linux-toradex.git/drivers/base/power/power.h, branch v2.6.32.31

PM: Introduce core framework for run-time PM of I/O devices (rev. 17)

2009-08-22T22:04:44+00:00

Introduce a core framework for run-time power management of I/O
devices.  Add device run-time PM fields to 'struct dev_pm_info'
and device run-time PM callbacks to 'struct dev_pm_ops'.  Introduce
a run-time PM workqueue and define some device run-time PM helper
functions at the core level.  Document all these things.

Special thanks to Alan Stern for his help with the design and
multiple detailed reviews of the pereceding versions of this patch
and to Magnus Damm for testing feedback.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Magnus Damm

Driver core: Fix device_move() vs. dpm list ordering, v2

2009-03-24T23:38:26+00:00

dpm_list currently relies on the fact that child devices will
be registered after their parents to get a correct suspend
order. Using device_move() however destroys this assumption, as
an already registered device may be moved under a newly registered
one.

This patch adds a new argument to device_move(), allowing callers
to specify how dpm_list should be adapted.

Signed-off-by: Cornelia Huck 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

PM: don't skip device PM init when CONFIG_PM_SLEEP isn't set and CONFIG_PM is set

2008-08-21T17:15:36+00:00

This patch (as1124) fixes a couple of bugs in the PM core.  The new
dev->power.status field should be initialized regardless of whether
CONFIG_PM_SLEEP is enabled, and similarly dpm_sysfs_add() should be
called whenever CONFIG_PM is enabled.

The patch separates out the call to dpm_sysfs_add() from the call to
device_pm_add().  As a result device_pm_add() can no longer return an
error, so its return type is changed to void.

Signed-off-by: Alan Stern 
Tested-by: Romit Dasgupta 
Acked-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

Introduce new top level suspend and hibernation callbacks

2008-06-10T17:59:50+00:00

Introduce 'struct pm_ops' and 'struct pm_ext_ops' ('ext' meaning
'extended') representing suspend and hibernation operations for bus
types, device classes, device types and device drivers.

Modify the PM core to use 'struct pm_ops' and 'struct pm_ext_ops'
objects, if defined, instead of the ->suspend(), ->resume(),
->suspend_late(), and ->resume_early() callbacks (the old callbacks
will be considered as legacy and gradually phased out).

The main purpose of doing this is to separate suspend (aka S2RAM and
standby) callbacks from hibernation callbacks in such a way that the
new callbacks won't take arguments and the semantics of each of them
will be clearly specified.  This has been requested for multiple
times by many people, including Linus himself, and the reason is that
within the current scheme if ->resume() is called, for example, it's
difficult to say why it's been called (ie. is it a resume from RAM or
from hibernation or a suspend/hibernation failure etc.?).

The second purpose is to make the suspend/hibernation callbacks more
flexible so that device drivers can handle more than they can within
the current scheme.  For example, some drivers may need to prevent
new children of the device from being registered before their
->suspend() callbacks are executed or they may want to carry out some
operations requiring the availability of some other devices, not
directly bound via the parent-child relationship, in order to prepare
for the execution of ->suspend(), etc.

Ultimately, we'd like to stop using the freezing of tasks for suspend
and therefore the drivers' suspend/hibernation code will have to take
care of the handling of the user space during suspend/hibernation.
That, in turn, would be difficult within the current scheme, without
the new ->prepare() and ->complete() callbacks.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Signed-off-by: Jesse Barnes

PM: Handle device registrations during suspend/resume

2008-04-20T02:10:24+00:00

Modify the PM core to protect its data structures, specifically the
dpm_active list, from being corrupted if a child of the currently
suspending device is registered concurrently with its ->suspend()
callback.  In that case, since the new device (the child) is added
to dpm_active after its parent, the PM core will attempt to
suspend it after the parent, which is wrong.

Introduce a new member of struct dev_pm_info, called 'sleeping',
and use it to check if the parent of the device being added to
dpm_active has been suspended, in which case the device registration
fails.  Also, use 'sleeping' for checking if the ordering of devices
on dpm_active is correct.

Introduce variable 'all_sleeping' that will be set to 'true' once all
devices have been suspended and make new device registrations fail
until 'all_sleeping' is reset to 'false', in order to avoid having
unsuspended devices around while the system is going into a sleep state.

Remove pm_sleep_rwsem which is not necessary any more.

Special thanks to Alan Stern for discussions and suggestions that
lead to the creation of this patch.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Signed-off-by: Greg Kroah-Hartman

PM: Export device_pm_schedule_removal

2008-02-02T23:14:48+00:00

Move the declaration of device_pm_schedule_removal() to device.h
and make it exported, as it will be used directly by some drivers
for unregistering device objects during suspend/resume cycles in a
safe way.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Signed-off-by: Greg Kroah-Hartman

driver core: clean up shutdown.c

2008-01-25T04:40:25+00:00

shutdown.c had some stuff it did not need, including a duplicate extern
in the power.h file.  This cleans up all of that.


Signed-off-by: Greg Kroah-Hartman

PM: Acquire device locks on suspend

2008-01-25T04:40:04+00:00

This patch reorganizes the way suspend and resume notifications are
sent to drivers.  The major changes are that now the PM core acquires
every device semaphore before calling the methods, and calls to
device_add() during suspends will fail, while calls to device_del()
during suspends will block.

It also provides a way to safely remove a suspended device with the
help of the PM core, by using the device_pm_schedule_removal() callback
introduced specifically for this purpose, and updates two drivers (msr
and cpuid) that need to use it.

Signed-off-by: Alan Stern 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

create /sys/.../power when CONFIG_PM is set

2007-11-28T21:53:53+00:00

The CONFIG_SUSPEND changes in 2.6.23 caused a regression under certain
configuration conditions (SUSPEND=n, USB_AUTOSUSPEND=y) where all USB
device attributes in sysfs (idVendor, idProduct, ...) silently disappeared,
causing udev breakage and more.

The cause of this is that the /sys/.../power subdirectory is now only
created when CONFIG_PM_SLEEP is set, however, it should be created whenever
CONFIG_PM is set to handle the above situation.  The following patch fixes
the regression.

Signed-off-by: Daniel Drake 
Acked-by: Rafael J. Wysocki 
Cc: Alan Stern 
Cc: Kay Sievers 
Cc: stable 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

PM: merge device power-management source files

2007-10-12T21:51:12+00:00

This patch (as993) merges the suspend.c and resume.c files in
drivers/base/power into main.c, making some public symbols private.

Signed-off-by: Alan Stern 
Acked-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman