Commit Graph

142 Commits

Author SHA1 Message Date
Randy Dunlap 58c256a3a3 PM / sleep: fix kernel-doc warnings in drivers/base/power/main.c
Fix kernel-doc warnings in drivers/base/power/main.c:

Warning(..//drivers/base/power/main.c:473): No description found for parameter 'async'
Warning(..//drivers/base/power/main.c:601): No description found for parameter 'async'
Warning(..//drivers/base/power/main.c:1012): No description found for parameter 'async'
Warning(..//drivers/base/power/main.c:1151): No description found for parameter 'async'
Warning(..//drivers/base/power/main.c:1305): No description found for parameter 'info'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-29 01:32:50 +02:00
Todd E Brandt e8bca479c3 PM / sleep: trace events for device PM callbacks
Adds two trace events which supply the same info that initcall_debug
provides, but via ftrace instead of dmesg. The existing initcall_debug
calls require the pm_print_times_enabled var to be set (either via
sysfs or via the kernel cmd line). The new trace events provide all the
same info as the initcall_debug prints but with less overhead, and also
with coverage of device prepare and complete device callbacks.

These events replace the device_pm_report_time event (which has been
removed). device_pm_callback_start is called first and provides the device
and callback info. device_pm_callback_end is called after with the
device name and error info. The time and pid are gathered from the trace
data headers.

Signed-off-by: Todd Brandt <todd.e.brandt@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-11 02:16:48 +02:00
Todd E Brandt bb3632c610 PM / sleep: trace events for suspend/resume
Adds trace events that give finer resolution into suspend/resume. These
events are graphed in the timelines generated by the analyze_suspend.py
script. They represent large areas of time consumed that are typical to
suspend and resume.

The event is triggered by calling the function "trace_suspend_resume"
with three arguments: a string (the name of the event to be displayed
in the timeline), an integer (case specific number, such as the power
state or cpu number), and a boolean (where true is used to denote the start
of the timeline event, and false to denote the end).

The suspend_resume trace event reproduces the data that the machine_suspend
trace event did, so the latter has been removed.

Signed-off-by: Todd Brandt <todd.e.brandt@intel.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-07 00:18:07 +02:00
Rafael J. Wysocki aae4518b31 PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily
Currently, some subsystems (e.g. PCI and the ACPI PM domain) have to
resume all runtime-suspended devices during system suspend, mostly
because those devices may need to be reprogrammed due to different
wakeup settings for system sleep and for runtime PM.

For some devices, though, it's OK to remain in runtime suspend
throughout a complete system suspend/resume cycle (if the device was in
runtime suspend at the start of the cycle).  We would like to do this
whenever possible, to avoid the overhead of extra power-up and power-down
events.

However, problems may arise because the device's descendants may require
it to be at full power at various points during the cycle.  Therefore the
most straightforward way to do this safely is if the device and all its
descendants can remain runtime suspended until the complete stage of
system resume.

To this end, introduce a new device PM flag, power.direct_complete
and modify the PM core to use that flag as follows.

If the ->prepare() callback of a device returns a positive number,
the PM core will regard that as an indication that it may leave the
device runtime-suspended.  It will then check if the system power
transition in progress is a suspend (and not hibernation in particular)
and if the device is, indeed, runtime-suspended.  In that case, the PM
core will set the device's power.direct_complete flag.  Otherwise it
will clear power.direct_complete for the device and it also will later
clear it for the device's parent (if there's one).

Next, the PM core will not invoke the ->suspend() ->suspend_late(),
->suspend_irq(), ->resume_irq(), ->resume_early(), or ->resume()
callbacks for all devices having power.direct_complete set.  It
will invoke their ->complete() callbacks, however, and those
callbacks are then responsible for resuming the devices as
appropriate, if necessary.  For example, in some cases they may
need to queue up runtime resume requests for the devices using
pm_request_resume().

