the + * upcoming system state (such as PCI_D3hot), and enable wakeup events as + * appropriate. + * + * @restore: Hibernation-specific, executed after restoring the contents of main + * memory from a hibernation image. Driver starts working again, + * responding to hardware events and software requests. Drivers may NOT + * make ANY assumptions about the hardware state right prior to @restore(). + * On most platforms, there are no restrictions on availability of + * resources like clocks during @restore(). + * + * @suspend_noirq: Complete the operations of ->suspend() by carrying out any + * actions required for suspending the device that need interrupts to be + * disabled + * + * @resume_noirq: Prepare for the execution of ->resume() by carrying out any + * actions required for resuming the device that need interrupts to be + * disabled + * + * @freeze_noirq: Complete the operations of ->freeze() by carrying out any + * actions required for freezing the device that need interrupts to be + * disabled + * + * @thaw_noirq: Prepare for the execution of ->thaw() by carrying out any + * actions required for thawing the device that need interrupts to be + * disabled + * + * @poweroff_noirq: Complete the operations of ->poweroff() by carrying out any + * actions required for handling the device that need interrupts to be + * disabled + * + * @restore_noirq: Prepare for the execution of ->restore() by carrying out any + * actions required for restoring the operations of the device that need + * interrupts to be disabled + * + * 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 that 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, it is not allowed to unregister a device from within any + * of its own callbacks. + * + * There also are the following callbacks related to run-time power management + * of devices: + * + * @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 run-time wake-up events, remote + * wake-up (i.e., a hardware mechanism allowing the device to request a + * change of its power state via a wake-up event, such as PCI PME) should + * be enabled for it. + * + * @runtime_resume: Put the device into the fully active state in response to a + * wake-up 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 handle the device as appropriate, possibly queueing + * a suspend request for it. The return value is ignored by the PM core. + */ + +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_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_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 + +/* + * 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 + * (sustem suspend, hibernation or runtime PM). + */ +#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) \ +} + +/* + * Use this for subsystems (bus types, device types, device classes) that don't + * need any special suspend/resume handling in addition to invoking the PM + * callbacks provided by device drivers supporting both the system sleep PM and + * runtime PM, make the pm member point to generic_subsys_pm_ops. + */ +#ifdef CONFIG_PM +extern struct dev_pm_ops generic_subsys_pm_ops; +#define GENERIC_SUBSYS_PM_OPS (&generic_subsys_pm_ops) +#else +#define GENERIC_SUBSYS_PM_OPS NULL +#endif + +/** + * 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_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_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, }) + +/** + * 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 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 */ + spinlock_t lock; +#ifdef CONFIG_PM_SLEEP + struct list_head entry; + struct completion completion; + struct wakeup_source *wakeup; +#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 ignore_children:1; + 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; + 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; + void *subsys_data; /* Owned by the subsystem. */ +#endif +}; + +extern void update_pm_runtime_accounting(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_power_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_noirq(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_noirq(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 int pm_generic_prepare(struct device *dev); +extern int pm_generic_suspend(struct device *dev); +extern int pm_generic_resume(struct device *dev); +extern int pm_generic_freeze(struct device *dev); +extern int pm_generic_thaw(struct device *dev); +extern int pm_generic_restore(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; +} + +#define pm_generic_prepare NULL +#define pm_generic_suspend NULL +#define pm_generic_resume NULL +#define pm_generic_freeze NULL +#define pm_generic_thaw NULL +#define pm_generic_restore 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 */ |