Merge branch 'pm-sleep' (643161ac) · Commits · 戴 / test

Documentation/power/devices.txt

+61 −32

Original line number	Diff line number	Diff line
		@@ -96,6 +96,12 @@ struct dev_pm_ops {
		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);
		@@ -305,7 +311,7 @@ Entering System Suspend
		-----------------------
		When the system goes into the standby or memory sleep state, the phases are:

		prepare, suspend, suspend_noirq.
		prepare, suspend, suspend_late, suspend_noirq.

		1. The prepare phase is meant to prevent races by preventing new devices
		from being registered; the PM core would never know that all the
		@@ -324,7 +330,12 @@ When the system goes into the standby or memory sleep state, the phases are:
		appropriate low-power state, depending on the bus type the device is on,
		and they may enable wakeup events.

		3. The suspend_noirq phase occurs after IRQ handlers have been disabled,
		3 For a number of devices it is convenient to split suspend into the
		"quiesce device" and "save device state" phases, in which cases
		suspend_late is meant to do the latter. It is always executed after
		runtime power management has been disabled for all devices.

		4. The suspend_noirq phase occurs after IRQ handlers have been disabled,
		which means that the driver's interrupt handler will not be called while
		the callback method is running. The methods should save the values of
		the device's registers that weren't saved previously and finally put the
		@@ -359,7 +370,7 @@ Leaving System Suspend
		----------------------
		When resuming from standby or memory sleep, the phases are:

		resume_noirq, resume, complete.
		resume_noirq, resume_early, resume, complete.

		1. The resume_noirq callback methods should perform any actions needed
		before the driver's interrupt handlers are invoked. This generally
		@@ -375,14 +386,18 @@ When resuming from standby or memory sleep, the phases are:
		device driver's ->pm.resume_noirq() method to perform device-specific
		actions.

		2. The resume methods should bring the the device back to its operating
		2. The resume_early methods should prepare devices for the execution of
		the resume methods. This generally involves undoing the actions of the
		preceding suspend_late phase.

		3 The resume methods should bring the the device back to its operating
		state, so that it can perform normal I/O. This generally involves
		undoing the actions of the suspend phase.

		3. The complete phase uses only a bus callback. The method should undo the
		actions of the prepare phase. Note, however, that new children may be
		registered below the device as soon as the resume callbacks occur; it's
		not necessary to wait until the complete phase.
		4. The complete phase should undo the actions of the prepare phase. Note,
		however, that new children may be registered below the device as soon as
		the resume callbacks occur; it's not necessary to wait until the
		complete phase.

		At the end of these phases, drivers should be as functional as they were before
		suspending: I/O can be performed using DMA and IRQs, and the relevant clocks are
		@@ -429,8 +444,8 @@ an image of the system memory while everything is stable, reactivate all
		devices (thaw), write the image to permanent storage, and finally shut down the
		system (poweroff). The phases used to accomplish this are:

		prepare, freeze, freeze_noirq, thaw_noirq, thaw, complete,
		prepare, poweroff, poweroff_noirq
		prepare, freeze, freeze_late, freeze_noirq, thaw_noirq, thaw_early,
		thaw, complete, prepare, poweroff, poweroff_late, poweroff_noirq

		1. The prepare phase is discussed in the "Entering System Suspend" section
		above.
		@@ -441,7 +456,11 @@ system (poweroff). The phases used to accomplish this are:
		save time it's best not to do so. Also, the device should not be
		prepared to generate wakeup events.

		3. The freeze_noirq phase is analogous to the suspend_noirq phase discussed
		3. The freeze_late phase is analogous to the suspend_late phase described
		above, except that the device should not be put in a low-power state and
		should not be allowed to generate wakeup events by it.

		4. The freeze_noirq phase is analogous to the suspend_noirq phase discussed
		above, except again that the device should not be put in a low-power
		state and should not be allowed to generate wakeup events.

		@@ -449,15 +468,19 @@ At this point the system image is created. All devices should be inactive and
		the contents of memory should remain undisturbed while this happens, so that the
		image forms an atomic snapshot of the system state.

		4. The thaw_noirq phase is analogous to the resume_noirq phase discussed
		5. The thaw_noirq phase is analogous to the resume_noirq phase discussed
		above. The main difference is that its methods can assume the device is
		in the same state as at the end of the freeze_noirq phase.

