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 HIBERNATE_CALLBACKS 22 bool 23 24config HIBERNATION 25 bool "Hibernation (aka 'suspend to disk')" 26 depends on SWAP && ARCH_HIBERNATION_POSSIBLE 27 select HIBERNATE_CALLBACKS 28 select LZO_COMPRESS 29 select LZO_DECOMPRESS 30 select CRC32 31 ---help--- 32 Enable the suspend to disk (STD) functionality, which is usually 33 called "hibernation" in user interfaces. STD checkpoints the 34 system and powers it off; and restores that checkpoint on reboot. 35 36 You can suspend your machine with 'echo disk > /sys/power/state' 37 after placing resume=/dev/swappartition on the kernel command line 38 in your bootloader's configuration file. 39 40 Alternatively, you can use the additional userland tools available 41 from <http://suspend.sf.net>. 42 43 In principle it does not require ACPI or APM, although for example 44 ACPI will be used for the final steps when it is available. One 45 of the reasons to use software suspend is that the firmware hooks 46 for suspend states like suspend-to-RAM (STR) often don't work very 47 well with Linux. 48 49 It creates an image which is saved in your active swap. Upon the next 50 boot, pass the 'resume=/dev/swappartition' argument to the kernel to 51 have it detect the saved image, restore memory state from it, and 52 continue to run as before. If you do not want the previous state to 53 be reloaded, then use the 'noresume' kernel command line argument. 54 Note, however, that fsck will be run on your filesystems and you will 55 need to run mkswap against the swap partition used for the suspend. 56 57 It also works with swap files to a limited extent (for details see 58 <file:Documentation/power/swsusp-and-swap-files.txt>). 59 60 Right now you may boot without resuming and resume later but in the 61 meantime you cannot use the swap partition(s)/file(s) involved in 62 suspending. Also in this case you must not use the filesystems 63 that were mounted before the suspend. In particular, you MUST NOT 64 MOUNT any journaled filesystems mounted before the suspend or they 65 will get corrupted in a nasty way. 66 67 For more information take a look at <file:Documentation/power/swsusp.txt>. 68 69config ARCH_SAVE_PAGE_KEYS 70 bool 71 72config PM_STD_PARTITION 73 string "Default resume partition" 74 depends on HIBERNATION 75 default "" 76 ---help--- 77 The default resume partition is the partition that the suspend- 78 to-disk implementation will look for a suspended disk image. 79 80 The partition specified here will be different for almost every user. 81 It should be a valid swap partition (at least for now) that is turned 82 on before suspending. 83 84 The partition specified can be overridden by specifying: 85 86 resume=/dev/<other device> 87 88 which will set the resume partition to the device specified. 89 90 Note there is currently not a way to specify which device to save the 91 suspended image to. It will simply pick the first available swap 92 device. 93 94config PM_SLEEP 95 def_bool y 96 depends on SUSPEND || HIBERNATE_CALLBACKS 97 98config PM_SLEEP_SMP 99 def_bool y 100 depends on SMP 101 depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE 102 depends on PM_SLEEP 103 select HOTPLUG_CPU 104 105config PM_AUTOSLEEP 106 bool "Opportunistic sleep" 107 depends on PM_SLEEP 108 default n 109 ---help--- 110 Allow the kernel to trigger a system transition into a global sleep 111 state automatically whenever there are no active wakeup sources. 112 113config PM_WAKELOCKS 114 bool "User space wakeup sources interface" 115 depends on PM_SLEEP 116 default n 117 ---help--- 118 Allow user space to create, activate and deactivate wakeup source 119 objects with the help of a sysfs-based interface. 120 121config PM_WAKELOCKS_LIMIT 122 int "Maximum number of user space wakeup sources (0 = no limit)" 123 range 0 100000 124 default 100 125 depends on PM_WAKELOCKS 126 127config PM_WAKELOCKS_GC 128 bool "Garbage collector for user space wakeup sources" 129 depends on PM_WAKELOCKS 130 default y 131 132config PM_RUNTIME 133 bool "Run-time PM core functionality" 134 depends on !IA64_HP_SIM 135 ---help--- 136 Enable functionality allowing I/O devices to be put into energy-saving 137 (low power) states at run time (or autosuspended) after a specified 138 period of inactivity and woken up in response to a hardware-generated 139 wake-up event or a driver's request. 140 141 Hardware support is generally required for this functionality to work 142 and the bus type drivers of the buses the devices are on are 143 responsible for the actual handling of the autosuspend requests and 144 wake-up events. 145 146config PM 147 def_bool y 148 depends on PM_SLEEP || PM_RUNTIME 149 150config PM_DEBUG 151 bool "Power Management Debug Support" 152 depends on PM 153 ---help--- 154 This option enables various debugging support in the Power Management 155 code. This is helpful when debugging and reporting PM bugs, like 156 suspend support. 157 158config PM_ADVANCED_DEBUG 159 bool "Extra PM attributes in sysfs for low-level debugging/testing" 160 depends on PM_DEBUG 161 ---help--- 162 Add extra sysfs attributes allowing one to access some Power Management 163 fields of device objects from user space. If you are not a kernel 164 developer interested in debugging/testing Power Management, say "no". 