![Rafael J. Wysocki](/assets/img/avatar_default.png)
ACPI PM: Add possibility to change suspend sequence There are some systems out there that don't work correctly with our current suspend/hibernation code ordering. Provide a workaround for these systems allowing them to pass 'acpi_sleep=old_ordering' in the kernel command line so that it will use the pre-ACPI 2.0 ("old") suspend code ordering. Unfortunately, this requires us to add a platform hook to the resuming of devices for recovering the platform in case one of the device drivers' .suspend() routines returns error code. Namely, ACPI 1.0 specifies that _PTS should be called before suspending devices, but _WAK still should be called before resuming them in order to undo the changes made by _PTS. However, if there is an error during suspending devices, they are automatically resumed without returning control to the PM core, so the _WAK has to be called from within device_resume() in that cases. The patch also reorders and refactors the ACPI suspend/hibernation code to avoid duplication as far as reasonably possible. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
797 lines
19 KiB
C
797 lines
19 KiB
C
/*
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* drivers/base/power/main.c - Where the driver meets power management.
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*
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* Copyright (c) 2003 Patrick Mochel
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* Copyright (c) 2003 Open Source Development Lab
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*
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* This file is released under the GPLv2
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*
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*
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* The driver model core calls device_pm_add() when a device is registered.
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* This will intialize the embedded device_pm_info object in the device
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* and add it to the list of power-controlled devices. sysfs entries for
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* controlling device power management will also be added.
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*
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* A separate list is used for keeping track of power info, because the power
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* domain dependencies may differ from the ancestral dependencies that the
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* subsystem list maintains.
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*/
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#include <linux/device.h>
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#include <linux/kallsyms.h>
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#include <linux/mutex.h>
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#include <linux/pm.h>
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#include <linux/resume-trace.h>
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#include <linux/rwsem.h>
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#include "../base.h"
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#include "power.h"
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/*
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* The entries in the dpm_list list are in a depth first order, simply
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* because children are guaranteed to be discovered after parents, and
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* are inserted at the back of the list on discovery.
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*
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* Since device_pm_add() may be called with a device semaphore held,
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* we must never try to acquire a device semaphore while holding
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* dpm_list_mutex.
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*/
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LIST_HEAD(dpm_list);
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static DEFINE_MUTEX(dpm_list_mtx);
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/*
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* Set once the preparation of devices for a PM transition has started, reset
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* before starting to resume devices. Protected by dpm_list_mtx.
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*/
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static bool transition_started;
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/**
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* device_pm_lock - lock the list of active devices used by the PM core
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*/
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void device_pm_lock(void)
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{
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mutex_lock(&dpm_list_mtx);
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}
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/**
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* device_pm_unlock - unlock the list of active devices used by the PM core
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*/
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void device_pm_unlock(void)
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{
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mutex_unlock(&dpm_list_mtx);
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}
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/**
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* device_pm_add - add a device to the list of active devices
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* @dev: Device to be added to the list
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*/
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int device_pm_add(struct device *dev)
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{
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int error;
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pr_debug("PM: Adding info for %s:%s\n",
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dev->bus ? dev->bus->name : "No Bus",
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kobject_name(&dev->kobj));
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mutex_lock(&dpm_list_mtx);
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if (dev->parent) {
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if (dev->parent->power.status >= DPM_SUSPENDING) {
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dev_warn(dev, "parent %s is sleeping, will not add\n",
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dev->parent->bus_id);
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WARN_ON(true);
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}
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} else if (transition_started) {
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/*
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* We refuse to register parentless devices while a PM
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* transition is in progress in order to avoid leaving them
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* unhandled down the road
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*/
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WARN_ON(true);
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}
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error = dpm_sysfs_add(dev);
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if (!error) {
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dev->power.status = DPM_ON;
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list_add_tail(&dev->power.entry, &dpm_list);
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}
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mutex_unlock(&dpm_list_mtx);
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return error;
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}
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/**
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* device_pm_remove - remove a device from the list of active devices
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* @dev: Device to be removed from the list
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*
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* This function also removes the device's PM-related sysfs attributes.
