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authorRafael J. Wysocki <rjw@sisk.pl>2009-09-08 23:15:31 +0200
committerJesse Barnes <jbarnes@virtuousgeek.org>2009-09-09 14:19:18 -0700
commit9b83ccd2f14f647936dcfbf4a9a20c501007dd69 (patch)
treebc405d4c14635ff309a5f39c905ede40fc762916 /drivers/acpi/power.c
parente80bb09d2c73d76a2a4cd79e4a83802dd901c642 (diff)
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>
Diffstat (limited to 'drivers/acpi/power.c')
-rw-r--r--drivers/acpi/power.c58
1 files changed, 35 insertions, 23 deletions
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index d74365d4a6e..5a09bf392ec 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -44,6 +44,8 @@
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
+#include "sleep.h"
+
#define _COMPONENT ACPI_POWER_COMPONENT
ACPI_MODULE_NAME("power");
#define ACPI_POWER_CLASS "power_resource"
@@ -361,17 +363,15 @@ int acpi_device_sleep_wake(struct acpi_device *dev,
*/
int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
{
- int i, err;
+ int i, err = 0;
if (!dev || !dev->wakeup.flags.valid)
return -EINVAL;
- /*
- * Do not execute the code below twice in a row without calling
- * acpi_disable_wakeup_device_power() in between for the same device
- */
- if (dev->wakeup.flags.prepared)
- return 0;
+ mutex_lock(&acpi_device_lock);
+
+ if (dev->wakeup.prepare_count++)
+ goto out;
/* Open power resource */
for (i = 0; i < dev->wakeup.resources.count; i++) {
@@ -379,7 +379,8 @@ int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
if (ret) {
printk(KERN_ERR PREFIX "Transition power state\n");
dev->wakeup.flags.valid = 0;
- return -ENODEV;
+ err = -ENODEV;
+ goto err_out;
}
}
@@ -388,9 +389,13 @@ int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
* in arbitrary power state afterwards.
*/
err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
- if (!err)
- dev->wakeup.flags.prepared = 1;
+ err_out:
+ if (err)
+ dev->wakeup.prepare_count = 0;
+
+ out:
+ mutex_unlock(&acpi_device_lock);
return err;
}
@@ -402,35 +407,42 @@ int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
*/
int acpi_disable_wakeup_device_power(struct acpi_device *dev)
{
- int i, ret;
+ int i, err = 0;
if (!dev || !dev->wakeup.flags.valid)
return -EINVAL;
+ mutex_lock(&acpi_device_lock);
+
+ if (--dev->wakeup.prepare_count > 0)
+ goto out;
+
/*
- * Do not execute the code below twice in a row without calling
- * acpi_enable_wakeup_device_power() in between for the same device
+ * Executing the code below even if prepare_count is already zero when
+ * the function is called may be useful, for example for initialisation.
*/
- if (!dev->wakeup.flags.prepared)
- return 0;
+ if (dev->wakeup.prepare_count < 0)
+ dev->wakeup.prepare_count = 0;
- dev->wakeup.flags.prepared = 0;
-
- ret = acpi_device_sleep_wake(dev, 0, 0, 0);
- if (ret)
- return ret;
+ err = acpi_device_sleep_wake(dev, 0, 0, 0);
+ if (err)
+ goto out;
/* Close power resource */
for (i = 0; i < dev->wakeup.resources.count; i++) {
- ret = acpi_power_off_device(dev->wakeup.resources.handles[i], dev);
+ int ret = acpi_power_off_device(
+ dev->wakeup.resources.handles[i], dev);
if (ret) {
printk(KERN_ERR PREFIX "Transition power state\n");
dev->wakeup.flags.valid = 0;
- return -ENODEV;
+ err = -ENODEV;
+ goto out;
}
}
- return ret;
+ out:
+ mutex_unlock(&acpi_device_lock);
+ return err;
}
/* --------------------------------------------------------------------------