Commit Graph

78 Commits

Author SHA1 Message Date
Rafael J. Wysocki
45f0a85c82 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>
2013-06-03 21:49:52 +02:00
Ulf Hansson
841670351e PM / Runtime: Improve prepare handling at system suspend for genpd
When genpd prepares for a system suspend it will fetch a runtime
reference for the device. When returning it we now use the
asyncronous runtime PM API. Thus we don't have to wait for the
device to become idle|suspended before we 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>
2013-04-12 13:34:57 +02:00
Ulf Hansson
af93933974 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>
2013-04-12 13:34:57 +02:00
Tejun Heo
a4ca26a43e PM / Domains: don't use [delayed_]work_pending()
There's no need to test whether a (delayed) work item is pending
before queueing, flushing or cancelling it, so remove work_pending()
tests used in those cases.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-26 00:39:11 +01:00
Rafael J. Wysocki
c8b6817103 Merge branch 'pm-qos'
* pm-qos:
  PM / QoS: Handle device PM QoS flags while removing constraints
  PM / QoS: Resume device before exposing/hiding PM QoS flags
  PM / QoS: Document request manipulation requirement for flags
  PM / QoS: Fix a free error in the dev_pm_qos_constraints_destroy()
  PM / QoS: Fix the return value of dev_pm_qos_update_request()
  PM / ACPI: Take device PM QoS flags into account
  PM / Domains: Check device PM QoS flags in pm_genpd_poweroff()
  PM / QoS: Make it possible to expose PM QoS device flags to user space
  PM / QoS: Introduce PM QoS device flags support
  PM / QoS: Prepare struct dev_pm_qos_request for more request types
  PM / QoS: Introduce request and constraint data types for PM QoS flags
  PM / QoS: Prepare device structure for adding more constraint types
2012-11-29 21:40:32 +01:00
Rafael J. Wysocki
34b1f76275 PM / Domains: Check device PM QoS flags in pm_genpd_poweroff()
Make the generic PM domains pm_genpd_poweroff() function take
device PM QoS flags into account when deciding whether or not to
remove power from the domain.

After this change the routine will return -EBUSY without executing
the domain's .power_off() callback if there is at least one PM QoS
flags request for at least one device in the domain and at least of
those request has at least one of the NO_POWER_OFF and REMOTE_WAKEUP
flags set.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: mark gross <markgross@thegnar.org>
2012-10-24 02:08:30 +02:00
jhbird.choi@samsung.com
debe081aaa PM / Domains: Fix memory leak on error path in pm_genpd_attach_cpuidle
If pm_genpd_attach_cpudidle failed we leak memory stored in 'cpu_data'.

Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-10-23 00:54:38 +02:00
Sachin Kamat
b3d3b9fb60 PM / Domains: Fix compilation warning related to genpd_start_dev_no_timing()
Function genpd_start_dev_no_timing was accessed inside CONFIG_PM_RUNTIME
macro but defined outside it. When the above macro was not defined the
compiler gave the following warning:

drivers/base/power/domain.c:96:12: warning:
‘genpd_start_dev_no_timing’ defined but not used [-Wunused-function]

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-06 23:10:53 +02:00
Rafael J. Wysocki
74a2799ab5 PM / Domains: Operations related to cpuidle using domain names
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>
2012-09-04 01:36:53 +02:00
Rafael J. Wysocki
40114447a7 PM / Domains: Document cpuidle-related functions and change their names
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>
2012-09-04 01:36:53 +02:00
Rafael J. Wysocki
8bc0251de2 PM / Domains: Add power-on function using names to identify domains
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>
2012-09-04 01:36:53 +02:00
Rafael J. Wysocki
fb7268be9f PM / Domains: Make it possible to use names when adding subdomains
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>
2012-09-04 01:36:52 +02:00
Rafael J. Wysocki
b5abb085f5 PM / Domains: Make it possible to use domain names when adding devices
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>
2012-09-04 01:36:52 +02:00
Rafael J. Wysocki
feb70af0e3 PM: Do not use the syscore flag for runtime PM
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>
2012-09-04 01:36:05 +02:00
Rafael J. Wysocki
e2e3e4e51e PM / Domains: Do not measure start time for "irq safe" devices
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>
2012-09-04 01:36:04 +02:00
Rafael J. Wysocki
dbf374142d PM / Domains: Move syscore flag from subsys data to struct device
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>
2012-09-04 01:36:04 +02:00
Rafael J. Wysocki
6fb28badf2 PM / Domains: Rename the always_on device flag to syscore
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>
2012-09-04 01:36:03 +02:00
Rafael J. Wysocki
77f827de07 PM / Domains: Add power off/on function for system core suspend stage
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>
2012-09-04 01:36:01 +02:00
Rafael J. Wysocki
802d8b49a7 PM / Domains: Introduce simplified power on routine for system resume
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>
2012-09-04 01:36:00 +02:00
Rafael J. Wysocki
8e9afafdad PM / Domains: Fix build warning for CONFIG_PM_RUNTIME unset
The functions genpd_save_dev() and genpd_restore_dev() are not used
for CONFIG_PM_RUNTIME unset, so move them under an appropriate
#ifdef.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-12 22:39:49 +02:00
Sachin Kamat
db79e53dd5 PM / Domains: Replace plain integer with NULL pointer in domain.c file
Fixes the following sparse warning:
drivers/base/power/domain.c:1679:55: warning: Using plain integer as NULL pointer

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-11 12:25:49 +02:00
Sachin Kamat
8951ef0219 PM / Domains: Add missing static storage class specifier in domain.c file
Fixes the folloiwng sparse warning:
drivers/base/power/domain.c:149:5:
warning: symbol '__pm_genpd_poweron' was not declared. Should it be static?

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-10 21:47:07 +02:00
Rafael J. Wysocki
62d4490294 PM / Domains: Allow device callbacks to be added at any time
Make it possible to modify device callbacks used by the generic PM
domains core code at any time, not only after the device has been
added to a domain.  This will allow device drivers to provide their
own device PM domain callbacks even if they are registered before
adding the devices to PM domains.

For this purpose, use the observation that the struct
generic_pm_domain_data object containing the relevant callback
pointers may be allocated by pm_genpd_add_callbacks() and the
callbacks may be set before __pm_genpd_add_device() is run for
the given device.  This object will then be used by
__pm_genpd_add_device(), but it has to be protected from
premature removal by reference counting.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-05 22:12:54 +02:00
Rafael J. Wysocki
1d5fcfec22 PM / Domains: Add device domain data reference counter
Add a mechanism for counting references to the
struct generic_pm_domain_data object pointed to by
dev->power.subsys_data->domain_data if the device in question
belongs to a generic PM domain.

This change is necessary for a subsequent patch making it possible to
allocate that object from within pm_genpd_add_callbacks(), so that
drivers can attach their PM domain device callbacks to devices before
those devices are added to PM domains.

This patch has been tested on the SH7372 Mackerel board.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-05 22:12:32 +02:00
Rafael J. Wysocki
cbc9ef0287 PM / Domains: Add preliminary support for cpuidle, v2
On some systems there are CPU cores located in the same power
domains as I/O devices.  Then, power can only be removed from the
domain if all I/O devices in it are not in use and the CPU core
is idle.  Add preliminary support for that to the generic PM domains
framework.

First, the platform is expected to provide a cpuidle driver with one
extra state designated for use with the generic PM domains code.
This state should be initially disabled and its exit_latency value
should be set to whatever time is needed to bring up the CPU core
itself after restoring power to it, not including the domain's
power on latency.  Its .enter() callback should point to a procedure
that will remove power from the domain containing the CPU core at
the end of the CPU power transition.

The remaining characteristics of the extra cpuidle state, referred to
as the "domain" cpuidle state below, (e.g. power usage, target
residency) should be populated in accordance with the properties of
the hardware.

Next, the platform should execute genpd_attach_cpuidle() on the PM
domain containing the CPU core.  That will cause the generic PM
domains framework to treat that domain in a special way such that:

 * When all devices in the domain have been suspended and it is about
   to be turned off, the states of the devices will be saved, but
   power will not be removed from the domain.  Instead, the "domain"
   cpuidle state will be enabled so that power can be removed from
   the domain when the CPU core is idle and the state has been chosen
   as the target by the cpuidle governor.

 * When the first I/O device in the domain is resumed and
   __pm_genpd_poweron(() is called for the first time after
   power has been removed from the domain, the "domain" cpuidle
   state will be disabled to avoid subsequent surprise power removals
   via cpuidle.

The effective exit_latency value of the "domain" cpuidle state
depends on the time needed to bring up the CPU core itself after
restoring power to it as well as on the power on latency of the
domain containing the CPU core.  Thus the "domain" cpuidle state's
exit_latency has to be recomputed every time the domain's power on
latency is updated, which may happen every time power is restored
to the domain, if the measured power on latency is greater than
the latency stored in the corresponding generic_pm_domain structure.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Kevin Hilman <khilman@ti.com>
2012-07-03 19:07:42 +02:00
Rafael J. Wysocki
80de3d7f41 PM / Domains: Do not stop devices after restoring their states
While resuming a device belonging to a PM domain,
pm_genpd_runtime_resume() calls __pm_genpd_restore_device() to
restore its state, if necessary.  The latter starts the device,
using genpd_start_dev(), restores its state, using
genpd_restore_dev(), and then stops it, using genpd_stop_dev().
However, this last operation is not necessary, because the
device is supposed to be operational after pm_genpd_runtime_resume()
has returned and because of it pm_genpd_runtime_resume() has to
call genpd_start_dev() once again for the "restored" device, which
is inefficient.

