diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/base/power/suspend.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/base/power/suspend.c')
-rw-r--r-- | drivers/base/power/suspend.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/drivers/base/power/suspend.c b/drivers/base/power/suspend.c new file mode 100644 index 000000000000..a0b5cf689e63 --- /dev/null +++ b/drivers/base/power/suspend.c | |||
@@ -0,0 +1,144 @@ | |||
1 | /* | ||
2 | * suspend.c - Functions for putting devices to sleep. | ||
3 | * | ||
4 | * Copyright (c) 2003 Patrick Mochel | ||
5 | * Copyright (c) 2003 Open Source Development Labs | ||
6 | * | ||
7 | * This file is released under the GPLv2 | ||
8 | * | ||
9 | */ | ||
10 | |||
11 | #include <linux/device.h> | ||
12 | #include "power.h" | ||
13 | |||
14 | extern int sysdev_suspend(pm_message_t state); | ||
15 | |||
16 | /* | ||
17 | * The entries in the dpm_active list are in a depth first order, simply | ||
18 | * because children are guaranteed to be discovered after parents, and | ||
19 | * are inserted at the back of the list on discovery. | ||
20 | * | ||
21 | * All list on the suspend path are done in reverse order, so we operate | ||
22 | * on the leaves of the device tree (or forests, depending on how you want | ||
23 | * to look at it ;) first. As nodes are removed from the back of the list, | ||
24 | * they are inserted into the front of their destintation lists. | ||
25 | * | ||
26 | * Things are the reverse on the resume path - iterations are done in | ||
27 | * forward order, and nodes are inserted at the back of their destination | ||
28 | * lists. This way, the ancestors will be accessed before their descendents. | ||
29 | */ | ||
30 | |||
31 | |||
32 | /** | ||
33 | * suspend_device - Save state of one device. | ||
34 | * @dev: Device. | ||
35 | * @state: Power state device is entering. | ||
36 | */ | ||
37 | |||
38 | int suspend_device(struct device * dev, pm_message_t state) | ||
39 | { | ||
40 | int error = 0; | ||
41 | |||
42 | dev_dbg(dev, "suspending\n"); | ||
43 | |||
44 | dev->power.prev_state = dev->power.power_state; | ||
45 | |||
46 | if (dev->bus && dev->bus->suspend && !dev->power.power_state) | ||
47 | error = dev->bus->suspend(dev, state); | ||
48 | |||
49 | return error; | ||
50 | } | ||
51 | |||
52 | |||
53 | /** | ||
54 | * device_suspend - Save state and stop all devices in system. | ||
55 | * @state: Power state to put each device in. | ||
56 | * | ||
57 | * Walk the dpm_active list, call ->suspend() for each device, and move | ||
58 | * it to dpm_off. | ||
59 | * Check the return value for each. If it returns 0, then we move the | ||
60 | * the device to the dpm_off list. If it returns -EAGAIN, we move it to | ||
61 | * the dpm_off_irq list. If we get a different error, try and back out. | ||
62 | * | ||
63 | * If we hit a failure with any of the devices, call device_resume() | ||
64 | * above to bring the suspended devices back to life. | ||
65 | * | ||
66 | */ | ||
67 | |||
68 | int device_suspend(pm_message_t state) | ||
69 | { | ||
70 | int error = 0; | ||
71 | |||
72 | down(&dpm_sem); | ||
73 | down(&dpm_list_sem); | ||
74 | while (!list_empty(&dpm_active) && error == 0) { | ||
75 | struct list_head * entry = dpm_active.prev; | ||
76 | struct device * dev = to_device(entry); | ||
77 | |||
78 | get_device(dev); | ||
79 | up(&dpm_list_sem); | ||
80 | |||
81 | error = suspend_device(dev, state); | ||
82 | |||
83 | down(&dpm_list_sem); | ||
84 | |||
85 | /* Check if the device got removed */ | ||
86 | if (!list_empty(&dev->power.entry)) { | ||
87 | /* Move it to the dpm_off or dpm_off_irq list */ | ||
88 | if (!error) { | ||
89 | list_del(&dev->power.entry); | ||
90 | list_add(&dev->power.entry, &dpm_off); | ||
91 | } else if (error == -EAGAIN) { | ||
92 | list_del(&dev->power.entry); | ||
93 | list_add(&dev->power.entry, &dpm_off_irq); | ||
94 | error = 0; | ||
95 | } | ||
96 | } | ||
97 | if (error) | ||
98 | printk(KERN_ERR "Could not suspend device %s: " | ||
99 | "error %d\n", kobject_name(&dev->kobj), error); | ||
100 | put_device(dev); | ||
101 | } | ||
102 | up(&dpm_list_sem); | ||
103 | if (error) | ||
104 | dpm_resume(); | ||
105 | up(&dpm_sem); | ||
106 | return error; | ||
107 | } | ||
108 | |||
109 | EXPORT_SYMBOL_GPL(device_suspend); | ||
110 | |||
111 | |||
112 | /** | ||
113 | * device_power_down - Shut down special devices. | ||
114 | * @state: Power state to enter. | ||
115 | * | ||
116 | * Walk the dpm_off_irq list, calling ->power_down() for each device that | ||
117 | * couldn't power down the device with interrupts enabled. When we're | ||
118 | * done, power down system devices. | ||
119 | */ | ||
120 | |||
121 | int device_power_down(pm_message_t state) | ||
122 | { | ||
123 | int error = 0; | ||
124 | struct device * dev; | ||
125 | |||
126 | list_for_each_entry_reverse(dev, &dpm_off_irq, power.entry) { | ||
127 | if ((error = suspend_device(dev, state))) | ||
128 | break; | ||
129 | } | ||
130 | if (error) | ||
131 | goto Error; | ||
132 | if ((error = sysdev_suspend(state))) | ||
133 | goto Error; | ||
134 | Done: | ||
135 | return error; | ||
136 | Error: | ||
137 | printk(KERN_ERR "Could not power down device %s: " | ||
138 | "error %d\n", kobject_name(&dev->kobj), error); | ||
139 | dpm_power_up(); | ||
140 | goto Done; | ||
141 | } | ||
142 | |||
143 | EXPORT_SYMBOL_GPL(device_power_down); | ||
144 | |||