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*/
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void device_pm_remove(struct device *dev)
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{
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pr_debug("PM: Removing info for %s:%s\n",
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dev->bus ? dev->bus->name : "No Bus",
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kobject_name(&dev->kobj));
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mutex_lock(&dpm_list_mtx);
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dpm_sysfs_remove(dev);
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list_del_init(&dev->power.entry);
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mutex_unlock(&dpm_list_mtx);
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}
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/**
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* pm_op - execute the PM operation appropiate for given PM event
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* @dev: Device.
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* @ops: PM operations to choose from.
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* @state: PM transition of the system being carried out.
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*/
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static int pm_op(struct device *dev, struct pm_ops *ops, pm_message_t state)
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{
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int error = 0;
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switch (state.event) {
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#ifdef CONFIG_SUSPEND
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case PM_EVENT_SUSPEND:
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if (ops->suspend) {
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error = ops->suspend(dev);
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suspend_report_result(ops->suspend, error);
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}
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break;
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case PM_EVENT_RESUME:
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if (ops->resume) {
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error = ops->resume(dev);
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suspend_report_result(ops->resume, error);
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}
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break;
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#endif /* CONFIG_SUSPEND */
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#ifdef CONFIG_HIBERNATION
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case PM_EVENT_FREEZE:
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case PM_EVENT_QUIESCE:
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if (ops->freeze) {
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error = ops->freeze(dev);
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suspend_report_result(ops->freeze, error);
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}
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break;
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case PM_EVENT_HIBERNATE:
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if (ops->poweroff) {
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error = ops->poweroff(dev);
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suspend_report_result(ops->poweroff, error);
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}
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break;
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case PM_EVENT_THAW:
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case PM_EVENT_RECOVER:
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if (ops->thaw) {
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error = ops->thaw(dev);
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suspend_report_result(ops->thaw, error);
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}
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break;
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case PM_EVENT_RESTORE:
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if (ops->restore) {
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error = ops->restore(dev);
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suspend_report_result(ops->restore, error);
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}
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break;
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#endif /* CONFIG_HIBERNATION */
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default:
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error = -EINVAL;
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}
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return error;
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}
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/**
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* pm_noirq_op - execute the PM operation appropiate for given PM event
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* @dev: Device.
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* @ops: PM operations to choose from.
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* @state: PM transition of the system being carried out.
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*
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* The operation is executed with interrupts disabled by the only remaining
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* functional CPU in the system.
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*/
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static int pm_noirq_op(struct device *dev, struct pm_ext_ops *ops,
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pm_message_t state)
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{
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int error = 0;
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switch (state.event) {
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#ifdef CONFIG_SUSPEND
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case PM_EVENT_SUSPEND:
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if (ops->suspend_noirq) {
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error = ops->suspend_noirq(dev);
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suspend_report_result(ops->suspend_noirq, error);
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}
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break;
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case PM_EVENT_RESUME:
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if (ops->resume_noirq) {
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error = ops->resume_noirq(dev);
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suspend_report_result(ops->resume_noirq, error);
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}
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break;
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#endif /* CONFIG_SUSPEND */
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#ifdef CONFIG_HIBERNATION
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case PM_EVENT_FREEZE:
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case PM_EVENT_QUIESCE:
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if (ops->freeze_noirq) {
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error = ops->freeze_noirq(dev);
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suspend_report_result(ops->freeze_noirq, error);
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}
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break;
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case PM_EVENT_HIBERNATE:
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if (ops->poweroff_noirq) {
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error = ops->poweroff_noirq(dev);
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suspend_report_result(ops->poweroff_noirq, error);
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}
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break;
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case PM_EVENT_THAW:
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case PM_EVENT_RECOVER:
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if (ops->thaw_noirq) {
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error = ops->thaw_noirq(dev);
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suspend_report_result(ops->thaw_noirq, error);
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}
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break;
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case PM_EVENT_RESTORE:
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if (ops->restore_noirq) {
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error = ops->restore_noirq(dev);
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suspend_report_result(ops->restore_noirq, error);
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}
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break;
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#endif /* CONFIG_HIBERNATION */
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default:
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error = -EINVAL;
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}
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return error;
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}
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static char *pm_verb(int event)
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{
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switch (event) {
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case PM_EVENT_SUSPEND:
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return "suspend";
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case PM_EVENT_RESUME:
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return "resume";
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case PM_EVENT_FREEZE:
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return "freeze";
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case PM_EVENT_QUIESCE:
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return "quiesce";
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case PM_EVENT_HIBERNATE:
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return "hibernate";
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case PM_EVENT_THAW:
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return "thaw";
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case PM_EVENT_RESTORE:
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return "restore";
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case PM_EVENT_RECOVER:
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return "recover";
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default:
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return "(unknown PM event)";
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}
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}
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static void pm_dev_dbg(struct device *dev, pm_message_t state, char *info)
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{
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dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event),
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((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ?
