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 HIBERNATION 22 bool "Hibernation (aka 'suspend to disk')" 23 depends on SWAP && ARCH_HIBERNATION_POSSIBLE 24 select LZO_COMPRESS 25 select LZO_DECOMPRESS 26 ---help--- 27 Enable the suspend to disk (STD) functionality, which is usually 28 called "hibernation" in user interfaces. STD checkpoints the 29 system and powers it off; and restores that checkpoint on reboot. 30 31 You can suspend your machine with 'echo disk > /sys/power/state' 32 after placing resume=/dev/swappartition on the kernel command line 33 in your bootloader's configuration file. 34 35 Alternatively, you can use the additional userland tools available 36 from <http://suspend.sf.net>. 37 38 In principle it does not require ACPI or APM, although for example 39 ACPI will be used for the final steps when it is available. One 40 of the reasons to use software suspend is that the firmware hooks 41 for suspend states like suspend-to-RAM (STR) often don't work very 42 well with Linux. 43 44 It creates an image which is saved in your active swap. Upon the next 45 boot, pass the 'resume=/dev/swappartition' argument to the kernel to 46 have it detect the saved image, restore memory state from it, and 47 continue to run as before. If you do not want the previous state to 48 be reloaded, then use the 'noresume' kernel command line argument. 49 Note, however, that fsck will be run on your filesystems and you will 50 need to run mkswap against the swap partition used for the suspend. 51 52 It also works with swap files to a limited extent (for details see 53 <file:Documentation/power/swsusp-and-swap-files.txt>). 54 55 Right now you may boot without resuming and resume later but in the 56 meantime you cannot use the swap partition(s)/file(s) involved in 57 suspending. Also in this case you must not use the filesystems 58 that were mounted before the suspend. In particular, you MUST NOT 59 MOUNT any journaled filesystems mounted before the suspend or they 60 will get corrupted in a nasty way. 61 62 For more information take a look at <file:Documentation/power/swsusp.txt>. 63 64config PM_STD_PARTITION 65 string "Default resume partition" 66 depends on HIBERNATION 67 default "" 68 ---help--- 69 The default resume partition is the partition that the suspend- 70 to-disk implementation will look for a suspended disk image. 71 72 The partition specified here will be different for almost every user. 73 It should be a valid swap partition (at least for now) that is turned 74 on before suspending. 75 76 The partition specified can be overridden by specifying: 77 78 resume=/dev/<other device> 79 80 which will set the resume partition to the device specified. 81 82 Note there is currently not a way to specify which device to save the 83 suspended image to. It will simply pick the first available swap 84 device. 85 86config PM_SLEEP 87 def_bool y 88 depends on SUSPEND || HIBERNATION || XEN_SAVE_RESTORE 89 90config PM_SLEEP_SMP 91 def_bool y 92 depends on SMP 93 depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE 94 depends on PM_SLEEP 95 select HOTPLUG 96 select HOTPLUG_CPU 97 98config PM_RUNTIME 99 bool "Run-time PM core functionality" 100 depends on !IA64_HP_SIM 101 ---help--- 102 Enable functionality allowing I/O devices to be put into energy-saving 103 (low power) states at run time (or autosuspended) after a specified 104 period of inactivity and woken up in response to a hardware-generated 105 wake-up event or a driver's request. 106 107 Hardware support is generally required for this functionality to work 108 and the bus type drivers of the buses the devices are on are 109 responsible for the actual handling of the autosuspend requests and 110 wake-up events. 111 112config PM 113 def_bool y 114 depends on PM_SLEEP || PM_RUNTIME 115 116config PM_DEBUG 117 bool "Power Management Debug Support" 118 depends on PM 119 ---help--- 120 This option enables various debugging support in the Power Management 121 code. This is helpful when debugging and reporting PM bugs, like 122 suspend support. 