The sh7372 cpuidle code uses the same artificially designed routine
shmobile_cpuidle_enter() as the .enter() callback for all of its
cpuidle states.  However, shmobile_cpuidle_enter() calls a different
"enter" function for each state using an array of function pointers
populated by the sh7372 PM initialization code.  Moreover, the
states[] array of the shmobile cpuidle driver is populated by that
code as well, although in principle it just might have been filled
with static data.

All of that complexity goes away if the sh7372 cpuidle code is
allowed to define its own cpuidle driver structure that can be passed
for registration to the common shmobile cpuidle initialization
routine, so modify the code accordingly.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

The role of the only function in the common.c file in
arch/arm/mach-shmobile, shmobile_init_late(), is to call two
initializers whose definitions depend on kernel configuration
options.  Those initializers may very well be called from a static
inline function in arm/mach-shmobile/include/mach/common.h,
though, in which makes the code a bit easier to read.  Moreover,
the common.c may be dropped entirely then.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

The !console_suspend_enabled check in sh7372_enter_suspend() seems
to be reversed and the condition it is supposed to catch (console
clock enabled) should be detected by the sh7372_sysc_valid() check
anyway, so remove it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Use the function rmobile_add_devices_to_domains() introduced
previously for adding devices to PM domains during the AP4EVB
initialization instead of a series of rmobile_add_device_to_domain*()
calls.  This also causes the default device PM QoS latencies to be
used on that board in analogy with Mackerel.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

On SH7372 and Mackerel devices are added to PM domains through a
series of rmobile_add_device_to_domain_td() calls where the last
argument is always the same.  This is quite inefficient, so add
a common function for adding devices to PM domains that reads the
domain-device pairs information from a table and use it during SH7372
and Mackerel initialization.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

The results of adaptive latency computations in
GENPD_DEV_TIMED_CALLBACK() show that the start/stop and save/restore
state latencies of all devices on the Mackerel board I have tried are
a little below 250 us.  Therefore, if the 250 us is used as the
common initial value of the latency fields in struct gpd_timing_data
for all devices on Mackerel, the latency values will never have to
change at run time and there won't be any overhead related to
re-computation of the corresponding PM QoS data.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

The results of adaptive latency computations in
GENPD_DEV_TIMED_CALLBACK() show that the start/stop and save/restore
state latencies of all devices on SH7372 I have tried are a little
below 250 us.  Therefore, if the 250 us is used as the common initial
value of the latency fields in struct gpd_timing_data for all devices
on SH7372, the latency values will never have to change at run time
and there won't be any overhead related to re-computation of the
corresponding PM QoS data.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Make it possible to specify device start/stop and save/restore
state latencies directy when adding devices to PM domains.  For
this purpose, introduce rmobile_add_device_to_domain_td() whose
third argument is a pointer to a struct gpd_timing_data object
containing device latency data.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

The results of adaptive latency computations in __pm_genpd_poweron()
and pm_genpd_poweroff() show that the power on/power off latencies
of all power domains in SH7372 are a little below 250 us.  Therefore,
if 250 us is used as the common initial value of the latency fields
in struct generic_pm_domain for all domains, the latency values
will never have to change at run time and there won't be any overhead
related to re-computation of the corresponding PM QoS data.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Since rmobile_init_pm_domain() is not called anywhere outside of
arch/arm/mach-shmobile/pm-rmobile.c any more, it can be made static
and its header may be removed from pm-rmobile.h.  Modify the code
accordingly.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Instead of giving a name to every r8a7779's PM domain object, put
them all into a table and initialize them all together in a loop.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Instead of giving a name to every r8a7740's PM domain object, put
them all into a table and use rmobile_init_domains(), introduced by a
previous patch, for initializing them all altogether.  Also, use
pm_genpd_add_subdomain_names() for adding A3SP as a subdomain of A4S.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Instead of giving a name to every sh7372's PM domain object, put them
all into a table and use rmobile_init_domains(), introduced by a
previous patch, for initializing them all altogether.  Also, use
pm_genpd_add_subdomain_names() for adding subdomains to the PM
domains and pm_genpd_poweron_name() for turning on the A4S domain
when preparing for system suspend.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

The sh7372_enter_suspend() routine checks the status field of the
generic PM domain object corresponding to the A4S domain in order to
check if it can turn that domain off when entering system sleep.
However, it shouldn't rely on the specific values of the generic
data structures this way, so make it use its own mechanism to
recognize when it is safe to turn that domain off.

