diff options
Diffstat (limited to 'drivers/acpi/device_pm.c')
-rw-r--r-- | drivers/acpi/device_pm.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c new file mode 100644 index 0000000..2d2e0bc --- /dev/null +++ b/drivers/acpi/device_pm.c @@ -0,0 +1,91 @@ +/* + * drivers/acpi/device_pm.c - ACPI device power management routines. + * + * Copyright (C) 2012, Intel Corp. + * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + */ + +#include <linux/device.h> +#include <linux/mutex.h> + +#include <acpi/acpi.h> +#include <acpi/acpi_bus.h> + +static DEFINE_MUTEX(acpi_pm_notifier_lock); + +/** + * acpi_add_pm_notifier - Register PM notifier for given ACPI device. + * @adev: ACPI device to add the notifier for. + * @context: Context information to pass to the notifier routine. + * + * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of + * PM wakeup events. For example, wakeup events may be generated for bridges + * if one of the devices below the bridge is signaling wakeup, even if the + * bridge itself doesn't have a wakeup GPE associated with it. + */ +acpi_status acpi_add_pm_notifier(struct acpi_device *adev, + acpi_notify_handler handler, void *context) +{ + acpi_status status = AE_ALREADY_EXISTS; + + mutex_lock(&acpi_pm_notifier_lock); + + if (adev->wakeup.flags.notifier_present) + goto out; + + status = acpi_install_notify_handler(adev->handle, + ACPI_SYSTEM_NOTIFY, + handler, context); + if (ACPI_FAILURE(status)) + goto out; + + adev->wakeup.flags.notifier_present = true; + + out: + mutex_unlock(&acpi_pm_notifier_lock); + return status; +} + +/** + * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device. + * @adev: ACPI device to remove the notifier from. + */ +acpi_status acpi_remove_pm_notifier(struct acpi_device *adev, + acpi_notify_handler handler) +{ + acpi_status status = AE_BAD_PARAMETER; + + mutex_lock(&acpi_pm_notifier_lock); + + if (!adev->wakeup.flags.notifier_present) + goto out; + + status = acpi_remove_notify_handler(adev->handle, + ACPI_SYSTEM_NOTIFY, + handler); + if (ACPI_FAILURE(status)) + goto out; + + adev->wakeup.flags.notifier_present = false; + + out: + mutex_unlock(&acpi_pm_notifier_lock); + return status; +} |