linux-stable.git/drivers/acpi/device_pm.c, branch linux-3.16.y

ACPI: PM: Avoid attaching ACPI PM domain to certain devices

2020-04-28T18:02:45+00:00

commit b9ea0bae260f6aae546db224daa6ac1bd9d94b91 upstream.

Certain ACPI-enumerated devices represented as platform devices in
Linux, like fans, require special low-level power management handling
implemented by their drivers that is not in agreement with the ACPI
PM domain behavior.  That leads to problems with managing ACPI fans
during system-wide suspend and resume.

For this reason, make acpi_dev_pm_attach() skip the affected devices
by adding a list of device IDs to avoid to it and putting the IDs of
the affected devices into that list.

Fixes: e5cc8ef31267 (ACPI / PM: Provide ACPI PM callback routines for subsystems)
Reported-by: Zhang Rui 
Tested-by: Todd Brandt 
Signed-off-by: Rafael J. Wysocki 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

ACPI / PM: Add missing pm_generic_complete() invocation

2015-07-15T09:00:25+00:00

commit 3d56402d3fa8d10749eeb36293dd1992bd5ad0c3 upstream.

Add missing invocation of pm_generic_complete() to
acpi_subsys_complete() to allow ->complete callbacks provided
by the drivers of devices using the ACPI PM domain to be executed
during system resume.

Fixes: f25c0ae2b4c4 (ACPI / PM: Avoid resuming devices in ACPI PM domain during system suspend)
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Luis Henriques

ACPI / PM: Fix PM initialization for devices that are not present

2015-01-16T14:34:26+00:00

commit 1b1f3e1699a9886f1070f94171097ab4ccdbfc95 upstream.

If an ACPI device object whose _STA returns 0 (not present and not
functional) has _PR0 or _PS0, its power_manageable flag will be set
and acpi_bus_init_power() will return 0 for it.  Consequently, if
such a device object is passed to the ACPI device PM functions, they
will attempt to carry out the requested operation on the device,
although they should not do that for devices that are not present.

To fix that problem make acpi_bus_init_power() return an error code
for devices that are not present which will cause power_manageable to
be cleared for them as appropriate in acpi_bus_get_power_flags().
However, the lists of power resources should not be freed for the
device in that case, so modify acpi_bus_get_power_flags() to keep
those lists even if acpi_bus_init_power() returns an error.
Accordingly, when deciding whether or not the lists of power
resources need to be freed, acpi_free_power_resources_lists()
should check the power.flags.power_resources flag instead of
flags.power_manageable, so make that change too.

Furthermore, if acpi_bus_attach() sees that flags.initialized is
unset for the given device, it should reset the power management
settings of the device and re-initialize them from scratch instead
of relying on the previous settings (the device may have appeared
after being not present previously, for example), so make it use
the 'valid' flag of the D0 power state as the initial value of
flags.power_manageable for it and call acpi_bus_init_power() to
discover its current power state.

Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Mika Westerberg 
Signed-off-by: Luis Henriques

ACPI / PM: Ignore wakeup setting if the ACPI companion can't wake up

2014-12-01T10:26:07+00:00

commit 78579b7c7eb45f0e7ec5e9437087ed21749f9a9c upstream.

As reported by Dmitry, on some Chromebooks there are devices with
corresponding ACPI objects and with unusual system wakeup
configuration.  Namely, they technically are wakeup-capable, but the
wakeup is handled via a platform-specific out-of-band mechanism and
the ACPI PM layer has no information on the wakeup capability.  As
a result, device_may_wakeup(dev) called from acpi_dev_suspend_late()
returns 'true' for those devices, but the wakeup.flags.valid flag is
unset for the corresponding ACPI device objects, so acpi_device_wakeup()
reproducibly fails for them causing acpi_dev_suspend_late() to return
an error code.  The entire system suspend is then aborted and the
machines in question cannot suspend at all.

Address the problem by ignoring the device_may_wakeup(dev) return
value in acpi_dev_suspend_late() if the ACPI companion of the device
being handled has wakeup.flags.valid unset (in which case it is clear
that the wakeup is supposed to be handled by other means).

This fixes a regression introduced by commit a76e9bd89ae7 (i2c:
attach/detach I2C client device to the ACPI power domain) as the
affected systems could suspend and resume successfully before that
commit.

Fixes: a76e9bd89ae7 (i2c: attach/detach I2C client device to the ACPI power domain)
Reported-by: Dmitry Torokhov 
Reviewed-by: Dmitry Torokhov 
Signed-off-by: Rafael J. Wysocki 
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques

ACPI / PM: Export rest of the subsys PM callbacks

2014-05-20T11:23:07+00:00

No reason for excluding the remaining ones.