For this purpos, introduce a boolean variable a4s_suspend_ready
that will be set by the A4S' suspend routine and unset by its
resume routine executed by rmobile_pd_power_down() and
__rmobile_pd_power_up(), respectively.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Add a new routine, rmobile_init_domains(), allowing the caller
to initialize all generic PM objects stored in a table in one
operation.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Make the power management code under arch/arm/mach-shmobile/
use pm_genpd_add_subdomain_names() for adding subdomains to power
domains, which makes it possible to drop
rmobile_pm_add_subdomain() and will allow us to carry out those
operations for domain objects stored in tables in a straightforward
way.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

If the r8a7779's PM domains are given names, this SoC and its boards
will be able to use rmobile_add_device_to_domain() for adding devices
to those domains and r8a7779_add_device_to_domain(), which is not
used anywhere at the moment anyway, may be dopped.

Accordingly, give names to the r8a7779's PM domains and drop
r8a7779_add_device_to_domain().
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Make the power management code under arch/arm/mach-shmobile/ use
names of power domains instead of pointers to domain objects for
adding devices to the domains.  This will allow us to put the
domain objects into tables and register them all in one shot
going forward.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Make it possible to use domain names in operations connecting cpuidle
to and disconnecting it from a PM domain.  This is useful on
platforms where PM domain objects are organized in such a way that
the names of the domains are easier to use than the addresses of
those objects.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

The names of the cpuidle-related functions in
drivers/base/power/domain.c are inconsistent with the names of the
other exported functions in that file (the "pm_" prefix is missing
from them) and they are missing kerneldoc comments.

Fix that by adding the missing "pm_" prefix to the names of those
functions and add kerneldoc comments documenting them.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

It sometimes is necessary to turn on a given PM domain when only
the name of it is known and the domain pointer is not readily
available.  For this reason, add a new helper function,
pm_genpd_name_poweron(), allowing the caller to turn on a PM domain
using its name for identification.  To avoid code duplication,
move the domain lookup code to a separate function.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Add a new helper function, pm_genpd_add_subdomain_names(), allowing
the caller to add a subdomain to a generic PM domain using names for
domain identification (both domains have to be initialized before).

This function is useful for adding subdomains to PM domains whose
representations are stored in tables, when the caller doesn't know
the indices of the domain to add the subdomain to and of the
subdomain itself, but it knows the domains' names.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Add a new helper function __pm_genpd_name_add_device() allowing
a device to be added to a (registered) generic PM domain identified
by name.  Add a wrapper around it, pm_genpd_name_add_device(),
passing NULL as the last argument and reorganize pm_domains.h for the
new functions to be defined consistently with the existing ones.

These functions are useful for adding devices to PM domains whose
representations are stored in tables, when the caller doesn't know
the index of the domain to add the device to, but it knows the
domain's name.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

The syscore device PM flag used to mark the devices (belonging to
PM domains) that should never be turned off, except for the system
core (syscore) suspend/hibernation and resume stages, need not be
accessed by the runtime PM core functions, because all of the devices
it is set for need to be marked as "irq safe" anyway and are
protected from being turned off by runtime PM by ensuring that their
usage counters are always set.

For this reason, make the syscore flag system-wide PM-specific
and simplify the code used for manipulating it, because it need not
acquire the device's power.lock any more.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Modify the SH MTU2 clock event device driver to support runtime PM at
a basic level (i.e. device clocks can be disabled and enabled, but
domain power must be on, because the device has to be marked as
"irq safe").
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Modify the SH CMT clock source/clock event device driver to support
runtime PM at a basic level (i.e. device clocks can be disabled and
enabled, but domain power must be on, because the devices have to
be marked as "irq safe").
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Modify the SH TMU clock source/clock event device driver to support
runtime PM at a basic level (i.e. device clocks can be disabled and
enabled, but domain power must be on, because the devices have to
be marked as "irq safe").
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

The genpd_start_dev() routine used by pm_genpd_runtime_resume()
to put "irq safe" devices into the full power state measures the
time necessary to "start" the device and updates its PM QoS timing
data if necessary.  This may lead to a deadlock if the given device
is a clock source and genpd_start_dev() is invoked from within the
clock source's .enable() routine, which will happen if that routine
uses pm_runtime_get_sync(), for example, to ensure that the device
is operational.

