Local variable 'error' in dev_pm_qos_add_ancestor_request() need
not contain error codes only, so rename it to 'ret'.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* 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
PM QoS flags have to be handled by dev_pm_qos_constraints_destroy()
in the same way as PM QoS resume latency constraints. That is, if
they have been exposed to user space, they have to be hidden from it
and the list of flags requests has to be flushed before destroying
the device's PM QoS object. Make that happen.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
dev_pm_qos_add_request() can return 0, 1, or a negative error code,
therefore the correct error test is "if (error < 0)." Checking just for
non-zero return code leads to erroneous setting of the req->dev pointer
to NULL, which then leads to a repeated call to
dev_pm_qos_add_ancestor_request() in st1232_ts_irq_handler(). This in turn
leads to an Oops, when the I2C host adapter is unloaded and reloaded again
because of the inconsistent state of its QoS request list.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When PM runtime is enabled in DaVinci and the machine migrates to
common clk framework, the clk_enable() gets called without
clk_prepare(). This patch is to fix this issue so that PM run
time can inter work with common clk framework.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The callback function of call_rcu() just calls a kfree(), so we
can use kfree_rcu() instead of call_rcu() + callback function.
dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently the opp_find* functions return -ENODEV when:
a) it cant find a device (e.g. request for an OPP search on device
which was not registered)
b) When it cant find a match for the search strategy used
This makes life a little in-efficient for users such as devfreq
to make reasonable judgement before switching search strategies.
So, standardize the return results as following:
-EINVAL for bad pointer parameters
-ENODEV when device cannot be found
-ERANGE when search fails
This has the following benefit for devfreq implementation:
The search fails when an unregistered device pointer is provided.
This is a trigger to change the search direction and search for
a better fit, however, if we cannot differentiate between a valid
search range failure Vs an unregistered device, second search goes
through the same fail return condition. This can be avoided by
appropriate handling of error return code.
With this change, we also fix devfreq for the improved search
strategy with updated error code.
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Export the OPP functions for use by driver modules.
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kevin Hilman <khilman@ti.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
[nm@ti.com: expansion of functions exported]
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Liam Girdwood <lrg@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
synchronize_rcu() blocks the caller of opp_enable/disbale
for a complete grace period. This blocking duration prevents
any intensive use of the functions. Replace synchronize_rcu()
by call_rcu() which will call our function for freeing the old
opp element.
The duration of opp_enable() and opp_disable() will be no more
dependant of the grace period.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since dev_pm_qos_add_request(), dev_pm_qos_update_request() and
dev_pm_qos_remove_request() for PM QoS flags should not be invoked
when device in RPM_SUSPENDED, add pm_runtime_get_sync() and pm_runtime_put()
around these functions in dev_pm_qos_expose_flags() and
dev_pm_qos_hide_flags().
[rjw: Modified the subject and changelog to better reflect the code
changes made.]
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In fact, the callers of dev_pm_qos_add_request(),
dev_pm_qos_update_request() and dev_pm_qos_remove_request() for
requests of type DEV_PM_QOS_FLAGS need to ensure that the target
device is not RPM_SUSPENDED before using any of these functions (or
be prepared for the new PM QoS flags to take effect after the device
has been resumed). Document this in their kerneldoc comments.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Free a wrong point to struct dev_pm_qos->latency which suppose to
be the point to struct dev_pm_qos. The patch is to fix the issue.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit e39473d (PM / QoS: Make it possible to expose PM QoS device
flags to user space) introduced __dev_pm_qos_update_request() to be
called internally by dev_pm_qos_update_request(), but forgot to make
the latter actually use the return value of the former. Fix this
mistake.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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>
Define two device PM QoS flags, PM_QOS_FLAG_NO_POWER_OFF
and PM_QOS_FLAG_REMOTE_WAKEUP, and introduce routines
dev_pm_qos_expose_flags() and dev_pm_qos_hide_flags() allowing the
caller to expose those two flags to user space or to hide them
from it, respectively.
After the flags have been exposed, user space will see two
additional sysfs attributes, pm_qos_no_power_off and
pm_qos_remote_wakeup, under the device's /sys/devices/.../power/
directory. Then, writing 1 to one of them will update the
PM QoS flags request owned by user space so that the corresponding
flag is requested to be set. In turn, writing 0 to one of them
will cause the corresponding flag in the user space's request to
be cleared (however, the owners of the other PM QoS flags requests
for the same device may still request the flag to be set and it
may be effectively set even if user space doesn't request that).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
Acked-by: mark gross <markgross@thegnar.org>
Modify the device PM QoS core code to support PM QoS flags requests.
First, add a new field of type struct pm_qos_flags called "flags"
to struct dev_pm_qos for representing the list of PM QoS flags
requests for the given device. Accordingly, add a new "type" field
to struct dev_pm_qos_request (along with an enum for representing
request types) and a new member called "flr" to its data union for
representig flags requests.
Second, modify dev_pm_qos_add_request(), dev_pm_qos_update_request(),
the internal routine apply_constraint() used by them and their
existing callers to cover flags requests as well as latency
requests. In particular, dev_pm_qos_add_request() gets a new
argument called "type" for specifying the type of a request to be
added.
Finally, introduce two routines, __dev_pm_qos_flags() and
dev_pm_qos_flags(), allowing their callers to check which PM QoS
flags have been requested for the given device (the caller is
supposed to pass the mask of flags to check as the routine's
second argument and examine its return value for the result).
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>
The subsequent patches will use struct dev_pm_qos_request for
representing both latency requests and flags requests. To make that
easier, put the node member of struct dev_pm_qos_request (under the
name "pnode") into a union called "data" that will represent the
request's value and list node depending on its type.
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>
Currently struct dev_pm_info contains only one PM QoS constraints
pointer reserved for latency requirements. Since one more device
constraints type (i.e. flags) will be necessary, introduce a new
structure, struct dev_pm_qos, that eventually will contain all of
the available device PM QoS constraints and replace the "constraints"
pointer in struct dev_pm_info with a pointer to the new structure
called "qos".
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
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>
* Improved system suspend/resume and runtime PM handling for the SH TMU, CMT
and MTU2 clock event devices (also used by ARM/shmobile).
* Generic PM domains framework extensions related to cpuidle support and
domain objects lookup using names.
* ARM/shmobile power management updates including improved support for the
SH7372's A4S power domain containing the CPU core.
* cpufreq changes related to AMD CPUs support from Matthew Garrett, Andre
Przywara and Borislav Petkov.
* cpu0 cpufreq driver from Shawn Guo.
* cpufreq governor fixes related to the relaxing of limit from Michal Pecio.
* OMAP cpufreq updates from Axel Lin and Richard Zhao.
* cpuidle ladder governor fixes related to the disabling of states from
Carsten Emde and me.
* Runtime PM core updates related to the interactions with the system suspend
core from Alan Stern and Kevin Hilman.
* Wakeup sources modification allowing more helper functions to be called from
interrupt context from John Stultz and additional diagnostic code from Todd
Poynor.
* System suspend error code path fix from Feng Hong.
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Merge tag 'pm-for-3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael J Wysocki:
- Improved system suspend/resume and runtime PM handling for the SH
TMU, CMT and MTU2 clock event devices (also used by ARM/shmobile).
- Generic PM domains framework extensions related to cpuidle support
and domain objects lookup using names.
- ARM/shmobile power management updates including improved support for
the SH7372's A4S power domain containing the CPU core.
- cpufreq changes related to AMD CPUs support from Matthew Garrett,
Andre Przywara and Borislav Petkov.
- cpu0 cpufreq driver from Shawn Guo.
- cpufreq governor fixes related to the relaxing of limit from Michal
Pecio.
- OMAP cpufreq updates from Axel Lin and Richard Zhao.
- cpuidle ladder governor fixes related to the disabling of states from
Carsten Emde and me.
- Runtime PM core updates related to the interactions with the system
suspend core from Alan Stern and Kevin Hilman.
- Wakeup sources modification allowing more helper functions to be
called from interrupt context from John Stultz and additional
diagnostic code from Todd Poynor.
- System suspend error code path fix from Feng Hong.
Fixed up conflicts in cpufreq/powernow-k8 that stemmed from the
workqueue fixes conflicting fairly badly with the removal of support for
hardware P-state chips. The changes were independent but somewhat
intertwined.
