2 bool "Suspend to RAM and standby"
3 depends on ARCH_SUSPEND_POSSIBLE
7 Allow the system to enter sleep states in which main memory is
8 powered and thus its contents are preserved, such as the
9 suspend-to-RAM state (e.g. the ACPI S3 state).
11 config SUSPEND_FREEZER
12 bool "Enable freezer for suspend to RAM/standby" \
13 if ARCH_WANTS_FREEZER_CONTROL || BROKEN
17 This allows you to turn off the freezer for suspend. If this is
18 done, no tasks are frozen for suspend to RAM/standby.
20 Turning OFF this setting is NOT recommended! If in doubt, say Y.
22 config SUSPEND_SKIP_SYNC
23 bool "Skip kernel's sys_sync() on suspend to RAM/standby"
27 Skip the kernel sys_sync() before freezing user processes.
28 Some systems prefer not to pay this cost on every invocation
29 of suspend, or they are content with invoking sync() from
30 user-space before invoking suspend. Say Y if that's your case.
33 bool "Android's method of preventing suspend"
36 This allows applications to prevent the CPU from suspending while
39 Say Y if you are running an android userspace.
41 config HIBERNATE_CALLBACKS
45 bool "Hibernation (aka 'suspend to disk')"
46 depends on SWAP && ARCH_HIBERNATION_POSSIBLE
47 select HIBERNATE_CALLBACKS
52 Enable the suspend to disk (STD) functionality, which is usually
53 called "hibernation" in user interfaces. STD checkpoints the
54 system and powers it off; and restores that checkpoint on reboot.
56 You can suspend your machine with 'echo disk > /sys/power/state'
57 after placing resume=/dev/swappartition on the kernel command line
58 in your bootloader's configuration file.
60 Alternatively, you can use the additional userland tools available
61 from <http://suspend.sf.net>.
63 In principle it does not require ACPI or APM, although for example
64 ACPI will be used for the final steps when it is available. One
65 of the reasons to use software suspend is that the firmware hooks
66 for suspend states like suspend-to-RAM (STR) often don't work very
69 It creates an image which is saved in your active swap. Upon the next
70 boot, pass the 'resume=/dev/swappartition' argument to the kernel to
71 have it detect the saved image, restore memory state from it, and
72 continue to run as before. If you do not want the previous state to
73 be reloaded, then use the 'noresume' kernel command line argument.
74 Note, however, that fsck will be run on your filesystems and you will
75 need to run mkswap against the swap partition used for the suspend.
77 It also works with swap files to a limited extent (for details see
78 <file:Documentation/power/swsusp-and-swap-files.txt>).
80 Right now you may boot without resuming and resume later but in the
81 meantime you cannot use the swap partition(s)/file(s) involved in
82 suspending. Also in this case you must not use the filesystems
83 that were mounted before the suspend. In particular, you MUST NOT
84 MOUNT any journaled filesystems mounted before the suspend or they
85 will get corrupted in a nasty way.
87 For more information take a look at <file:Documentation/power/swsusp.txt>.
89 config ARCH_SAVE_PAGE_KEYS
92 config PM_STD_PARTITION
93 string "Default resume partition"
94 depends on HIBERNATION
97 The default resume partition is the partition that the suspend-
98 to-disk implementation will look for a suspended disk image.
100 The partition specified here will be different for almost every user.
101 It should be a valid swap partition (at least for now) that is turned
102 on before suspending.
104 The partition specified can be overridden by specifying:
106 resume=/dev/<other device>
108 which will set the resume partition to the device specified.
110 Note there is currently not a way to specify which device to save the
111 suspended image to. It will simply pick the first available swap
116 depends on SUSPEND || HIBERNATE_CALLBACKS
123 depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE
128 bool "Opportunistic sleep"
132 Allow the kernel to trigger a system transition into a global sleep
133 state automatically whenever there are no active wakeup sources.
136 bool "User space wakeup sources interface"
140 Allow user space to create, activate and deactivate wakeup source
141 objects with the help of a sysfs-based interface.
143 config PM_WAKELOCKS_LIMIT
144 int "Maximum number of user space wakeup sources (0 = no limit)"
147 depends on PM_WAKELOCKS
149 config PM_WAKELOCKS_GC
150 bool "Garbage collector for user space wakeup sources"
151 depends on PM_WAKELOCKS
155 bool "Device power management core functionality"
157 Enable functionality allowing I/O devices to be put into energy-saving
158 (low power) states, for example after a specified period of inactivity
159 (autosuspended), and woken up in response to a hardware-generated
160 wake-up event or a driver's request.