For this reason, introduce a special routine analogous to
genpd_start_dev(), called genpd_start_dev_no_timing(), that doesn't
carry out the time measurement, and make pm_genpd_runtime_resume()
use it instead of genpd_start_dev() to power up "irq safe" devices.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

The syscore device PM flag is used to mark the devices (belonging to
a PM domain) that should never be turned off, except for the system
core (syscore) suspend/hibernation and resume stages.  That flag is
stored in the device's struct pm_subsys_data object whose address is
available from struct device.  However, in some situations it may be
convenient to set that flag before the device is added to a PM
domain, so it is better to move it directly to the "power" member of
struct device.  Then, it can be checked by the routines in
drivers/base/power/runtime.c and drivers/base/power/main.c, which is
more straightforward.

This also reduces the number of dev_gpd_data() invocations in the
generic PM domains framework, so the overhead related to the syscore
flag is slightly smaller.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

The always_on device flag is used to mark the devices (belonging to
a PM domain) that should never be turned off, except for the system
core (syscore) suspend/hibernation and resume stages.  Change name
of that flag to "syscore" to better reflect its purpose.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Runtime PM helper functions, like pm_runtime_get_sync(), cannot be
called by early platform device drivers, because the devices' power
management locks are not initialized at that time.  This is quite
inconvenient, so modify early_platform_add_devices() to initialize
the devices power management locks as appropriate and make sure that
they won't be initialized more than once if an early platform
device is going to be used as a regular one later.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Make the device power management initialization more straightforward
by moving the initialization of common (i.e. used by both runtime PM
and system suspend) fields to a separate routine.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Introduce suspend/resume routines for SH MTU2 clock event devices
such that if those devices belong to a PM domain, the generic PM
domains framework will be notified that the given domain may be
turned off (during system suspend) or that it has to be turned on
(during system resume).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Introduce suspend/resume routines for SH CMT clock event devices and
modify the suspend/resume routines for SH CMT clock sources such that
if those devices belong to a PM domain, the generic PM domains
framework will be notified that the given domain may be turned off
(during system suspend) or that it has to be turned on (during system
resume).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Introduce suspend/resume routines for SH TMU clock source and
clock event device such that if those devices belong to a PM domain,
the generic PM domains framework will be notified that the given
domain may be turned off (during system suspend) or that it has to
be turned on (during system resume).

This change allows the A4R domain on SH7372 to be turned off during
system suspend (tested on the Mackerel board) if the TMU clock source
and/or clock event device is in use.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

Some clock event devices, for example such that belong to PM domains,
need to be handled in a spcial way during the timekeeping suspend
and resume (which takes place in the system core, or "syscore",
stages of system power transitions) in analogy with clock sources.

Introduce .suspend() and .resume() callbacks for clock event devices
that will be executed by timekeeping_suspend/_resume(), respectively,
next the the clock sources' .suspend() and .resume() callbacks.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Introduce function pm_genpd_syscore_switch() and two wrappers around
it, pm_genpd_syscore_poweroff() and pm_genpd_syscore_poweron(),
allowing the callers to let the generic PM domains framework know
that the given device is not necessary any more and its PM domain
can be turned off (the former) or that the given device will be
required immediately, so its PM domain has to be turned on (the
latter) during the system core (syscore) stage of system suspend
(or hibernation) and resume.

These functions will be used for handling devices registered as
clock sources and clock event devices that belong to PM domains.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Introduce function pm_genpd_sync_poweron() for restoring domain power
during resume from system suspend and hibernation.  It can be much
simpler than pm_genpd_poweron(), because it doesn't have to care
about locking and it can skip many checks done by the latter.

Modify pm_genpd_resume_noirq() and pm_genpd_restore_noirq() to use
the new function.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Andreas Bombe reported that the added ktime_t overflow checking added to
timespec_valid in commit 4e8b1452 ("time: Improve sanity checking of
timekeeping inputs") was causing problems with X.org because it caused
timeouts larger then KTIME_T to be invalid.

Previously, these large timeouts would be clamped to KTIME_MAX and would
never expire, which is valid.

This patch splits the ktime_t overflow checking into a new
timespec_valid_strict function, and converts the timekeeping codes
internal checking to use this more strict function.
Reported-and-tested-by: Andreas Bombe <aeb@debian.org>
Cc: Zhouping Liu <zliu@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>