From 9b83ccd2f14f647936dcfbf4a9a20c501007dd69 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 8 Sep 2009 23:15:31 +0200 Subject: 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 Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes --- drivers/acpi/power.c | 58 +++++++++++++++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 23 deletions(-) (limited to 'drivers/acpi/power.c') 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 #include +#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; } /* -------------------------------------------------------------------------- -- cgit v1.2.3