Commit Graph

147 Commits

Author SHA1 Message Date
Rafael J. Wysocki d441fe25e7 Merge branches 'pm-domains' and 'pm-cpufreq'
* pm-domains:
  PM / Domains: Fix bad of_node_put() in failure paths of genpd_dev_pm_attach()
  PM / Domains: Validate cases of a non-bound driver in genpd governor

* pm-cpufreq:
  cpufreq: use last policy after online for drivers with ->setpolicy
2015-12-04 14:01:42 +01:00
Eric Anholt 265e2cf672 PM / Domains: Fix bad of_node_put() in failure paths of genpd_dev_pm_attach()
It looks like these meant to be unreffing the
of_parse_phandle_with_args() node, since the error paths above it
don't do of_node_put.  That function returns a new ref in pd_args.np,
though, not a new ref on dev->of_node.  Also, it would have leaked the
ref in the success case.

Fixes "ERROR: Bad of_node_put()" on bcm2835 in the -EPROBE_DEFER case.

Fixes: aa42240ab2 (PM / Domains: Add generic OF-based PM domain look-up)
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Cc: 3.18+ <stable@vger.kernel.org> # 3.18+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-04 01:21:17 +01:00
Linus Torvalds be23c9d20b More power management and ACPI updates for v4.4-rc1
- Support for the ACPI _CCA configuration object intended to tell
    the OS whether or not a bus master device supports hardware
    managed cache coherency and a new set of functions to allow
    drivers to check the cache coherency support for devices in a
    platform firmware interface agnostic way (Suravee Suthikulpanit,
    Jeremy Linton).
 
  - ACPI backlight quirks for ESPRIMO Mobile M9410 and Dell XPS L421X
    (Aaron Lu, Hans de Goede).
 
  - Fixes for the arm_big_little and s5pv210-cpufreq cpufreq drivers
    (Jon Medhurst, Nicolas Pitre).
 
  - kfree()-related fixup for the recently introduced CPPC cpufreq
    frontend (Markus Elfring).
 
  - intel_pstate fix reducing kernel log noise on systems where
    P-states are managed by hardware (Prarit Bhargava).
 
  - intel_pstate maintainers information update (Srinivas Pandruvada).
 
  - cpufreq core optimization related to the handling of delayed work
    items used by governors (Viresh Kumar).
 
  - Locking fixes and cleanups of the Operating Performance Points
    (OPP) framework (Viresh Kumar).
 
  - Generic power domains framework cleanups (Lina Iyer).
 
  - cpupower tool updates (Jacob Tanenbaum, Sriram Raghunathan,
    Thomas Renninger).
 
  - turbostat tool updates (Len Brown).
 
 /
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Merge tag 'pm+acpi-4.4-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management and ACPI updates from Rafael Wysocki:
 "The only new feature in this batch is support for the ACPI _CCA device
  configuration object, which it a pre-requisite for future ACPI PCI
  support on ARM64, but should not affect the other architectures.

  The rest is fixes and cleanups, mostly in cpufreq (including
  intel_pstate), the Operating Performace Points (OPP) framework and
  tools (cpupower and turbostat).

  Specifics:

   - Support for the ACPI _CCA configuration object intended to tell the
     OS whether or not a bus master device supports hardware managed
     cache coherency and a new set of functions to allow drivers to
     check the cache coherency support for devices in a platform
     firmware interface agnostic way (Suravee Suthikulpanit, Jeremy
     Linton).

   - ACPI backlight quirks for ESPRIMO Mobile M9410 and Dell XPS L421X
     (Aaron Lu, Hans de Goede).

   - Fixes for the arm_big_little and s5pv210-cpufreq cpufreq drivers
     (Jon Medhurst, Nicolas Pitre).

   - kfree()-related fixup for the recently introduced CPPC cpufreq
     frontend (Markus Elfring).

   - intel_pstate fix reducing kernel log noise on systems where
     P-states are managed by hardware (Prarit Bhargava).

   - intel_pstate maintainers information update (Srinivas Pandruvada).

   - cpufreq core optimization related to the handling of delayed work
     items used by governors (Viresh Kumar).

   - Locking fixes and cleanups of the Operating Performance Points
     (OPP) framework (Viresh Kumar).

   - Generic power domains framework cleanups (Lina Iyer).

   - cpupower tool updates (Jacob Tanenbaum, Sriram Raghunathan, Thomas
     Renninger).

