OpenCloudOS-Kernel/drivers/base/power/resume.c

150 lines
2.8 KiB
C

/*
* resume.c - Functions for waking devices up.
*
* Copyright (c) 2003 Patrick Mochel
* Copyright (c) 2003 Open Source Development Labs
*
* This file is released under the GPLv2
*
*/
#include <linux/device.h>
#include <linux/resume-trace.h>
#include "../base.h"
#include "power.h"
/**
* resume_device - Restore state for one device.
* @dev: Device.
*
*/
int resume_device(struct device * dev)
{
int error = 0;
TRACE_DEVICE(dev);
TRACE_RESUME(0);
down(&dev->sem);
if (dev->bus && dev->bus->resume) {
dev_dbg(dev,"resuming\n");
error = dev->bus->resume(dev);
}
if (!error && dev->type && dev->type->resume) {
dev_dbg(dev,"resuming\n");
error = dev->type->resume(dev);
}
if (!error && dev->class && dev->class->resume) {
dev_dbg(dev,"class resume\n");
error = dev->class->resume(dev);
}
up(&dev->sem);
TRACE_RESUME(error);
return error;
}
static int resume_device_early(struct device * dev)
{
int error = 0;
TRACE_DEVICE(dev);
TRACE_RESUME(0);
if (dev->bus && dev->bus->resume_early) {
dev_dbg(dev,"EARLY resume\n");
error = dev->bus->resume_early(dev);
}
TRACE_RESUME(error);
return error;
}
/*
* Resume the devices that have either not gone through
* the late suspend, or that did go through it but also
* went through the early resume
*/
void dpm_resume(void)
{
mutex_lock(&dpm_list_mtx);
while(!list_empty(&dpm_off)) {
struct list_head * entry = dpm_off.next;
struct device * dev = to_device(entry);
get_device(dev);
list_move_tail(entry, &dpm_active);
mutex_unlock(&dpm_list_mtx);
resume_device(dev);
mutex_lock(&dpm_list_mtx);
put_device(dev);
}
mutex_unlock(&dpm_list_mtx);
}
/**
* device_resume - Restore state of each device in system.
*
* Walk the dpm_off list, remove each entry, resume the device,
* then add it to the dpm_active list.
*/
void device_resume(void)
{
might_sleep();
mutex_lock(&dpm_mtx);
dpm_resume();
mutex_unlock(&dpm_mtx);
}
EXPORT_SYMBOL_GPL(device_resume);
/**
* dpm_power_up - Power on some devices.
*
* Walk the dpm_off_irq list and power each device up. This
* is used for devices that required they be powered down with
* interrupts disabled. As devices are powered on, they are moved
* to the dpm_active list.
*
* Interrupts must be disabled when calling this.
*/
void dpm_power_up(void)
{
while(!list_empty(&dpm_off_irq)) {
struct list_head * entry = dpm_off_irq.next;
struct device * dev = to_device(entry);
list_move_tail(entry, &dpm_off);
resume_device_early(dev);
}
}
/**
* device_power_up - Turn on all devices that need special attention.
*
* Power on system devices then devices that required we shut them down
* with interrupts disabled.
* Called with interrupts disabled.
*/
void device_power_up(void)
{
sysdev_resume();
dpm_power_up();
}
EXPORT_SYMBOL_GPL(device_power_up);