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", may wakeup" : "");
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}
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static void pm_dev_err(struct device *dev, pm_message_t state, char *info,
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int error)
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{
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printk(KERN_ERR "PM: Device %s failed to %s%s: error %d\n",
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kobject_name(&dev->kobj), pm_verb(state.event), info, error);
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}
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/*------------------------- Resume routines -------------------------*/
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/**
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* resume_device_noirq - Power on one device (early resume).
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* @dev: Device.
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* @state: PM transition of the system being carried out.
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*
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* Must be called with interrupts disabled.
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*/
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static int resume_device_noirq(struct device *dev, pm_message_t state)
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{
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int error = 0;
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TRACE_DEVICE(dev);
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TRACE_RESUME(0);
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if (!dev->bus)
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goto End;
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if (dev->bus->pm) {
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pm_dev_dbg(dev, state, "EARLY ");
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error = pm_noirq_op(dev, dev->bus->pm, state);
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} else if (dev->bus->resume_early) {
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pm_dev_dbg(dev, state, "legacy EARLY ");
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error = dev->bus->resume_early(dev);
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}
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End:
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TRACE_RESUME(error);
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return error;
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}
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/**
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* dpm_power_up - Power on all regular (non-sysdev) devices.
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* @state: PM transition of the system being carried out.
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*
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* Execute the appropriate "noirq resume" callback for all devices marked
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* as DPM_OFF_IRQ.
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*
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* Must be called with interrupts disabled and only one CPU running.
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*/
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static void dpm_power_up(pm_message_t state)
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{
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struct device *dev;
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list_for_each_entry(dev, &dpm_list, power.entry)
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if (dev->power.status > DPM_OFF) {
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int error;
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dev->power.status = DPM_OFF;
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error = resume_device_noirq(dev, state);
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if (error)
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pm_dev_err(dev, state, " early", error);
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}
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}
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/**
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* device_power_up - Turn on all devices that need special attention.
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* @state: PM transition of the system being carried out.
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*
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* Power on system devices, then devices that required we shut them down
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* with interrupts disabled.
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*
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* Must be called with interrupts disabled.
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*/
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void device_power_up(pm_message_t state)
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{
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sysdev_resume();
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dpm_power_up(state);
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}
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EXPORT_SYMBOL_GPL(device_power_up);
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/**
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* resume_device - Restore state for one device.
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* @dev: Device.
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* @state: PM transition of the system being carried out.
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*/
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static int resume_device(struct device *dev, pm_message_t state)
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{
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int error = 0;
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TRACE_DEVICE(dev);
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TRACE_RESUME(0);
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down(&dev->sem);
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if (dev->bus) {
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if (dev->bus->pm) {
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pm_dev_dbg(dev, state, "");
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error = pm_op(dev, &dev->bus->pm->base, state);
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} else if (dev->bus->resume) {
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pm_dev_dbg(dev, state, "legacy ");
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error = dev->bus->resume(dev);
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}
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if (error)
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goto End;
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}
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if (dev->type) {
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if (dev->type->pm) {
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pm_dev_dbg(dev, state, "type ");
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error = pm_op(dev, dev->type->pm, state);
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} else if (dev->type->resume) {
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pm_dev_dbg(dev, state, "legacy type ");
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error = dev->type->resume(dev);
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}
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if (error)
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goto End;
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}
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if (dev->class) {
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if (dev->class->pm) {
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pm_dev_dbg(dev, state, "class ");
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error = pm_op(dev, dev->class->pm, state);
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} else if (dev->class->resume) {
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pm_dev_dbg(dev, state, "legacy class ");
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error = dev->class->resume(dev);
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}
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}
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End:
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up(&dev->sem);
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TRACE_RESUME(error);
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return error;
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}
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/**
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* dpm_resume - Resume every device.
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* @state: PM transition of the system being carried out.
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*
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* Execute the appropriate "resume" callback for all devices the status of
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* which indicates that they are inactive.