   - turbostat tool updates (Len Brown)"

* tag 'pm+acpi-4.4-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits)
  PCI: ACPI: Add support for PCI device DMA coherency
  PCI: OF: Move of_pci_dma_configure() to pci_dma_configure()
  of/pci: Fix pci_get_host_bridge_device leak
  device property: ACPI: Remove unused DMA APIs
  device property: ACPI: Make use of the new DMA Attribute APIs
  device property: Adding DMA Attribute APIs for Generic Devices
  ACPI: Adding DMA Attribute APIs for ACPI Device
  device property: Introducing enum dev_dma_attr
  ACPI: Honor ACPI _CCA attribute setting
  cpufreq: CPPC: Delete an unnecessary check before the function call kfree()
  PM / OPP: Add opp_rcu_lockdep_assert() to _find_device_opp()
  PM / OPP: Hold dev_opp_list_lock for writers
  PM / OPP: Protect updates to list_dev with mutex
  PM / OPP: Propagate error properly from dev_pm_opp_set_sharing_cpus()
  cpufreq: s5pv210-cpufreq: fix wrong do_div() usage
  MAINTAINERS: update for intel P-state driver
  Creating a common structure initialization pattern for struct option
  cpupower: Enable disabled Cstates if they are below max latency
  cpupower: Remove debug message when using cpupower idle-set -D switch
  cpupower: cpupower monitor reports uninitialized values for offline cpus
  ...
2015-11-12 11:50:33 -08:00
Linus Torvalds f66477a0ae The majority of the changes are driver updates and new device
support. The core framework is mostly unchanged this time
 around, with only a couple patches to expose a clk provider
 API and make getting clk parent names from DT more robust.
 
 Driver updates:
 
 - Support for clock controllers found on Broadcom Northstar
   SoCs and bcm2835 SoC
 
 - Support for Allwinner audio clocks
 
 - A few cleanup patches for Tegra drivers and support for the
   highest DFLL frequencies on Tegra124
 
 - Samsung exynos7 fixes and improvements
 
 - i.Mx SoC updates to add a few missing clocks and keep debug
   uart clocks on during kernel intialization
 
 - Some mediatek cleanups and support for more subsystem clocks
 
 - Support for msm8916 gpu/audio clocks and qcom's GDSC power domain
   controllers
 
 - A new driver for the Silabs si514 clock chip
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Merge tag 'clk-for-linus-20151104' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux

Pull clk updates from Stephen Boyd:
 "The majority of the changes are driver updates and new device support.
  The core framework is mostly unchanged this time around, with only a
  couple patches to expose a clk provider API and make getting clk
  parent names from DT more robust.

  Driver updates:

   - Support for clock controllers found on Broadcom Northstar SoCs and
     bcm2835 SoC

   - Support for Allwinner audio clocks

   - A few cleanup patches for Tegra drivers and support for the highest
     DFLL frequencies on Tegra124

   - Samsung exynos7 fixes and improvements

   - i.Mx SoC updates to add a few missing clocks and keep debug uart
     clocks on during kernel intialization

   - Some mediatek cleanups and support for more subsystem clocks

   - Support for msm8916 gpu/audio clocks and qcom's GDSC power domain
     controllers

   - A new driver for the Silabs si514 clock chip"

* tag 'clk-for-linus-20151104' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (143 commits)
  clk: qcom: msm8960: Fix dsi1/2 halt bits
  clk: lpc18xx-cgu: fix potential system hang when disabling unused clocks
  clk: lpc18xx-ccu: fix potential system hang when disabling unused clocks
  clk: Add clk_hw_is_enabled() for use by clk providers
  clk: Add stubs for of_clk_*() APIs when CONFIG_OF=n
  clk: versatile-icst: fix memory leak
  clk: Remove clk_{register,unregister}_multiplier()
  clk: iproc: define Broadcom NS2 iProc clock binding
  clk: iproc: define Broadcom NSP iProc clock binding
  clk: ns2: add clock support for Broadcom Northstar 2 SoC
  clk: iproc: Separate status and control variables
  clk: iproc: Split off dig_filter
  clk: iproc: Add PLL base write function
  clk: nsp: add clock support for Broadcom Northstar Plus SoC
  clk: iproc: Add PWRCTRL support
  clk: cygnus: Convert all macros to all caps
  ARM: cygnus: fix link failures when CONFIG_COMMON_CLK_IPROC is disabled
  clk: imx31: add missing of_node_put
  clk: imx27: add missing of_node_put
  clk: si5351: add missing of_node_put
  ...
2015-11-05 12:59:36 -08:00
Lina Iyer 2547923d1c PM / Domains: Allocate memory outside domain locks
In preparation for supporting IRQ-safe domains, allocate domain data
outside the domain locks. These functions are not called in an atomic
context, so we can always allocate memory using GFP_KERNEL. By
allocating memory before the locks, we can safely lock the domain using
spinlocks instead of mutexes.

Reviewed-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-02 02:26:17 +01:00
Lina Iyer 298cd0f088 PM / Domains: Remove dev->driver check for runtime PM
Remove check for driver of a device, for runtime PM. Device may be
suspended without an explicit driver. This check seems to be vestigial
and incorrect in the current context.

Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-02 02:23:11 +01:00
Ulf Hansson 2b1d88cda3 PM / Domains: Merge measurements for PM QoS device latencies
Measure latency does by itself contribute to an increased latency, thus we
should avoid it when it isn't needed.

By merging the latency measurements for the ->save_state() and the
->stop() callbacks, we get one measurement instead of two and we get one
value to store instead of two. Let's also apply the likewise change for
the ->start() and ->restore_state() callbacks.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Lina Iyer <lina.iyer@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-28 04:33:04 +01:00
Ulf Hansson 51cda84489 PM / Domains: Don't measure ->start|stop() latency in system PM callbacks
Measure latency does by itself contribute to an increased latency, thus we
should avoid it when it isn't needed.