Changelog partly based on an Alan Stern's description of the idea
(http://marc.info/?l=linux-pm&m=139940466625569&w=2).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
2014-05-16 23:15:44 +02:00
Rafael J. Wysocki 5a2d853ffc Merge branch 'pm-cpufreq'
* pm-cpufreq: (30 commits)
  intel_pstate: Set core to min P state during core offline
  cpufreq: Add stop CPU callback to cpufreq_driver interface
  cpufreq: Remove unnecessary braces
  cpufreq: Fix checkpatch errors and warnings
  cpufreq: powerpc: add cpufreq transition latency for FSL e500mc SoCs
  cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE}
  cpufreq: Do not allow ->setpolicy drivers to provide ->target
  cpufreq: arm_big_little: set 'physical_cluster' for each CPU
  cpufreq: arm_big_little: make vexpress driver depend on bL core driver
  cpufreq: SPEAr: Instantiate as platform_driver
  cpufreq: Remove unnecessary variable/parameter 'frozen'
  cpufreq: Remove cpufreq_generic_exit()
  cpufreq: add 'freq_table' in struct cpufreq_policy
  cpufreq: Reformat printk() statements
  cpufreq: Tegra: Use cpufreq_generic_suspend()
  cpufreq: s5pv210: Use cpufreq_generic_suspend()
  cpufreq: exynos: Use cpufreq_generic_suspend()
  cpufreq: Implement cpufreq_generic_suspend()
  cpufreq: suspend governors on system suspend/hibernate
  cpufreq: move call to __find_governor() to cpufreq_init_policy()
  ...
2014-03-20 13:26:12 +01:00
Viresh Kumar 2f0aea9363 cpufreq: suspend governors on system suspend/hibernate
This patch adds cpufreq suspend/resume calls to dpm_{suspend|resume}()
for handling suspend/resume of cpufreq governors.

Lan Tianyu (Intel) & Jinhyuk Choi (Broadcom) found an issue where the
tunables configuration for clusters/sockets with non-boot CPUs was
lost after system suspend/resume, as we were notifying governors with
CPUFREQ_GOV_POLICY_EXIT on removal of the last CPU for that policy
which caused the tunables memory to be freed.

This is fixed by preventing any governor operations from being
carried out between the device suspend and device resume stages of
system suspend and resume, respectively.

We could have added these callbacks at dpm_{suspend|resume}_noirq()
level, but there is an additional problem that the majority of I/O
devices is already suspended at that point and if cpufreq drivers
want to change the frequency before suspending, then that not be
possible on some platforms (which depend on peripherals like i2c,
regulators, etc).

Reported-and-tested-by: Lan Tianyu <tianyu.lan@intel.com>
Reported-by: Jinhyuk Choi <jinchoi@broadcom.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-06 15:04:12 +01:00
Liu, Chuansheng de377b3972 PM / sleep: Asynchronous threads for suspend_late
In analogy with commits 5af84b8270 and 97df8c1299, using
asynchronous threads can improve the overall suspend_late
time significantly.

This patch is for suspend_late phase.

Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-20 01:30:09 +01:00
Liu, Chuansheng 28b6fd6e37 PM / sleep: Asynchronous threads for suspend_noirq
In analogy with commits 5af84b8270 and 97df8c1299, using
asynchronous threads can improve the overall suspend_noirq
time significantly.

This patch is for suspend_noirq phase.

Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-20 01:30:09 +01:00
Liu, Chuansheng 9e5e7910df PM / sleep: Asynchronous threads for resume_early
In analogy with commits 5af84b8270 and 97df8c1299, using
asynchronous threads can improve the overall resume_early
time significantly.

This patch is for resume_early phase.

Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-20 01:30:09 +01:00
Liu, Chuansheng 76569faa62 PM / sleep: Asynchronous threads for resume_noirq
In analogy with commits 5af84b8270 and 97df8c1299, using
asynchronous threads can improve the overall resume_noirq time
significantly.

One typical case is:
In resume_noirq phase and for the PCI devices, the function
pci_pm_resume_noirq() will be called, and there is one d3_delay
(10ms) at least.

With the way of asynchronous threads, we just need wait d3_delay
time once in parallel for each calling, which saves much time to
resume quickly.

Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-20 01:30:09 +01:00
Liu, Chuansheng 3d2699bc17 PM / sleep: Two flags for async suspend_noirq and suspend_late
The patch is a helper adding two new flags for implementing
async threads for suspend_noirq and suspend_late.

Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-20 01:30:08 +01:00
Rafael J. Wysocki 12205a4b79 Revert "cpufreq: suspend governors on system suspend/hibernate"
Commit 5a87182aa2 (cpufreq: suspend governors on system
suspend/hibernate) causes hibernation problems to happen on
Bjørn Mork's and Paul Bolle's systems, so revert it.

Fixes: 5a87182aa2 (cpufreq: suspend governors on system suspend/hibernate)
Reported-by: Bjørn Mork <bjorn@mork.no>
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-08 01:04:17 +01:00
Rafael J. Wysocki 7cdcec991c Merge branches 'pm-cpuidle' and 'pm-cpufreq'
* pm-cpuidle:
  cpuidle: Check for dev before deregistering it.
  intel_idle: Fixed C6 state on Avoton/Rangeley processors

* pm-cpufreq:
  cpufreq: fix garbage kobjects on errors during suspend/resume
  cpufreq: suspend governors on system suspend/hibernate
2013-12-06 02:17:59 +01:00
Viresh Kumar 5a87182aa2 cpufreq: suspend governors on system suspend/hibernate
This patch adds cpufreq suspend/resume calls to dpm_{suspend|resume}_noirq()
for handling suspend/resume of cpufreq governors.

Lan Tianyu (Intel) & Jinhyuk Choi (Broadcom) found anr issue where
tunables configuration for clusters/sockets with non-boot CPUs was
getting lost after suspend/resume, as we were notifying governors
with CPUFREQ_GOV_POLICY_EXIT on removal of the last cpu for that
policy and so deallocating memory for tunables. This is fixed by
this patch as we don't allow any operation on governors after
device suspend and before device resume now.

Reported-and-tested-by: Lan Tianyu <tianyu.lan@intel.com>
Reported-by: Jinhyuk Choi <jinchoi@broadcom.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog, minor cleanups]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-28 14:47:31 +01:00
Linus Torvalds 82023bb7f7 More ACPI and power management updates for 3.13-rc1
- ACPI-based device hotplug fixes for issues introduced recently and
   a fix for an older error code path bug in the ACPI PCI host bridge
   driver.
 
 - Fix for recently broken OMAP cpufreq build from Viresh Kumar.
 
 - Fix for a recent hibernation regression related to s2disk.
 
 - Fix for a locking-related regression in the ACPI EC driver from
   Puneet Kumar.
 
 - System suspend error code path fix related to runtime PM and
   runtime PM documentation update from Ulf Hansson.
 
 - cpufreq's conservative governor fix from Xiaoguang Chen.
 
 - New processor IDs for intel_idle and turbostat and removal of
   an obsolete Kconfig option from Len Brown.
 
 - New device IDs for the ACPI LPSS (Low-Power Subsystem) driver and
   ACPI-based PCI hotplug (ACPIPHP) cleanup from Mika Westerberg.
 
 - Removal of several ACPI video DMI blacklist entries that are not
   necessary any more from Aaron Lu.
 
 - Rework of the ACPI companion representation in struct device and
   code cleanup related to that change from Rafael J Wysocki,
   Lan Tianyu and Jarkko Nikula.
 
 - Fixes for assigning names to ACPI-enumerated I2C and SPI devices
   from Jarkko Nikula.
 
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Merge tag 'pm+acpi-2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more ACPI and power management updates from Rafael Wysocki:

 - ACPI-based device hotplug fixes for issues introduced recently and a
   fix for an older error code path bug in the ACPI PCI host bridge
   driver

 - Fix for recently broken OMAP cpufreq build from Viresh Kumar

 - Fix for a recent hibernation regression related to s2disk

 - Fix for a locking-related regression in the ACPI EC driver from
   Puneet Kumar

 - System suspend error code path fix related to runtime PM and runtime
   PM documentation update from Ulf Hansson

 - cpufreq's conservative governor fix from Xiaoguang Chen

 - New processor IDs for intel_idle and turbostat and removal of an
   obsolete Kconfig option from Len Brown

 - New device IDs for the ACPI LPSS (Low-Power Subsystem) driver and
   ACPI-based PCI hotplug (ACPIPHP) cleanup from Mika Westerberg

 - Removal of several ACPI video DMI blacklist entries that are not
   necessary any more from Aaron Lu

 - Rework of the ACPI companion representation in struct device and code
   cleanup related to that change from Rafael J Wysocki, Lan Tianyu and
   Jarkko Nikula

 - Fixes for assigning names to ACPI-enumerated I2C and SPI devices from
   Jarkko Nikula

* tag 'pm+acpi-2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (24 commits)
  PCI / hotplug / ACPI: Drop unused acpiphp_debug declaration
  ACPI / scan: Set flags.match_driver in acpi_bus_scan_fixed()
  ACPI / PCI root: Clear driver_data before failing enumeration
  ACPI / hotplug: Fix PCI host bridge hot removal
  ACPI / hotplug: Fix acpi_bus_get_device() return value check
  cpufreq: governor: Remove fossil comment in the cpufreq_governor_dbs()
  ACPI / video: clean up DMI table for initial black screen problem
  ACPI / EC: Ensure lock is acquired before accessing ec struct members
  PM / Hibernate: Do not crash kernel in free_basic_memory_bitmaps()
  ACPI / AC: Remove struct acpi_device pointer from struct acpi_ac
  spi: Use stable dev_name for ACPI enumerated SPI slaves
  i2c: Use stable dev_name for ACPI enumerated I2C slaves
  ACPI: Provide acpi_dev_name accessor for struct acpi_device device name
  ACPI / bind: Use (put|get)_device() on ACPI device objects too
  ACPI: Eliminate the DEVICE_ACPI_HANDLE() macro
  ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node
  cpufreq: OMAP: Fix compilation error 'r & ret undeclared'
  PM / Runtime: Fix error path for prepare
  PM / Runtime: Update documentation around probe|remove|suspend
  cpufreq: conservative: set requested_freq to policy max when it is over policy max
  ...
2013-11-20 13:25:04 -08:00
Rafael J. Wysocki 77aa26514a Merge branch 'pm-runtime'
* pm-runtime:
  PM / Runtime: Fix error path for prepare
  PM / Runtime: Update documentation around probe|remove|suspend
2013-11-19 01:06:49 +01:00
Wolfram Sang 16735d022f tree-wide: use reinit_completion instead of INIT_COMPLETION
Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.

[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 09:32:21 +09:00
Ulf Hansson aa1b9f13b3 PM / Runtime: Fix error path for prepare
If a device prepare callback for some reason would fail, the PM core
prevented the device from going inactive forever.

In this case, to reverse the pm_runtime_get_noresume() we invokes the
asyncronous pm_runtime_put(), thus restoring the usage count.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-14 00:48:19 +01:00
Benoit Goby 70fea60d88 PM / Sleep: Detect device suspend/resume lockup and log event
Rather than hard-lock the kernel, dump the suspend/resume thread stack
and panic() to capture a message in pstore when a driver takes too long
to suspend/resume. Default suspend/resume watchdog timeout is set to 12
seconds to be longer than the usbhid 10 second timeout, but could be
changed at compile time.

Exclude from the watchdog the time spent waiting for children that
are resumed asynchronously and time every device, whether or not they
resumed synchronously.

This patch is targeted for mobile devices where a suspend/resume lockup
could cause a system reboot. Information about failing device can be
retrieved in subsequent boot session by mounting pstore and inspecting
the log. Laptops with EFI-enabled pstore could also benefit from
this feature.

The hardware watchdog timer is likely suspended during this time and
couldn't be relied upon. The soft-lockup detector would eventually tell
that tasks are not scheduled, but would provide little context as to why.
The patch hence uses system timer and assumes it is still active while the
devices are suspended/resumed.

This feature can be enabled/disabled during kernel configuration.

This change is based on earlier work by San Mehat.

Signed-off-by: Benoit Goby <benoit@android.com>
Signed-off-by: Zoran Markovic <zoran.markovic@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-18 13:33:08 +02:00
Shuah Khan 536446772f PM / Sleep: new trace event to print device suspend and resume times
A new trace event is added to PM events to print the time it takes to
suspend and resume a device.  It generates trace messages that
include device, driver, parent information in addition to the type of
PM ops invoked as well as the PM event and error status from the PM
ops. Example trace below:

bash-2239  [000] ....   290.883035: device_pm_report_time: backlight
 acpi_video0 parent=0000:00:02.0 state=freeze ops=class nsecs=332 err=0
bash-2239  [000] ....   290.883041: device_pm_report_time: rfkill rf
kill3 parent=phy0 state=freeze ops=legacy class nsecs=216 err=0
bash-2239  [001] ....   290.973892: device_pm_report_time: ieee80211
 phy0 parent=0000:01:00.0 state=freeze ops=legacy class nsecs=90846477 err=0

bash-2239  [001] ....   293.660129: device_pm_report_time: ieee80211 phy0 parent=0000:01:00.0 state=restore ops=legacy class nsecs=101295162 err=0
bash-2239  [001] ....   293.660147: device_pm_report_time: rfkill rfkill3 parent=phy0 state=restore ops=legacy class nsecs=1804 err=0
bash-2239  [001] ....   293.660157: device_pm_report_time: backlight acpi_video0 parent=0000:00:02.0 state=restore ops=class nsecs=757 err=0

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-27 03:18:35 +02:00
Ulf Hansson af93933974 PM / Runtime: Asyncronous idle|suspend devices at system resume
Use the asyncronous runtime PM API when returning the runtime
reference for the device after the system resume is completed.

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

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-12 13:34:57 +02:00
Rafael J. Wysocki 37530f2bda PM / QoS: Remove device PM QoS sysfs attributes at the right place
Device PM QoS sysfs attributes, if present during device removal,
are removed from within device_pm_remove(), which is too late,
since dpm_sysfs_remove() has already removed the whole attribute
group they belonged to.  However, moving the removal of those
attributes to dpm_sysfs_remove() alone is not sufficient, because
in theory they still can be re-added right after being removed by it
(the device's driver is still bound to it at that point).

For this reason, move the entire desctruction of device PM QoS
constraints to dpm_sysfs_remove() and make it prevent any new
constraints from being added after it has run.  Also, move the
initialization of the power.qos field in struct device to
device_pm_init_common() and drop the no longer needed
dev_pm_qos_constraints_init().

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-04 14:23:12 +01:00
Rafael J. Wysocki 9f6d8f6ab2 PM: Move disabling/enabling runtime PM to late suspend/early resume
Currently, the PM core disables runtime PM for all devices right
after executing subsystem/driver .suspend() callbacks for them
and re-enables it right before executing subsystem/driver .resume()
callbacks for them.  This may lead to problems when there are
two devices such that the .suspend() callback executed for one of
them depends on runtime PM working for the other.  In that case,
if runtime PM has already been disabled for the second device,
the first one's .suspend() won't work correctly (and analogously
for resume).

To make those issues go away, make the PM core disable runtime PM
for devices right before executing subsystem/driver .suspend_late()
callbacks for them and enable runtime PM for them right after
executing subsystem/driver .resume_early() callbacks for them.  This
way the potential conflitcs between .suspend_late()/.resume_early()
and their runtime PM counterparts are still prevented from happening,
but the subtle ordering issues related to disabling/enabling runtime
PM for devices during system suspend/resume are much easier to avoid.

Reported-and-tested-by: Jan-Matthias Braun <jan_braun@gmx.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@deeprootsystems.com>
Cc: 3.4+ <stable@vger.kernel.org>
2013-01-06 00:35:55 +01:00
Linus Torvalds 16642a2e7b Power management updates for 3.7-rc1
* 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
  ...
2012-10-02 18:32:35 -07:00
Rafael J. Wysocki 057d51a126 Merge branch 'pm-sleep'
* pm-sleep:
  PM: Prevent runtime suspend during system resume
  PM / Sleep: use resume event when call dpm_resume_early

Conflicts:
	drivers/base/power/main.c (trivial)
2012-09-24 13:31:38 +02:00
Alan Stern 88d26136a2 PM: Prevent runtime suspend during system resume
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>
2012-09-19 21:59:02 +02:00
Feng Hong 997a031107 PM / Sleep: use resume event when call dpm_resume_early
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>
2012-09-19 14:16:00 +02:00
Rafael J. Wysocki dbf374142d PM / Domains: Move syscore flag from subsys data to struct device
The syscore device PM flag is used to mark the devices (belonging to
a PM domain) that should never be turned off, except for the system
core (syscore) suspend/hibernation and resume stages.  That flag is
stored in the device's struct pm_subsys_data object whose address is
available from struct device.  However, in some situations it may be
convenient to set that flag before the device is added to a PM
domain, so it is better to move it directly to the "power" member of
struct device.  Then, it can be checked by the routines in
drivers/base/power/runtime.c and drivers/base/power/main.c, which is
more straightforward.