162 Hardware support is generally required for this functionality to work
163 and the bus type drivers of the buses the devices are on are
164 responsible for the actual handling of device suspend requests and
168 bool "Power Management Debug Support"
171 This option enables various debugging support in the Power Management
172 code. This is helpful when debugging and reporting PM bugs, like
175 config PM_ADVANCED_DEBUG
176 bool "Extra PM attributes in sysfs for low-level debugging/testing"
179 Add extra sysfs attributes allowing one to access some Power Management
180 fields of device objects from user space. If you are not a kernel
181 developer interested in debugging/testing Power Management, say "no".
183 config PM_TEST_SUSPEND
184 bool "Test suspend/resume and wakealarm during bootup"
185 depends on SUSPEND && PM_DEBUG && RTC_CLASS=y
187 This option will let you suspend your machine during bootup, and
188 make it wake up a few seconds later using an RTC wakeup alarm.
189 Enable this with a kernel parameter like "test_suspend=mem".
191 You probably want to have your system's RTC driver statically
192 linked, ensuring that it's available when this test runs.
194 config PM_SLEEP_DEBUG
196 depends on PM_DEBUG && PM_SLEEP
199 bool "Device suspend/resume watchdog"
200 depends on PM_DEBUG && PSTORE
202 Sets up a watchdog timer to capture drivers that are
203 locked up attempting to suspend/resume a device.
204 A detected lockup causes system panic with message
205 captured in pstore device for inspection in subsequent
208 config DPM_WATCHDOG_TIMEOUT
209 int "Watchdog timeout in seconds"
212 depends on DPM_WATCHDOG
217 This enables code to save the last PM event point across
218 reboot. The architecture needs to support this, x86 for
219 example does by saving things in the RTC, see below.
221 The architecture specific code must provide the extern
222 functions from <linux/resume-trace.h> as well as the
223 <asm/resume-trace.h> header with a TRACE_RESUME() macro.
225 The way the information is presented is architecture-
226 dependent, x86 will print the information during a
230 bool "Suspend/resume event tracing"
231 depends on PM_SLEEP_DEBUG
235 This enables some cheesy code to save the last PM event point in the
236 RTC across reboots, so that you can debug a machine that just hangs
237 during suspend (or more commonly, during resume).
239 To use this debugging feature you should attempt to suspend the
240 machine, reboot it and then run
242 dmesg -s 1000000 | grep 'hash matches'
244 CAUTION: this option will cause your machine's real-time clock to be
245 set to an invalid time after a resume.
248 tristate "Advanced Power Management Emulation"
249 depends on PM && SYS_SUPPORTS_APM_EMULATION
251 APM is a BIOS specification for saving power using several different
252 techniques. This is mostly useful for battery powered laptops with
253 APM compliant BIOSes. If you say Y here, the system time will be
254 reset after a RESUME operation, the /proc/apm device will provide
255 battery status information, and user-space programs will receive
256 notification of APM "events" (e.g. battery status change).
258 In order to use APM, you will need supporting software. For location
259 and more information, read <file:Documentation/power/apm-acpi.txt>
260 and the Battery Powered Linux mini-HOWTO, available from
261 <http://www.tldp.org/docs.html#howto>.
263 This driver does not spin down disk drives (see the hdparm(8)
264 manpage ("man 8 hdparm") for that), and it doesn't turn off
265 VESA-compliant "green" monitors.
267 Generally, if you don't have a battery in your machine, there isn't
268 much point in using this driver and you should say N. If you get
269 random kernel OOPSes or reboots that don't seem to be related to
270 anything, try disabling/enabling this option (or disabling/enabling
277 SOCs have a standard set of tuples consisting of frequency and
278 voltage pairs that the device will support per voltage domain. This
279 is called Operating Performance Point or OPP. The actual definitions
280 of OPP varies over silicon within the same family of devices.
282 OPP layer organizes the data internally using device pointers
283 representing individual voltage domains and provides SOC
284 implementations a ready to use framework to manage OPPs.
285 For more information, read <file:Documentation/power/opp.txt>
289 depends on PM && HAVE_CLK
291 config PM_GENERIC_DOMAINS
295 config WQ_POWER_EFFICIENT_DEFAULT
296 bool "Enable workqueue power-efficient mode by default"
300 Per-cpu workqueues are generally preferred because they show
301 better performance thanks to cache locality; unfortunately,
302 per-cpu workqueues tend to be more power hungry than unbound
305 Enabling workqueue.power_efficient kernel parameter makes the
306 per-cpu workqueues which were observed to contribute
307 significantly to power consumption unbound, leading to measurably
308 lower power usage at the cost of small performance overhead.
310 This config option determines whether workqueue.power_efficient
311 is enabled by default.
315 config PM_GENERIC_DOMAINS_SLEEP
317 depends on PM_SLEEP && PM_GENERIC_DOMAINS
319 config PM_GENERIC_DOMAINS_OF
321 depends on PM_GENERIC_DOMAINS && OF
326 config DEDUCE_WAKEUP_REASONS