		5. The thaw phase is analogous to the resume phase discussed above. Its
		6. The thaw_early phase is analogous to the resume_early phase described
		above. Its methods should undo the actions of the preceding
		freeze_late, if necessary.

		7. The thaw phase is analogous to the resume phase discussed above. Its
		methods should bring the device back to an operating state, so that it
		can be used for saving the image if necessary.

		6. The complete phase is discussed in the "Leaving System Suspend" section
		8. The complete phase is discussed in the "Leaving System Suspend" section
		above.

		At this point the system image is saved, and the devices then need to be
		@@ -465,16 +488,19 @@ prepared for the upcoming system shutdown. This is much like suspending them
		before putting the system into the standby or memory sleep state, and the phases
		are similar.

		7. The prepare phase is discussed above.
		9. The prepare phase is discussed above.

		10. The poweroff phase is analogous to the suspend phase.

		8. The poweroff phase is analogous to the suspend phase.
		11. The poweroff_late phase is analogous to the suspend_late phase.

		9. The poweroff_noirq phase is analogous to the suspend_noirq phase.
		12. The poweroff_noirq phase is analogous to the suspend_noirq phase.

		The poweroff and poweroff_noirq callbacks should do essentially the same things
		as the suspend and suspend_noirq callbacks. The only notable difference is that
		they need not store the device register values, because the registers should
		already have been stored during the freeze or freeze_noirq phases.
		The poweroff, poweroff_late and poweroff_noirq callbacks should do essentially
		the same things as the suspend, suspend_late and suspend_noirq callbacks,
		respectively. The only notable difference is that they need not store the
		device register values, because the registers should already have been stored
		during the freeze, freeze_late or freeze_noirq phases.


		Leaving Hibernation
		@@ -518,22 +544,25 @@ To achieve this, the image kernel must restore the devices' pre-hibernation
		functionality. The operation is much like waking up from the memory sleep
		state, although it involves different phases:

		restore_noirq, restore, complete
		restore_noirq, restore_early, restore, complete

		1. The restore_noirq phase is analogous to the resume_noirq phase.

		2. The restore phase is analogous to the resume phase.
		2. The restore_early phase is analogous to the resume_early phase.

		3. The restore phase is analogous to the resume phase.

		3. The complete phase is discussed above.
		4. The complete phase is discussed above.

		The main difference from resume[_noirq] is that restore[_noirq] must assume the
		device has been accessed and reconfigured by the boot loader or the boot kernel.
		Consequently the state of the device may be different from the state remembered
		from the freeze and freeze_noirq phases. The device may even need to be reset
		and completely re-initialized. In many cases this difference doesn't matter, so
		the resume[_noirq] and restore[_norq] method pointers can be set to the same
		routines. Nevertheless, different callback pointers are used in case there is a
		situation where it actually matters.
		The main difference from resume[_early\|_noirq] is that restore[_early\|_noirq]
		must assume the device has been accessed and reconfigured by the boot loader or
		the boot kernel. Consequently the state of the device may be different from the
		state remembered from the freeze, freeze_late and freeze_noirq phases. The
		device may even need to be reset and completely re-initialized. In many cases
		this difference doesn't matter, so the resume[_early\|_noirq] and
		restore[_early\|_norq] method pointers can be set to the same routines.
		Nevertheless, different callback pointers are used in case there is a situation
		where it actually does matter.


		Device Power Management Domains

Documentation/power/freezing-of-tasks.txt

+21 −0

Original line number	Diff line number	Diff line
		@@ -63,6 +63,27 @@ devices have been reinitialized, the function thaw_processes() is called in
		order to clear the PF_FROZEN flag for each frozen task. Then, the tasks that
		have been frozen leave __refrigerator() and continue running.


