1/*
2 * drivers/base/power/runtime.c - Handling dynamic device power management.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 *
7 */
8
9#include <linux/device.h>
10#include "power.h"
11
12
13static void runtime_resume(struct device * dev)
14{
15	dev_dbg(dev, "resuming\n");
16	if (!dev->power.power_state.event)
17		return;
18	if (!resume_device(dev))
19		dev->power.power_state = PMSG_ON;
20}
21
22
23
24void dpm_runtime_resume(struct device * dev)
25{
26	down(&dpm_sem);
27	runtime_resume(dev);
28	up(&dpm_sem);
29}
30EXPORT_SYMBOL(dpm_runtime_resume);
31
32
33/**
34 *	dpm_runtime_suspend - Put one device in low-power state.
35 *	@dev:	Device.
36 *	@state:	State to enter.
37 */
38
39int dpm_runtime_suspend(struct device * dev, pm_message_t state)
40{
41	int error = 0;
42
43	down(&dpm_sem);
44	if (dev->power.power_state.event == state.event)
45		goto Done;
46
47	if (dev->power.power_state.event)
48		runtime_resume(dev);
49
50	if (!(error = suspend_device(dev, state)))
51		dev->power.power_state = state;
52 Done:
53	up(&dpm_sem);
54	return error;
55}
56EXPORT_SYMBOL(dpm_runtime_suspend);
57