Genpd measures latencies in the system PM phase for the ->start|stop()
callbacks and is thus affecting the system PM suspend/resume time.
Moreover these latencies are validated only at runtime PM suspend/resume.

To this reasoning, let's decide to leave these measurements out of the
system PM phase. There should be plenty of occasions during runtime PM to
perform these measurements anyway.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Lina Iyer <lina.iyer@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-28 04:33:04 +01:00
Ulf Hansson 7420aa4fed PM / Domains: Rename *pm_genpd_poweron|poweroff()
This is another step to get consistent names of functions in genpd. Let's
rename the internal *pm_genpd_poweron|poweroff() into
*genpd_poweron|poweroff().

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-14 02:31:54 +02:00
Ulf Hansson ea823c7cbf PM / Domains: Remove pm_genpd_poweron() API
Once genpd could be configured to be built with CONFIG_PM_RUNTIME unset
(nowadays CONFIG_PM), the pm_genpd_poweron() API served a purpose, since
it allowed users to power on a PM domain.

As such configuration no longer is supported, users shall solely rely on
using some of the runtime PM APIs to power on a PM domain.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-12 23:27:02 +02:00
Ulf Hansson bb4b72fc63 PM / Domains: Remove pm_genpd_poweroff_unused() API
As the last user of the pm_genpd_poweroff_unused() API has moved into
relying on genpd to deal with this internally from a late_initcall, let's
remove the API.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-12 23:27:02 +02:00
Ulf Hansson f96b3c4f34 PM / Domains: Remove in_progress counter from struct generic_pm_domain
Commit ba2bbfbf63 ("PM / Domains: Remove intermediate states..") changed
the power off sequence (pm_genpd_poweroff()), which from locking point of
view means the genpd mutex is held throughout the sequence.

The above change means the in_progress counter can't be updated while
pm_genpd_poweroff() is executing, which allows us to remove the counter.

Instead we inform pm_genpd_poweroff() via a bool parameter, to indicate
whether we call it from the scheduled work or from the ->runtime_suspend()
callback, since that all that matters.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-12 23:19:55 +02:00
Stephen Boyd d60ee966b2 PM / Domains: Make pm_genpd_{add,remove}_subdomain() available to modules
Export these symbols so they can be used in loadable kernel
modules.

Cc: Rob Clark <robdclark@gmail.com>
Cc: Rajendra Nayak <rnayak@codeaurora.org>
Cc: Kevin Hilman <khilman@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-08 23:52:55 -07:00
Rafael J. Wysocki 1462206cbc PM / domains: Drop unused label
Drop the "out" label in __pm_genpd_poweron() that's not used any more.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-27 15:20:30 +02:00
Daniel Lezcano cea3ad93d9 PM / Domains: Remove cpuidle attach
The power domains code allows to tie a cpuidle state with a power domain.

Preventing the cpuidle framework to enter a specific idle state by disabling
from the power domain framework is a good idea. Unfortunately, the current
implementation has some gaps with a SMP system and a complex cpuidle
implementation. Enabling a power domain wakes up all the cpus even if a cpu
does not belong to the power domain.

There is some work to do a logical representation with the power domains of
the hardware dependencies (eg. a cpu belongs to a power domains, these power
domains belong to a higher power domain for a cluster, etc ...). A new code
relying on the genpd hierarchy to disable the idle states would make more
sense.

As the unique user of this code has been removed, let's wipe out this code
to prevent new user and to have a clean place to put a new implementation.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-26 02:43:32 +02:00
Ulf Hansson c6f7b48e7e PM / Domains: Remove name based API for genpd
As all users of the named based APIs now have converted to the non-named
based APIs, the time has come to remove them.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-26 02:02:27 +02:00
Jon Hunter 30e7a65b3f PM / Domains: Ensure subdomain is not in use before removing
The function pm_genpd_remove_subdomain() removes a subdomain from a
generic PM domain, however, it does not check if the subdomain has any
slave domains or device attached before doing so. Therefore, add a test
to verify that the subdomain does not have any slave domains associated
or any device attached before removing.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-05 03:33:19 +02:00
Ulf Hansson 29e47e2173 PM / Domains: Try power off masters in error path of __pm_genpd_poweron()
While powering up a genpd, its domain masters are first being powered up.
In the error path of __pm_genpd_poweron(), we didn't care to try power off
these domain masters. Let's deal with that to avoid leaving unused PM
domains powered.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-03 02:53:53 +02:00
Jon Hunter 8bb6944e5a PM / Domains: Fix typo in description of genpd_dev_pm_detach()
The function genpd_dev_pm_detach() detaches a device from a PM domain,
however, in the description, the "dev" argument for the function is
described as the device to "attach" instead of "detach". Correct this.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-08-29 01:55:39 +02:00
Rajendra Nayak be5ed55de0 PM / Domains: Make pm_genpd_init() available to modules
Export symbol pm_genpd_init so it can be used in loadable
kernel modules

