alistair23-linux/drivers/acpi/wakeup.c
Rafael J. Wysocki 9b83ccd2f1 ACPI PM: Replace wakeup.prepared with reference counter
The wakeup.prepared flag is used for marking devices that have the
wake-up power already enabled, so that the wake-up power is not
enabled twice in a row for the same device.  This assumes, however,
that device wake-up power will only be enabled once, while the device
is being prepared for a system-wide sleep transition, and the second
attempt is made by acpi_enable_wakeup_device_prep().

With the upcoming PCI wake-up rework this assumption will not hold
any more for PCI bridges and the root bridge whose wake-up power
may be enabled as a result of wake-up enable propagation from other
devices (eg. add-on devices that are not associated with any GPEs).
Thus, there may be many attempts to enable wake-up power on a PCI
bridge or the root bridge during a system power state transition
and it's better to replace wakeup.prepared with a reference counter.

Reviewed-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-09 14:19:18 -07:00

149 lines
4 KiB
C

/*
* wakeup.c - support wakeup devices
* Copyright (C) 2004 Li Shaohua <shaohua.li@intel.com>
*/
#include <linux/init.h>
#include <linux/acpi.h>
#include <acpi/acpi_drivers.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include "internal.h"
#include "sleep.h"
/*
* We didn't lock acpi_device_lock in the file, because it invokes oops in
* suspend/resume and isn't really required as this is called in S-state. At
* that time, there is no device hotplug
**/
#define _COMPONENT ACPI_SYSTEM_COMPONENT
ACPI_MODULE_NAME("wakeup_devices")
/**
* acpi_enable_wakeup_device_prep - prepare wakeup devices
* @sleep_state: ACPI state
* Enable all wakup devices power if the devices' wakeup level
* is higher than requested sleep level
*/
void acpi_enable_wakeup_device_prep(u8 sleep_state)
{
struct list_head *node, *next;
list_for_each_safe(node, next, &acpi_wakeup_device_list) {
struct acpi_device *dev = container_of(node,
struct acpi_device,
wakeup_list);
if (!dev->wakeup.flags.valid ||
!dev->wakeup.state.enabled ||
(sleep_state > (u32) dev->wakeup.sleep_state))
continue;
acpi_enable_wakeup_device_power(dev, sleep_state);
}
}
/**
* acpi_enable_wakeup_device - enable wakeup devices
* @sleep_state: ACPI state
* Enable all wakup devices's GPE
*/
void acpi_enable_wakeup_device(u8 sleep_state)
{
struct list_head *node, *next;
/*
* Caution: this routine must be invoked when interrupt is disabled
* Refer ACPI2.0: P212
*/
list_for_each_safe(node, next, &acpi_wakeup_device_list) {
struct acpi_device *dev =
container_of(node, struct acpi_device, wakeup_list);
if (!dev->wakeup.flags.valid)
continue;
/* If users want to disable run-wake GPE,
* we only disable it for wake and leave it for runtime
*/
if ((!dev->wakeup.state.enabled && !dev->wakeup.prepare_count)
|| sleep_state > (u32) dev->wakeup.sleep_state) {
if (dev->wakeup.flags.run_wake) {
/* set_gpe_type will disable GPE, leave it like that */
acpi_set_gpe_type(dev->wakeup.gpe_device,
dev->wakeup.gpe_number,
ACPI_GPE_TYPE_RUNTIME);
}
continue;
}
if (!dev->wakeup.flags.run_wake)
acpi_enable_gpe(dev->wakeup.gpe_device,
dev->wakeup.gpe_number);
}
}
/**
* acpi_disable_wakeup_device - disable devices' wakeup capability
* @sleep_state: ACPI state
* Disable all wakup devices's GPE and wakeup capability
*/
void acpi_disable_wakeup_device(u8 sleep_state)
{
struct list_head *node, *next;
list_for_each_safe(node, next, &acpi_wakeup_device_list) {
struct acpi_device *dev =
container_of(node, struct acpi_device, wakeup_list);
if (!dev->wakeup.flags.valid)
continue;
if ((!dev->wakeup.state.enabled && !dev->wakeup.prepare_count)
|| sleep_state > (u32) dev->wakeup.sleep_state) {
if (dev->wakeup.flags.run_wake) {
acpi_set_gpe_type(dev->wakeup.gpe_device,
dev->wakeup.gpe_number,
ACPI_GPE_TYPE_WAKE_RUN);
/* Re-enable it, since set_gpe_type will disable it */
acpi_enable_gpe(dev->wakeup.gpe_device,
dev->wakeup.gpe_number);
}
continue;
}
acpi_disable_wakeup_device_power(dev);
/* Never disable run-wake GPE */
if (!dev->wakeup.flags.run_wake) {
acpi_disable_gpe(dev->wakeup.gpe_device,
dev->wakeup.gpe_number);
acpi_clear_gpe(dev->wakeup.gpe_device,
dev->wakeup.gpe_number, ACPI_NOT_ISR);
}
}
}
int __init acpi_wakeup_device_init(void)
{
struct list_head *node, *next;
mutex_lock(&acpi_device_lock);
list_for_each_safe(node, next, &acpi_wakeup_device_list) {
struct acpi_device *dev = container_of(node,
struct acpi_device,
wakeup_list);
/* In case user doesn't load button driver */
if (!dev->wakeup.flags.run_wake || dev->wakeup.state.enabled)
continue;
acpi_set_gpe_type(dev->wakeup.gpe_device,
dev->wakeup.gpe_number,
ACPI_GPE_TYPE_WAKE_RUN);
acpi_enable_gpe(dev->wakeup.gpe_device,
dev->wakeup.gpe_number);
dev->wakeup.state.enabled = 1;
}
mutex_unlock(&acpi_device_lock);
return 0;
}