1config SUSPEND 2 bool "Suspend to RAM and standby" 3 depends on ARCH_SUSPEND_POSSIBLE 4 default y 5 ---help--- 6 Allow the system to enter sleep states in which main memory is 7 powered and thus its contents are preserved, such as the 8 suspend-to-RAM state (e.g. the ACPI S3 state). 9 10config SUSPEND_FREEZER 11 bool "Enable freezer for suspend to RAM/standby" \ 12 if ARCH_WANTS_FREEZER_CONTROL || BROKEN 13 depends on SUSPEND 14 default y 15 help 16 This allows you to turn off the freezer for suspend. If this is 17 done, no tasks are frozen for suspend to RAM/standby. 18 19 Turning OFF this setting is NOT recommended! If in doubt, say Y. 20 21config SUSPEND_SKIP_SYNC 22 bool "Skip kernel's sys_sync() on suspend to RAM/standby" 23 depends on SUSPEND 24 depends on EXPERT 25 help 26 Skip the kernel sys_sync() before freezing user processes. 27 Some systems prefer not to pay this cost on every invocation 28 of suspend, or they are content with invoking sync() from 29 user-space before invoking suspend. Say Y if that's your case. 30 31config HIBERNATE_CALLBACKS 32 bool 33 34config HIBERNATION 35 bool "Hibernation (aka 'suspend to disk')" 36 depends on SWAP && ARCH_HIBERNATION_POSSIBLE 37 select HIBERNATE_CALLBACKS 38 select LZO_COMPRESS 39 select LZO_DECOMPRESS 40 select CRC32 41 ---help--- 42 Enable the suspend to disk (STD) functionality, which is usually 43 called "hibernation" in user interfaces. STD checkpoints the 44 system and powers it off; and restores that checkpoint on reboot. 45 46 You can suspend your machine with 'echo disk > /sys/power/state' 47 after placing resume=/dev/swappartition on the kernel command line 48 in your bootloader's configuration file. 49 50 Alternatively, you can use the additional userland tools available 51 from <http://suspend.sf.net>. 52 53 In principle it does not require ACPI or APM, although for example 54 ACPI will be used for the final steps when it is available. One 55 of the reasons to use software suspend is that the firmware hooks 56 for suspend states like suspend-to-RAM (STR) often don't work very 57 well with Linux. 58 59 It creates an image which is saved in your active swap. Upon the next 60 boot, pass the 'resume=/dev/swappartition' argument to the kernel to 61 have it detect the saved image, restore memory state from it, and 62 continue to run as before. If you do not want the previous state to 63 be reloaded, then use the 'noresume' kernel command line argument. 64 Note, however, that fsck will be run on your filesystems and you will 65 need to run mkswap against the swap partition used for the suspend. 66 67 It also works with swap files to a limited extent (for details see 68 <file:Documentation/power/swsusp-and-swap-files.txt>). 69 70 Right now you may boot without resuming and resume later but in the 71 meantime you cannot use the swap partition(s)/file(s) involved in 72 suspending. Also in this case you must not use the filesystems 73 that were mounted before the suspend. In particular, you MUST NOT 74 MOUNT any journaled filesystems mounted before the suspend or they 75 will get corrupted in a nasty way. 76 77 For more information take a look at <file:Documentation/power/swsusp.txt>. 78 79config ARCH_SAVE_PAGE_KEYS 80 bool 81 82config PM_STD_PARTITION 83 string "Default resume partition" 84 depends on HIBERNATION 85 default "" 86 ---help--- 87 The default resume partition is the partition that the suspend- 88 to-disk implementation will look for a suspended disk image. 89 90 The partition specified here will be different for almost every user. 91 It should be a valid swap partition (at least for now) that is turned 92 on before suspending. 93 94 The partition specified can be overridden by specifying: 95 96 resume=/dev/<other device> 97 98 which will set the resume partition to the device specified. 99 100 Note there is currently not a way to specify which device to save the 101 suspended image to. It will simply pick the first available swap 102 device. 103 104config PM_SLEEP 105 def_bool y 106 depends on SUSPEND || HIBERNATE_CALLBACKS 107 select PM 108 109config PM_SLEEP_SMP 110 def_bool y 111 depends on SMP 112 depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE 113 depends on PM_SLEEP 114 select HOTPLUG_CPU 115 116config PM_AUTOSLEEP 117 bool "Opportunistic sleep" 118 depends on PM_SLEEP 119 default n 120 ---help--- 121 Allow the kernel to trigger a system transition into a global sleep 122 state automatically whenever there are no active wakeup sources. 123 124config PM_WAKELOCKS 125 bool "User space wakeup sources interface" 126 depends on PM_SLEEP 127 default n 128 ---help--- 129 Allow user space to create, activate and deactivate wakeup source 130 objects with the help of a sysfs-based interface. 131 132config PM_WAKELOCKS_LIMIT 133 int "Maximum number of user space wakeup sources (0 = no limit)" 134 range 0 100000 135 default 100 136 depends on PM_WAKELOCKS 137 138config PM_WAKELOCKS_GC 139 bool "Garbage collector for user space wakeup sources" 140 depends on PM_WAKELOCKS 141 default y 142 143config PM 144 bool "Device power management core functionality" 145 ---help--- 146 Enable functionality allowing I/O devices to be put into energy-saving 147 (low power) states, for example after a specified period of inactivity 148 (autosuspended), and woken up in response to a hardware-generated 149 wake-up event or a driver's request. 150 151 Hardware support is generally required for this functionality to work 152 and the bus type drivers of the buses the devices are on are 153 responsible for the actual handling of device suspend requests and 154 wake-up events. 