drivers: base: power: add proper SPDX identifiers on files that did not have them.

There were a few files in the driver core power code that did not have
SPDX identifiers on them, so fix that up. At the same time, remove the
"free form" text that specified the license of the file, as that is
impossible for any tool to properly parse.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

PM / sleep: Remove pm_complete_with_resume_check()

According to recent changes for ACPI, the are longer any users of
pm_complete_with_resume_check(), thus let's drop it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / PCI / ACPI: Kick devices that might have been reset by firmware

There is a concern that if the platform firmware was involved in
the system resume that's being completed, some devices might have
been reset by it and if those devices had the power.direct_complete
flag set during the preceding suspend transition, they may stay
in a reset-power-on state indefinitely (until they are runtime-resumed
and then suspended again). That may not be a big deal from the
individual device's perspective, but if the system is an SoC, it may
be prevented from entering deep SoC-wide low-power states on idle
because of that.

The devices that are most likely to be affected by this issue are
PCI devices and ACPI-enumerated devices using the general ACPI PM
domain, so to prevent it from happening for those devices, force a
runtime resume for them if they have their power.direct_complete
flags set and the platform firmware was involved in the resume
transition currently in progress.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / sleep: Drop pm_request_idle() from pm_generic_complete()

The pm_request_idle() in pm_generic_complete() is pointless as it is
called with the runtime PM usage counter different from zero (bumped
up by the core during the prepare phase of system suspend) and the
core calls pm_runtime_put() for all devices after executing their
complete callbacks, so drop it.

This allows the PCI PM layer to use pm_generic_complete() too.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>

PM / Runtime: Spelling s/competing/completing/

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / Runtime: Implement the pm_generic_runtime functions for CONFIG_PM

The pm_generic_runtime_suspend|resume functions were implemented within
CONFIG_PM_RUNTIME.

As we also may use runtime PM callbacks during system suspend, to put
devices into low power state, we need to move the implementation of
pm_generic_runtime_suspend|resume to CONFIG_PM.

This change gives a power domain provision to invoke a platform
driver's runtime PM callback from a power domain's system PM callback.
This were earlier prevented by the platform bus, since it uses the
pm_generic_runtime_suspend|resume functions as runtime PM callbacks.

Cc: Kevin Hilman <khilman@linaro.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / Runtime: Rework the "runtime idle" helper routine

The "runtime idle" helper routine, rpm_idle(), currently ignores
return values from .runtime_idle() callbacks executed by it.
However, it turns out that many subsystems use
pm_generic_runtime_idle() which checks the return value of the
driver's callback and executes pm_runtime_suspend() for the device
unless that value is not 0. If that logic is moved to rpm_idle()
instead, pm_generic_runtime_idle() can be dropped and its users
will not need any .runtime_idle() callbacks any more.

Moreover, the PCI, SCSI, and SATA subsystems' .runtime_idle()
routines, pci_pm_runtime_idle(), scsi_runtime_idle(), and
ata_port_runtime_idle(), respectively, as well as a few drivers'
ones may be simplified if rpm_idle() calls rpm_suspend() after 0 has
been returned by the .runtime_idle() callback executed by it.

To reduce overall code bloat, make the changes described above.

Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>

PM / Runtime: Asyncronous idle|suspend devices at system resume

Use the asyncronous runtime PM API when returning the runtime
reference for the device after the system resume is completed.

By using the asyncronous runtime PM API we don't have to wait
for each an every device to become idle|suspended. Instead we
can move on and handle the next device in queue.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / Sleep: Introduce generic callbacks for new device PM phases

Introduce generic subsystem callbacks for the new phases of device
suspend/resume during system power transitions: "late suspend",
"early resume", "late freeze", "early thaw", "late poweroff",
"early restore".

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

PM: Drop generic_subsys_pm_ops

Since the PM core is now going to execute driver callbacks directly
if the corresponding subsystem callbacks are not present,
forward-only subsystem callbacks (i.e. such that only execute the
corresponding driver callbacks) are not necessary any more. Thus
it is possible to remove generic_subsys_pm_ops, because the only
callback in there that is not forward-only, .runtime_idle, is not
really used by the only user of generic_subsys_pm_ops, which is
vio_bus_type.

However, the generic callback routines themselves cannot be removed
from generic_ops.c, because they are used individually by a number
of subsystems.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

PM / Sleep: Merge internal functions in generic_ops.c

After the change that removed the code related to runtime PM
from __pm_generic_call() and __pm_generic_resume() these two
functions need not be separate any more, so merge them.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

PM / Sleep: Simplify generic system suspend callbacks

The pm_runtime_suspended() check in __pm_generic_call() doesn't
really help and may cause problems to happen, because in some cases
the system suspend callbacks need to be called even if the given
device has been suspended by runtime PM. For example, if the device
generally supports remote wakeup and is not enabled to wake up
the system from sleep, it should be prevented from generating wakeup
signals during system suspend and that has to be done by the
suspend callbacks that the pm_runtime_suspended() check prevents from
being executed.

Similarly, it may not be a good idea to unconditionally change
the runtime PM status of the device to 'active' in
__pm_generic_resume(), because the driver may want to leave the
device in the 'suspended' state, depending on what happened to it
before the system suspend and whether or not it is enabled to
wake up the system.

For the above reasons, remove the pm_runtime_suspended()
check from __pm_generic_call() and remove the code changing the
device's runtime PM status from __pm_generic_resume().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

drivers/base: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required.

Most of these files were implicitly getting EXPORT_SYMBOL via
device.h which was including module.h, but that path will be broken
soon.

[ with input from Stephen Rothwell <sfr@canb.auug.org.au> ]

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

PM: Introduce generic "noirq" callback routines for subsystems (v2)

Introduce generic "noirq" power management callback routines for
subsystems in addition to the "regular" generic PM callback routines.

The new routines will be used, among other things, for implementing
system-wide PM transitions support for generic PM domains.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

PM: Introduce generic prepare and complete callbacks for subsystems

Introduce generic .prepare() and .complete() power management
callbacks, currently missing, that can be used by subsystems and
power domains and export them. Provide NULL definitions of all
the generic system sleep callbacks for CONFIG_PM_SLEEP unset.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

PM / Runtime: Generic resume shouldn't set RPM_ACTIVE unconditionally

The __pm_generic_resume() function changes the given device's runtime
PM status to RPM_ACTIVE if its driver's callback returns 0, but it
only should do that if the rumtime PM is enabled for the device.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

PM / Runtime: Fix comments to match runtime callback code

Commit 05aa55dddb9ee4045c320661068bea78dad6a6e5 changed routines to
succeed if the driver handler is not defined. Comments were not updated.

Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

PM / Runtime: Lenient generic runtime pm callbacks

Allow drivers, that belong to subsystems which use the generic
runtime pm callbacks, not to define runtime pm suspend/resume handlers,
by implicitly assuming success in such cases.

This is needed to eliminate nop handlers that would otherwise be
necessary by drivers which enable runtime pm, but don't need
to do anything when their devices are runtime-suspended/resumed.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

PM: Provide generic subsystem-level callbacks

There are subsystems whose power management callbacks only need to
invoke the callbacks provided by device drivers. Still, their system
sleep PM callbacks should play well with the runtime PM callbacks,
so that devices suspended at run time can be left in that state for
a system sleep transition.

Provide a set of generic PM callbacks for such subsystems and
define convenience macros for populating dev_pm_ops structures.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>