To make things more efficient, remove the call to genpd_stop_dev()
from __pm_genpd_restore_device() and the direct call to
genpd_start_dev() from pm_genpd_runtime_resume().  [Of course,
genpd_start_dev() still has to be called by it for devices with the
power.irq_safe flag set, because __pm_genpd_restore_device() is not
executed for them.]

This change has been tested on the SH7372 Mackerel board.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-01 13:31:29 +02:00
Rafael J. Wysocki
0b589741b8 PM / Domains: Use subsystem runtime suspend/resume callbacks by default
Currently, the default "save state" and "restore state" routines
for generic PM domains, pm_genpd_default_save_state() and
pm_genpd_default_restore_state(), respectively, only use runtime PM
callbacks provided by device drivers, but in general those callbacks
need not provide the entire necessary functionality.  Namely, in
general it may be necessary to execute subsystem (i.e. device type,
device class or bus type) callbacks that will carry out all of the
necessary operations.

For this reason, modify pm_genpd_default_save_state() and
pm_genpd_default_restore_state() to execute subsystem callbacks,
if they are provided, and fall back to driver callbacks otherwise.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-01 13:31:29 +02:00
Rafael J. Wysocki
ca1d72f033 PM / Domains: Make it possible to add devices to inactive domains
The generic PM domains core code currently requires domains to be in
the "power on" state for adding devices to them, but this limitation
turns out to be inconvenient in some situations, so remove it.

For this purpose, make __pm_genpd_add_device() set the device's
need_restore flag if the domain is in the "power off" state, so that
the device's "restore state" (usually .runtime_resume()) callback
is executed when it is resumed after the domain has been turned on.
If the domain is in the "power on" state, the device's need_restore
flag will be cleared by __pm_genpd_add_device(), so that its "save
state" (usually .runtime_suspend()) callback is executed when the
domain is about to be turned off.  However, since that default
behavior need not be always desirable, add a helper function
pm_genpd_dev_need_restore() allowing a device's need_restore flag
to be set/unset at any time.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-18 20:45:26 +02:00
Huang Ying
4fcac10d28 PM / Domains: Fix link checking when add subdomain
Current pm_genpd_add_subdomain() will allow duplicated link between
master and slave domain.  This patch fixed it.

Because when current pm_genpd_add_subdomain() checks whether the link
between the master and slave generic PM domain already exists,
slave_links instead of master_links of master domain is used.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-11 21:11:37 +02:00
Rafael J. Wysocki
6ff7bb0d02 PM / Domains: Cache device stop and domain power off governor results, v3
The results of the default device stop and domain power off governor
functions for generic PM domains, default_stop_ok() and
default_power_down_ok(), depend only on the timing data of devices,
which are static, and on their PM QoS constraints.  Thus, in theory,
these functions only need to carry out their computations, which may
be time consuming in general, when it is known that the PM QoS
constraint of at least one of the devices in question has changed.

Use the PM QoS notifiers of devices to implement that.  First,
introduce new fields, constraint_changed and max_off_time_changed,
into struct gpd_timing_data and struct generic_pm_domain,
respectively, and register a PM QoS notifier function when adding
a device into a domain that will set those fields to 'true' whenever
the device's PM QoS constraint is modified.  Second, make
default_stop_ok() and default_power_down_ok() use those fields to
decide whether or not to carry out their computations from scratch.

The device and PM domain hierarchies are taken into account in that
and the expense is that the changes of PM QoS constraints of
suspended devices will not be taken into account immediately, which
isn't guaranteed anyway in general.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-05 21:51:58 +02:00
Rafael J. Wysocki
efa6902501 PM / Domains: Make device removal more straightforward
The removal of a device from a PM domain doesn't have to browse
the domain's device list, because it can check directly if the
device belongs to the given domain.  Moreover, it should clear
the domain_data pointer in dev->power.subsys_data, because
dev_pm_put_subsys_data(dev) may not remove dev->power.subsys_data
and the stale domain data pointer may cause problems to happen.