155 156config PM_DEBUG 157 bool "Power Management Debug Support" 158 depends on PM 159 ---help--- 160 This option enables various debugging support in the Power Management 161 code. This is helpful when debugging and reporting PM bugs, like 162 suspend support. 163 164config PM_ADVANCED_DEBUG 165 bool "Extra PM attributes in sysfs for low-level debugging/testing" 166 depends on PM_DEBUG 167 ---help--- 168 Add extra sysfs attributes allowing one to access some Power Management 169 fields of device objects from user space. If you are not a kernel 170 developer interested in debugging/testing Power Management, say "no". 171 172config PM_TEST_SUSPEND 173 bool "Test suspend/resume and wakealarm during bootup" 174 depends on SUSPEND && PM_DEBUG && RTC_CLASS=y 175 ---help--- 176 This option will let you suspend your machine during bootup, and 177 make it wake up a few seconds later using an RTC wakeup alarm. 178 Enable this with a kernel parameter like "test_suspend=mem". 179 180 You probably want to have your system's RTC driver statically 181 linked, ensuring that it's available when this test runs. 182 183config PM_SLEEP_DEBUG 184 def_bool y 185 depends on PM_DEBUG && PM_SLEEP 186 187config DPM_WATCHDOG 188 bool "Device suspend/resume watchdog" 189 depends on PM_DEBUG && PSTORE && EXPERT 190 ---help--- 191 Sets up a watchdog timer to capture drivers that are 192 locked up attempting to suspend/resume a device. 193 A detected lockup causes system panic with message 194 captured in pstore device for inspection in subsequent 195 boot session. 196 197config DPM_WATCHDOG_TIMEOUT 198 int "Watchdog timeout in seconds" 199 range 1 120 200 default 120 201 depends on DPM_WATCHDOG 202 203config PM_TRACE 204 bool 205 help 206 This enables code to save the last PM event point across 207 reboot. The architecture needs to support this, x86 for 208 example does by saving things in the RTC, see below. 209 210 The architecture specific code must provide the extern 211 functions from <linux/resume-trace.h> as well as the 212 <asm/resume-trace.h> header with a TRACE_RESUME() macro. 213 214 The way the information is presented is architecture- 215 dependent, x86 will print the information during a 216 late_initcall. 217 218config PM_TRACE_RTC 219 bool "Suspend/resume event tracing" 220 depends on PM_SLEEP_DEBUG 221 depends on X86 222 select PM_TRACE 223 ---help--- 224 This enables some cheesy code to save the last PM event point in the 225 RTC across reboots, so that you can debug a machine that just hangs 226 during suspend (or more commonly, during resume). 227 228 To use this debugging feature you should attempt to suspend the 229 machine, reboot it and then run 230 231 dmesg -s 1000000 | grep 'hash matches' 232 233 CAUTION: this option will cause your machine's real-time clock to be 234 set to an invalid time after a resume. 235 236config APM_EMULATION 237 tristate "Advanced Power Management Emulation" 238 depends on SYS_SUPPORTS_APM_EMULATION 239 help 240 APM is a BIOS specification for saving power using several different 241 techniques. This is mostly useful for battery powered laptops with 242 APM compliant BIOSes. If you say Y here, the system time will be 243 reset after a RESUME operation, the /proc/apm device will provide 244 battery status information, and user-space programs will receive 245 notification of APM "events" (e.g. battery status change). 246 247 In order to use APM, you will need supporting software. For location 248 and more information, read <file:Documentation/power/apm-acpi.txt> 249 and the Battery Powered Linux mini-HOWTO, available from 250 <http://www.tldp.org/docs.html#howto>. 251 252 This driver does not spin down disk drives (see the hdparm(8) 253 manpage ("man 8 hdparm") for that), and it doesn't turn off 254 VESA-compliant "green" monitors. 255 256 Generally, if you don't have a battery in your machine, there isn't 257 much point in using this driver and you should say N. If you get 258 random kernel OOPSes or reboots that don't seem to be related to 259 anything, try disabling/enabling this option (or disabling/enabling 260 APM in your BIOS). 261 262config PM_OPP 263 bool 264 select SRCU 265 ---help--- 266 SOCs have a standard set of tuples consisting of frequency and 267 voltage pairs that the device will support per voltage domain. This 268 is called Operating Performance Point or OPP. The actual definitions 269 of OPP varies over silicon within the same family of devices. 270 271 OPP layer organizes the data internally using device pointers 272 representing individual voltage domains and provides SOC 273 implementations a ready to use framework to manage OPPs. 274 For more information, read <file:Documentation/power/opp.txt> 275 276config PM_CLK 277 def_bool y 278 depends on PM && HAVE_CLK 279 280config PM_GENERIC_DOMAINS 281 bool 282 depends on PM 283 284config WQ_POWER_EFFICIENT_DEFAULT 285 bool "Enable workqueue power-efficient mode by default" 286 depends on PM 287 default n 288 help 289 Per-cpu workqueues are generally preferred because they show 290 better performance thanks to cache locality; unfortunately, 291 per-cpu workqueues tend to be more power hungry than unbound 292 workqueues. 293 294 Enabling workqueue.power_efficient kernel parameter makes the 295 per-cpu workqueues which were observed to contribute 296 significantly to power consumption unbound, leading to measurably 297 lower power usage at the cost of small performance overhead. 298 299 This config option determines whether workqueue.power_efficient 300 is enabled by default. 301 302 If in doubt, say N. 303 304config PM_GENERIC_DOMAINS_SLEEP 305 def_bool y 306 depends on PM_SLEEP && PM_GENERIC_DOMAINS 307 308config PM_GENERIC_DOMAINS_OF 309 def_bool y 310 depends on PM_GENERIC_DOMAINS && OF 311 312config CPU_PM 313 bool 314