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*/
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static void dpm_resume(pm_message_t state)
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{
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struct list_head list;
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INIT_LIST_HEAD(&list);
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mutex_lock(&dpm_list_mtx);
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transition_started = false;
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while (!list_empty(&dpm_list)) {
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struct device *dev = to_device(dpm_list.next);
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get_device(dev);
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if (dev->power.status >= DPM_OFF) {
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int error;
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dev->power.status = DPM_RESUMING;
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mutex_unlock(&dpm_list_mtx);
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error = resume_device(dev, state);
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mutex_lock(&dpm_list_mtx);
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if (error)
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pm_dev_err(dev, state, "", error);
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} else if (dev->power.status == DPM_SUSPENDING) {
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/* Allow new children of the device to be registered */
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dev->power.status = DPM_RESUMING;
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}
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if (!list_empty(&dev->power.entry))
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list_move_tail(&dev->power.entry, &list);
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put_device(dev);
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}
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list_splice(&list, &dpm_list);
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mutex_unlock(&dpm_list_mtx);
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}
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/**
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* complete_device - Complete a PM transition for given device
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* @dev: Device.
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* @state: PM transition of the system being carried out.
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*/
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static void complete_device(struct device *dev, pm_message_t state)
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{
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down(&dev->sem);
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if (dev->class && dev->class->pm && dev->class->pm->complete) {
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pm_dev_dbg(dev, state, "completing class ");
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dev->class->pm->complete(dev);
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}
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if (dev->type && dev->type->pm && dev->type->pm->complete) {
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pm_dev_dbg(dev, state, "completing type ");
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dev->type->pm->complete(dev);
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}
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if (dev->bus && dev->bus->pm && dev->bus->pm->base.complete) {
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pm_dev_dbg(dev, state, "completing ");
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dev->bus->pm->base.complete(dev);
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}
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up(&dev->sem);
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}
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/**
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* dpm_complete - Complete a PM transition for all devices.
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* @state: PM transition of the system being carried out.
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*
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* Execute the ->complete() callbacks for all devices that are not marked
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* as DPM_ON.
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*/
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static void dpm_complete(pm_message_t state)
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{
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struct list_head list;
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INIT_LIST_HEAD(&list);
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mutex_lock(&dpm_list_mtx);
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while (!list_empty(&dpm_list)) {
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struct device *dev = to_device(dpm_list.prev);
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get_device(dev);
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if (dev->power.status > DPM_ON) {
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dev->power.status = DPM_ON;
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mutex_unlock(&dpm_list_mtx);
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complete_device(dev, state);
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mutex_lock(&dpm_list_mtx);
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}
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if (!list_empty(&dev->power.entry))
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list_move(&dev->power.entry, &list);
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put_device(dev);
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}
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list_splice(&list, &dpm_list);
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mutex_unlock(&dpm_list_mtx);
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}
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/**
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* device_resume - Restore state of each device in system.
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* @state: PM transition of the system being carried out.
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*
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* Resume all the devices, unlock them all, and allow new
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* devices to be registered once again.
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*/
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void device_resume(pm_message_t state)
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{
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might_sleep();
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dpm_resume(state);
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dpm_complete(state);
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}
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EXPORT_SYMBOL_GPL(device_resume);
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/*------------------------- Suspend routines -------------------------*/
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|
|
/**
|
|
* resume_event - return a PM message representing the resume event
|
|
* corresponding to given sleep state.
|
|
* @sleep_state: PM message representing a sleep state.
|
|
*/
|
|
static pm_message_t resume_event(pm_message_t sleep_state)
|
|
{
|
|
switch (sleep_state.event) {
|
|
case PM_EVENT_SUSPEND:
|
|
return PMSG_RESUME;
|
|
case PM_EVENT_FREEZE:
|
|
case PM_EVENT_QUIESCE:
|
|
return PMSG_RECOVER;
|
|
case PM_EVENT_HIBERNATE:
|
|
return PMSG_RESTORE;
|
|
}
|
|
return PMSG_ON;
|
|
}
|
|
|
|
/**
|
|
* suspend_device_noirq - Shut down one device (late suspend).
|
|
* @dev: Device.
|
|
* @state: PM transition of the system being carried out.
|
|
*
|
|
* This is called with interrupts off and only a single CPU running.
|
|
*/
|
|
static int suspend_device_noirq(struct device *dev, pm_message_t state)
|
|
{
|
|
int error = 0;
|
|
|
|
if (!dev->bus)
|
|
return 0;
|
|
|
|
if (dev->bus->pm) {
|
|
pm_dev_dbg(dev, state, "LATE ");
|
|
error = pm_noirq_op(dev, dev->bus->pm, state);
|
|
} else if (dev->bus->suspend_late) {
|
|
pm_dev_dbg(dev, state, "legacy LATE ");
|
|
error = dev->bus->suspend_late(dev, state);
|
|
suspend_report_result(dev->bus->suspend_late, error);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* device_power_down - Shut down special devices.
|
|
* @state: PM transition of the system being carried out.
|
|
*
|
|
* Power down devices that require interrupts to be disabled.
|
|
* Then power down system devices.
|
|
*
|
|
* Must be called with interrupts disabled and only one CPU running.
|
|
*/
|
|
int device_power_down(pm_message_t state)
|
|
{
|
|
struct device *dev;
|
|
int error = 0;
|
|
|
|
list_for_each_entry_reverse(dev, &dpm_list, power.entry) {
|
|
error = suspend_device_noirq(dev, state);
|
|
if (error) {
|
|
pm_dev_err(dev, state, " late", error);
|
|
break;
|
|
}
|
|
dev->power.status = DPM_OFF_IRQ;
|
|
}
|
|
if (!error)
|
|
error = sysdev_suspend(state);
|
|
if (error)
|
|
dpm_power_up(resume_event(state));
|
|
return error;
|
|
}
|
|
EXPORT_SYMBOL_GPL(device_power_down);
|
|
|
|
/**
|
|
* suspend_device - Save state of one device.
|
|
* @dev: Device.
|
|
* @state: PM transition of the system being carried out.
|
|
*/
|
|
static int suspend_device(struct device *dev, pm_message_t state)
|
|
{
|
|
int error = 0;
|
|
|
|
down(&dev->sem);
|
|
|
|
if (dev->class) {
|
|
if (dev->class->pm) {
|
|
pm_dev_dbg(dev, state, "class ");
|
|
error = pm_op(dev, dev->class->pm, state);
|
|
} else if (dev->class->suspend) {
|
|
pm_dev_dbg(dev, state, "legacy class ");
|
|
error = dev->class->suspend(dev, state);
|
|
suspend_report_result(dev->class->suspend, error);
|
|
}
|
|
if (error)
|
|
goto End;
|
|
}
|
|
|
|
if (dev->type) {
|
|
if (dev->type->pm) {
|
|
pm_dev_dbg(dev, state, "type ");
|
|
error = pm_op(dev, dev->type->pm, state);
|
|
} else if (dev->type->suspend) {
|
|
pm_dev_dbg(dev, state, "legacy type ");
|
|
error = dev->type->suspend(dev, state);
|
|
suspend_report_result(dev->type->suspend, error);
|
|
}
|
|
if (error)
|
|
goto End;
|
|
}
|
|
|
|
if (dev->bus) {
|
|
if (dev->bus->pm) {
|
|
pm_dev_dbg(dev, state, "");
|
|
error = pm_op(dev, &dev->bus->pm->base, state);
|
|
} else if (dev->bus->suspend) {
|
|
pm_dev_dbg(dev, state, "legacy ");
|
|
error = dev->bus->suspend(dev, state);
|
|
suspend_report_result(dev->bus->suspend, error);
|
|
}
|
|
}
|
|
End:
|
|
up(&dev->sem);
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* dpm_suspend - Suspend every device.
|
|
* @state: PM transition of the system being carried out.
|
|
*
|
|
* Execute the appropriate "suspend" callbacks for all devices.
|
|
*/
|
|
static int dpm_suspend(pm_message_t state)
|
|
{
|
|
struct list_head list;
|
|
int error = 0;
|
|
|
|
INIT_LIST_HEAD(&list);
|
|
mutex_lock(&dpm_list_mtx);
|
|
while (!list_empty(&dpm_list)) {
|
|
struct device *dev = to_device(dpm_list.prev);
|
|
|
|
get_device(dev);
|
|
mutex_unlock(&dpm_list_mtx);
|
|
|
|
error = suspend_device(dev, state);
|
|
|
|
mutex_lock(&dpm_list_mtx);
|
|
if (error) {
|
|
pm_dev_err(dev, state, "", error);
|
|
put_device(dev);
|
|
break;
|
|
}
|
|
dev->power.status = DPM_OFF;
|
|
if (!list_empty(&dev->power.entry))
|
|
list_move(&dev->power.entry, &list);
|
|
put_device(dev);
|
|
}
|
|
list_splice(&list, dpm_list.prev);
|
|
mutex_unlock(&dpm_list_mtx);
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* prepare_device - Execute the ->prepare() callback(s) for given device.