165 166config PM_TEST_SUSPEND 167 bool "Test suspend/resume and wakealarm during bootup" 168 depends on SUSPEND && PM_DEBUG && RTC_CLASS=y 169 ---help--- 170 This option will let you suspend your machine during bootup, and 171 make it wake up a few seconds later using an RTC wakeup alarm. 172 Enable this with a kernel parameter like "test_suspend=mem". 173 174 You probably want to have your system's RTC driver statically 175 linked, ensuring that it's available when this test runs. 176 177config PM_SLEEP_DEBUG 178 def_bool y 179 depends on PM_DEBUG && PM_SLEEP 180 181config DPM_WATCHDOG 182 bool "Device suspend/resume watchdog" 183 depends on PM_DEBUG && PSTORE 184 ---help--- 185 Sets up a watchdog timer to capture drivers that are 186 locked up attempting to suspend/resume a device. 187 A detected lockup causes system panic with message 188 captured in pstore device for inspection in subsequent 189 boot session. 190 191config DPM_WATCHDOG_TIMEOUT 192 int "Watchdog timeout in seconds" 193 range 1 120 194 default 12 195 depends on DPM_WATCHDOG 196 197config PM_TRACE 198 bool 199 help 200 This enables code to save the last PM event point across 201 reboot. The architecture needs to support this, x86 for 202 example does by saving things in the RTC, see below. 203 204 The architecture specific code must provide the extern 205 functions from <linux/resume-trace.h> as well as the 206 <asm/resume-trace.h> header with a TRACE_RESUME() macro. 207 208 The way the information is presented is architecture- 209 dependent, x86 will print the information during a 210 late_initcall. 211 212config PM_TRACE_RTC 213 bool "Suspend/resume event tracing" 214 depends on PM_SLEEP_DEBUG 215 depends on X86 216 select PM_TRACE 217 ---help--- 218 This enables some cheesy code to save the last PM event point in the 219 RTC across reboots, so that you can debug a machine that just hangs 220 during suspend (or more commonly, during resume). 221 222 To use this debugging feature you should attempt to suspend the 223 machine, reboot it and then run 224 225 dmesg -s 1000000 | grep 'hash matches' 226 227 CAUTION: this option will cause your machine's real-time clock to be 228 set to an invalid time after a resume. 229 230config APM_EMULATION 231 tristate "Advanced Power Management Emulation" 232 depends on PM && SYS_SUPPORTS_APM_EMULATION 233 help 234 APM is a BIOS specification for saving power using several different 235 techniques. This is mostly useful for battery powered laptops with 236 APM compliant BIOSes. If you say Y here, the system time will be 237 reset after a RESUME operation, the /proc/apm device will provide 238 battery status information, and user-space programs will receive 239 notification of APM "events" (e.g. battery status change). 240 241 In order to use APM, you will need supporting software. For location 242 and more information, read <file:Documentation/power/apm-acpi.txt> 243 and the Battery Powered Linux mini-HOWTO, available from 244 <http://www.tldp.org/docs.html#howto>. 245 246 This driver does not spin down disk drives (see the hdparm(8) 247 manpage ("man 8 hdparm") for that), and it doesn't turn off 248 VESA-compliant "green" monitors. 249 250 Generally, if you don't have a battery in your machine, there isn't 251 much point in using this driver and you should say N. If you get 252 random kernel OOPSes or reboots that don't seem to be related to 253 anything, try disabling/enabling this option (or disabling/enabling 254 APM in your BIOS). 255 256config ARCH_HAS_OPP 257 bool 258 259config PM_OPP 260 bool "Operating Performance Point (OPP) Layer library" 261 depends on ARCH_HAS_OPP 262 ---help--- 263 SOCs have a standard set of tuples consisting of frequency and 264 voltage pairs that the device will support per voltage domain. This 265 is called Operating Performance Point or OPP. The actual definitions 266 of OPP varies over silicon within the same family of devices. 267 268 OPP layer organizes the data internally using device pointers 269 representing individual voltage domains and provides SOC 270 implementations a ready to use framework to manage OPPs. 271 For more information, read <file:Documentation/power/opp.txt> 272 273config PM_CLK 274 def_bool y 275 depends on PM && HAVE_CLK 276 277config PM_GENERIC_DOMAINS 278 bool 279 depends on PM 280 281config WQ_POWER_EFFICIENT_DEFAULT 282 bool "Enable workqueue power-efficient mode by default" 283 depends on PM 284 default n 285 help 286 Per-cpu workqueues are generally preferred because they show 287 better performance thanks to cache locality; unfortunately, 288 per-cpu workqueues tend to be more power hungry than unbound 289 workqueues. 290 291 Enabling workqueue.power_efficient kernel parameter makes the 292 per-cpu workqueues which were observed to contribute 293 significantly to power consumption unbound, leading to measurably 294 lower power usage at the cost of small performance overhead. 295 296 This config option determines whether workqueue.power_efficient 297 is enabled by default. 298 299 If in doubt, say N. 300 301config PM_GENERIC_DOMAINS_SLEEP 302 def_bool y 303 depends on PM_SLEEP && PM_GENERIC_DOMAINS 304 305config PM_GENERIC_DOMAINS_RUNTIME 306 def_bool y 307 depends on PM_RUNTIME && PM_GENERIC_DOMAINS 308 309config CPU_PM 310 bool 311 depends on SUSPEND || CPU_IDLE 312