| /* |
| * drivers/base/power/main.c - Where the driver meets power management. |
| * |
| * Copyright (c) 2003 Patrick Mochel |
| * Copyright (c) 2003 Open Source Development Lab |
| * |
| * This file is released under the GPLv2 |
| * |
| * |
| * The driver model core calls device_pm_add() when a device is registered. |
| * This will intialize the embedded device_pm_info object in the device |
| * and add it to the list of power-controlled devices. sysfs entries for |
| * controlling device power management will also be added. |
| * |
| * A different set of lists than the global subsystem list are used to |
| * keep track of power info because we use different lists to hold |
| * devices based on what stage of the power management process they |
| * are in. The power domain dependencies may also differ from the |
| * ancestral dependencies that the subsystem list maintains. |
| */ |
| |
| #include <linux/device.h> |
| #include "power.h" |
| |
| LIST_HEAD(dpm_active); |
| LIST_HEAD(dpm_off); |
| LIST_HEAD(dpm_off_irq); |
| |
| DECLARE_MUTEX(dpm_sem); |
| DECLARE_MUTEX(dpm_list_sem); |
| |
| /** |
| * device_pm_set_parent - Specify power dependency. |
| * @dev: Device who needs power. |
| * @parent: Device that supplies power. |
| * |
| * This function is used to manually describe a power-dependency |
| * relationship. It may be used to specify a transversal relationship |
| * (where the power supplier is not the physical (or electrical) |
| * ancestor of a specific device. |
| * The effect of this is that the supplier will not be powered down |
| * before the power dependent. |
| */ |
| |
| void device_pm_set_parent(struct device * dev, struct device * parent) |
| { |
| put_device(dev->power.pm_parent); |
| dev->power.pm_parent = get_device(parent); |
| } |
| EXPORT_SYMBOL_GPL(device_pm_set_parent); |
| |
| int device_pm_add(struct device * dev) |
| { |
| int error; |
| |
| pr_debug("PM: Adding info for %s:%s\n", |
| dev->bus ? dev->bus->name : "No Bus", |
| kobject_name(&dev->kobj)); |
| down(&dpm_list_sem); |
| list_add_tail(&dev->power.entry, &dpm_active); |
| device_pm_set_parent(dev, dev->parent); |
| if ((error = dpm_sysfs_add(dev))) |
| list_del(&dev->power.entry); |
| up(&dpm_list_sem); |
| return error; |
| } |
| |
| void device_pm_remove(struct device * dev) |
| { |
| pr_debug("PM: Removing info for %s:%s\n", |
| dev->bus ? dev->bus->name : "No Bus", |
| kobject_name(&dev->kobj)); |
| down(&dpm_list_sem); |
| dpm_sysfs_remove(dev); |
| put_device(dev->power.pm_parent); |
| list_del_init(&dev->power.entry); |
| up(&dpm_list_sem); |
| } |
| |
| |