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-08-29 01:53:37 +02:00
Geert Uytterhoeven 15dec67ae3 PM / domains: Align column headers and data in pm_genpd_summary output
"domain": header is indented by 4, data by 0 spaces => 0 spaces
"/device": header is indented by 11, data by 4 spaces => 4 spaces
"slaves": header is indented by 47, data by 49 spaces => 48 spaces

Ruler:
    1234567890123456789012345678901234567890123456789012345678901234567890

Before:

	domain                      status         slaves
	       /device                                      runtime status
    ----------------------------------------------------------------------
    a3sp                            on               a2us
	/devices/platform/e60b0000.i2c                      suspended

After:

    domain                          status          slaves
	/device                                             runtime status
    ----------------------------------------------------------------------
    a3sp                            on              a2us
	/devices/platform/e60b0000.i2c                      suspended

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-08-29 01:50:07 +02:00
Jon Hunter 311fa6adf9 PM / Domains: Return -EPROBE_DEFER if we fail to init or turn-on domain
When a device is probed, the function dev_pm_domain_attach() is called
to see if there is a power-domain that is associated with the device and
needs to be turned on. If dev_pm_domain_attach() does not return
-EPROBE_DEFER then the device will be probed.

For devices using genpd, dev_pm_domain_attach() will call
genpd_dev_pm_attach(). If genpd_dev_pm_attach() does not find a power
domain associated with the device then it returns an error code not
equal to -EPROBE_DEFER to allow the device to be probed. However, if
genpd_dev_pm_attach() does find a power-domain that is associated with
the device, then it does not return -EPROBE_DEFER on failure and hence
the device will still be probed. Furthermore, genpd_dev_pm_attach() does
not check the error code returned by pm_genpd_poweron() to see if the
power-domain was turned on successfully.

Fix this by checking the return code from pm_genpd_poweron() and
returning -EPROBE_DEFER from genpd_dev_pm_attach on failure, if there
is a power-domain associated with the device.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-31 23:34:12 +02:00
Ulf Hansson ba2bbfbf63 PM / Domains: Remove intermediate states from the power off sequence
Genpd's ->runtime_suspend() (assigned to pm_genpd_runtime_suspend())
doesn't immediately walk the hierarchy of ->runtime_suspend() callbacks.
Instead, pm_genpd_runtime_suspend() calls pm_genpd_poweroff() which
postpones that until *all* the devices in the genpd are runtime suspended.

When pm_genpd_poweroff() discovers that the last device in the genpd is
about to be runtime suspended, it calls __pm_genpd_save_device() for *all*
the devices in the genpd sequentially. Furthermore,
__pm_genpd_save_device() invokes the ->start() callback, walks the
hierarchy of the ->runtime_suspend() callbacks and invokes the ->stop()
callback. This causes a "thundering herd" problem.

Let's address this issue by having pm_genpd_runtime_suspend() immediately
walk the hierarchy of the ->runtime_suspend() callbacks, instead of
postponing that to the power off sequence via pm_genpd_poweroff(). If the
selected ->runtime_suspend() callback doesn't return an error code, call
pm_genpd_poweroff() to see if it's feasible to also power off the PM
domain.

Adopting this change enables us to simplify parts of the code in genpd,
for example the locking mechanism. Additionally, it gives some positive
side effects, as described below.

i)
One device's ->runtime_resume() latency is no longer affected by other
devices' latencies in a genpd.

The complexity genpd has to support the option to abort the power off
sequence suffers from latency issues. More precisely, a device that is
requested to be runtime resumed, may end up waiting for
__pm_genpd_save_device() to complete its operations for *another* device.
That's because pm_genpd_poweroff() can't confirm an abort request while it
waits for __pm_genpd_save_device() to return.

As this patch removes the intermediate states in pm_genpd_poweroff() while
powering off the PM domain, we no longer need the ability to abort that
sequence.

ii)
Make pm_runtime[_status]_suspended() reliable when used with genpd.

Until the last device in a genpd becomes idle, pm_genpd_runtime_suspend()
will return 0 without actually walking the hierarchy of the
->runtime_suspend() callbacks. However, by returning 0 the runtime PM core
considers the device as runtime_suspended, so
pm_runtime[_status]_suspended() will return true, even though the device
isn't (yet) runtime suspended.

After this patch, since pm_genpd_runtime_suspend() immediately walks the
hierarchy of the ->runtime_suspend() callbacks,
pm_runtime[_status]_suspended() will accurately reflect the status of the
device.

iii)
Enable fine-grained PM through runtime PM callbacks in drivers/subsystems.

There are currently cases were drivers/subsystems implements runtime PM
callbacks to deploy fine-grained PM (e.g. gate clocks, move pinctrl to
power-save state, etc.). While using the genpd, pm_genpd_runtime_suspend()
postpones invoking these callbacks until *all* the devices in the genpd
are runtime suspended. In essence, one runtime resumed device prevents
fine-grained PM for other devices within the same genpd.

After this patch, since pm_genpd_runtime_suspend() immediately walks the
hierarchy of the ->runtime_suspend() callbacks, fine-grained PM is enabled
throughout all the levels of runtime PM callbacks.

iiii)
Enable fine-grained PM for IRQ safe devices

Per the definition for an IRQ safe device, its runtime PM callbacks must
be able to execute in atomic context. In the path while genpd walks the
hierarchy of the ->runtime_suspend() callbacks for the device, it uses a
mutex. Therefore, genpd prevents that path to be executed for IRQ safe
devices.

As this patch changes pm_genpd_runtime_suspend() to immediately walk the
hierarchy of the ->runtime_suspend() callbacks and without needing to use
a mutex, fine-grained PM is enabled throughout all the levels of runtime
PM callbacks for IRQ safe devices.

Unfortunately this patch also comes with a drawback, as described in the
summary below.

Driver's/subsystem's runtime PM callbacks may be invoked even when the
genpd hasn't actually powered off the PM domain, potentially introducing
unnecessary latency.

However, in most cases, saving/restoring register contexts for devices are
typically fast operations or can be optimized in device specific ways
(e.g. shadow copies of register contents in memory, device-specific checks
to see if context has been lost before restoring context, etc.).

Still, in some cases the driver/subsystem may suffer from latency if
runtime PM is used in a very fine-grained manner (e.g. for each IO request
or xfer). To prevent that extra overhead, the driver/subsystem may deploy
the runtime PM autosuspend feature.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-31 23:31:52 +02:00
Geert Uytterhoeven 93af5e9354 PM / Domains: Avoid infinite loops in attach/detach code
If pm_genpd_{add,remove}_device() keeps on failing with -EAGAIN, we end
up with an infinite loop in genpd_dev_pm_{at,de}tach().

This may happen due to a genpd.prepared_count imbalance.  This is a bug
elsewhere, but it will result in a system lock up, possibly during
reboot of an otherwise functioning system.

To avoid this, put a limit on the maximum number of loop iterations,
using an exponential back-off mechanism.  If the limit is reached, the
operation will just fail.  An error message is already printed.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-07 01:13:07 +02:00
Geert Uytterhoeven a4630c6127 PM / Domains: Skip timings during syscore suspend/resume
The PM Domain code uses ktime_get() to perform various latency
measurements.  However, if ktime_get() is called while timekeeping is
suspended, the following warning is printed:

    WARNING: CPU: 0 PID: 1340 at kernel/time/timekeeping.c:576 ktime_get+0x3

This happens when resuming the PM Domain that contains the clock events
source, which calls pm_genpd_syscore_poweron(). Chain of operations is:

    timekeeping_resume()
    {
	clockevents_resume()
	    sh_cmt_clock_event_resume()
		pm_genpd_syscore_poweron()
		    pm_genpd_sync_poweron()
			genpd_syscore_switch()
			    genpd_power_on()
				ktime_get(), but timekeeping_suspended == 1
	...
	timekeeping_suspended = 0;
    }

Fix this by adding a "timed" parameter to genpd_power_{on,off}() and
pm_genpd_sync_power{off,on}(), to indicate whether latency measurements
are allowed.  This parameter is passed as false in
genpd_syscore_switch() (i.e. during syscore suspend/resume), and true in
all other cases.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-15 22:36:02 +02:00
Russell King df6a0d6f63 PM / domains: avoid potential oops in pm_genpd_remove_device()
pm_genpd_remove_device() tries hard to validate the generic PM domain
passed to it, but the validation is not complete.

dev->pm_domain contains a struct dev_pm_domain, which is the "base
class" of generic PM domains.  Other users of dev_pm_domains include
stuff like vga_switheroo.  Hence, a device could have a generic PM
domain or a vga_switcheroo PM domain in dev->pm_domain.

We need ot be certain that the PM domain is actually valid before we
try to remove it.  We can do this easily as we have a way to get the
current validated generic PM domain for a struct device.  This must
match the generic PM domain being requested for removal.

Convert the code to use this alternative validation method instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-23 23:20:28 +01:00
Russell King 446d999c1c PM / domains: factor out code to get the generic PM domain from a struct device
The PM domain code contains two methods to get the generic PM domain
for a struct device.  One is dev_to_genpd() which is only safe when
we know for certain that the device has a generic PM domain attached.
The other is coded into genpd_dev_pm_detach() which ensures that the
PM domain in the struct device is a generic PM domain (and so is safer).

This commit factors out the safer version, documents it, and hides the
unsafe dev_to_genpd().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-22 22:19:12 +01:00
Russell King 6d7d5c3266 PM / domains: quieten down generic pm domains
PM domains are rather noisy; scheduling behaviour can cause callbacks
to take longer, which causes them to spit out a warning-level message
each time a callback takes a little longer than the previous time.
There really isn't a need for this, except when debugging.

Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-22 22:19:12 +01:00
Russell King 632f7ce3f9 PM / Domains: Sync runtime PM status with genpd after probe
Buses which currently supports attaching devices to their PM domains,
will invoke the dev_pm_domain_attach() API from their ->probe()
callbacks. During the attach procedure, genpd power up the PM domain.

In those scenarios where the bus/driver don't need to access its device
during probe, it may leave it in runtime PM suspended state since
that's also the default state. In that way, no notifications through
the runtime PM callbacks will reach the PM domain during probe.

For genpd, the consequence from the above scenario means the PM domain
will remain powered. Therefore, implement the struct dev_pm_domain's
->sync() callback, which is invoked from driver core after the
bus/driver has probed the device. It allows genpd to power off the PM
domain if it's unused.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[ Ulf: Updated patch according to updates in driver core ]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-22 22:15:11 +01:00
Kevin Hilman 66a5ca4b2c PM / Domains: cleanup: rename gpd -> genpd in debugfs interface
To keep consisitency with the rest of the file, use 'genpd' as the
name of the 'struct generic_pm_domain' pointer instead of 'gpd'.

This is just a rename, no functional changes.

Signed-off-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-04 14:18:44 +01:00
Ulf Hansson b472c2faf4 PM / Domains: Handle errors from genpd's ->attach_dev() callback
The optional genpd's ->attach_dev() callback is invoked from
__pm_genpd_add_device(). Let's add error handling from the response
from this callback and propagate the error code.

When __pm_genpd_add_device() is invoked through the generic OF-based PM
domain look-up path, the device is being probed. Returning an error
will mean the device won't be attached to its PM domain. Errors of
-EPROBE_DEFER get special treatment and is propagated to the driver
core.

Therefore this change also enables the ->attach_dev() callback to
be able to request for a deferred probe sequence.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03 22:56:54 +01:00
Ulf Hansson f104e1e5ef PM / Domains: Re-order initialization of generic_pm_domain_data
Move the initialization of the struct generic_pm_domain_data into
genpd_alloc_dev_data(), including the assignment of the device's
->pm_domain() callback. Make corresponding changes to
genpd_free_dev_data().

These changes will make the related code more readable. It will also
decrease the critical regions for where genpd's mutex is being held and
for where the device's power related spinlock is being held.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03 22:56:54 +01:00
Ulf Hansson 3e235685de PM / Domains: Free pm_subsys_data in error path in __pm_genpd_add_device()
The error path in __pm_genpd_add_device() didn't decrease the reference
to the struct pm_subsys_data.

Let's move the calls to dev_pm_get|put_subsys_data() into
genpd_alloc|free_dev_data() to fix this issue and thus prevent a
potential memory leakage.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03 22:56:54 +01:00
Ulf Hansson c0356db7d1 PM / Domains: Eliminate the mutex for the generic_pm_domain_data
While adding devices to their PM domains, dev_pm_qos_add_notifier() was
invoked while allocating the generic_pm_domain_data for the device.

Since the generic_pm_domain_data's device pointer will be assigned
after allocation, the ->genpd_dev_pm_qos_notifier() callback could be
called prior having a valid pointer to the device. Similar scenario
existed while removing a device from a genpd.

To cope with these scenarios a mutex was used to protect the pointer to
the device.

By re-order the sequence for when dev_pm_qos_add|remove_notifier() are
invoked, we make sure the ->genpd_dev_pm_qos_notifier() callback are
always called with a valid device pointer available.

In this way, we eliminate the need for protecting the pointer and thus
we can remove the mutex from the struct generic_pm_domain_data.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03 22:56:53 +01:00
Ulf Hansson e07b45cb98 PM / Domains: Don't check for an existing device when adding a new
When adding a device to a genpd, we no longer need to walk genpd's list
of existing devices to verify it hasn't already been added.

Instead we can now rely on the verification of not allowing existing
generic_pm_domain_data for a device, since that has the same meaning.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03 22:56:53 +01:00
Ulf Hansson 14b5306488 PM / Domains: Don't allow an existing generic_pm_domain_data
When adding a device to a genpd, a struct generic_pm_domain_data is
allocated per device.

Verify that there are no existing generic_pm_domain_data for the device
we are about to add, since that tells us it has already been added to a
genpd.

When genpd supported PM domain device callbacks, this was a valid
scenario. Now it isn't so let's return an error code.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03 22:56:53 +01:00
Ulf Hansson c1dbe2fbb3 PM / Domains: Remove reference counting for the generic_pm_domain_data
The reference counting was needed when genpd supported PM domain device
callbacks. Since this option has been removed, let's also remove the
reference counting of the struct generic_pm_domain_data.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03 22:56:52 +01:00
Ulf Hansson 49d400c74a PM / Domains: Rename __pm_genpd_alloc|free_dev_data()
In a step to get consistent names of functions in genpd, rename
the internal __pm_genpd_alloc|free_dev_data() into
gendp_alloc|free_dev_data().

As discussed on the linux-pm list, let's move towards the following
name rules:

Internal functions:
genpd_*
_genpd_*
__genpd_*

External functions:
pm_genpd_*
_pm_genpd_*
__pm_genpd_*

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03 22:56:52 +01:00
Ulf Hansson 382548a62a PM / Domains: Remove pm_genpd_dev_need_restore() API
There are currently no users of this API, let's remove it.

