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authorLinus Torvalds <torvalds@linux-foundation.org>2008-02-02 14:29:57 +1100
committerLinus Torvalds <torvalds@linux-foundation.org>2008-02-02 14:29:57 +1100
commit687fcdf741e4a268c2c7bac8b3734de761bb9719 (patch)
tree82603cd0f892b13d4252cc525ecaec99bb86c0cd /Documentation/power/devices.txt
parent215e871aaa3d94540121a3809d80d0c5e5686e4f (diff)
parenta6eb84bc1e069e1d285167e09035ed6c27978feb (diff)
Merge branch 'suspend' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'suspend' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (38 commits) suspend: cleanup reference to swsusp_pg_dir[] PM: Remove obsolete /sys/devices/.../power/state docs Hibernation: Invoke suspend notifications after console switch Suspend: Invoke suspend notifications after console switch Suspend: Clean up suspend_64.c Suspend: Add config option to disable the freezer if architecture wants that ACPI: Print message before calling _PTS ACPI hibernation: Call _PTS before suspending devices Hibernation: Introduce begin() and end() callbacks ACPI suspend: Call _PTS before suspending devices ACPI: Separate disabling of GPEs from _PTS ACPI: Separate invocations of _GTS and _BFS from _PTS and _WAK Suspend: Introduce begin() and end() callbacks suspend: fix ia64 allmodconfig build ACPI: clear GPE earily in resume to avoid warning Suspend: Clean up Kconfig (V2) Hibernation: Clean up Kconfig (V2) Hibernation: Update messages Suspend: Use common prefix in messages Hibernation: Remove unnecessary variable declaration ...
Diffstat (limited to 'Documentation/power/devices.txt')
-rw-r--r--Documentation/power/devices.txt49
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diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt
index d0e79d5820a..c53d2636191 100644
--- a/Documentation/power/devices.txt
+++ b/Documentation/power/devices.txt
@@ -502,52 +502,3 @@ If the CPU can have a "cpufreq" driver, there also may be opportunities
to shift to lower voltage settings and reduce the power cost of executing
a given number of instructions. (Without voltage adjustment, it's rare
for cpufreq to save much power; the cost-per-instruction must go down.)
-
-
-/sys/devices/.../power/state files
-==================================
-For now you can also test some of this functionality using sysfs.
-
- DEPRECATED: USE "power/state" ONLY FOR DRIVER TESTING, AND
- AVOID USING dev->power.power_state IN DRIVERS.
-
- THESE WILL BE REMOVED. IF THE "power/state" FILE GETS REPLACED,
- IT WILL BECOME SOMETHING COUPLED TO THE BUS OR DRIVER.
-
-In each device's directory, there is a 'power' directory, which contains
-at least a 'state' file. The value of this field is effectively boolean,
-PM_EVENT_ON or PM_EVENT_SUSPEND.
-
- * Reading from this file displays a value corresponding to
- the power.power_state.event field. All nonzero values are
- displayed as "2", corresponding to a low power state; zero
- is displayed as "0", corresponding to normal operation.
-
- * Writing to this file initiates a transition using the
- specified event code number; only '0', '2', and '3' are
- accepted (without a newline); '2' and '3' are both
- mapped to PM_EVENT_SUSPEND.
-
-On writes, the PM core relies on that recorded event code and the device/bus
-capabilities to determine whether it uses a partial suspend() or resume()
-sequence to change things so that the recorded event corresponds to the
-numeric parameter.
-
- - If the bus requires the irqs-disabled suspend_late()/resume_early()
- phases, writes fail because those operations are not supported here.
-
- - If the recorded value is the expected value, nothing is done.
-
- - If the recorded value is nonzero, the device is partially resumed,
- using the bus.resume() and/or class.resume() methods.
-
- - If the target value is nonzero, the device is partially suspended,
- using the class.suspend() and/or bus.suspend() methods and the
- PM_EVENT_SUSPEND message.
-
-Drivers have no way to tell whether their suspend() and resume() calls
-have come through the sysfs power/state file or as part of entering a
-system sleep state, except that when accessed through sysfs the normal
-parent/child sequencing rules are ignored. Drivers (such as bus, bridge,
-or hub drivers) which expose child devices may need to enforce those rules
-on their own.