Commit Graph

23 Commits

Author SHA1 Message Date
Rafael J. Wysocki ec4602a958 ACPI / PM: Allow device power states to be used for CONFIG_PM unset
Currently, drivers/acpi/device_pm.c depends on CONFIG_PM and all of
the functions defined in there are replaced with static inline stubs
if that option is unset.  However, CONFIG_PM means, roughly, "runtime
PM or suspend/hibernation support" and some of those functions are
useful regardless of that.  For example, they are used by the ACPI
fan driver for controlling fans and acpi_device_set_power() is called
during device removal.  Moreover, device initialization may depend on
setting device power states properly.

For these reasons, make the routines manipulating ACPI device power
states defined in drivers/acpi/device_pm.c available for CONFIG_PM
unset too.

Reported-by: Zhang Rui <rui.zhang@intel.com>
Reported-and-tested-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.9+ <stable@vger.kernel.org>
2013-05-22 00:19:28 +02:00
Rafael J. Wysocki 75eb2d13ac ACPI / PM: Fix potential problem in acpi_device_get_power()
Theoretically, in some situations acpi_device_get_power() may return
an incorrect result, because the settings of the power resources
depended on by the device may indicate a power state shallower than
the actual power state of the device.

Say that two devices, A and B, depend on two power resources, X and
Y, in such a way that _PR0 for both A and B list both X and Y and
_PR3 for both A and B list power resource Y alone.  Also suppose
that _PS0 and _PS3 are present for both A and B.  Then, if devices
A and B are initially in D0, power resources X and Y are initially
"on" and their reference counters are equal to 2.  To put device A
into power state D3hot the kernel will decrement the reference
counter of power resource X, but that power resource won't be turned
off, because it is still in use by device B (its reference counter is
equal to 1).  Next, _PS3 will be executed for device A.  Afterward
the configuration of the power resources will indicate that device
A is in power state D0 (both X and Y are "on"), but in fact it is
in D3hot (because _PS3 has been executed for it).

In that situation, if acpi_device_get_power() is called to get the
power state of device A, it will first execute _PSC for it which
should return 3.  That will cause acpi_device_get_power() to run
acpi_power_get_inferred_state() for device A and the resultant power
state will be D0, which is incorrect.

To fix that change acpi_device_get_power() to first execute
acpi_power_get_inferred_state() for the given device (if it
depends on power resources) and to evaluate _PSC for it subsequently,
so that the result inferred from the power resources configuration
can be amended by the _PSC return value.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
2013-03-25 15:49:44 +01:00
Rafael J. Wysocki 511d5c4212 ACPI / PM: Handle missing _PSC in acpi_bus_update_power()
If _PS0 is defined for an ACPI device node, but _PSC isn't and
the device node doesn't use power resources for power management,
acpi_bus_update_power() will fail to update the power state of it,
because acpi_device_get_power() returns ACPI_STATE_UNKNOWN in that
case.

To handle that situation make acpi_bus_update_power() follow
acpi_bus_init_power() and try to force the given device node into
power state D0.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-03 14:57:32 +01:00
Rafael J. Wysocki b378549226 ACPI / PM: Do not power manage devices in unknown initial states
In general, for ACPI device power management to work, the initial
power states of devices must be known (otherwise, we wouldn't be able
to keep track of power resources, for example).  Hence, if it is
impossible to determine the initial ACPI power states of some
devices, they can't be regarded as power-manageable using ACPI.

For this reason, modify acpi_bus_get_power_flags() to clear the
power_manageable flag if acpi_bus_init_power() fails and add some
extra fallback code to acpi_bus_init_power() to cover broken
BIOSes that provide _PS0/_PS3 without _PSC for some devices.

Verified to work on my HP nx6325 that has this problem.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Peter Wu <lekensteyn@gmail.com>
2013-02-01 23:43:02 +01:00
Yasuaki Ishimatsu dde3bb4159 ACPI / PM: Fix acpi_bus_get_device() check in drivers/acpi/device_pm.c
acpi_bus_get_device() returns int not acpi_status.

The patch change not to apply ACPI_FAILURE() to the return value of
acpi_bus_get_device().

Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-31 21:03:46 +01:00
Rafael J. Wysocki e5656271b0 ACPI / PM: Fix device power state value after transitions to D3cold
When a transition to the D3cold power state is requested,
acpi_device_set_power() first carries out a transition to D3hot and
then turns off the device's power resources.  However, it fails to
update the device's power.state field appropriately and D3hot is
stored in it as a result.

Fix this, but make sure that the device's power state will be
D3hot if its power resources cannot be turned off in the final
step.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-22 12:56:35 +01:00
Rafael J. Wysocki 898fee4f6e ACPI / PM: Use string "D3cold" to represent ACPI_STATE_D3_COLD
Make acpi_power_state_string() return "D3cold" as the string
representation of ACPI power state D3cold instead of "D3" returned
currently, which is confusing.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-22 12:56:26 +01:00
Rafael J. Wysocki e78adb7595 ACPI / PM: Always evaluate _PSn after setting power resources
The ACPI specitication (ACPI 5, Sections 7.2.8 - 7.2.11) requires
that the _PSn (n = 0..3) method, if present, be executed after the
power resources for the given device power state have been set
appropriately.  However, acpi_device_set_power() does that only
if the new power state is going to be higher-power (lower-number)
than the power state the device is in already.  Otherwise, the
ordering is reverse to protect against situations in which _PSn
might access device registers unavailable after configuring the
power resources for power state Dn (D3 meaning D3hot).

Such situations are very unlikely to happen, though, and _PSn may
actually be implemented with the assumption that power resources
have been configured for power state Dn in advance, so change the
code to follow the specification literally.

This change was previously porposed in a different form by Lv Zheng.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-22 12:56:04 +01:00
Rafael J. Wysocki 9c0f45e388 ACPI / PM: Introduce helper for executing _PSn methods
To reduce code duplication between acpi_device_set_power() and
acpi_bus_init_power(), introduce a new helper function for executing
ACPI devices' _PSn (n = 0..3) methods, acpi_dev_pm_explicit_set().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-22 12:55:52 +01:00
Rafael J. Wysocki a2367807b8 ACPI / PM: Make acpi_bus_init_power() more robust
The ACPI specification requires the _PSC method to be present under
a device object if its power state cannot be inferred from the states
of power resources used by it (ACPI 5, Section 7.6.2).  However, it
also requires that (for power states D0-D2 and D3hot) if the _PSn
(n = 0, 1, 2, 3) method is present under the device object, it also
must be executed after the power resources have been set
appropriately for the device to go into power state Dn (D3 means
D3hot in this case).  Thus it is not clear from the specification
whether or not the _PSn method should be executed if the initial
configuraion of power resources used by the device indicates power
state Dn and the _PSC method is not present.

The current implementation of acpi_bus_init_power() is based on the
assumption that it should not be necessary to execute _PSn in the
above situation, but experience shows that in fact that assumption
need not be satisfied.  For this reason, make acpi_bus_init_power()
always execute _PSn if the initial configuration of device power
resources indicates power state Dn.

Reported-and-tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-22 12:54:38 +01:00
Mika Westerberg 4d56410b95 ACPI / PM: remove leading whitespace from #ifdef
It is there probably due to an accident, get rid of it so that the format
is consistent across the file.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-19 22:09:23 +01:00
Rafael J. Wysocki 9ce4e60711 ACPI / PM: Move device power management functions to device_pm.c
Move ACPI device power management functions from drivers/acpi/bus.c
to drivers/acpi/device_pm.c.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-19 22:09:22 +01:00
Rafael J. Wysocki bc9b6407bd ACPI / PM: Rework the handling of devices depending on power resources
Commit 0090def6 (ACPI: Add interface to register/unregister device
to/from power resources) made it possible to indicate to the ACPI
core that if the given device depends on any power resources, then
it should be resumed as soon as all of the power resources required
by it to transition to the D0 power state have been turned on.

Unfortunately, however, this was a mistake, because all devices
depending on power resources should be treated this way (i.e. they
should be resumed when all power resources required by their D0
state have been turned on) and for the majority of those devices
the ACPI core can figure out by itself which (physical) devices
depend on what power resources.

For this reason, replace the code added by commit 0090def6 with a
new, much more straightforward, mechanism that will be used
internally by the ACPI core and remove all references to that code
from kernel subsystems using ACPI.

For the cases when there are (physical) devices that should be
resumed whenever a not directly related ACPI device node goes into
D0 as a result of power resources configuration changes, like in
the SATA case, add two new routines, acpi_dev_pm_add_dependent()
and acpi_dev_pm_remove_dependent(), allowing subsystems to manage
such dependencies.  Convert the SATA subsystem to use the new
functions accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-17 14:11:05 +01:00
Rafael J. Wysocki 6a8dd80821 Merge branch 'acpi-scan' into acpi-pm
The following commits depend on the 'acpi-scan' material.
2013-01-17 14:10:27 +01:00
Rafael J. Wysocki 5cc36c724e ACPI / PM: Do not apply ACPI_SUCCESS() to acpi_bus_get_device() result
Since the return value of acpi_bus_get_device() is not of type
acpi_status, ACPI_SUCCESS() should not be used for checking its
return value.  Fix that.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-01-03 13:10:21 +01:00
Rafael J. Wysocki d2e5f0c16a ACPI / PCI: Rework the setup and cleanup of device wakeup
Currently, the ACPI wakeup capability of PCI devices is set up
in two different places, partially in acpi_pci_bind() where
runtime wakeup is initialized and partially in
platform_pci_wakeup_init(), where system wakeup is initialized.
The cleanup is only done in acpi_pci_unbind() and it only covers
runtime wakeup.

Use the new .setup() and .cleanup() callbacks in struct acpi_bus_type
to consolidate that code and do the setup and the cleanup each in one
place.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-01-03 13:09:41 +01:00
Rafael J. Wysocki b88ce2a415 ACPI / PM: Allow attach/detach routines to change device power states
Make it possible to ask the routines used for adding/removing devices
to/from the general ACPI PM domain, acpi_dev_pm_attach() and
acpi_dev_pm_detach(), respectively, to change the power states of
devices so that they are put into the full-power state automatically
by acpi_dev_pm_attach() and into the lowest-power state available
automatically by acpi_dev_pm_detach().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2012-11-26 10:03:06 +01:00
Rafael J. Wysocki e5cc8ef312 ACPI / PM: Provide ACPI PM callback routines for subsystems
Some bus types don't support power management natively, but generally
there may be device nodes in ACPI tables corresponding to the devices
whose bus types they are (under ACPI 5 those bus types may be SPI,
I2C and platform).  If that is the case, standard ACPI power
management may be applied to those devices, although currently the
kernel has no means for that.

For this reason, provide a set of routines that may be used as power
management callbacks for such devices.  This may be done in three
different ways.

 (1) Device drivers handling the devices in question may run
     acpi_dev_pm_attach() in their .probe() routines, which (on
     success) will cause the devices to be added to the general ACPI
     PM domain and ACPI power management will be used for them going
     forward.  Then, acpi_dev_pm_detach() may be used to remove the
     devices from the general ACPI PM domain if ACPI power management
     is not necessary for them any more.

 (2) The devices' subsystems may use acpi_subsys_runtime_suspend(),
     acpi_subsys_runtime_resume(), acpi_subsys_prepare(),
     acpi_subsys_suspend_late(), acpi_subsys_resume_early() as their
     power management callbacks in the same way as the general ACPI
     PM domain does that.

 (3) The devices' drivers may execute acpi_dev_suspend_late(),
     acpi_dev_resume_early(), acpi_dev_runtime_suspend(),
     acpi_dev_runtime_resume() from their power management callbacks
     as appropriate, if that's absolutely necessary, but it is not
     recommended to do that, because such drivers may not work
     without ACPI support as a result.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15 00:15:18 +01:00
Rafael J. Wysocki a6ae7594b1 ACPI / PM: Move device PM functions related to sleep states
Introduce helper function returning the target sleep state of the
system and use it to move the remaining device power management
functions from sleep.c to device_pm.c.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15 00:15:18 +01:00
Rafael J. Wysocki dee8370cc8 ACPI / PM: Split device wakeup management routines
Two device wakeup management routines in device_pm.c and sleep.c,
acpi_pm_device_run_wake() and acpi_pm_device_sleep_wake(), take a
device pointer argument and use it to obtain the ACPI handle of the
corresponding ACPI namespace node.  That handle is then used to get
the address of the struct acpi_device object corresponding to the
struct device passed as the argument.

Unfortunately, that last operation may be costly, because it involves
taking the global ACPI namespace mutex, so it shouldn't be carried
out too often.  However, the callers of those routines usually call
them in a row with acpi_pm_device_sleep_state() which also takes that
mutex for the same reason, so it would be more efficient if they ran
acpi_bus_get_device() themselves to obtain a pointer to the struct
acpi_device object in question and then passed that pointer to the
appropriate PM routines.

To make that possible, split each of the PM routines mentioned above
in two parts, one taking a struct acpi_device pointer argument and
the other implementing the current interface for compatibility.

Additionally, change acpi_pm_device_run_wake() to actually return
an error code if there is an error while setting up runtime remote
wakeup for the device.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15 00:15:17 +01:00
Rafael J. Wysocki cd7bd02d31 ACPI / PM: Move runtime remote wakeup setup routine to device_pm.c
The ACPI function for setting up devices to do runtime remote
wakeup is now located in drivers/acpi/sleep.c, but
drivers/acpi/device_pm.c is a more logical place for it, so move it
there.

No functional changes should result from this modification.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15 00:15:17 +01:00
Rafael J. Wysocki 86b3832c64 ACPI / PM: Move device power state selection routine to device_pm.c
The ACPI function for choosing device power state is now located
in drivers/acpi/sleep.c, but drivers/acpi/device_pm.c is a more
logical place for it, so move it there.

However, instead of moving the function entirely, move its core only
under a different name and with a different list of arguments, so
that it is more flexible, and leave a wrapper around it in the
original location.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15 00:15:16 +01:00
Rafael J. Wysocki ec2cd81ccf ACPI / PM: Move routines for adding/removing device wakeup notifiers
ACPI routines for adding and removing device wakeup notifiers are
currently defined in a PCI-specific file, but they will be necessary
for non-PCI devices too, so move them to a separate file under
drivers/acpi and rename them to indicate their ACPI origins.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15 00:15:16 +01:00