Additionally, if such feature would be needed future wise, a better
option is likely use pm_runtime_set_active|suspended() in some form.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23 23:13:11 +01:00
Rafael J. Wysocki 4f2f277789 Merge branches 'pm-domains', 'powercap' and 'pm-tools'
* pm-domains:
  PM / Domains: Export of_genpd_get_from_provider function

* powercap:
  powercap / RAPL: add IDs for future Xeon CPUs

* pm-tools:
  tools / cpupower: Fix no idle state information return value
  tools / cpupower: Correctly detect if running as root
2014-12-29 21:24:00 +01:00
Amit Daniel Kachhap 7496fcbe8a PM / Domains: Export of_genpd_get_from_provider function
This function looks up a PM domain form the provider. This will be
useful to add parent/child domain relationship from the SoC specific
code. The caller of the function must make sure that PM domain provider
is already registered.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-12-17 02:33:34 +01:00
Rafael J. Wysocki e3d857e1ae Merge branch 'pm-runtime'
* pm-runtime: (25 commits)
  i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.c
  dmaengine / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  drivers: sh / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  e1000e / igb / PM: Eliminate CONFIG_PM_RUNTIME
  MMC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  MFD / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  misc / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  media / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  input / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  iio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  hsi / OMAP / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  i2c-hid / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  drm / exynos / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  gpio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  hwrandom / exynos / PM: Use CONFIG_PM in #ifdef
  block / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  USB / PM: Drop CONFIG_PM_RUNTIME from the USB core
  PM: Merge the SET*_RUNTIME_PM_OPS() macros
  PM / Kconfig: Do not select PM directly from Kconfig files
  PCI / PM: Drop CONFIG_PM_RUNTIME from the PCI core
  ...
2014-12-08 20:00:44 +01:00
Rafael J. Wysocki d30d819dc8 PM: Drop CONFIG_PM_RUNTIME from the driver core
After commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so quite a few
depend on CONFIG_PM or even may be dropped entirely in some cases.

Replace CONFIG_PM_RUNTIME with CONFIG_PM in the PM core code.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-12-04 00:46:58 +01:00
Ulf Hansson c11f6f5bb1 PM / Domains: Initial PM clock support for genpd
It's quite common for PM domains to use PM clocks. Typically from SOC
specific code, the per device PM clock list is created and
pm_clk_suspend|resume() are invoked to handle clock gating/ungating.

A step towards consolidation is to integrate PM clock support into
genpd, which is what this patch does.

In this initial step, the calls to the pm_clk_suspend|resume() are
handled within genpd, but the per device PM clock list still needs to
be created from SOC specific code. It seems reasonable to have gendp to
handle that as well, but that left to future patches to address.

It's not every users of genpd that are keen on using PM clocks, thus we
need to provide this a configuration option for genpd. Therefore let's
add flag field in the genpd struct to keep this information and define
a new GENDP_FLAG_PM_CLK bit for it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-12-04 00:44:44 +01:00
Ulf Hansson 2ed127697e PM / Domains: Power on the PM domain right after attach completes
Vast amount of platform drivers which enables runtime PM, don't invoke
a pm_runtime_get_sync() while probing their devices.

Instead, once they have turned on their PM resourses during ->probe()
and are ready to handle I/O, these invokes pm_runtime_set_active() to
synchronize its state towards the runtime PM core.

From the runtime PM point of view this behavior is perfectly acceptable,
but we encounter probe failures if their corresponding devices resides
in the generic PM domain. The issues are observed for those devices,
which requires its PM domain to stay powered during ->probe() since
that's not being controlled.

While using the generic OF-based PM domain look-up, a device's PM
domain will be attached during the probe sequence. For this path, let's
fix the probe failures, by simply power on the PM domain right after
when it's been attached to the device.

The generic PM domain stays powered until all of its devices becomes
runtime PM enabled and runtime PM suspended.

The old SOCs which makes use of the generic PM domain but don't use the
generic OF-based PM domain look-up, will not be affected from this
change.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-20 21:38:50 +01:00
Rafael J. Wysocki 2e015da0d5 Merge back 'pm-domains' material for 3.19-rc1. 2014-11-18 01:21:39 +01:00
Geert Uytterhoeven c8f0ea4516 PM / Domains: Extract code to power off/on a PM domain
PM domains are powered on/off from various places. Some callers do
latency measurements, others don't. Consolidate using two helper
functions, which always measure the latencies, and update the stored
latencies when needed.

Other minor changes:
  - Use pr_warn() instead of pr_warning(),
  - There's no need to check genpd->name, %s handles NULL pointers fine,
  - Make the warning format strings identical, to save memory.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-14 00:07:31 +01:00
Geert Uytterhoeven 895b31f3b6 PM / Domains: Make genpd parameter of pm_genpd_present() const
The PM domain pointed to by the genpd parameter is never modified.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-14 00:04:36 +01:00
Ulf Hansson 67732cd343 PM / Domains: Fix initial default state of the need_restore flag
The initial state of the device's need_restore flag should'nt depend on
the current state of the PM domain. For example it should be perfectly
valid to attach an inactive device to a powered PM domain.