Rework pm_genpd_remove_device() taking the above observations into
account.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-05 21:51:50 +02:00
Rafael J. Wysocki
76e267d822 PM / Runtime: Remove device fields related to suspend time, v2
After the previous changes in default_stop_ok() and
default_power_down_ok() for PM domains, there are two fields in
struct dev_pm_info that aren't necessary any more,  suspend_time
and max_time_suspended_ns.

Remove those fields along with all of the code that accesses them,
which simplifies the runtime PM framework quite a bit.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-01 21:28:38 +02:00
Rafael J. Wysocki
dd8683e97f PM / Domains: Rework default domain power off governor function, v2
The existing default domain power down governor function for PM
domains, default_power_down_ok(), is supposed to check whether or not
the PM QoS latency constraints of the devices in the domain will be
violated if the domain is turned off by pm_genpd_poweroff().
However, the computations carried out by it don't reflect the
definition of the PM QoS latency constrait in
Documentation/ABI/testing/sysfs-devices-power.

Make default_power_down_ok() follow the definition of the PM QoS
latency constrait.  In particular, make it only take latencies into
account, because it doesn't matter how much time has elapsed since
the domain's devices were suspended for the computation.

Remove the break_even_ns and power_off_time fields from
struct generic_pm_domain, because they are not necessary any more.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-01 21:28:15 +02:00
Rafael J. Wysocki
a5bef810ad PM / Domains: Rework default device stop governor function, v2
The existing default device stop governor function for PM domains,
default_stop_ok(), is supposed to check whether or not the device's
PM QoS latency constraint will be violated if the device is stopped
by pm_genpd_runtime_suspend().  However, the computations carried out
by it don't reflect the definition of the PM QoS latency constrait in
Documentation/ABI/testing/sysfs-devices-power.

Make default_stop_ok() follow the definition of the PM QoS latency
constrait.  In particular, make it take the device's start and stop
latencies correctly.

Add a new field, effective_constraint_ns, to struct gpd_timing_data
and use it to store the difference between the device's PM QoS
constraint and its resume latency for use by the device's parent
(the effective_constraint_ns values for the children are used for
computing the parent's one along with its PM QoS constraint).

Remove the break_even_ns field from struct gpd_timing_data, because
it's not used any more.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-01 21:28:03 +02:00
Rafael J. Wysocki
18dd2ece3c PM / Domains: Check domain status during hibernation restore of devices
Power domains that were off before hibernation shouldn't be turned on
during device restore, so prevent that from happening.

This change fixes up commit 65533bbf63

    PM / Domains: Fix hibernation restore of devices, v2

that didn't include it by mistake.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-03-19 10:38:14 +01:00
Rafael J. Wysocki
1e78a0c7fc PM / Domains: Introduce "always on" device flag
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>
Cc: stable@vger.kernel.org
2012-03-16 21:44:59 +01:00
Rafael J. Wysocki
65533bbf63 PM / Domains: Fix hibernation restore of devices, v2
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>
Cc: stable@vger.kernel.org
2012-03-16 21:44:48 +01:00
Rafael J. Wysocki
cc85b20780 PM / Domains: Fix handling of wakeup devices during system resume
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>
Cc: stable@vger.kernel.org
2012-03-16 21:44:41 +01:00
Rafael J. Wysocki
dcaad77a80 Merge branch 'v3.4-for-rafael' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into pm-domains
* 'v3.4-for-rafael' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
  ARM: EXYNOS: Hook up power domains to generic power domain infrastructure
  PM / Domains: Add OF support
2012-02-01 22:18:43 +01:00
Rafael J. Wysocki
0496c8ae36 PM / Domains: Run late/early device suspend callbacks at the right time
After the introduction of the late/early phases of device
suspend/resume during system-wide power transitions it is possible
to make the generic PM domains code execute its default late/early
device suspend/resume callbacks during those phases instead of the
corresponding _noirq phases.  The _noirq device suspend/resume
phases were only used for executing those callbacks, because this
was the only way it could be done, but now we can do better.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-29 20:39:02 +01:00
Thomas Abraham
c8aa130b74 PM / Domains: Add OF support
A device node pointer is added to generic pm domain structure to associate
the domain with a node in the device tree. The platform code parses the
device tree to find available nodes representing the generic power domain,
instantiates the available domains and initializes them by calling
pm_genpd_init().

Nodes representing the devices include a phandle of the power domain to
which it belongs. As these devices get instantiated, the driver code
checkes for availability of a power domain phandle, converts the phandle
to a device node and uses the new pm_genpd_of_add_device() api to
associate the device with a power domain.

pm_genpd_of_add_device() runs through its list of registered power domains
and matches the OF node of the domain with the one specified as the
parameter. If a match is found, the device is associated with the matched
domain.

Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-01-27 15:22:07 +09:00
Rafael J. Wysocki
0f1d6986ba PM / Domains: Fix build for CONFIG_PM_SLEEP unset
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>
2012-01-14 00:39:25 +01:00
Rafael J. Wysocki
c9914854b4 PM / Domains: Fix default system suspend/resume operations
Commit d23b9b00cd (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>
2011-12-08 22:59:23 +01:00
Rafael J. Wysocki
e84b2c2027 PM / Domains: Make it possible to assign names to generic PM domains
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>
2011-12-06 22:19:54 +01:00
Rafael J. Wysocki
0140d8bd47 PM / Domains: Automatically update overoptimistic latency information
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>
2011-12-01 21:48:07 +01:00
Rafael J. Wysocki
221e9b5838 PM / Domains: Add default power off governor function (v4)
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>
2011-12-01 21:47:58 +01:00
Rafael J. Wysocki
b02c999ac3 PM / Domains: Add device stop governor function (v4)
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>
2011-12-01 21:47:40 +01:00
Rafael J. Wysocki
d23b9b00cd PM / Domains: Rework system suspend callback routines (v2)
The current generic PM domains code attempts to use the generic
system suspend operations along with the domains' device stop/start
routines, which requires device drivers to assume that their
system suspend/resume (and hibernation/restore) callbacks will always
be used with generic PM domains.  However, in theory, the same
hardware may be used in devices that don't belong to any PM domain,
in which case it would be necessary to add "fake" PM domains to
satisfy the above assumption.  Also, the domain the hardware belongs
to may not be handled with the help of the generic code.

To allow device drivers that may be used along with the generic PM
domains code of more flexibility, add new device callbacks,
.suspend(), .suspend_late(), .resume_early(), .resume(), .freeze(),
.freeze_late(), .thaw_early(), and .thaw(), that can be supplied by
the drivers in addition to their "standard" system suspend and
hibernation callbacks.  These new callbacks, if defined, will be used
by the generic PM domains code for the handling of system suspend and
hibernation instead of the "standard" ones.  This will allow drivers
to be designed to work with generic PM domains as well as without
them.

For backwards compatibility, introduce default implementations of the
new callbacks for PM domains that will execute pm_generic_suspend(),
pm_generic_suspend_noirq(), pm_generic_resume_noirq(),
pm_generic_resume(), pm_generic_freeze(), pm_generic_freeze_noirq(),
pm_generic_thaw_noirq(), and pm_generic_thaw(), respectively, for the
given device if its driver doesn't define those callbacks.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-01 21:47:29 +01:00
Rafael J. Wysocki
ecf00475f2 PM / Domains: Introduce "save/restore state" device callbacks
The current PM domains code uses device drivers' .runtime_suspend()
and .runtime_resume() callbacks as the "save device state" and
"restore device state" operations, which may not be appropriate in
general, because it forces drivers to assume that they always will
be used with generic PM domains.  However, in theory, the same
hardware may be used in devices that don't belong to any PM
domain, in which case it would be necessary to add "fake" PM
domains to satisfy the above assumption.  It also may be located in
a PM domain that's not handled with the help of the generic code.

To allow device drivers that may be used along with the generic PM
domains code of more flexibility, introduce new device callbacks,
.save_state() and .restore_state(), that can be supplied by the
drivers in addition to their "standard" runtime PM callbacks.  This
will allow the drivers to be designed to work with generic PM domains
as well as without them.

For backwards compatibility, introduce default .save_state() and
.restore_state() callback routines for PM domains that will execute
a device driver's .runtime_suspend() and .runtime_resume() callbacks,
respectively, for the given device if the driver doesn't provide its
own implementations of .save_state() and .restore_state().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-01 21:47:18 +01:00
Rafael J. Wysocki
d5e4cbfe20 PM / Domains: Make it possible to use per-device domain callbacks
The current generic PM domains code requires that the same .stop(),
.start() and .active_wakeup() device callback routines be used for
all devices in the given domain, which is inflexible and may not
cover some specific use cases.  For this reason, make it possible to
use device specific .start()/.stop() and .active_wakeup() callback
routines by adding corresponding callback pointers to struct
generic_pm_domain_data.  Add a new helper routine,
pm_genpd_register_callbacks(), that can be used to populate
the new per-device callback pointers.

Modify the shmobile's power domains code to allow drivers to add
their own code to be run during the device stop and start operations
with the help of the new callback pointers.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
2011-12-01 21:47:08 +01:00