123 124config PM_VERBOSE 125 bool "Verbose Power Management debugging" 126 depends on PM_DEBUG 127 ---help--- 128 This option enables verbose messages from the Power Management code. 129 130config PM_ADVANCED_DEBUG 131 bool "Extra PM attributes in sysfs for low-level debugging/testing" 132 depends on PM_DEBUG 133 ---help--- 134 Add extra sysfs attributes allowing one to access some Power Management 135 fields of device objects from user space. If you are not a kernel 136 developer interested in debugging/testing Power Management, say "no". 137 138config PM_TEST_SUSPEND 139 bool "Test suspend/resume and wakealarm during bootup" 140 depends on SUSPEND && PM_DEBUG && RTC_CLASS=y 141 ---help--- 142 This option will let you suspend your machine during bootup, and 143 make it wake up a few seconds later using an RTC wakeup alarm. 144 Enable this with a kernel parameter like "test_suspend=mem". 145 146 You probably want to have your system's RTC driver statically 147 linked, ensuring that it's available when this test runs. 148 149config CAN_PM_TRACE 150 def_bool y 151 depends on PM_DEBUG && PM_SLEEP 152 153config PM_TRACE 154 bool 155 help 156 This enables code to save the last PM event point across 157 reboot. The architecture needs to support this, x86 for 158 example does by saving things in the RTC, see below. 159 160 The architecture specific code must provide the extern 161 functions from <linux/resume-trace.h> as well as the 162 <asm/resume-trace.h> header with a TRACE_RESUME() macro. 163 164 The way the information is presented is architecture- 165 dependent, x86 will print the information during a 166 late_initcall. 167 168config PM_TRACE_RTC 169 bool "Suspend/resume event tracing" 170 depends on CAN_PM_TRACE 171 depends on X86 172 select PM_TRACE 173 ---help--- 174 This enables some cheesy code to save the last PM event point in the 175 RTC across reboots, so that you can debug a machine that just hangs 176 during suspend (or more commonly, during resume). 177 178 To use this debugging feature you should attempt to suspend the 179 machine, reboot it and then run 180 181 dmesg -s 1000000 | grep 'hash matches' 182 183 CAUTION: this option will cause your machine's real-time clock to be 184 set to an invalid time after a resume. 185 186config APM_EMULATION 187 tristate "Advanced Power Management Emulation" 188 depends on PM && SYS_SUPPORTS_APM_EMULATION 189 help 190 APM is a BIOS specification for saving power using several different 191 techniques. This is mostly useful for battery powered laptops with 192 APM compliant BIOSes. If you say Y here, the system time will be 193 reset after a RESUME operation, the /proc/apm device will provide 194 battery status information, and user-space programs will receive 195 notification of APM "events" (e.g. battery status change). 196 197 In order to use APM, you will need supporting software. For location 198 and more information, read <file:Documentation/power/pm.txt> and the 199 Battery Powered Linux mini-HOWTO, available from 200 <http://www.tldp.org/docs.html#howto>. 201 202 This driver does not spin down disk drives (see the hdparm(8) 203 manpage ("man 8 hdparm") for that), and it doesn't turn off 204 VESA-compliant "green" monitors. 205 206 Generally, if you don't have a battery in your machine, there isn't 207 much point in using this driver and you should say N. If you get 208 random kernel OOPSes or reboots that don't seem to be related to 209 anything, try disabling/enabling this option (or disabling/enabling 210 APM in your BIOS). 211 212config ARCH_HAS_OPP 213 bool 214 215config PM_OPP 216 bool "Operating Performance Point (OPP) Layer library" 217 depends on ARCH_HAS_OPP 218 ---help--- 219 SOCs have a standard set of tuples consisting of frequency and 220 voltage pairs that the device will support per voltage domain. This 221 is called Operating Performance Point or OPP. The actual definitions 222 of OPP varies over silicon within the same family of devices. 223 224 OPP layer organizes the data internally using device pointers 225 representing individual voltage domains and provides SOC 226 implementations a ready to use framework to manage OPPs. 227 For more information, read <file:Documentation/power/opp.txt> 228