The pm_genpd_dev_need_restore() API allow us to update the need_restore
flag to somewhat cope with such scenarios. Typically that should have
been done from drivers/buses ->probe() since it's those that put the
requirements on the value of the need_restore flag.

Until recently, the Exynos SOCs were the only user of the
pm_genpd_dev_need_restore() API, though invoking it from a centralized
location while adding devices to their PM domains.

Due to that Exynos now have swithed to the generic OF-based PM domain
look-up, it's no longer possible to invoke the API from a centralized
location. The reason is because devices are now added to their PM
domains during the probe sequence.

Commit "ARM: exynos: Move to generic PM domain DT bindings"
did the switch for Exynos to the generic OF-based PM domain look-up,
but it also removed the call to pm_genpd_dev_need_restore(). This
caused a regression for some of the Exynos drivers.

To handle things more properly in the generic PM domain, let's change
the default initial value of the need_restore flag to reflect that the
state is unknown. As soon as some of the runtime PM callbacks gets
invoked, update the initial value accordingly.

Moreover, since the generic PM domain is verifying that all devices
are both runtime PM enabled and suspended, using pm_runtime_suspended()
while pm_genpd_poweroff() is invoked from the scheduled work, we can be
sure of that the PM domain won't be powering off while having active
devices.

Do note that, the generic PM domain can still only know about active
devices which has been activated through invoking its runtime PM resume
callback. In other words, buses/drivers using pm_runtime_set_active()
during ->probe() will still suffer from a race condition, potentially
probing a device without having its PM domain being powered. That issue
will have to be solved using a different approach.

This a log from the boot regression for Exynos5, which is being fixed in
this patch.

------------[ cut here ]------------
WARNING: CPU: 0 PID: 308 at ../drivers/clk/clk.c:851 clk_disable+0x24/0x30()
Modules linked in:
CPU: 0 PID: 308 Comm: kworker/0:1 Not tainted 3.18.0-rc3-00569-gbd9449f-dirty #10
Workqueue: pm pm_runtime_work
[<c0013c64>] (unwind_backtrace) from [<c0010dec>] (show_stack+0x10/0x14)
[<c0010dec>] (show_stack) from [<c03ee4cc>] (dump_stack+0x70/0xbc)
[<c03ee4cc>] (dump_stack) from [<c0020d34>] (warn_slowpath_common+0x64/0x88)
[<c0020d34>] (warn_slowpath_common) from [<c0020d74>] (warn_slowpath_null+0x1c/0x24)
[<c0020d74>] (warn_slowpath_null) from [<c03107b0>] (clk_disable+0x24/0x30)
[<c03107b0>] (clk_disable) from [<c02cc834>] (gsc_runtime_suspend+0x128/0x160)
[<c02cc834>] (gsc_runtime_suspend) from [<c0249024>] (pm_generic_runtime_suspend+0x2c/0x38)
[<c0249024>] (pm_generic_runtime_suspend) from [<c024f44c>] (pm_genpd_default_save_state+0x2c/0x8c)
[<c024f44c>] (pm_genpd_default_save_state) from [<c024ff2c>] (pm_genpd_poweroff+0x224/0x3ec)
[<c024ff2c>] (pm_genpd_poweroff) from [<c02501b4>] (pm_genpd_runtime_suspend+0x9c/0xcc)
[<c02501b4>] (pm_genpd_runtime_suspend) from [<c024a4f8>] (__rpm_callback+0x2c/0x60)
[<c024a4f8>] (__rpm_callback) from [<c024a54c>] (rpm_callback+0x20/0x74)
[<c024a54c>] (rpm_callback) from [<c024a930>] (rpm_suspend+0xd4/0x43c)
[<c024a930>] (rpm_suspend) from [<c024bbcc>] (pm_runtime_work+0x80/0x90)
[<c024bbcc>] (pm_runtime_work) from [<c0032a9c>] (process_one_work+0x12c/0x314)
[<c0032a9c>] (process_one_work) from [<c0032cf4>] (worker_thread+0x3c/0x4b0)
[<c0032cf4>] (worker_thread) from [<c003747c>] (kthread+0xcc/0xe8)
[<c003747c>] (kthread) from [<c000e738>] (ret_from_fork+0x14/0x3c)
---[ end trace 40cd58bcd6988f12 ]---

Fixes: a4a8c2c496 (ARM: exynos: Move to generic PM domain DT bindings)
Reported-and-tested0by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-11 22:28:44 +01:00
Ulf Hansson c16561e8df PM / Domains: Change prototype for the attach and detach callbacks
Convert the prototypes to return an int in order to support error
handling in these callbacks.

Also, as suggested by Dmitry Torokhov, pass the domain pointer for use
inside the callbacks, and so that they match the existing
power_on/power_off callbacks which currently take the domain pointer.

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
[ khilman: added domain as parameter to callbacks, as suggested by Dmitry ]
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-08 02:23:21 +01:00