Signed-off-by: Heikki Krogerus 
[rjw: Rebased and exported the new acpi_subsys_complete() too.]
Signed-off-by: Rafael J. Wysocki

ACPI / PM: Avoid resuming devices in ACPI PM domain during system suspend

2014-05-20T11:22:48+00:00

Rework the ACPI PM domain's PM callbacks to avoid resuming devices
during system suspend (in order to modify their wakeup settings etc.)
if that isn't necessary.

Signed-off-by: Rafael J. Wysocki

ACPI / PM: Resume runtime-suspended devices later during system suspend

2014-03-03T23:17:48+00:00

Runtime-suspended devices are resumed during system suspend by
acpi_subsys_prepare() for two reasons: First, because they may need
to be reprogrammed in order to change their wakeup settings and,
second, because they may need to be operatonal for their children
to be successfully suspended.  That is a problem, though, if there
are many runtime-suspended devices that need to be resumed this
way during system suspend, because the .prepare() PM callbacks of
devices are executed sequentially and the times taken by them
accumulate, which may increase the total system suspend time quite
a bit.

For this reason, move the resume of runtime-suspended devices up
to the next phase of device suspend (during system suspend), except
for the ones that have power.ignore_children set.  The exception is
made, because the devices with power.ignore_children set may still
be necessary for their children to be successfully suspended (during
system suspend) and they won't be resumed automatically as a result
of the runtime resume of their children.

Signed-off-by: Rafael J. Wysocki

Merge branches 'acpi-processor', 'acpi-hotplug', 'acpi-init', 'acpi-pm' and 'acpica'

2014-01-29T10:47:18+00:00

* acpi-processor:
  ACPI / scan: reduce log level of "ACPI: \_PR_.CPU4: failed to get CPU APIC ID"
  ACPI / processor: Return specific error value when mapping lapic id

* acpi-hotplug:
  ACPI / scan: Clear match_driver flag in acpi_bus_trim()

* acpi-init:
  ACPI / init: Flag use of ACPI and ACPI idioms for power supplies to regulator API

* acpi-pm:
  ACPI / PM: Use ACPI_COMPANION() to get ACPI companions of devices

* acpica:
  ACPICA: Remove bool usage from ACPICA.

ACPI / PM: Use ACPI_COMPANION() to get ACPI companions of devices

2014-01-27T22:10:24+00:00

The ACPI device PM code in device_pm.c uses a special function,
acpi_dev_pm_get_node(), to obtain an ACPI companion object of a given
device.  However, that is not necessary any more after recent changes
that introduced the ACPI_COMPANION() macro serving exactly the same
purpose, but working in a much more straightforward way.  For this
reason, drop acpi_dev_pm_get_node() and use ACPI_COMPANION() instead
of it everywhere.

Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Mika Westerberg

ACPI / scan: Add acpi_device objects for all device nodes in the namespace

2013-11-22T20:54:37+00:00

Modify the ACPI namespace scanning code to register a struct
acpi_device object for every namespace node representing a device,
processor and so on, even if the device represented by that namespace
node is reported to be not present and not functional by _STA.

There are multiple reasons to do that.  First of all, it avoids
quite a lot of overhead when struct acpi_device objects are
deleted every time acpi_bus_trim() is run and then added again
by a subsequent acpi_bus_scan() for the same scope, although the
namespace objects they correspond to stay in memory all the time
(which always is the case on a vast majority of systems).

Second, it will allow user space to see that there are namespace
nodes representing devices that are not present at the moment and may
be added to the system.  It will also allow user space to evaluate
_SUN for those nodes to check what physical slots the "missing"
devices may be put into and it will make sense to add a sysfs
attribute for _STA evaluation after this change (that will be
useful for thermal management on some systems).

Next, it will help to consolidate the ACPI hotplug handling among
subsystems by making it possible to store hotplug-related information
in struct acpi_device objects in a standard common way.

Finally, it will help to avoid a race condition related to the
deletion of ACPI namespace nodes.  Namely, namespace nodes may be
deleted as a result of a table unload triggered by _EJ0 or _DCK.
If a hotplug notification for one of those nodes is triggered
right before the deletion and it executes a hotplug callback
via acpi_hotplug_execute(), the ACPI handle passed to that
callback may be stale when the callback actually runs.  One way
to work around that is to always pass struct acpi_device pointers
to hotplug callbacks after doing a get_device() on the objects in
question which eliminates the use-after-free possibility (the ACPI
handles in those objects are invalidated by acpi_scan_drop_device(),
so they will trigger ACPICA errors on attempts to use them).

Signed-off-by: Rafael J. Wysocki 
Tested-by: Mika Westerberg