|
|
* @dev: Device.
|
|
* @state: PM transition of the system being carried out.
|
|
*/
|
|
static int prepare_device(struct device *dev, pm_message_t state)
|
|
{
|
|
int error = 0;
|
|
|
|
down(&dev->sem);
|
|
|
|
if (dev->bus && dev->bus->pm && dev->bus->pm->base.prepare) {
|
|
pm_dev_dbg(dev, state, "preparing ");
|
|
error = dev->bus->pm->base.prepare(dev);
|
|
suspend_report_result(dev->bus->pm->base.prepare, error);
|
|
if (error)
|
|
goto End;
|
|
}
|
|
|
|
if (dev->type && dev->type->pm && dev->type->pm->prepare) {
|
|
pm_dev_dbg(dev, state, "preparing type ");
|
|
error = dev->type->pm->prepare(dev);
|
|
suspend_report_result(dev->type->pm->prepare, error);
|
|
if (error)
|
|
goto End;
|
|
}
|
|
|
|
if (dev->class && dev->class->pm && dev->class->pm->prepare) {
|
|
pm_dev_dbg(dev, state, "preparing class ");
|
|
error = dev->class->pm->prepare(dev);
|
|
suspend_report_result(dev->class->pm->prepare, error);
|
|
}
|
|
End:
|
|
up(&dev->sem);
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* dpm_prepare - Prepare all devices for a PM transition.
|
|
* @state: PM transition of the system being carried out.
|
|
*
|
|
* Execute the ->prepare() callback for all devices.
|
|
*/
|
|
static int dpm_prepare(pm_message_t state)
|
|
{
|
|
struct list_head list;
|
|
int error = 0;
|
|
|
|
INIT_LIST_HEAD(&list);
|
|
mutex_lock(&dpm_list_mtx);
|
|
transition_started = true;
|
|
while (!list_empty(&dpm_list)) {
|
|
struct device *dev = to_device(dpm_list.next);
|
|
|
|
get_device(dev);
|
|
dev->power.status = DPM_PREPARING;
|
|
mutex_unlock(&dpm_list_mtx);
|
|
|
|
error = prepare_device(dev, state);
|
|
|
|
mutex_lock(&dpm_list_mtx);
|
|
if (error) {
|
|
dev->power.status = DPM_ON;
|
|
if (error == -EAGAIN) {
|
|
put_device(dev);
|
|
continue;
|
|
}
|
|
printk(KERN_ERR "PM: Failed to prepare device %s "
|
|
"for power transition: error %d\n",
|
|
kobject_name(&dev->kobj), error);
|
|
put_device(dev);
|
|
break;
|
|
}
|
|
dev->power.status = DPM_SUSPENDING;
|
|
if (!list_empty(&dev->power.entry))
|
|
list_move_tail(&dev->power.entry, &list);
|
|
put_device(dev);
|
|
}
|
|
list_splice(&list, &dpm_list);
|
|
mutex_unlock(&dpm_list_mtx);
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* device_suspend - Save state and stop all devices in system.
|
|
* @state: PM transition of the system being carried out.
|
|
*
|
|
* Prepare and suspend all devices.
|
|
*/
|
|
int device_suspend(pm_message_t state)
|
|
{
|
|
int error;
|
|
|
|
might_sleep();
|
|
error = dpm_prepare(state);
|
|
if (!error)
|
|
error = dpm_suspend(state);
|
|
return error;
|
|
}
|
|
EXPORT_SYMBOL_GPL(device_suspend);
|
|
|
|
void __suspend_report_result(const char *function, void *fn, int ret)
|
|
{
|
|
if (ret) {
|
|
printk(KERN_ERR "%s(): ", function);
|
|
print_fn_descriptor_symbol("%s returns ", fn);
|
|
printk("%d\n", ret);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(__suspend_report_result);
|