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authorPaul Mundt <lethal@linux-sh.org>2011-05-23 11:35:33 +0900
committerPaul Mundt <lethal@linux-sh.org>2011-05-23 11:35:33 +0900
commit8ace5c4698ec8da53e69095596718d5a936433de (patch)
tree1f5959b3ac289e3bde420cc14109be0cc518a75a /Documentation/power/devices.txt
parenta375b15164dd9264f724ad941825e52c90145151 (diff)
parent71a8638480eb8fb6cfabe2ee9ca3fbc6e3453a14 (diff)
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into sh-latest
Diffstat (limited to 'Documentation/power/devices.txt')
-rw-r--r--Documentation/power/devices.txt14
1 files changed, 9 insertions, 5 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt
index 1971bcf48a6..88880839ece 100644
--- a/Documentation/power/devices.txt
+++ b/Documentation/power/devices.txt
@@ -279,11 +279,15 @@ When the system goes into the standby or memory sleep state, the phases are:
time.) Unlike the other suspend-related phases, during the prepare
phase the device tree is traversed top-down.
- The prepare phase uses only a bus callback. After the callback method
- returns, no new children may be registered below the device. The method
- may also prepare the device or driver in some way for the upcoming
- system power transition, but it should not put the device into a
- low-power state.
+ In addition to that, if device drivers need to allocate additional
+ memory to be able to hadle device suspend correctly, that should be
+ done in the prepare phase.
+
+ After the prepare callback method returns, no new children may be
+ registered below the device. The method may also prepare the device or
+ driver in some way for the upcoming system power transition (for
+ example, by allocating additional memory required for this purpose), but
+ it should not put the device into a low-power state.
2. The suspend methods should quiesce the device to stop it from performing
I/O. They also may save the device registers and put it into the