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authorTrond Myklebust <Trond.Myklebust@netapp.com>2006-06-24 16:41:41 +0400
committerTrond Myklebust <Trond.Myklebust@netapp.com>2006-06-24 21:07:53 +0400
commit816724e65c72a90a44fbad0ef0b59b186c85fa90 (patch)
tree421fa29aedff988e392f92780637553e275d37a0 /Documentation/power/devices.txt
parent70ac4385a13f78bc478f26d317511893741b05bd (diff)
parentd384ea691fe4ea8c2dd5b9b8d9042eb181776f18 (diff)
downloadlinux-816724e65c72a90a44fbad0ef0b59b186c85fa90.tar.xz
Merge branch 'master' of /home/trondmy/kernel/linux-2.6/
Conflicts: fs/nfs/inode.c fs/super.c Fix conflicts between patch 'NFS: Split fs/nfs/inode.c' and patch 'VFS: Permit filesystem to override root dentry on mount'
Diffstat (limited to 'Documentation/power/devices.txt')
-rw-r--r--Documentation/power/devices.txt90
1 files changed, 0 insertions, 90 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt
index f987afe43e28..fba1e05c47c7 100644
--- a/Documentation/power/devices.txt
+++ b/Documentation/power/devices.txt
@@ -135,96 +135,6 @@ HW.
FREEZE -- stop DMA and interrupts, and be prepared to reinit HW from
scratch. That probably means stop accepting upstream requests, the
-actual policy of what to do with them beeing specific to a given
-driver. It's acceptable for a network driver to just drop packets
-while a block driver is expected to block the queue so no request is
-lost. (Use IDE as an example on how to do that). FREEZE requires no
-power state change, and it's expected for drivers to be able to
-quickly transition back to operating state.
-
-SUSPEND -- like FREEZE, but also put hardware into low-power state. If
-there's need to distinguish several levels of sleep, additional flag
-is probably best way to do that.
-
-Transitions are only from a resumed state to a suspended state, never
-between 2 suspended states. (ON -> FREEZE or ON -> SUSPEND can happen,
-FREEZE -> SUSPEND or SUSPEND -> FREEZE can not).
-
-All events are:
-
-[NOTE NOTE NOTE: If you are driver author, you should not care; you
-should only look at event, and ignore flags.]
-
-#Prepare for suspend -- userland is still running but we are going to
-#enter suspend state. This gives drivers chance to load firmware from
-#disk and store it in memory, or do other activities taht require
-#operating userland, ability to kmalloc GFP_KERNEL, etc... All of these
-#are forbiden once the suspend dance is started.. event = ON, flags =
-#PREPARE_TO_SUSPEND
-
-Apm standby -- prepare for APM event. Quiesce devices to make life
-easier for APM BIOS. event = FREEZE, flags = APM_STANDBY
-
-Apm suspend -- same as APM_STANDBY, but it we should probably avoid
-spinning down disks. event = FREEZE, flags = APM_SUSPEND
-
-System halt, reboot -- quiesce devices to make life easier for BIOS. event
-= FREEZE, flags = SYSTEM_HALT or SYSTEM_REBOOT
-
-System shutdown -- at least disks need to be spun down, or data may be
-lost. Quiesce devices, just to make life easier for BIOS. event =
-FREEZE, flags = SYSTEM_SHUTDOWN
-
-Kexec -- turn off DMAs and put hardware into some state where new
-kernel can take over. event = FREEZE, flags = KEXEC
-
-Powerdown at end of swsusp -- very similar to SYSTEM_SHUTDOWN, except wake
-may need to be enabled on some devices. This actually has at least 3
-subtypes, system can reboot, enter S4 and enter S5 at the end of
-swsusp. event = FREEZE, flags = SWSUSP and one of SYSTEM_REBOOT,
-SYSTEM_SHUTDOWN, SYSTEM_S4
-
-Suspend to ram -- put devices into low power state. event = SUSPEND,
-flags = SUSPEND_TO_RAM
-
-Freeze for swsusp snapshot -- stop DMA and interrupts. No need to put
-devices into low power mode, but you must be able to reinitialize
-device from scratch in resume method. This has two flavors, its done
-once on suspending kernel, once on resuming kernel. event = FREEZE,
-flags = DURING_SUSPEND or DURING_RESUME
-
-Device detach requested from /sys -- deinitialize device; proably same as
-SYSTEM_SHUTDOWN, I do not understand this one too much. probably event
-= FREEZE, flags = DEV_DETACH.
-
-#These are not really events sent:
-#
-#System fully on -- device is working normally; this is probably never
-#passed to suspend() method... event = ON, flags = 0
-#
-#Ready after resume -- userland is now running, again. Time to free any
-#memory you ate during prepare to suspend... event = ON, flags =
-#READY_AFTER_RESUME
-#
-
-
-pm_message_t meaning
-
-pm_message_t has two fields. event ("major"), and flags. If driver
-does not know event code, it aborts the request, returning error. Some
-drivers may need to deal with special cases based on the actual type
-of suspend operation being done at the system level. This is why
-there are flags.
-
-Event codes are:
-
-ON -- no need to do anything except special cases like broken
-HW.
-
-# NOTIFICATION -- pretty much same as ON?
-
-FREEZE -- stop DMA and interrupts, and be prepared to reinit HW from
-scratch. That probably means stop accepting upstream requests, the
actual policy of what to do with them being specific to a given
driver. It's acceptable for a network driver to just drop packets
while a block driver is expected to block the queue so no request is