		Rationale behind the functions dealing with freezing and thawing of tasks:
		-------------------------------------------------------------------------

		freeze_processes():
		- freezes only userspace tasks

		freeze_kernel_threads():
		- freezes all tasks (including kernel threads) because we can't freeze
		kernel threads without freezing userspace tasks

		thaw_kernel_threads():
		- thaws only kernel threads; this is particularly useful if we need to do
		anything special in between thawing of kernel threads and thawing of
		userspace tasks, or if we want to postpone the thawing of userspace tasks

		thaw_processes():
		- thaws all tasks (including kernel threads) because we can't thaw userspace
		tasks without thawing kernel threads


		III. Which kernel threads are freezable?

		Kernel threads are not freezable by default. However, a kernel thread may clear

arch/x86/kernel/apm_32.c

+5 −6

Original line number	Diff line number	Diff line
		@@ -1234,8 +1234,7 @@ static int suspend(int vetoable)
		struct apm_user *as;

		dpm_suspend_start(PMSG_SUSPEND);

		dpm_suspend_noirq(PMSG_SUSPEND);
		dpm_suspend_end(PMSG_SUSPEND);

		local_irq_disable();
		syscore_suspend();
		@@ -1259,9 +1258,9 @@ static int suspend(int vetoable)
		syscore_resume();
		local_irq_enable();

		dpm_resume_noirq(PMSG_RESUME);

		dpm_resume_start(PMSG_RESUME);
		dpm_resume_end(PMSG_RESUME);

		queue_event(APM_NORMAL_RESUME, NULL);
		spin_lock(&user_list_lock);
		for (as = user_list; as != NULL; as = as->next) {
		@@ -1277,7 +1276,7 @@ static void standby(void)
		{
		int err;

		dpm_suspend_noirq(PMSG_SUSPEND);
		dpm_suspend_end(PMSG_SUSPEND);

		local_irq_disable();
		syscore_suspend();
		@@ -1291,7 +1290,7 @@ static void standby(void)
		syscore_resume();
		local_irq_enable();

		dpm_resume_noirq(PMSG_RESUME);
		dpm_resume_start(PMSG_RESUME);
		}

		static apm_event_t get_event(void)

drivers/base/power/generic_ops.c

+104 −53

Original line number	Diff line number	Diff line
		@@ -92,59 +92,28 @@ int pm_generic_prepare(struct device *dev)
		}

		/**
		* __pm_generic_call - Generic suspend/freeze/poweroff/thaw subsystem callback.
		* @dev: Device to handle.
		* @event: PM transition of the system under way.
		* @bool: Whether or not this is the "noirq" stage.
		*
		* Execute the PM callback corresponding to @event provided by the driver of
		* @dev, if defined, and return its error code. Return 0 if the callback is
		* not present.
		* pm_generic_suspend_noirq - Generic suspend_noirq callback for subsystems.
		* @dev: Device to suspend.
		*/
		static int __pm_generic_call(struct device *dev, int event, bool noirq)
		int pm_generic_suspend_noirq(struct device *dev)
		{
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
		int (callback)(struct device );

		if (!pm)
		return 0;

		switch (event) {
		case PM_EVENT_SUSPEND:
		callback = noirq ? pm->suspend_noirq : pm->suspend;
		break;
		case PM_EVENT_FREEZE:
		callback = noirq ? pm->freeze_noirq : pm->freeze;
		break;
		case PM_EVENT_HIBERNATE:
		callback = noirq ? pm->poweroff_noirq : pm->poweroff;
		break;
		case PM_EVENT_RESUME:
		callback = noirq ? pm->resume_noirq : pm->resume;
		break;
		case PM_EVENT_THAW:
		callback = noirq ? pm->thaw_noirq : pm->thaw;
		break;
		case PM_EVENT_RESTORE:
		callback = noirq ? pm->restore_noirq : pm->restore;
		break;
		default:
		callback = NULL;
		break;
		}

		return callback ? callback(dev) : 0;
		return pm && pm->suspend_noirq ? pm->suspend_noirq(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_suspend_noirq);

		/**
		* pm_generic_suspend_noirq - Generic suspend_noirq callback for subsystems.
		* pm_generic_suspend_late - Generic suspend_late callback for subsystems.
		* @dev: Device to suspend.
		*/
		int pm_generic_suspend_noirq(struct device *dev)
		int pm_generic_suspend_late(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_SUSPEND, true);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->suspend_late ? pm->suspend_late(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_suspend_noirq);
		EXPORT_SYMBOL_GPL(pm_generic_suspend_late);

		/**
		* pm_generic_suspend - Generic suspend callback for subsystems.
		@@ -152,7 +121,9 @@ EXPORT_SYMBOL_GPL(pm_generic_suspend_noirq);
		*/
		int pm_generic_suspend(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_SUSPEND, false);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->suspend ? pm->suspend(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_suspend);

		@@ -162,17 +133,33 @@ EXPORT_SYMBOL_GPL(pm_generic_suspend);
		*/
		int pm_generic_freeze_noirq(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_FREEZE, true);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->freeze_noirq ? pm->freeze_noirq(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_freeze_noirq);

		/**
		* pm_generic_freeze_late - Generic freeze_late callback for subsystems.
		* @dev: Device to freeze.
		*/
		int pm_generic_freeze_late(struct device *dev)
		{
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->freeze_late ? pm->freeze_late(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_freeze_late);

		/**
		* pm_generic_freeze - Generic freeze callback for subsystems.
		* @dev: Device to freeze.
		*/
		int pm_generic_freeze(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_FREEZE, false);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->freeze ? pm->freeze(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_freeze);

		@@ -182,17 +169,33 @@ EXPORT_SYMBOL_GPL(pm_generic_freeze);
		*/
		int pm_generic_poweroff_noirq(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_HIBERNATE, true);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->poweroff_noirq ? pm->poweroff_noirq(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_poweroff_noirq);

		/**
		* pm_generic_poweroff_late - Generic poweroff_late callback for subsystems.
		* @dev: Device to handle.
		*/
		int pm_generic_poweroff_late(struct device *dev)
		{
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->poweroff_late ? pm->poweroff_late(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_poweroff_late);

		/**
		* pm_generic_poweroff - Generic poweroff callback for subsystems.
		* @dev: Device to handle.
		*/
		int pm_generic_poweroff(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_HIBERNATE, false);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->poweroff ? pm->poweroff(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_poweroff);

		@@ -202,17 +205,33 @@ EXPORT_SYMBOL_GPL(pm_generic_poweroff);
		*/
		int pm_generic_thaw_noirq(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_THAW, true);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->thaw_noirq ? pm->thaw_noirq(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_thaw_noirq);

		/**
		* pm_generic_thaw_early - Generic thaw_early callback for subsystems.
		* @dev: Device to thaw.
		*/
		int pm_generic_thaw_early(struct device *dev)
		{
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->thaw_early ? pm->thaw_early(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_thaw_early);

		/**
		* pm_generic_thaw - Generic thaw callback for subsystems.
		* @dev: Device to thaw.
		*/
		int pm_generic_thaw(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_THAW, false);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->thaw ? pm->thaw(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_thaw);

		@@ -222,17 +241,33 @@ EXPORT_SYMBOL_GPL(pm_generic_thaw);
		*/
		int pm_generic_resume_noirq(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_RESUME, true);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->resume_noirq ? pm->resume_noirq(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_resume_noirq);

		/**
		* pm_generic_resume_early - Generic resume_early callback for subsystems.
		* @dev: Device to resume.
		*/
		int pm_generic_resume_early(struct device *dev)
		{
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->resume_early ? pm->resume_early(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_resume_early);

		/**
		* pm_generic_resume - Generic resume callback for subsystems.
		* @dev: Device to resume.
		*/
		int pm_generic_resume(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_RESUME, false);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->resume ? pm->resume(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_resume);

		@@ -242,17 +277,33 @@ EXPORT_SYMBOL_GPL(pm_generic_resume);
		*/
		int pm_generic_restore_noirq(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_RESTORE, true);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->restore_noirq ? pm->restore_noirq(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_restore_noirq);

		/**
		* pm_generic_restore_early - Generic restore_early callback for subsystems.
		* @dev: Device to resume.
		*/
		int pm_generic_restore_early(struct device *dev)
		{
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->restore_early ? pm->restore_early(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_restore_early);

		/**
		* pm_generic_restore - Generic restore callback for subsystems.
		* @dev: Device to restore.
		*/
		int pm_generic_restore(struct device *dev)
		{
		return __pm_generic_call(dev, PM_EVENT_RESTORE, false);
		const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

		return pm && pm->restore ? pm->restore(dev) : 0;
		}
		EXPORT_SYMBOL_GPL(pm_generic_restore);

drivers/base/power/main.c

+225 −22

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