This also reduces the number of dev_gpd_data() invocations in the
generic PM domains framework, so the overhead related to the syscore
flag is slightly smaller.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
2012-09-04 01:36:04 +02:00
Rafael J. Wysocki e91c11b1a7 PM: Reorganize device PM initialization
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>
2012-09-04 01:36:03 +02:00
Ming Lei dfe3212e01 PM / Sleep: introduce dpm_for_each_dev
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>
2012-08-17 07:37:35 -07:00
Rafael J. Wysocki 382e159619 Merge branch 'pm-sleep'
* pm-sleep:
  PM / Sleep: call early resume handlers when suspend_noirq fails
2012-07-19 10:39:21 +02:00
Colin Cross 064b021fbe PM / Sleep: call early resume handlers when suspend_noirq fails
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>
2012-07-19 10:38:06 +02:00
Rafael J. Wysocki d52fdf1337 Merge branch 'pm-sleep'
* 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.
2012-07-19 00:03:29 +02:00
Sachin Kamat 7664e96935 PM / Sleep: Add missing static storage class specifiers in main.c
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>
2012-07-18 23:57:47 +02:00
Preeti U Murthy 8651f97bd9 PM / cpuidle: System resume hang fix with cpuidle
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>
2012-07-10 21:34:49 +02:00
Rafael J. Wysocki b2df1d4f8b PM / Sleep: Separate printing suspend times from initcall_debug
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>
2012-07-01 13:31:23 +02:00
Sameer Nanda 4b7760ba0d PM / Sleep: add knob for printing device resume times
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>
2012-07-01 13:31:22 +02:00
Mandeep Singh Baines 1f758b2317 PM / Sleep: Prevent waiting forever on asynchronous suspend after abort
__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>
2012-06-24 23:31:09 +02:00
Rafael J. Wysocki 52d136cc2c PM / Sleep: Look for wakeup events in later stages of device suspend
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>
2012-05-01 21:24:50 +02:00
Rafael J. Wysocki cf579dfb82 PM / Sleep: Introduce "late suspend" and "early resume" of devices
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>
2012-01-29 20:38:29 +01:00
Rafael J. Wysocki 35cd133c61 PM: Run the driver callback directly if the subsystem one is not there
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>
2011-12-21 22:01:05 +01:00
Rafael J. Wysocki 9cf519d1c1 PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers
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>
2011-12-21 22:00:56 +01:00
Rafael J. Wysocki 0c6aebe318 PM / Sleep: Unify diagnostic messages from device suspend/resume
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>
2011-12-06 22:09:45 +01:00
Rafael J. Wysocki 64e94aafb6 PM / Sleep: Simplify device_suspend_noirq()
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>
2011-11-23 21:13:34 +01:00
Rafael J. Wysocki d74e278aaf PM / Sleep: Remove unnecessary label and jumps to it form PM core code
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>
2011-11-23 21:13:24 +01:00
Rafael J. Wysocki 8b258cc8ac PM Sleep: Do not extend wakeup paths to devices with ignore_children set
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>
2011-11-17 21:39:33 +01:00
Paul Gortmaker 1b6bc32f0a drivers/base: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required.
Most of these files were implicitly getting EXPORT_SYMBOL via
device.h which was including module.h, but that path will be broken
soon.

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

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:38 -04:00
Rafael J. Wysocki d033e07856 Merge branch 'pm-domains' into pm-for-linus
* 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
2011-10-22 00:21:52 +02:00
Rafael J. Wysocki 4ca46ff3e0 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>
2011-10-22 00:19:29 +02:00
ShuoX Liu 2a77c46de1 PM / Suspend: Add statistics debugfs file for suspend to RAM
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>
2011-10-16 23:27:45 +02:00