This is a backport of mainline commit
1e78a0c7fc92aee076965d516cf54475c39e9894.

The TMU device on the Mackerel board belongs to the A4R power domain
and loses power when the domain is turned off.  Unfortunately, the
TMU driver is not prepared to cope with such situations and crashes
the system when that happens.  To work around this problem introduce
a new helper function, pm_genpd_dev_always_on(), allowing a device
driver to mark its device as "always on" in case it belongs to a PM
domain, which will make the generic PM domains core code avoid
powering off the domain containing the device, both at run time and
during system suspend.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Simon Horman <horms@verge.net.au>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This is a backport of mainline commit
18dd2ece3cde14cfd42e95a89eb14016699a5f15.

Power domains that were off before hibernation shouldn't be turned on
during device restore, so prevent that from happening.

This change fixed up mainline commit
65533bbf63b4f37723fdfedc73d0653958973323

    PM / Domains: Fix hibernation restore of devices, v2

that didn't include it by mistake.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This is a backport of mainline commit
65533bbf63b4f37723fdfedc73d0653958973323.

During resume from hibernation pm_genpd_restore_noirq() should only
power off domains whose suspend_power_off flags are set once and
not every time it is called for a device in the given domain.
Moreover, it shouldn't decrement genpd->suspended_count, because
that field is not touched during device freezing and therefore it is
always equal to 0 when pm_genpd_restore_noirq() runs for the first
device in the given domain.

This means pm_genpd_restore_noirq() may use genpd->suspended_count
to determine whether or not it it has been called for the domain in
question already in this cycle (it only needs to increment that
field every time it runs for this purpose) and whether or not it
should check if the domain needs to be powered off.  For that to
work, though, pm_genpd_prepare() has to clear genpd->suspended_count
when it runs for the first device in the given domain (in which case
that flag need not be cleared during domain initialization).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit cc85b20780562d404e18a47b9b55b4a5102ae53e upstream.

During system suspend pm_genpd_suspend_noirq() checks if the given
device is in a wakeup path (i.e. it appears to be needed for one or
more wakeup devices to work or is a wakeup device itself) and if it
needs to be "active" for wakeup to work.  If that is the case, the
function returns 0 without incrementing the device domain's counter
of suspended devices and without executing genpd_stop_dev() for the
device.  In consequence, the device is not stopped (e.g. its clock
isn't disabled) and power is always supplied to its domain in the
resulting system sleep state.

However, pm_genpd_resume_noirq() doesn't repeat that check and it
runs genpd_start_dev() and decrements the domain's counter of
suspended devices even for the wakeup device that weren't stopped by
pm_genpd_suspend_noirq().  As a result, the start callback may be run
unnecessarily for them and their domains' counters of suspended
devices may become negative.  Both outcomes aren't desirable, so fix
pm_genpd_resume_noirq() to look for wakeup devices that might not be
stopped by during system suspend.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Some callback functions defined in drivers/base/power/domain.c are
only necessary if CONFIG_PM_SLEEP is set and they call some other
functions that are only available in that case.  For this reason,
they should not be compiled at all when CONFIG_PM_SLEEP is not set.

Reported-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Commit d23b9b00cdde5c93b914a172cecd57d5625fcd04 (PM / Domains: Rework
system suspend callback routines (v2)) broke the system suspend and
resume handling by devices belonging to generic PM domains, because
it used freeze/thaw callbacks instead of suspend/resume ones and
didn't initialize device callbacks for system suspend/resume
properly at all.  Fix those problems.

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

Add a name member pointer to struct generic_pm_domain and use it in
diagnostic messages regarding the domain power-off and power-on
latencies.  Update the ARM shmobile SH7372 code to assign names to
the PM domains used by it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Measure the time of execution of the .stop(), .start(), .save_state()
and .restore_state() PM domain device callbacks and if the result
is greater than the corresponding latency value stored in the
device's struct generic_pm_domain_data object, replace the inaccurate
value with the measured time.

Do analogously for the PM domains' .power_off() and .power_off()
callbacks.

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

Add a function deciding whether or not a given PM domain should
be powered off on the basis of the PM QoS constraints of devices
belonging to it and their PM QoS timing data.

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

Add a function deciding whether or not devices should be stopped in
pm_genpd_runtime_suspend() depending on their PM QoS constraints
and stop/start timing values.  Make it possible to add information
used by this function to device objects.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>