* tag 'pm-for-3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits)
Revert "PM QoS: Use spinlock in the per-device PM QoS constraints code"
PM / Runtime: let rpm_resume() succeed if RPM_ACTIVE, even when disabled, v2
cpuidle: rename function name "__cpuidle_register_driver", v2
cpufreq: OMAP: Check IS_ERR() instead of NULL for omap_device_get_by_hwmod_name
cpuidle: remove some empty lines
PM: Prevent runtime suspend during system resume
PM QoS: Use spinlock in the per-device PM QoS constraints code
PM / Sleep: use resume event when call dpm_resume_early
cpuidle / ACPI : move cpuidle_device field out of the acpi_processor_power structure
ACPI / processor: remove pointless variable initialization
ACPI / processor: remove unused function parameter
cpufreq: OMAP: remove loops_per_jiffy recalculate for smp
sections: fix section conflicts in drivers/cpufreq
cpufreq: conservative: update frequency when limits are relaxed
cpufreq / ondemand: update frequency when limits are relaxed
properly __init-annotate pm_sysrq_init()
cpufreq: Add a generic cpufreq-cpu0 driver
PM / OPP: Initialize OPP table from device tree
ARM: add cpufreq transiton notifier to adjust loops_per_jiffy for smp
cpufreq: Remove support for hardware P-state chips from powernow-k8
...
This reverts commit fc2fb3a075.
The problem with the above commit is that it makes the device PM QoS
core code hold a spinlock around blocking_notifier_call_chain()
invocations.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
There are several drivers where the return value of
pm_runtime_get_sync() is used to decide whether or not it is safe to
access hardware and that don't provide .suspend() callbacks for system
suspend (but may use late/noirq callbacks.) If such a driver happens
to call pm_runtime_get_sync() during system suspend, after the core
has disabled runtime PM, it will get the error code and will decide
that the hardware should not be accessed, although this may be a wrong
conclusion, depending on the state of the device when runtime PM was
disabled.
Drivers might work around this problem by using a test like:
ret = pm_runtime_get_sync(dev);
if (!ret || (ret == -EACCES && driver_private_data(dev)->suspended)) {
/* access hardware */
}
where driver_private_data(dev)->suspended is a flag set by the
driver's .suspend() method (that would have to be added for this
purpose). However, that potentially would need to be done by multiple
drivers which means quite a lot of duplicated code and bloat.
To avoid that we can use the observation that the core sets
dev->power.is_suspended before disabling runtime PM and use that
instead of the driver's private flag. Still, potentially many drivers
would need to repeat that same check in quite a few places, so it's
better to let the core do it.
Then we can be a bit smarter and check whether or not runtime PM was
disabled by the core only (disable_depth == 1) or by someone else in
addition to the core (disable_depth > 1). In the former case
rpm_resume() can return 1 if the runtime PM status is RPM_ACTIVE,
because it means the device was active when the core disabled runtime
PM. In the latter case it should still return -EACCES, because it
isn't clear why runtime PM has been disabled.
Tested on AM3730/Beagle-xM where a wakeup IRQ firing during the late
suspend phase triggers runtime PM activity in the I2C driver since the
wakeup IRQ is on an I2C-connected PMIC.
[rjw: Modified whitespace to follow the file's convention.]
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This patch (as1591) moves the pm_runtime_get_noresume() and
pm_runtime_put_sync() calls from __device_suspend() and
device_resume() to device_prepare() and device_complete() in the PM
core.
The reason for doing this is to make sure that parent devices remain
at full power (i.e., don't go into runtime suspend) while their
children are being resumed from a system sleep.
The PCI core already contained equivalent code to serve the same
purpose. The patch removes the duplicated code, since it is no longer
needed. One of the comments from the PCI core gets moved into the PM
core, and a second comment is added to explain whe the _get_noresume
and _put_sync calls are present.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The per-device PM QoS locking requires a spinlock to be used. The reasons
are:
- an alignement with the PM QoS core code, which is used by the per-device
PM QoS code for the constraints lists management. The PM QoS core code
uses spinlocks to protect the constraints lists,
- some drivers need to use the per-device PM QoS functionality from
interrupt context or spinlock protected context.
An example of such a driver is the OMAP HSI (high-speed synchronous serial
interface) driver which needs to control the IP block idle state
depending on the FIFO empty state, from interrupt context.
Reported-by: Djamil Elaidi <d-elaidi@ti.com>
Signed-off-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
When dpm_suspend_noirq fail, state is PMSG_SUSPEND,
should change to PMSG_RESUME when dpm_resume_early is called
Signed-off-by: Feng Hong <hongfeng@marvell.com>
Signed-off-by: Raul Xiong <xjian@marvell.com>
Signed-off-by: Neil Zhang <zhangwm@marvell.com>
Cc: stable@vger.kernel.org
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* pm-cpufreq:
cpufreq: OMAP: remove loops_per_jiffy recalculate for smp
sections: fix section conflicts in drivers/cpufreq
cpufreq: conservative: update frequency when limits are relaxed
cpufreq / ondemand: update frequency when limits are relaxed
cpufreq: Add a generic cpufreq-cpu0 driver
PM / OPP: Initialize OPP table from device tree
ARM: add cpufreq transiton notifier to adjust loops_per_jiffy for smp
cpufreq: Remove support for hardware P-state chips from powernow-k8
acpi-cpufreq: Add compatibility for legacy AMD cpb sysfs knob
acpi-cpufreq: Add support for disabling dynamic overclocking
ACPI: Add fixups for AMD P-state figures
powernow-k8: delay info messages until initialization has succeeded
cpufreq: Add warning message to powernow-k8
acpi-cpufreq: Add quirk to disable _PSD usage on all AMD CPUs
acpi-cpufreq: Add support for modern AMD CPUs
cpufreq / powernow-k8: Fixup missing _PSS objects message
PM / cpufreq: Initialise the cpu field during conservative governor start
* pm-sleep:
properly __init-annotate pm_sysrq_init()
PM / wakeup: Use irqsave/irqrestore for events_lock
PM / Freezer: Fix small typo "regrigerator"
PM / Sleep: Print name of wakeup source that aborts suspend
With a lot of devices booting from device tree nowadays, it requires
that OPP table can be initialized from device tree. The patch adds
a helper function of_init_opp_table together with a binding doc for
that purpose.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Jon Medhurst (Tixy) recently noticed a problem with the
events_lock usage. One of the Android patches that uses
wakeup_sources calls wakeup_source_add() with irqs disabled.
However, the event_lock usage in wakeup_source_add() uses
spin_lock_irq()/spin_unlock_irq(), which reenables interrupts.
This results in lockdep warnings.
The fix is to use spin_lock_irqsave()/spin_lock_irqrestore()
instead for the events_lock.
References: https://bugs.launchpad.net/linaro-landing-team-arm/+bug/1037565
Reported-and-debugged-by: Jon Medhurst (Tixy) <tixy@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
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>
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 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>
A driver or app may repeatedly request a wakeup source while the system
is attempting to enter suspend, which may indicate a bug or at least
point out a highly active system component that is responsible for
decreased battery life on a mobile device. Even when the incidence
of suspend abort is not severe, identifying wakeup sources that
frequently abort suspend can be a useful clue for power management
analysis.
In some cases the existing stats can point out the offender where there is
an unexpectedly high activation count that stands out from the others, but
in other cases the wakeup source frequently taken just after the rest of
the system thinks its time to suspend might not stand out in the overall
stats.
It is also often useful to have information about what's been happening
recently, rather than totals of all activity for the system boot.
It's suggested to dump a line about which wakeup source
aborted suspend to aid analysis of these situations.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
If __dev_pm_qos_read_value(dev) returns a negative value,
rpm_suspend() should return -EPERM for dev even if its
power.no_callbacks flag is set. For this to happen, the device's
power.no_callbacks flag has to be checked after the PM QoS check,
so move the PM QoS check to rpm_check_suspend_allowed() (this will
make it cover idle notifications as well as runtime suspend too).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
The power.deferred_resume can only be set if the runtime PM status
of device is RPM_SUSPENDING and it should be cleared after its
status has been changed, regardless of whether or not the runtime
suspend has been successful. However, it only is cleared on
suspend failure, while it may remain set on successful suspend and
is happily leaked to rpm_resume() executed in that case.
That shouldn't happen, so if power.deferred_resume is set in
rpm_suspend() after the status has been changed to RPM_SUSPENDED,
clear it before calling rpm_resume(). Then, it doesn't need to be
cleared before changing the status to RPM_SUSPENDING any more,
because it's always cleared after the status has been changed to
either RPM_SUSPENDED (on success) or RPM_ACTIVE (on failure).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
For devices whose power.no_callbacks flag is set, rpm_resume()
should return 1 if the device's parent is already active, so that
the callers of pm_runtime_get() don't think that they have to wait
for the device to resume (asynchronously) in that case (the core
won't queue up an asynchronous resume in that case, so there's
nothing to wait for anyway).
Modify the code accordingly (and make sure that an idle notification
will be queued up on success, even if 1 is to be returned).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
dpm_list and its pm lock provide a good way to iterate all
devices in system. Except this way, there is no other easy
way to iterate devices in system.
firmware loader need to cache firmware images for devices
before system sleep, so introduce the function to meet its
demand.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commits 1d5fcfec22 (PM / Domains: Add device domain data reference
counter) and 62d4490294 (PM / Domains: Allow device callbacks to be
added at any time) added checks for the return value of
dev_pm_get_subsys_data(), but those checks were incorrect, because
that function returned 1 on success in some cases.
Since all of the existing users of dev_pm_get_subsys_data() don't use
the positive value returned by it on success, change its definition
so that it always returns 0 when successful.
Reported-by: Heiko Stübner <heiko@sntech.de>
Reported-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Commit cf579dfb82 (PM / Sleep: Introduce
"late suspend" and "early resume" of devices) introduced a bug where
suspend_late handlers would be called, but if dpm_suspend_noirq returned
an error the early_resume handlers would never be called. All devices
would end up on the dpm_late_early_list, and would never be resumed
again.
Fix it by calling dpm_resume_early when dpm_suspend_noirq returns
an error.
Signed-off-by: Colin Cross <ccross@android.com>
Cc: stable@vger.kernel.org
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* pm-sleep:
PM / Sleep: Require CAP_BLOCK_SUSPEND to use wake_lock/wake_unlock
PM / Sleep: Add missing static storage class specifiers in main.c
PM / Sleep: Fix build warning in sysfs.c for CONFIG_PM_SLEEP unset
PM / Hibernate: Print hibernation/thaw progress indicator one line at a time.
PM / Sleep: Separate printing suspend times from initcall_debug
PM / Sleep: add knob for printing device resume times
ftrace: Disable function tracing during suspend/resume and hibernation, again
PM / Hibernate: Enable suspend to both for in-kernel hibernation.
* pm-domains:
PM / Domains: Fix build warning for CONFIG_PM_RUNTIME unset
PM / Domains: Replace plain integer with NULL pointer in domain.c file
PM / Domains: Add missing static storage class specifier in domain.c file
PM / Domains: Allow device callbacks to be added at any time
PM / Domains: Add device domain data reference counter
PM / Domains: Add preliminary support for cpuidle, v2
PM / Domains: Do not stop devices after restoring their states
PM / Domains: Use subsystem runtime suspend/resume callbacks by default
Fix the following sparse warning:
drivers/base/power/qos.c:465:29: 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>
Fix the following sparse warnings:
drivers/base/power/main.c:48:1: warning: symbol 'dpm_prepared_list' was not declared. Should it be static?
drivers/base/power/main.c:49:1: warning: symbol 'dpm_suspended_list' was not declared. Should it be static?
drivers/base/power/main.c:50:1: warning: symbol 'dpm_late_early_list' was not declared. Should it be static?
drivers/base/power/main.c:51:1: warning: symbol 'dpm_noirq_list' 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>
The power/async device sysfs attribute is only used if both
CONFIG_PM_ADVANCED_DEBUG and CONFIG_PM_SLEEP are set, but the code
implementing it doesn't depend on CONFIG_PM_SLEEP. As a result, a
build warning appears if CONFIG_PM_ADVANCED_DEBUG is set and
CONFIG_PM_SLEEP is not set.
Fix it by adding a #ifdef CONFIG_PM_SLEEP around the code in
question.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
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>
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>
On certain bios, resume hangs if cpus are allowed to enter idle states
during suspend [1].
This was fixed in apci idle driver [2].But intel_idle driver does not
have this fix. Thus instead of replicating the fix in both the idle
drivers, or in more platform specific idle drivers if needed, the
more general cpuidle infrastructure could handle this.
A suspend callback in cpuidle_driver could handle this fix. But
a cpuidle_driver provides only basic functionalities like platform idle
state detection capability and mechanisms to support entry and exit
into CPU idle states. All other cpuidle functions are found in the
cpuidle generic infrastructure for good reason that all cpuidle
drivers, irrepective of their platforms will support these functions.
One option therefore would be to register a suspend callback in cpuidle
which handles this fix. This could be called through a PM_SUSPEND_PREPARE
notifier. But this is too generic a notfier for a driver to handle.
Also, ideally the job of cpuidle is not to handle side effects of suspend.
It should expose the interfaces which "handle cpuidle 'during' suspend"
or any other operation, which the subsystems call during that respective
operation.
The fix demands that during suspend, no cpus should be allowed to enter
deep C-states. The interface cpuidle_uninstall_idle_handler() in cpuidle
ensures that. Not just that it also kicks all the cpus which are already
in idle out of their idle states which was being done during cpu hotplug
through a CPU_DYING_FROZEN callbacks.
Now the question arises about when during suspend should
cpuidle_uninstall_idle_handler() be called. Since we are dealing with
drivers it seems best to call this function during dpm_suspend().
Delaying the call till dpm_suspend_noirq() does no harm, as long as it is
before cpu_hotplug_begin() to avoid race conditions with cpu hotpulg
operations. In dpm_suspend_noirq(), it would be wise to place this call
before suspend_device_irqs() to avoid ugly interactions with the same.
Ananlogously, during resume.
References:
[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/674075.
[2] http://marc.info/?l=linux-pm&m=133958534231884&w=2
Reported-and-tested-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
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>
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>
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>
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>
Change the behavior of the newly introduced
/sys/power/pm_print_times attribute so that its initial value
depends on initcall_debug, but setting it to 0 will cause device
suspend/resume times not to be printed, even if initcall_debug has
been set. This way, the people who use initcall_debug for reasons
other than PM debugging will be able to switch the suspend/resume
times printing off, if need be.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Added a new knob called /sys/power/pm_print_times. Setting it to 1
enables printing of time taken by devices to suspend and resume.
Setting it to 0 disables this printing (unless overridden by
initcall_debug kernel command line option).
Signed-off-by: Sameer Nanda <snanda@chromium.org>
Acked-by: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
__device_suspend() must always send a completion. Otherwise, parent
devices will wait forever.
Commit 1e2ef05b, "PM: Limit race conditions between runtime PM and
system sleep (v2)", introduced a regression by short-circuiting the
complete_all() for certain error cases.
This patch fixes the bug by always signalling a completion.
Addresses http://crosbug.com/31972
Tested by injecting an abort.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
* pm-sleep:
PM / Sleep: User space wakeup sources garbage collector Kconfig option
PM / Sleep: Make the limit of user space wakeup sources configurable
PM / Documentation: suspend-and-cpuhotplug.txt: Fix typo
PM / Sleep: Fix a mistake in a conditional in autosleep_store()
epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready
PM / Sleep: Add user space interface for manipulating wakeup sources, v3
PM / Sleep: Add "prevent autosleep time" statistics to wakeup sources
PM / Sleep: Implement opportunistic sleep, v2
PM / Sleep: Add wakeup_source_activate and wakeup_source_deactivate tracepoints
PM / Sleep: Change wakeup source statistics to follow Android
PM / Sleep: Use wait queue to signal "no wakeup events in progress"
PM / Sleep: Look for wakeup events in later stages of device suspend
PM / Hibernate: Hibernate/thaw fixes/improvements
The default domain power off governor function for generic PM
domains, default_power_down_ok(), may violate subdomain maximum
off time limit by allowing the master domain to be off for too
long. Namely, it only finds the minium of all device maximum
off times over the domain's devices and uses that to compute the
domain's maximum off time, but it should do the same for the
subdomains.
Fix this problem by modifying default_power_down_ok() to compute
the given domain's maximum off time as the difference between the
minimum off time over all devices and subdomains in the domain and
its power on latency.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
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>
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>
The current behavior of dev_pm_qos_add_notifier() makes device PM QoS
notifiers less than useful. Namely, it silently returns success when
called before any PM QoS constraints are added for the device, so the
caller will assume that the notifier has been registered, but when
someone actually adds some nontrivial constraints for the device
eventually, the previous callers of dev_pm_qos_add_notifier()
will not know about that and their notifier routines will not be
executed (contrary to their expectations).
To address this problem make dev_pm_qos_add_notifier() create the
constraints object for the device if it is not present when the
routine is called.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by : markgross <markgross@thegnar.org>
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>
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>
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>
Android allows user space to manipulate wakelocks using two
sysfs file located in /sys/power/, wake_lock and wake_unlock.
Writing a wakelock name and optionally a timeout to the wake_lock
file causes the wakelock whose name was written to be acquired (it
is created before is necessary), optionally with the given timeout.
Writing the name of a wakelock to wake_unlock causes that wakelock
to be released.
Implement an analogous interface for user space using wakeup sources.
Add the /sys/power/wake_lock and /sys/power/wake_unlock files
allowing user space to create, activate and deactivate wakeup
sources, such that writing a name and optionally a timeout to
wake_lock causes the wakeup source of that name to be activated,
optionally with the given timeout. If that wakeup source doesn't
exist, it will be created and then activated. Writing a name to
wake_unlock causes the wakeup source of that name, if there is one,
to be deactivated. Wakeup sources created with the help of
wake_lock that haven't been used for more than 5 minutes are garbage
collected and destroyed. Moreover, there can be only WL_NUMBER_LIMIT
wakeup sources created with the help of wake_lock present at a time.
The data type used to track wakeup sources created by user space is
called "struct wakelock" to indicate the origins of this feature.
This version of the patch includes an rbtree manipulation fix from John Stultz.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Android uses one wakelock statistics that is only necessary for
opportunistic sleep. Namely, the prevent_suspend_time field
accumulates the total time the given wakelock has been locked
while "automatic suspend" was enabled. Add an analogous field,
prevent_sleep_time, to wakeup sources and make it behave in a similar
way.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce a mechanism by which the kernel can trigger global
transitions to a sleep state chosen by user space if there are no
active wakeup sources.
It consists of a new sysfs attribute, /sys/power/autosleep, that
can be written one of the strings returned by reads from
/sys/power/state, an ordered workqueue and a work item carrying out
the "suspend" operations. If a string representing the system's
sleep state is written to /sys/power/autosleep, the work item
triggering transitions to that state is queued up and it requeues
itself after every execution until user space writes "off" to
/sys/power/autosleep.
That work item enables the detection of wakeup events using the
functions already defined in drivers/base/power/wakeup.c (with one
small modification) and calls either pm_suspend(), or hibernate() to
put the system into a sleep state. If a wakeup event is reported
while the transition is in progress, it will abort the transition and
the "system suspend" work item will be queued up again.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Add tracepoints to wakeup_source_activate and wakeup_source_deactivate.
Useful for checking that specific wakeup sources overlap as expected.
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Wakeup statistics used by Android are slightly different from what we
have in wakeup sources at the moment and there aren't any known
users of those statistics other than Android, so modify them to make
it easier for Android to switch to wakeup sources.
This removes the struct wakeup_source's hit_cout field, which is very
rough and therefore not very useful, and adds two new fields,
wakeup_count and expire_count. The first one tracks how many times
the wakeup source is activated with events_check_enabled set (which
roughly corresponds to the situations when a system power transition
to a sleep state is in progress and would be aborted by this wakeup
source if it were the only active one at that time) and the second
one is the number of times the wakeup source has been activated with
a timeout that expired.
Additionally, the last_time field is now updated when the wakeup
source is deactivated too (previously it was only updated during
the wakeup source's activation), which seems to be what Android does
with the analogous counter for wakelocks.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current wakeup source deactivation code doesn't do anything when
the counter of wakeup events in progress goes down to zero, which
requires pm_get_wakeup_count() to poll that counter periodically.
Although this reduces the average time it takes to deactivate a
wakeup source, it also may lead to a substantial amount of unnecessary
polling if there are extended periods of wakeup activity. Thus it
seems reasonable to use a wait queue for signaling the "no wakeup
events in progress" condition and remove the polling.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: mark gross <markgross@thegnar.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the device suspend code in drivers/base/power/main.c
only checks if there have been any wakeup events, and therefore the
ongoing system transition to a sleep state should be aborted, during
the first (i.e. "suspend") device suspend phase. However, wakeup
events may be reported later as well, so it's reasonable to look for
them in the in the subsequent (i.e. "late suspend" and "suspend
noirq") phases.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch (as1535) fixes a bug in the runtime PM core. When a
runtime suspend attempt completes, whether successfully or not, the
device's power.wait_queue is supposed to be signalled. But this
doesn't happen in the failure pathway of rpm_suspend() when another
autosuspend attempt is rescheduled. As a result, a task can get stuck
indefinitely on the wait queue (I have seen this happen in testing).
The patch fixes the problem by moving the wake_up_all() call up near
the start of the failure code.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
"[RFC PATCH 0/2] audit of linux/device.h users in include/*"
https://lkml.org/lkml/2012/3/4/159
--
Nearly every subsystem has some kind of header with a proto like:
void foo(struct device *dev);
and yet there is no reason for most of these guys to care about the
sub fields within the device struct. This allows us to significantly
reduce the scope of headers including headers. For this instance, a
reduction of about 40% is achieved by replacing the include with the
simple fact that the device is some kind of a struct.
Unlike the much larger module.h cleanup, this one is simply two
commits. One to fix the implicit <linux/device.h> users, and then
one to delete the device.h includes from the linux/include/ dir
wherever possible.
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Merge tag 'device-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
Pull <linux/device.h> avoidance patches from Paul Gortmaker:
"Nearly every subsystem has some kind of header with a proto like:
void foo(struct device *dev);
and yet there is no reason for most of these guys to care about the
sub fields within the device struct. This allows us to significantly
reduce the scope of headers including headers. For this instance, a
reduction of about 40% is achieved by replacing the include with the
simple fact that the device is some kind of a struct.
Unlike the much larger module.h cleanup, this one is simply two
commits. One to fix the implicit <linux/device.h> users, and then one
to delete the device.h includes from the linux/include/ dir wherever
possible."
* tag 'device-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
device.h: audit and cleanup users in main include dir
device.h: cleanup users outside of linux/include (C files)
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>
* pm-domains:
PM / shmobile: Make MTU2 driver use pm_genpd_dev_always_on()
PM / shmobile: Make CMT driver use pm_genpd_dev_always_on()
PM / shmobile: Make TMU driver use pm_genpd_dev_always_on()
PM / Domains: Introduce "always on" device flag
PM / Domains: Fix hibernation restore of devices, v2
PM / Domains: Fix handling of wakeup devices during system resume
* pm-qos:
sh_mmcif / PM: Use PM QoS latency constraint
tmio_mmc / PM: Use PM QoS latency constraint
PM / QoS: Make it possible to expose PM QoS latency constraints
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
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
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
A runtime suspend of a device (e.g. an MMC controller) belonging to
a power domain or, in a more complicated scenario, a runtime suspend
of another device in the same power domain, may cause power to be
removed from the entire domain. In that case, the amount of time
necessary to runtime-resume the given device (e.g. the MMC
controller) is often substantially greater than the time needed to
run its driver's runtime resume callback. That may hurt performance
in some situations, because user data may need to wait for the
device to become operational, so we should make it possible to
prevent that from happening.
For this reason, introduce a new sysfs attribute for devices,
power/pm_qos_resume_latency_us, allowing user space to specify the
upper bound of the time necessary to bring the (runtime-suspended)
device up after the resume of it has been requested. However, make
that attribute appear only for the devices whose drivers declare
support for it by calling the (new) dev_pm_qos_expose_latency_limit()
helper function with the appropriate initial value of the attribute.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
For files that are actively using linux/device.h, make sure
that they call it out. This will allow us to clean up some
of the implicit uses of linux/device.h within include/*
without introducing build regressions.
Yes, this was created by "cheating" -- i.e. the headers were
cleaned up, and then the fallout was found and fixed, and then
the two commits were reordered. This ensures we don't introduce
build regressions into the git history.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* pm-domains:
PM / Domains: Fix include for PM_GENERIC_DOMAINS=n case
PM / Domains: Provide a dummy dev_gpd_data() when generic domains are not used
PM / Domains: Run late/early device suspend callbacks at the right time
ARM: EXYNOS: Hook up power domains to generic power domain infrastructure
PM / Domains: Add OF support
The existing wakeup source initialization routines are not
particularly useful for wakeup sources that aren't created by
wakeup_source_create(), because their users have to open code
filling the objects with zeros and setting their names. For this
reason, introduce routines that can be used for initializing, for
example, static wakeup source objects.
Requested-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
If __pm_stay_awake() is called after __pm_wakeup_event() for the same
wakep source object before its timer expires, it won't cancel the
timer, so the wakeup source will be deactivated from the timer
function as scheduled by __pm_wakeup_event(). In that case
__pm_stay_awake() doesn't have any effect beyond incrementing
the wakeup source's event_count field, although it should cancel
the timer and make the wakeup source stay active until __pm_relax()
is called for it.
To fix this problem make __pm_stay_awake() delete the wakeup source's
timer and ensure that it won't be deactivated from the timer funtion
afterwards by clearing its timer_expires field.
Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
If __pm_wakeup_event() has been used (with a nonzero timeout) to
report a wakeup event and then __pm_relax() immediately followed by
__pm_stay_awake() is called or __pm_wakeup_event() is called once
again for the same wakeup source object before its timer expires, the
timer function pm_wakeup_timer_fn() may still be run as a result of
the previous __pm_wakeup_event() call. In either of those cases it
may mistakenly deactivate the wakeup source that has just been
activated.
To prevent that from happening, make wakeup_source_deactivate()
clear the wakeup source's timer_expires field and make
pm_wakeup_timer_fn() check if timer_expires is different from zero
and if it's not in future before calling wakeup_source_deactivate()
(if timer_expires is 0, it means that the timer has just been
deleted and if timer_expires is in future, it means that the timer
has just been rescheduled to a different time).
Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
If wakeup_source_destroy() is called for an active wakeup source that
is never deactivated, it will spin forever. To prevent that from
happening, make wakeup_source_destroy() call __pm_relax() for the
wakeup source object it is about to free instead of waiting until
it will be deactivated by someone else. However, for this to work
it also needs to make sure that the timer function will not be
executed after the final __pm_relax(), so make it run
del_timer_sync() on the wakeup source's timer beforehand.
Additionally, update the kerneldoc comment to document the
requirement that __pm_stay_awake() and __pm_wakeup_event() must not
be run in parallel with wakeup_source_destroy().
Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Initialize wakeup source locks in wakeup_source_add() instead of
wakeup_source_create(), because otherwise the locks of the wakeup
sources that haven't been allocated with wakeup_source_create()
aren't initialized and handled properly.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* '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
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>
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>
The current device suspend/resume phases during system-wide power
transitions appear to be insufficient for some platforms that want
to use the same callback routines for saving device states and
related operations during runtime suspend/resume as well as during
system suspend/resume. In principle, they could point their
.suspend_noirq() and .resume_noirq() to the same callback routines
as their .runtime_suspend() and .runtime_resume(), respectively,
but at least some of them require device interrupts to be enabled
while the code in those routines is running.
It also makes sense to have device suspend-resume callbacks that will
be executed with runtime PM disabled and with device interrupts
enabled in case someone needs to run some special code in that
context during system-wide power transitions.
Apart from this, .suspend_noirq() and .resume_noirq() were introduced
as a workaround for drivers using shared interrupts and failing to
prevent their interrupt handlers from accessing suspended hardware.
It appears to be better not to use them for other porposes, or we may
have to deal with some serious confusion (which seems to be happening
already).
For the above reasons, introduce new device suspend/resume phases,
"late suspend" and "early resume" (and analogously for hibernation)
whose callback will be executed with runtime PM disabled and with
device interrupts enabled and whose callback pointers generally may
point to runtime suspend/resume routines.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
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>
The governor functions in drivers/base/power/domain_governor.c
are only used if CONFIG_PM_RUNTIME is set and they refer to data
structures that are only present in that case. For this reason,
they shouldn't be compiled at all when CONFIG_PM_RUNTIME is not set.
Reported-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
* pm-domains:
PM / shmobile: Allow the A4R domain to be turned off at run time
PM / input / touchscreen: Make st1232 use device PM QoS constraints
PM / QoS: Introduce dev_pm_qos_add_ancestor_request()
PM / shmobile: Remove the stay_on flag from SH7372's PM domains
PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume
PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode
ARM: S3C64XX: Implement basic power domain support
PM / shmobile: Use common always on power domain governor
PM / Domains: Provide an always on power domain governor
PM / Domains: Fix default system suspend/resume operations
PM / Domains: Make it possible to assign names to generic PM domains
PM / Domains: fix compilation failure for CONFIG_PM_GENERIC_DOMAINS unset
PM / Domains: Automatically update overoptimistic latency information
PM / Domains: Add default power off governor function (v4)
PM / Domains: Add device stop governor function (v4)
PM / Domains: Rework system suspend callback routines (v2)
PM / Domains: Introduce "save/restore state" device callbacks
PM / Domains: Make it possible to use per-device domain callbacks
Some devices, like the I2C controller on SH7372, are not
necessary for providing power to their children or forwarding
wakeup signals (and generally interrupts) from them. They are
only needed by their children when there's some data to transfer,
so they may be suspended for the majority of time and resumed
on demand, when the children have data to send or receive. For this
purpose, however, their power.ignore_children flags have to be set,
or the PM core wouldn't allow them to be suspended while their
children were active.
Unfortunately, in some situations it may take too much time to
resume such devices so that they can assist their children in
transferring data. For example, if such a device belongs to a PM
domain which goes to the "power off" state when that device is
suspended, it may take too much time to restore power to the
domain in response to the request from one of the device's
children. In that case, if the parent's resume time is critical,
the domain should stay in the "power on" state, although it still may
be desirable to power manage the parent itself (e.g. by manipulating
its clock).
In general, device PM QoS may be used to address this problem.
Namely, if the device's children added PM QoS latency constraints
for it, they would be able to prevent it from being put into an
overly deep low-power state. However, in some cases the devices
needing to be serviced are not the immediate children of a
"children-ignoring" device, but its grandchildren or even less
direct descendants. In those cases, the entity wanting to add a
PM QoS request for a given device's ancestor that ignores its
children will have to find it in the first place, so introduce a new
helper function that may be used to achieve that. This function,
dev_pm_qos_add_ancestor_request(), will search for the first
ancestor of the given device whose power.ignore_children flag is
set and will add a device PM QoS latency request for that ancestor
on behalf of the caller. The request added this way may be removed
with the help of dev_pm_qos_remove_request() in the future, like
any other device PM QoS latency request.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
Make the PM core execute driver PM callbacks directly if the
corresponding subsystem callbacks are not present.
There are three reasons for doing that. First, it reflects the
behavior of drivers/base/dd.c:really_probe() that runs the driver's
.probe() callback directly if the bus type's one is not defined, so
this change will remove one arbitrary difference between the PM core
and the remaining parts of the driver core. Second, it will allow
some subsystems, whose PM callbacks don't do anything except for
executing driver callbacks, to be simplified quite a bit by removing
those "forward-only" callbacks. Finally, it will allow us to remove
one level of indirection in the system suspend and resume code paths
where it is not necessary, which is going to lead to less debug noise
with initcall_debug passed in the kernel command line (messages won't
be printed for driverless devices whose subsystems don't provide
PM callbacks among other things).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Make the pm_op() and pm_noirq_op() functions return pointers to
appropriate callbacks instead of executing those callbacks and
returning their results.
This change is required for a subsequent modification that will
execute the corresponding driver callback if the subsystem
callback returned by either pm_op(), or pm_noirq_op() is NULL.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
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>
Since systems are likely to have power domains that can't be turned off
for various reasons at least temporarily while implementing power domain
support provide a default governor which will always refuse to power off
the domain, saving platforms having to implement their own.
Since the code is so tiny don't bother with a Kconfig symbol for it.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
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>
Make pm_op() and pm_noirq_op() use the same helper function for
running callbacks, which will cause them to use the same format of
diagnostic messages. This also reduces the complexity and size of
the code quite a bit.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
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>
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>
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>
Make the runtime PM core use device PM QoS constraints to check if
it is allowed to suspend a given device, so that an error code is
returned if the device's own PM QoS constraint is negative or one of
its children has already been suspended for too long. If this is
not the case, the maximum estimated time the device is allowed to be
suspended, computed as the minimum of the device's PM QoS constraint
and the PM QoS constraints of its children (reduced by the difference
between the current time and their suspend times) is stored in a new
device's PM field power.max_time_suspended_ns that can be used by
the device's subsystem or PM domain to decide whether or not to put
the device into lower-power (and presumably higher-latency) states
later (if the constraint is 0, which means "no constraint", the
power.max_time_suspended_ns is set to -1).
Additionally, the time of execution of the subsystem-level
.runtime_suspend() callback for the device is recorded in the new
power.suspend_time field for later use by the device's subsystem or
PM domain along with power.max_time_suspended_ns (it also is used
by the core code when the device's parent is suspended).
Introduce a new helper function,
pm_runtime_update_max_time_suspended(), allowing subsystems and PM
domains (or device drivers) to update the power.max_time_suspended_ns
field, for example after changing the power state of a suspended
device.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Remove a few if () and return statements in device_suspend_noirq()
that aren't really necessary.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
The "End" label in device_prepare() in drivers/base/power/main.c is
not necessary and the jumps to it have no real effect, so remove them
all.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Commit 4ca46ff3e0 (PM / Sleep: Mark
devices involved in wakeup signaling during suspend) introduced
the power.wakeup_path field in struct dev_pm_info to mark devices
whose children are enabled to wake up the system from sleep states,
so that power domains containing the parents that provide their
children with wakeup power and/or relay their wakeup signals are not
turned off. Unfortunately, that introduced a PM regression on SH7372
whose power consumption in the system "memory sleep" state increased
as a result of it, because it prevented the power domain containing
the I2C controller from being turned off when some children of that
controller were enabled to wake up the system, although the
controller was not necessary for them to signal wakeup.
To fix this issue use the observation that devices whose
power.ignore_children flag is set for runtime PM should be treated
analogously during system suspend. Namely, they shouldn't be
included in wakeup paths going through their children. Since the
SH7372 I2C controller's power.ignore_children flag is set, doing so
will restore the previous behavior of that SOC.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Make dev_pm_qos_add_request() use WARN() in a better way and do not hardcode
the function's name into the message (use __func__ instead).
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Refrain from running clk_disable() on clocks that
have not been enabled. A typical case when this can
happen is during Suspend-to-RAM for devices that have
no driver associated with them. In such case the clock
may be in default ACQUIRED state.
Without this patch the sh7372 Mackerel board crashes
in __clk_disable() during Suspend-to-RAM with:
"Trying to disable clock 0xdeadbeef with 0 usecount"
This happens for the CEU device which is added during
boot. The test case has no CEU driver included in the
kernel configuration. Needed for v3.2-rc1.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Use ERR_CAST inlined function instead of ERR_PTR(PTR_ERR(...))
[The semantic patch that makes this change is available
in scripts/coccinelle/api/err_cast.cocci.
More information about semantic patching is available at
http://coccinelle.lip6.fr/]
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
Originally, the runtime PM core would send an idle notification
whenever a suspend attempt failed. The idle callback routine could
then schedule a delayed suspend for some time later.
However this behavior was changed by commit
f71648d73c (PM / Runtime: Remove idle
notification after failing suspend). No notifications were sent, and
there was no clear mechanism to retry failed suspends.
This caused problems for the usbhid driver, because it fails
autosuspend attempts as long as a key is being held down. Therefore
this patch (as1492) adds a mechanism for retrying failed
autosuspends. If the callback routine updates the last_busy field so
that the next autosuspend expiration time is in the future, the
autosuspend will automatically be rescheduled.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Henrik Rydberg <rydberg@euromail.se>
Cc: <stable@kernel.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
With delta type being int, its value is made zero
for all values of now > 0x80000000.
Hence fixing it.
Signed-off-by: venu byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This file isn't using full modular functionality, and hence
can be "downgraded" to just using export.h
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
Since kfree() checks it its argument is not NULL, it is not necessary
to duplicate this check in __pm_clk_remove().
[rjw: Added the changelog.]
Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* pm-domains:
ARM: mach-shmobile: sh7372 A4R support (v4)
ARM: mach-shmobile: sh7372 A3SP support (v4)
PM / Sleep: Mark devices involved in wakeup signaling during suspend
The generic PM domains code in drivers/base/power/domain.c has
to avoid powering off domains that provide power to wakeup devices
during system suspend. Currently, however, this only works for
wakeup devices directly belonging to the given domain and not for
their children (or the children of their children and so on).
Thus, if there's a wakeup device whose parent belongs to a power
domain handled by the generic PM domains code, the domain will be
powered off during system suspend preventing the device from
signaling wakeup.
To address this problem introduce a device flag, power.wakeup_path,
that will be set during system suspend for all wakeup devices,
their parents, the parents of their parents and so on. This way,
all wakeup paths in the device hierarchy will be marked and the
generic PM domains code will only need to avoid powering off
domains containing devices whose power.wakeup_path is set.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This patch (as1485) documents a change to the kernel's default wakeup
policy. Devices that forward wakeup requests between buses should be
enabled for wakeup by default.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Record S3 failure time about each reason and the latest two failed
devices' names in S3 progress.
We can check it through 'suspend_stats' entry in debugfs.
The motivation of the patch:
We are enabling power features on Medfield. Comparing with PC/notebook,
a mobile enters/exits suspend-2-ram (we call it s3 on Medfield) far
more frequently. If it can't enter suspend-2-ram in time, the power
might be used up soon.
We often find sometimes, a device suspend fails. Then, system retries
s3 over and over again. As display is off, testers and developers
don't know what happens.
Some testers and developers complain they don't know if system
tries suspend-2-ram, and what device fails to suspend. They need
such info for a quick check. The patch adds suspend_stats under
debugfs for users to check suspend to RAM statistics quickly.
If not using this patch, we have other methods to get info about
what device fails. One is to turn on CONFIG_PM_DEBUG, but users
would get too much info and testers need recompile the system.
In addition, dynamic debug is another good tool to dump debug info.
But it still doesn't match our utilization scenario closely.
1) user need write a user space parser to process the syslog output;
2) Our testing scenario is we leave the mobile for at least hours.
Then, check its status. No serial console available during the
testing. One is because console would be suspended, and the other
is serial console connecting with spi or HSU devices would consume
power. These devices are powered off at suspend-2-ram.
Signed-off-by: ShuoX Liu <shuox.liu@intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
If .runtime_suspend() returns -EAGAIN or -EBUSY, the device should
still be in ACTIVE state, so it is not necessary to send an idle
notification to its parent. If .runtime_suspend() returns other
fatal failure, it doesn't make sense to send idle notification to
its parent.
Skip parent idle notification when failure is returned from
.runtime_suspend() and update comments in rpm_suspend() to reflect
that change.
[rjw: Modified the subject and changelog slightly.]
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This patch fix kerneldoc comments for rpm_suspend():
- 'Cancel a pending idle notification' should be put before, also
should be changed to 'Cancel a pending idle notification,
autosuspend or suspend'.
- idle notification for the device after succeeding suspend has
been removed, so update the comment accordingly.
[rjw: Modified the subject and changelog slightly.]
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* pm-domains:
PM / Domains: Split device PM domain data into base and need_restore
ARM: mach-shmobile: sh7372 sleep warning fixes
ARM: mach-shmobile: sh7372 A3SM support
ARM: mach-shmobile: sh7372 generic suspend/resume support
PM / Domains: Preliminary support for devices with power.irq_safe set
PM: Move clock-related definitions and headers to separate file
PM / Domains: Use power.sybsys_data to reduce overhead
PM: Reference counting of power.subsys_data
PM: Introduce struct pm_subsys_data
ARM / shmobile: Make A3RV be a subdomain of A4LC on SH7372
PM / Domains: Rename argument of pm_genpd_add_subdomain()
PM / Domains: Rename GPD_STATE_WAIT_PARENT to GPD_STATE_WAIT_MASTER
PM / Domains: Allow generic PM domains to have multiple masters
PM / Domains: Add "wait for parent" status for generic PM domains
PM / Domains: Make pm_genpd_poweron() always survive parent removal
PM / Domains: Do not take parent locks to modify subdomain counters
PM / Domains: Implement subdomain counters as atomic fields
* pm-runtime:
PM / Tracing: build rpm-traces.c only if CONFIG_PM_RUNTIME is set
PM / Runtime: Replace dev_dbg() with trace_rpm_*()
PM / Runtime: Introduce trace points for tracing rpm_* functions
PM / Runtime: Don't run callbacks under lock for power.irq_safe set
USB: Add wakeup info to debugging messages
PM / Runtime: pm_runtime_idle() can be called in atomic context
PM / Runtime: Add macro to test for runtime PM events
PM / Runtime: Add might_sleep() to runtime PM functions
To read the current PM QoS value for a given device we need to
make sure that the device's power.constraints object won't be
removed while we're doing that. For this reason, put the
operation under dev->power.lock and acquire the lock
around the initialization and removal of power.constraints.
Moreover, since we're using the value of power.constraints to
determine whether or not the object is present, the
power.constraints_state field isn't necessary any more and may be
removed. However, dev_pm_qos_add_request() needs to check if the
device is being removed from the system before allocating a new
PM QoS constraints object for it, so make it use the
power.power_state field of struct device for this purpose.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The patch enables to register notifier_block for an OPP-device in order
to get notified for any changes in the availability of OPPs of the
device. For example, if a new OPP is inserted or enable/disable status
of an OPP is changed, the notifier is executed.
This enables the usage of opp_add, opp_enable, and opp_disable to
directly take effect with any connected entities such as cpufreq or
devfreq.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Mike Turquette <mturquette@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This patch replaces dev_dbg with trace_rpm_* inside
the three important functions:
rpm_idle
rpm_suspend
rpm_resume
Trace points have the below advantages compared with dev_dbg:
- trace points include much runtime information(such as
running cpu, current task, ...)
- most of linux distributions may disable "verbose debug"
driver debug compile switch, so it is very difficult to
report/debug runtime pm related problems from distribution
users without this kind of debug information.
- for upstream kernel users, enableing the debug switch will
produce many useless "rpm_resume" output, and it is very noise.
- dev_dbg inside rpm_suspend/rpm_resume may have some effects
on runtime pm behaviour of console devicer
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The rpm_suspend() and rpm_resume() routines execute subsystem or PM
domain callbacks under power.lock if power.irq_safe is set for the
given device. This is inconsistent with that rpm_idle() does after
commit 02b2677 (PM / Runtime: Allow _put_sync() from
interrupts-disabled context) and is problematic for subsystems and PM
domains wanting to use power.lock for synchronization in their
runtime PM callbacks.
This change requires the code checking if the device's runtime PM
status is RPM_SUSPENDING or RPM_RESUMING to be modified too, to take
the power.irq_safe set case into account (that code wasn't reachable
before with power.irq_safe set, because it's executed with the
device's power.lock held).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
The struct pm_domain_data data type is defined in such a way that
adding new fields specific to the generic PM domains code will
require include/linux/pm.h to be modified. As a result, data types
used only by the generic PM domains code will be defined in two
headers, although they all should be defined in pm_domain.h and
pm.h will need to include more headers, which won't be very nice.
For this reason change the definition of struct pm_subsys_data
so that its domain_data member is a pointer, which will allow
struct pm_domain_data to be subclassed by various PM domains
implementations. Remove the need_restore member from
struct pm_domain_data and make the generic PM domains code
subclass it by adding the need_restore member to the new data type.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Merge commit e8b364b88c
(PM / Clocks: Do not acquire a mutex under a spinlock) fixing
a regression in drivers/base/power/clock_ops.c.
Conflicts:
drivers/base/power/clock_ops.c
Commit b7ab83e (PM: Use spinlock instead of mutex in clock
management functions) introduced a regression causing clocks_mutex
to be acquired under a spinlock. This happens because
pm_clk_suspend() and pm_clk_resume() call pm_clk_acquire() under
pcd->lock, but pm_clk_acquire() executes clk_get() which causes
clocks_mutex to be acquired. Similarly, __pm_clk_remove(),
executed under pcd->lock, calls clk_put(), which also causes
clocks_mutex to be acquired.
To fix those problems make pm_clk_add() call pm_clk_acquire(), so
that pm_clk_suspend() and pm_clk_resume() don't have to do that.
Change pm_clk_remove() and pm_clk_destroy() to separate
modifications of the pcd->clock_list list from the actual removal of
PM clock entry objects done by __pm_clk_remove().
Reported-and-tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
The generic PM domains framework currently doesn't work with devices
whose power.irq_safe flag is set, because runtime PM callbacks for
such devices are run with interrupts disabled and the callbacks
provided by the generic PM domains framework use domain mutexes
and may sleep. However, such devices very well may belong to
power domains on some systems, so the generic PM domains framework
should take them into account.
For this reason, modify the generic PM domains framework so that the
domain .power_off() and .power_on() callbacks are never executed for
a domain containing devices with power.irq_safe set, although the
.stop_device() and .start_device() callbacks are still run for them.
Additionally, introduce a flag allowing the creator of a
struct generic_pm_domain object to indicate that its .stop_device()
and .start_device() callbacks may be run in interrupt context
(might_sleep_if() triggers if that flag is not set and one of those
callbacks is run in interrupt context).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Add a global notification chain that gets called upon changes to the
aggregated constraint value for any device.
The notification callbacks are passing the full constraint request data
in order for the callees to have access to it. The current use is for the
platform low-level code to access the target device of the constraint.
Signed-off-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Implement the per-device PM QoS constraints by creating a device
PM QoS API, which calls the PM QoS constraints management core code.
The per-device latency constraints data strctures are stored
in the device dev_pm_info struct.
The device PM code calls the init and destroy of the per-device constraints
data struct in order to support the dynamic insertion and removal of the
devices in the system.
To minimize the data usage by the per-device constraints, the data struct
is only allocated at the first call to dev_pm_qos_add_request.
The data is later free'd when the device is removed from the system.
A global mutex protects the constraints users from the data being
allocated and free'd.
Signed-off-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Since the PM clock management code in drivers/base/power/clock_ops.c
is used for both runtime PM and system suspend/hibernation, the
definitions of data structures and headers related to it should not
be located in include/linux/pm_rumtime.h. Move them to a separate
header file.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Currently pm_genpd_runtime_resume() has to walk the list of devices
from the device's PM domain to find the corresponding device list
object containing the need_restore field to check if the driver's
.runtime_resume() callback should be executed for the device.
This is suboptimal and can be simplified by using power.sybsys_data
to store device information used by the generic PM domains code.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Since the power.subsys_data device field will be used by multiple
filesystems, introduce a reference counting mechanism for it to avoid
freeing it prematurely or changing its value at a wrong time.
Make the PM clocks management code that currently is the only user of
power.subsys_data use the new reference counting.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Introduce struct pm_subsys_data that may be subclassed by subsystems
to store subsystem-specific information related to the device. Move
the clock management fields accessed through the power.subsys_data
pointer in struct device to the new strucutre.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Change the name of the second argument of pm_genpd_add_subdomain()
so that it is (a) shorter and (b) in agreement with the name of
the second argument of pm_genpd_add_subdomain().
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Since it is now possible for a PM domain to have multiple masters
instead of one parent, rename the "wait for parent" status to reflect
the new situation.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Currently, for a given generic PM domain there may be only one parent
domain (i.e. a PM domain it depends on). However, there is at least
one real-life case in which there should be two parents (masters) for
one PM domain (the A3RV domain on SH7372 turns out to depend on the
A4LC domain and it depends on the A4R domain and the same time). For
this reason, allow a PM domain to have multiple parents (masters) by
introducing objects representing links between PM domains.
The (logical) links between PM domains represent relationships in
which one domain is a master (i.e. it is depended on) and another
domain is a slave (i.e. it depends on the master) with the rule that
the slave cannot be powered on if the master is not powered on and
the master cannot be powered off if the slave is not powered off.
Each struct generic_pm_domain object representing a PM domain has
two lists of links, a list of links in which it is a master and
a list of links in which it is a slave. The first of these lists
replaces the list of subdomains and the second one is used in place
of the parent pointer.
Each link is represented by struct gpd_link object containing
pointers to the master and the slave and two struct list_head
members allowing it to hook into two lists (the master's list
of "master" links and the slave's list of "slave" links). This
allows the code to get to the link from each side (either from
the master or from the slave) and follow it in each direction.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The next patch will make it possible for a generic PM domain to have
multiple parents (i.e. multiple PM domains it depends on). To
prepare for that change it is necessary to change pm_genpd_poweron()
so that it doesn't jump to the start label after running itself
recursively for the parent domain. For this purpose, introduce a new
PM domain status value GPD_STATE_WAIT_PARENT that will be set by
pm_genpd_poweron() before calling itself recursively for the parent
domain and modify the code in drivers/base/power/domain.c so that
the GPD_STATE_WAIT_PARENT status is guaranteed to be preserved during
the execution of pm_genpd_poweron() for the parent.
This change also causes pm_genpd_add_subdomain() and
pm_genpd_remove_subdomain() to wait for started pm_genpd_poweron() to
complete and allows pm_genpd_runtime_resume() to avoid dropping the
lock after powering on the PM domain.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
If pm_genpd_remove_subdomain() is called to remove a PM domain's
subdomain and pm_genpd_poweron() is called for that subdomain at
the same time, and the pm_genpd_poweron() called by it recursively
for the parent returns an error, the first pm_genpd_poweron()'s
error code path will attempt to decrement the subdomain counter of
a PM domain that it's not a subdomain of any more.
Rearrange the code in pm_genpd_poweron() to prevent this from
happening.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
After the subdomain counter in struct generic_pm_domain has been
changed into an atomic_t field, it is possible to modify
pm_genpd_poweron() and pm_genpd_poweroff() so that they don't take
the parents locks. This requires pm_genpd_poweron() to increment
the parent's subdomain counter before calling itself recursively
for the parent and to decrement it if an error is to be returned.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Currently, pm_genpd_poweron() and pm_genpd_poweroff() need to take
the parent PM domain's lock in order to modify the parent's counter
of active subdomains in a nonracy way. This causes the locking to be
considerably complex and in fact is not necessary, because the
subdomain counters may be implemented as atomic fields and they
won't have to be modified under a lock.
Replace the unsigned in sd_count field in struct generic_pm_domain
by an atomic_t one and modify the code in drivers/base/power/domain.c
to take this change into account.
This patch doesn't change the locking yet, that is going to be done
in a separate subsequent patch.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The lock member of struct pm_clk_data is of type struct mutex,
which is a problem, because the suspend and resume routines
defined in drivers/base/power/clock_ops.c cannot be executed
with interrupts disabled for this reason. Modify
struct pm_clk_data so that its lock member is a spinlock.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
Some of the entry points to pm runtime are not safe to
call in atomic context unless pm_runtime_irq_safe() has
been called. Inspecting the code, it is not immediately
obvious that the functions sleep at all, as they run
inside a spin_lock_irqsave, but under some conditions
they can drop the lock and turn on irqs.
If a driver incorrectly calls the pm_runtime apis, it can
cause sleeping and irq processing when it expects to stay
in atomic context.
Add might_sleep_if to the majority of the __pm_runtime_* entry points
to enforce correct usage.
Add pm_runtime_put_sync_autosuspend to the list of
functions that can be called in atomic context.
Signed-off-by: Colin Cross <ccross@android.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Function genpd_queue_power_off_work() is not defined for
CONFIG_PM_RUNTIME, so pm_genpd_poweroff_unused() causes a build
error to happen in that case. Fix the problem by making
pm_genpd_poweroff_unused() depend on CONFIG_PM_RUNTIME too.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Currently the use of pm_runtime_put_sync() is not safe from
interrupts-disabled context because rpm_idle() will release the
spinlock and enable interrupts for the idle callbacks. This enables
interrupts during a time where interrupts were expected to be
disabled, and can have strange side effects on drivers that expected
interrupts to be disabled.
This is not a bug since the documentation clearly states that only
_put_sync_suspend() is safe in IRQ-safe mode.
However, pm_runtime_put_sync() could be made safe when in IRQ-safe
mode by releasing the spinlock but not re-enabling interrupts, which
is what this patch aims to do.
Problem was found when using some buggy drivers that set
pm_runtime_irq_safe() and used _put_sync() in interrupts-disabled
context.
Reported-by: Colin Cross <ccross@google.com>
Tested-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The local variable ret is defined twice in pm_genpd_poweron(), which
causes this function to always return 0, even if the PM domain's
.power_on() callback fails, in which case an error code should be
returned.
Remove the wrong second definition of ret and additionally remove an
unnecessary definition of wait from pm_genpd_poweron().
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dev_opp initial value shoule be ERR_PTR(), IS_ERR() is used to check
error.
Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pm-runtime:
OMAP: PM: disable idle on suspend for GPIO and UART
OMAP: PM: omap_device: add API to disable idle on suspend
OMAP: PM: omap_device: add system PM methods for PM domain handling
OMAP: PM: omap_device: conditionally use PM domain runtime helpers
PM / Runtime: Add new helper function: pm_runtime_status_suspended()
PM / Runtime: Consistent utilization of deferred_resume
PM / Runtime: Prevent runtime_resume from racing with probe
PM / Runtime: Replace "run-time" with "runtime" in documentation
PM / Runtime: Improve documentation of enable, disable and barrier
PM: Limit race conditions between runtime PM and system sleep (v2)
PCI / PM: Detect early wakeup in pci_pm_prepare()
PM / Runtime: Return special error code if runtime PM is disabled
PM / Runtime: Update documentation of interactions with system sleep
* pm-domains: (33 commits)
ARM / shmobile: Return -EBUSY from A4LC power off if A3RV is active
PM / Domains: Take .power_off() error code into account
ARM / shmobile: Use genpd_queue_power_off_work()
ARM / shmobile: Use pm_genpd_poweroff_unused()
PM / Domains: Introduce function to power off all unused PM domains
PM / Domains: Queue up power off work only if it is not pending
PM / Domains: Improve handling of wakeup devices during system suspend
PM / Domains: Do not restore all devices on power off error
PM / Domains: Allow callbacks to execute all runtime PM helpers
PM / Domains: Do not execute device callbacks under locks
PM / Domains: Make failing pm_genpd_prepare() clean up properly
PM / Domains: Set device state to "active" during system resume
ARM: mach-shmobile: sh7372 A3RV requires A4LC
PM / Domains: Export pm_genpd_poweron() in header
ARM: mach-shmobile: sh7372 late pm domain off
ARM: mach-shmobile: Runtime PM late init callback
ARM: mach-shmobile: sh7372 D4 support
ARM: mach-shmobile: sh7372 A4MP support
ARM: mach-shmobile: sh7372: make sure that fsi is peripheral of spu2
ARM: mach-shmobile: sh7372 A3SG support
...
Some users are apparently confused by dmesg output from
read_magic_time(), which looks like "real" time and date.
Add the "RTC" string to time stamps printed by read_magic_time() to
avoid that confusion.
Reported-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
cpufreq table allocated by opp_init_cpufreq_table is better
freed by OPP layer itself. This allows future modifications to
the table handling to be transparent to the users.
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Currently pm_genpd_poweroff() discards error codes returned by
the PM domain's .power_off() callback, because it's safer to always
regard the domain as inaccessible to drivers after a failing
.power_off(). Still, there are situations in which the low-level
code may want to indicate that it doesn't want to power off the
domain, so allow it to do that by returning -EBUSY from .power_off().
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
Make pd_power_down_a3rv() use genpd_queue_power_off_work() to queue
up the powering off of the A4LC domain to avoid queuing it up when
it is pending.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
Add a new function pm_genpd_poweroff_unused() queuing up the
execution of pm_genpd_poweroff() for every initialized generic PM
domain. Calling it will cause every generic PM domain without
devices in use to be powered off.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
In theory it is possible that pm_genpd_poweroff() for two different
subdomains of the same parent domain will attempt to queue up the
execution of pm_genpd_poweroff() for the parent twice in a row. This
would lead to unpleasant consequences, so prevent it from happening
by checking if genpd->power_off_work is pending before attempting to
queue it up.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Kevin points out that if there's a device that can wake up the system
from sleep states, but it doesn't generate wakeup signals by itself
(they are generated on its behalf by other parts of the system) and
it currently is not enabled to wake up the system (that is,
device_may_wakeup() returns "false" for it), we may need to change
its wakeup settings during system suspend (for example, the device
might have been configured to signal remote wakeup from the system's
working state, as needed by runtime PM). Therefore the generic PM
domains code should invoke the system suspend callbacks provided by
the device's driver, which it doesn't do if the PM domain is powered
off during the system suspend's "prepare" stage. This is a valid
point. Moreover, this code also should make sure that system wakeup
devices that are enabled to wake up the system from sleep states and
have to remain active for this purpose are not suspended while the
system is in a sleep state.
To avoid the above issues, make the generic PM domains' .prepare()
routine, pm_genpd_prepare(), force runtime resume of devices whose
system wakeup settings may need to be changed during system suspend
or that should remain active while the system is in a sleep state to
be able to wake it up from that state.
Reported-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Since every device in a PM domain has its own need_restore
flag, which is set by __pm_genpd_save_device(), there's no need to
walk the domain's device list and restore all devices on an error
from one of the drivers' .runtime_suspend() callbacks.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
A deadlock may occur if one of the PM domains' .start_device() or
.stop_device() callbacks or a device driver's .runtime_suspend() or
.runtime_resume() callback executed by the core generic PM domain
code uses a "wrong" runtime PM helper function. This happens, for
example, if .runtime_resume() from one device's driver calls
pm_runtime_resume() for another device in the same PM domain.
A similar situation may take place if a device's parent is in the
same PM domain, in which case the runtime PM framework may execute
pm_genpd_runtime_resume() automatically for the parent (if it is
suspended at the moment). This, of course, is undesirable, so
the generic PM domains code should be modified to prevent it from
happening.
The runtime PM framework guarantees that pm_genpd_runtime_suspend()
and pm_genpd_runtime_resume() won't be executed in parallel for
the same device, so the generic PM domains code need not worry
about those cases. Still, it needs to prevent the other possible
race conditions between pm_genpd_runtime_suspend(),
pm_genpd_runtime_resume(), pm_genpd_poweron() and pm_genpd_poweroff()
from happening and it needs to avoid deadlocks at the same time.
To this end, modify the generic PM domains code to relax
synchronization rules so that:
* pm_genpd_poweron() doesn't wait for the PM domain status to
change from GPD_STATE_BUSY. If it finds that the status is
not GPD_STATE_POWER_OFF, it returns without powering the domain on
(it may modify the status depending on the circumstances).
* pm_genpd_poweroff() returns as soon as it finds that the PM
domain's status changed from GPD_STATE_BUSY after it's released
the PM domain's lock.
* pm_genpd_runtime_suspend() doesn't wait for the PM domain status
to change from GPD_STATE_BUSY after executing the domain's
.stop_device() callback and executes pm_genpd_poweroff() only
if pm_genpd_runtime_resume() is not executed in parallel.
* pm_genpd_runtime_resume() doesn't wait for the PM domain status
to change from GPD_STATE_BUSY after executing pm_genpd_poweron()
and sets the domain's status to GPD_STATE_BUSY and increments its
counter of resuming devices (introduced by this change) immediately
after acquiring the lock. The counter of resuming devices is then
decremented after executing __pm_genpd_runtime_resume() for the
device and the domain's status is reset to GPD_STATE_ACTIVE (unless
there are more resuming devices in the domain, in which case the
status remains GPD_STATE_BUSY).
This way, for example, if a device driver's .runtime_resume()
callback executes pm_runtime_resume() for another device in the same
PM domain, pm_genpd_poweron() called by pm_genpd_runtime_resume()
invoked by the runtime PM framework will not block and it will see
that there's nothing to do for it. Next, the PM domain's lock will
be acquired without waiting for its status to change from
GPD_STATE_BUSY and the device driver's .runtime_resume() callback
will be executed. In turn, if pm_runtime_suspend() is executed by
one device driver's .runtime_resume() callback for another device in
the same PM domain, pm_genpd_poweroff() executed by
pm_genpd_runtime_suspend() invoked by the runtime PM framework as a
result will notice that one of the devices in the domain is being
resumed, so it will return immediately.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Currently, the .start_device() and .stop_device() callbacks from
struct generic_pm_domain() as well as the device drivers' runtime PM
callbacks used by the generic PM domains code are executed under
the generic PM domain lock. This, unfortunately, is prone to
deadlocks, for example if a device and its parent are boths members
of the same PM domain. For this reason, it would be better if the
PM domains code didn't execute device callbacks under the lock.
Rework the locking in the generic PM domains code so that the lock
is dropped for the execution of device callbacks. To this end,
introduce PM domains states reflecting the current status of a PM
domain and such that the PM domain lock cannot be acquired if the
status is GPD_STATE_BUSY. Make threads attempting to acquire a PM
domain's lock wait until the status changes to either
GPD_STATE_ACTIVE or GPD_STATE_POWER_OFF.
This change by itself doesn't fix the deadlock problem mentioned
above, but the mechanism introduced by it will be used for for this
purpose by a subsequent patch.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
