sending the processor to sleep and saving power.
config PM_LEGACY
- bool "Legacy Power Management API"
+ bool "Legacy Power Management API (DEPRECATED)"
depends on PM
- default y
+ default n
---help---
- Support for pm_register() and friends.
+ Support for pm_register() and friends. This old API is obsoleted
+ by the driver model.
- If unsure, say Y.
+ If unsure, say N.
config PM_DEBUG
bool "Power Management Debug Support"
code. This is helpful when debugging and reporting various PM bugs,
like suspend support.
+config DISABLE_CONSOLE_SUSPEND
+ bool "Keep console(s) enabled during suspend/resume (DANGEROUS)"
+ depends on PM && PM_DEBUG
+ default n
+ ---help---
+ This option turns off the console suspend mechanism that prevents
+ debug messages from reaching the console during the suspend/resume
+ operations. This may be helpful when debugging device drivers'
+ suspend/resume routines, but may itself lead to problems, for example
+ if netconsole is used.
+
+config PM_TRACE
+ bool "Suspend/resume event tracing"
+ depends on PM && PM_DEBUG && X86_32 && EXPERIMENTAL
+ default n
+ ---help---
+ This enables some cheesy code to save the last PM event point in the
+ RTC across reboots, so that you can debug a machine that just hangs
+ during suspend (or more commonly, during resume).
+
+ To use this debugging feature you should attempt to suspend the machine,
+ then reboot it, then run
+
+ dmesg -s 1000000 | grep 'hash matches'
+
+ CAUTION: this option will cause your machine's real-time clock to be
+ set to an invalid time after a resume.
+
+config PM_SYSFS_DEPRECATED
+ bool "Driver model /sys/devices/.../power/state files (DEPRECATED)"
+ depends on PM && SYSFS
+ default n
+ help
+ The driver model started out with a sysfs file intended to provide
+ a userspace hook for device power management. This feature has never
+ worked very well, except for limited testing purposes, and so it will
+ be removed. It's not clear that a generic mechanism could really
+ handle the wide variability of device power states; any replacements
+ are likely to be bus or driver specific.
+
config SOFTWARE_SUSPEND
- bool "Software Suspend"
- depends on PM && SWAP && (X86 && (!SMP || SUSPEND_SMP)) || ((FRV || PPC32) && !SMP)
+ bool "Software Suspend (Hibernation)"
+ depends on PM && SWAP && (((X86 || PPC64_SWSUSP) && (!SMP || SUSPEND_SMP)) || ((FRV || PPC32) && !SMP))
---help---
- Enable the possibility of suspending the machine.
- It doesn't need APM.
- You may suspend your machine by 'swsusp' or 'shutdown -z <time>'
- (patch for sysvinit needed).
+ Enable the suspend to disk (STD) functionality, which is usually
+ called "hibernation" in user interfaces. STD checkpoints the
+ system and powers it off; and restores that checkpoint on reboot.
- It creates an image which is saved in your active swap. Upon next
+ You can suspend your machine with 'echo disk > /sys/power/state'.
+ Alternatively, you can use the additional userland tools available
+ from <http://suspend.sf.net>.
+
+ In principle it does not require ACPI or APM, although for example
+ ACPI will be used for the final steps when it is available. One
+ of the reasons to use software suspend is that the firmware hooks
+ for suspend states like suspend-to-RAM (STR) often don't work very
+ well with Linux.
+
+ It creates an image which is saved in your active swap. Upon the next
boot, pass the 'resume=/dev/swappartition' argument to the kernel to
have it detect the saved image, restore memory state from it, and
continue to run as before. If you do not want the previous state to
- be reloaded, then use the 'noresume' kernel argument. However, note
- that your partitions will be fsck'd and you must re-mkswap your swap
- partitions. It does not work with swap files.
+ be reloaded, then use the 'noresume' kernel command line argument.
+ Note, however, that fsck will be run on your filesystems and you will
+ need to run mkswap against the swap partition used for the suspend.
- Right now you may boot without resuming and then later resume but
- in meantime you cannot use those swap partitions/files which were
- involved in suspending. Also in this case there is a risk that buffers
- on disk won't match with saved ones.
+ It also works with swap files to a limited extent (for details see
+ <file:Documentation/power/swsusp-and-swap-files.txt>).
+
+ Right now you may boot without resuming and resume later but in the
+ meantime you cannot use the swap partition(s)/file(s) involved in
+ suspending. Also in this case you must not use the filesystems
+ that were mounted before the suspend. In particular, you MUST NOT
+ MOUNT any journaled filesystems mounted before the suspend or they
+ will get corrupted in a nasty way.
For more information take a look at <file:Documentation/power/swsusp.txt>.
suspended image to. It will simply pick the first available swap
device.
-config SWSUSP_ENCRYPT
- bool "Encrypt suspend image"
- depends on SOFTWARE_SUSPEND && CRYPTO=y && (CRYPTO_AES=y || CRYPTO_AES_586=y || CRYPTO_AES_X86_64=y)
- default ""
- ---help---
- To prevent data gathering from swap after resume you can encrypt
- the suspend image with a temporary key that is deleted on
- resume.
-
- Note that the temporary key is stored unencrypted on disk while the
- system is suspended.
-
config SUSPEND_SMP
bool
- depends on HOTPLUG_CPU && X86 && PM
+ depends on HOTPLUG_CPU && (X86 || PPC64) && PM
default y
+
+config APM_EMULATION
+ tristate "Advanced Power Management Emulation"
+ depends on PM && SYS_SUPPORTS_APM_EMULATION
+ help
+ APM is a BIOS specification for saving power using several different
+ techniques. This is mostly useful for battery powered laptops with
+ APM compliant BIOSes. If you say Y here, the system time will be
+ reset after a RESUME operation, the /proc/apm device will provide
+ battery status information, and user-space programs will receive
+ notification of APM "events" (e.g. battery status change).
+
+ In order to use APM, you will need supporting software. For location
+ and more information, read <file:Documentation/pm.txt> and the
+ Battery Powered Linux mini-HOWTO, available from
+ <http://www.tldp.org/docs.html#howto>.
+
+ This driver does not spin down disk drives (see the hdparm(8)
+ manpage ("man 8 hdparm") for that), and it doesn't turn off
+ VESA-compliant "green" monitors.
+
+ Generally, if you don't have a battery in your machine, there isn't
+ much point in using this driver and you should say N. If you get
+ random kernel OOPSes or reboots that don't seem to be related to
+ anything, try disabling/enabling this option (or disabling/enabling
+ APM in your BIOS).
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff