Commit Graph

1044 Commits

Author SHA1 Message Date
Ulf Hansson 4f688748c9 PM / Domains: Check for existing PM domain in dev_pm_domain_attach()
Instead of checking if an existing PM domain pointer has been assigned in
genpd_dev_pm_attach() and acpi_dev_pm_attach(), move the check to the
common path in dev_pm_domain_attach(), thus potentially avoid one
unnecessary check.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-14 22:58:44 +02:00
Ulf Hansson b56d9c9135 PM / Domains: Drop redundant code in genpd while attaching devices
The driver core together with the PM core, nowadays deals with deferring
all probes during the device system sleep phases. Therefore genpd no longer
need to care about this situation, so let's drop the corresponding code.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-14 22:58:44 +02:00
Ulf Hansson ed37884584 PM / Domains: Drop comment in genpd about legacy Samsung DT binding
The parsing of the Samsung specific DT binding is gone, but the comment in
the function header remained. Let's drop the comment to avoid confusions.

Fixes: 001d50c9a1 (PM / Domains: Remove obsolete "samsung,power-domain" check)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-14 22:58:43 +02:00
Ulf Hansson 72038df3c5 PM / Domains: Fix error path during attach in genpd
In case the PM domain fails to be powered on in genpd_dev_pm_attach(), it
returns -EPROBE_DEFER, but keeping the device attached to its PM domain.
This leads to problems when the next attempt to attach is re-tried. More
precisely, in that situation an -EEXIST error code is returned, because the
device already has its PM domain pointer assigned, from the first attempt.

Now, because of the sloppy error handling by the existing callers of
dev_pm_domain_attach(), probing is allowed to continue when -EEXIST is
returned. However, in such case there are no guarantees that the PM domain
is powered on by genpd, which may lead to hangs when buses/drivers tried to
access their devices.

Let's fix this behaviour, simply by detaching the device when powering on
fails in genpd_dev_pm_attach().

Cc: v4.11+ <stable@vger.kernel.org> # v4.11+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-14 22:58:43 +02:00
Tony Lindgren da997b22c4 PM / wakeirq: Add wakeup name to dedicated wake irqs
This makes it easy to grep :wakeup /proc/interrupts.

Suggested-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-02-26 23:23:37 +01:00
Tony Lindgren 69728051f5 PM / wakeirq: Fix unbalanced IRQ enable for wakeirq
If a device is runtime PM suspended when we enter suspend and has
a dedicated wake IRQ, we can get the following warning:

WARNING: CPU: 0 PID: 108 at kernel/irq/manage.c:526 enable_irq+0x40/0x94
[  102.087860] Unbalanced enable for IRQ 147
...
(enable_irq) from [<c06117a8>] (dev_pm_arm_wake_irq+0x4c/0x60)
(dev_pm_arm_wake_irq) from [<c0618360>]
 (device_wakeup_arm_wake_irqs+0x58/0x9c)
(device_wakeup_arm_wake_irqs) from [<c0615948>]
(dpm_suspend_noirq+0x10/0x48)
(dpm_suspend_noirq) from [<c01ac7ac>]
(suspend_devices_and_enter+0x30c/0xf14)
(suspend_devices_and_enter) from [<c01adf20>]
(enter_state+0xad4/0xbd8)
(enter_state) from [<c01ad3ec>] (pm_suspend+0x38/0x98)
(pm_suspend) from [<c01ab3e8>] (state_store+0x68/0xc8)

This is because the dedicated wake IRQ for the device may have been
already enabled earlier by dev_pm_enable_wake_irq_check().  Fix the
issue by checking for runtime PM suspended status.

This issue can be easily reproduced by setting serial console log level
to zero, letting the serial console idle, and suspend the system from
an ssh terminal.  On resume, dmesg will have the warning above.

The reason why I have not run into this issue earlier has been that I
typically run my PM test cases from on a serial console instead over ssh.

Fixes: c843455975 (PM / wakeirq: Enable dedicated wakeirq for suspend)
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-02-12 11:10:09 +01:00
Ulf Hansson a3381e3a65 PM / domains: Fix up domain-idle-states OF parsing
Commit b539cc82d4 (PM / Domains: Ignore domain-idle-states that are
not compatible), made it possible to ignore non-compatible
domain-idle-states OF nodes. However, in case that happens while doing
the OF parsing, the number of elements in the allocated array would
exceed the numbers actually needed, thus wasting memory.

Fix this by pre-iterating the genpd OF node and counting the number of
compatible domain-idle-states nodes, before doing the allocation. While
doing this, it makes sense to rework the code a bit to avoid open coding,
of parts responsible for the OF node iteration.

Let's also take the opportunity to clarify the function header for
of_genpd_parse_idle_states(), about what is being returned in case of
errors.

Fixes: b539cc82d4 (PM / Domains: Ignore domain-idle-states that are not compatible)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Lina Iyer <ilina@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-02-07 12:02:01 +01:00
Ulf Hansson 617fcb6730 PM / runtime: Allow no callbacks in pm_runtime_force_suspend|resume()
The pm_runtime_force_suspend|resume() helpers currently requires the device
to at some level (PM domain, bus, etc), have the ->runtime_suspend|resume()
callbacks assigned for it, else -ENOSYS is returned as an error.

However, there are no reason for this requirement, so let's simply remove
it by allowing these callbacks to be NULL.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-17 12:42:49 +01:00
Rafael J. Wysocki 1f5c685526 PM / runtime: Check ignore_children in pm_runtime_need_not_resume()
Modify pm_runtime_need_not_resume() to make it avoid taking
power.child_count for devices with power.ignore_children which
is consistent with the runtime PM usage of these fields.

Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2018-01-15 17:21:19 +01:00
Rafael J. Wysocki 4918e1f87c PM / runtime: Rework pm_runtime_force_suspend/resume()
One of the limitations of pm_runtime_force_suspend/resume() is that
if a parent driver wants to use these functions, all of its child
drivers generally have to do that too because of the parent usage
counter manipulations necessary to get the correct state of the parent
during system-wide transitions to the working state (system resume).
However, that limitation turns out to be artificial, so remove it.

Namely, pm_runtime_force_suspend() only needs to update the children
counter of its parent (if there's is a parent) when the device can
stay in suspend after the subsequent system resume transition, as
that counter is correct already otherwise.  Now, if the parent's
children counter is not updated, it is not necessary to increment
the parent's usage counter in that case any more, as long as the
children counters of devices are checked along with their usage
counters in order to decide whether or not the devices may be left
in suspend after the subsequent system resume transition.

Accordingly, modify pm_runtime_force_suspend() to only call
pm_runtime_set_suspended() for devices whose usage and children
counters are at the "no references" level (the runtime PM status
of the device needs to be updated to "suspended" anyway in case
this function is called once again for the same device during the
transition under way), drop the parent usage counter incrementation
from it and update pm_runtime_force_resume() to compensate for these
changes.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2018-01-15 01:36:33 +01:00
Rafael J. Wysocki 46fa233acf Merge generic power domains (genpd) material for v4.16 into pm-core 2018-01-15 01:34:17 +01:00
Rafael J. Wysocki 17218e0092 PM / genpd: Stop/start devices without pm_runtime_force_suspend/resume()
There are problems with calling pm_runtime_force_suspend/resume()
to "stop" and "start" devices in genpd_finish_suspend() and
genpd_resume_noirq() (and in analogous hibernation-specific genpd
callbacks) after commit 122a22377a (PM / Domains: Stop/start
devices during system PM suspend/resume in genpd) as those routines
do much more than just "stopping" and "starting" devices (which was
the stated purpose of that commit) unnecessarily and may not play
well with system-wide PM driver callbacks.

First, consider the pm_runtime_force_suspend() in
genpd_finish_suspend().  If the current runtime PM status of the
device is "suspended", that function most likely does the right thing
by ignoring the device, because it should have been "stopped" already
and whatever needed to be done to deactivate it shoud have been done.
In turn, if the runtime PM status of the device is "active",
genpd_runtime_suspend() is called for it (indirectly) and (1) runs
the ->runtime_suspend callback provided by the device's driver
(assuming no bus type with ->runtime_suspend of its own), (2) "stops"
the device and (3) checks if the domain can be powered down, and then
(4) the device's runtime PM status is changed to "suspended".  Out of
the four actions above (1) is not necessary and it may be outright
harmful, (3) is pointless and (4) is questionable.  The only
operation that needs to be carried out here is (2).

The reason why (1) is not necessary is because the system-wide
PM callbacks provided by the device driver for the transition in
question have been run and they should have taken care of the
driver's part of device suspend already.  Moreover, it may be
harmful, because the ->runtime_suspend callback may want to
access the device which is partially suspended at that point
and may not be responsive.  Also, system-wide PM callbacks may
have been run already (in the previous phases of the system
transition under way) for the device's parent or for its supplier
devices (if any) and the device may not be accessible because of
that.

There also is no reason to do (3), because genpd_finish_suspend()
will repeat it anyway, and (4) potentially causes confusion to ensue
during the subsequent system transition to the working state.

Consider pm_runtime_force_resume() in genpd_resume_noirq() now.
It runs genpd_runtime_resume() for all devices with runtime PM
status set to "suspended", which includes all of the devices
whose runtime PM status was changed by pm_runtime_force_suspend()
before and may include some devices already suspended when the
pm_runtime_force_suspend() was running, which may be confusing.  The
genpd_runtime_resume() first tries to power up the domain, which
(again) is pointless, because genpd_resume_noirq() has done that
already.  Then, it "starts" the device and runs the ->runtime_resume
callback (from the driver, say) for it.  If all is well, the device
is left with the runtime PM status set to "active".

Unfortunately, running the driver's ->runtime_resume callback
before its system-wide PM callbacks and possibly before some
system-wide PM callbacks of the parent device's driver (let
alone supplier drivers) is asking for trouble, especially if
the device had been suspended before pm_runtime_force_suspend()
ran previously or if the callbacks in question expect to be run
back-to-back with their suspend-side counterparts.  It also should
not be necessary, because the system-wide PM driver callbacks that
will be invoked for the device subsequently should take care of
resuming it just fine.

[Running the driver's ->runtime_resume callback in the "noirq"
phase of the transition to the working state may be problematic
even for devices whose drivers do use pm_runtime_force_resume()
in (or as) their system-wide PM callbacks if they have suppliers
other than their parents, because it may cause the supplier to
be resumed after the consumer in some cases.]

Because of the above, modify genpd as follows:

 1. Change genpd_finish_suspend() to only "stop" devices with
    runtime PM status set to "active" (without invoking runtime PM
    callbacks for them, changing their runtime PM status and so on).

    That doesn't change the handling of devices whose drivers use
    pm_runtime_force_suspend/resume() in (or as) their system-wide
    PM callbacks and addresses the issues described above for the
    other devices.

 2. Change genpd_resume_noirq() to only "start" devices with
    runtime PM status set to "active" (without invoking runtime PM
    callbacks for them, changing their runtime PM status and so on).

    Again, that doesn't change the handling of devices whose drivers
    use pm_runtime_force_suspend/resume() in (or as) their system-wide
    PM callbacks and addresses the described issues for the other
    devices.  Devices with runtime PM status set to "suspended"
    are not started with the assumption that they will be resumed
    later, either by pm_runtime_force_resume() or via runtime PM.

 3. Change genpd_restore_noirq() to follow genpd_resume_noirq().

    That causes devices already suspended before hibernation to be
    left alone (which also is the case without the change) and
    avoids running the ->runtime_resume driver callback too early
    for the other devices.

 4. Change genpd_freeze_noirq() and genpd_thaw_noirq() in accordance
    with the above modifications.

Fixes: 122a22377a (PM / Domains: Stop/start devices during system PM suspend/resume in genpd)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
2018-01-15 01:33:37 +01:00
Ulf Hansson 0026cef067 PM / wakeup: Print warn if device gets enabled as wakeup source during sleep
In general, wakeup settings are not supposed to be changed during any of
the system wide PM phases. The reason is simply that it would break
guarantees provided by the PM core, to properly act on active wakeup
sources.

However, there are exceptions to when, in particular, disabling a device as
wakeup source makes sense. For example, in cases when a driver realizes
that its device is dead during system suspend. For these scenarios, we
don't need to care about acting on the wakeup source correctly, because a
dead device shouldn't deliver wakeup signals.

To this reasoning and to help users to properly manage wakeup settings,
let's print a warning in cases someone calls device_wakeup_enable() during
system sleep.

Suggested-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Message to be printed ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-11 18:50:54 +01:00
Ulf Hansson a935424bb6 PM / domains: Don't skip driver's ->suspend|resume_noirq() callbacks
Commit 10da65423f (PM / Domains: Call driver's noirq callbacks)
started to respect driver's noirq callbacks, but while doing that it
also introduced a few potential problems.

More precisely, in genpd_finish_suspend() and genpd_resume_noirq()
the noirq callbacks at the driver level should be invoked, no matter
of whether dev->power.wakeup_path is set or not.

Additionally, the commit in question also made genpd_resume_noirq()
to ignore the return value from pm_runtime_force_resume().

Let's fix both these issues!

Fixes: 10da65423f (PM / Domains: Call driver's noirq callbacks)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-11 01:57:44 +01:00
Ulf Hansson 0a99d767a9 PM / core: Propagate wakeup_path status flag in __device_suspend_late()
Currently the wakeup_path status flag becomes propagated from a child
device to its parent device at __device_suspend(). This allows a driver
dealing with a parent device to act on the flag from its ->suspend()
callback.

However, in situations when the wakeup_path status flag needs to be set
from a ->suspend_late() callback, its value doesn't get propagated to the
parent by the PM core. Let's address this limitation, by also propagating
the flag at __device_suspend_late().

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-10 13:13:57 +01:00
Ulf Hansson c23bd3877b PM / core: Re-structure code for clearing the direct_complete flag
To make the code more consistent, let's clear the parent's direct_complete
flag along with clearing it for suppliers, instead of as currently, when
propagating the wakeup_path flag to parents.

While changing this, let's take the opportunity to rename the affected
internal functions, to make them self-explanatory. Like this:

dpm_clear_suppliers_direct_complete -> dpm_clear_superiors_direct_complete
dpm_propagate_to_parent -> dpm_propagate_wakeup_to_parent

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-10 13:13:56 +01:00
Ulf Hansson 8512220c57 PM / core: Assign the wakeup_path status flag in __device_prepare()
The PM core in the device_prepare() phase, resets the wakeup_path status
flag to the value of device_may_wakeup(). This means if a ->prepare() or a
->suspend() callback for the device would update the device's wakeup
setting, this doesn't become reflected in the wakeup_path status flag.

In general this isn't a problem, because wakeup settings are not supposed
to be changed (via for example calling device_set_wakeup_enable()) during
any system wide suspend/resume phase.  Nevertheless there are some users,
which can be considered as legacy, that don't conform to this behaviour.

These legacy cases should be corrected, however until that is done, let's
address the issue from the PM core, by moving the assignment of the
wakeup_path status flag to the __device_suspend() phase and after the
->suspend() callback has been invoked.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-09 13:09:16 +01:00
Rafael J. Wysocki 7bf4e594c2 PM / wakeup: Do not fail dev_pm_attach_wake_irq() unnecessarily
Returning an error code from dev_pm_attach_wake_irq() if
device_wakeup_attach_irq() called by it returns an error is
pointless, because the wakeup source used by it may be deleted
by user space via sysfs at any time and in particular right after
dev_pm_attach_wake_irq() has returned.  Moreover, it requires
the callers of dev_pm_attach_wake_irq() to create that wakeup
source via device_wakeup_enable() upfront, but that obviously is
racy with respect to the sysfs-based manipulations of it.

To avoid the race, modify device_wakeup_attach_irq() to check
that the wakeup source it is going to use is there (and return
early otherwise), make it void (as it cannot fail after that
change) and make dev_pm_attach_wake_irq() simply call it for
the device unconditionally.

Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-09 13:09:16 +01:00
Rafael J. Wysocki 32bfa56ac1 PM / core: Direct DPM_FLAG_LEAVE_SUSPENDED handling
Make the PM core handle DPM_FLAG_LEAVE_SUSPENDED directly for
devices whose "noirq", "late" and "early" driver callbacks are
invoked directly by it.

Namely, make it skip all of the system-wide resume callbacks for
such devices with DPM_FLAG_LEAVE_SUSPENDED set if they are in
runtime suspend during the "noirq" phase of system-wide suspend
(or analogous) transitions or the system transition under way is
a proper suspend (rather than anything related to hibernation) and
the device's wakeup settings are compatible with runtime PM (that
is, the device cannot generate wakeup signals at all or it is
allowed to wake up the system from sleep).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-03 00:30:00 +01:00
Rafael J. Wysocki 75e94645fc PM / core: Direct DPM_FLAG_SMART_SUSPEND optimization
Make the PM core avoid invoking the "late" and "noirq" system-wide
suspend (or analogous) callbacks provided by device drivers directly
for devices with DPM_FLAG_SMART_SUSPEND set that are in runtime
suspend during the "late" and "noirq" phases of system-wide suspend
(or analogous) transitions.  That is only done for devices without
any middle-layer "late" and "noirq" suspend callbacks (to avoid
confusing the middle layer if there is one).

The underlying observation is that runtime PM is disabled for devices
during the "late" and "noirq" system-wide suspend phases, so if they
remain in runtime suspend from the "late" phase forward, it doesn't
make sense to invoke the "late" and "noirq" callbacks provided by
the drivers for them (arguably, the device is already suspended and
in the right state).  Thus, if the remaining driver suspend callbacks
are to be invoked directly by the core, they can be skipped.

This change really makes it possible for, say, platform device
drivers to re-use runtime PM suspend and resume callbacks by
pointing ->suspend_late and ->resume_early, respectively (and
possibly the analogous hibernation-related callback pointers too),
to them without adding any extra "is the device already suspended?"
type of checks to the callback routines, as long as they will be
invoked directly by the core.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-03 00:29:55 +01:00
Rafael J. Wysocki 4fa3061a68 PM / core: Add helpers for subsystem callback selection
Add helper routines to find and return a suitable subsystem callback
during the "noirq" phases of system suspend/resume (or analogous)
transitions as well as during the "late" phase of system suspend and
the "early" phase of system resume (or analogous) transitions.

The helpers will be called from additional sites going forward.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
2018-01-03 00:29:48 +01:00
Rafael J. Wysocki 9dbc64a5d5 PM / wakeup: Drop redundant check from device_init_wakeup()
Since device_wakeup_disable() checks the device's power.can_wakeup
flag, device_init_wakeup() doesn't need to do that before calling it,
so drop that redundant check from device_init_wakeup().

No intentional changes in functionality.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2018-01-03 00:29:30 +01:00
Rafael J. Wysocki d97c2e0d63 PM / wakeup: Drop redundant check from device_set_wakeup_enable()
Since both device_wakeup_enable() and device_wakeup_disable() check
if dev is not NULL and whether or not power.can_wakeup is set for it,
device_set_wakeup_enable() doesn't have to do that, so drop that
check from it.

No intentional changes in functionality.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2018-01-03 00:28:39 +01:00
Brian Norris 86ddd2db1f PM / wakeup: only recommend "call"ing device_init_wakeup() once
I'll admit admit it: I've written bad driver code that tries to
configure a device's wake IRQ without having called device_init_wakeup()
first. But do you really have to ask ask me twice?

Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-19 02:45:06 +01:00
Rafael J. Wysocki c51a024e39 Merge back PM core material for v4.16. 2017-12-16 02:05:48 +01:00
Rafael J. Wysocki 34fb8f0ba9 PM / core: Use dev_pm_skip_next_resume_phases() internally
Make the PM core call dev_pm_skip_next_resume_phases() to skip the
"early resume" and "resume" phases of system-wide transitions to the
working state for a given device instead of clearing the relevant
status bits for it directly.

No intentional changes in functionality.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-12-13 01:45:06 +01:00
Sergey Senozhatsky 7e6a70a578 PM / core: remove unneeded kallsyms include
The file was converted from print_fn_descriptor_symbol()
to %pF some time ago (c80cfb0406 "vsprintf: use new
vsprintf symbolic function pointer format"). kallsyms does
not seem to be needed anymore.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-13 01:38:57 +01:00
Geert Uytterhoeven 001d50c9a1 PM / Domains: Remove obsolete "samsung,power-domain" check
Currently the generic PM Domain code code checks for the presence of
both (generic) "power-domains" and (Samsung Exynos legacy)
"samsung,power-domain" properties in all device tree nodes representing
devices.

There are two issues with this:
  1. This imposes a small boot-time penalty on all platforms using DT,
  2. Platform-specific checks do not really belong in core framework
     code.

Remove the platform-specific check, as the last user of
"samsung,power-domain" was removed in commit 46dcf0ff0d ("ARM:
dts: exynos: Remove exynos4415.dtsi").  All other users were converted
before in commit 0da6587041 ("ARM: dts: convert to generic power
domain bindings for exynos DT").

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-13 01:34:47 +01:00
Rafael J. Wysocki 3487972d7f PM / sleep: Avoid excess pm_runtime_enable() calls in device_resume()
Middle-layer code doing suspend-time optimizations for devices with
the DPM_FLAG_SMART_SUSPEND flag set (currently, the PCI bus type and
the ACPI PM domain) needs to make the core skip ->thaw_early and
->thaw callbacks for those devices in some cases and it sets the
power.direct_complete flag for them for this purpose.

However, it turns out that setting power.direct_complete outside of
the PM core is a bad idea as it triggers an excess invocation of
pm_runtime_enable() in device_resume().

For this reason, provide a helper to clear power.is_late_suspended
and power.is_suspended to be invoked by the middle-layer code in
question instead of setting power.direct_complete and make that code
call the new helper.

Fixes: c4b65157ae (PCI / PM: Take SMART_SUSPEND driver flag into account)
Fixes: 05087360fd (ACPI / PM: Take SMART_SUSPEND driver flag into account)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2017-12-11 14:32:56 +01:00
Rafael J. Wysocki 4f86a21fae Merge back earlier PM core material for v4.16. 2017-12-11 14:25:48 +01:00
Ulf Hansson 1172ee3125 PM / core: Re-factor some code dealing with parents in __device_suspend()
Let's make the code a bit more readable by moving some of the code, which
deals with adjustments for parent devices in __device_suspend(), into its
own function.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-05 01:59:58 +01:00
Andy Shevchenko 47acbd77e6 PM / sysfs: Convert to use DEVICE_ATTR_RO / DEVICE_ATTR_RW
Use DEVICE_ATTR_RO() and DEVICE_ATTR_RW() macros instead of
open coding them.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-05 01:59:57 +01:00
Andy Shevchenko f0e6d9f164 PM / sysfs: Remove redundant 'else' keyword.
There is no need to use 'else' if in main branch 'return' is present.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-05 01:59:57 +01:00
Andy Shevchenko 325c4b3b81 PM / sysfs: Convert to use sysfs_streq()
...instead of custom approach.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-05 01:59:56 +01:00
Rafael J. Wysocki 31eb743180 PM / runtime: Fix handling of suppliers with disabled runtime PM
Prevent rpm_get_suppliers() from returning an error code if runtime
PM is disabled for one or more of the supplier devices it wants to
runtime-resume, so as to make runtime PM work for devices with links
to suppliers that don't use runtime PM (such links may be created
during device enumeration even before it is known whether or not
runtime PM will be enabled for the devices in question, for example).

Fixes: 21d5c57b37 (PM / runtime: Use device links)
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Adrian Hunter <adrian.hunter@intel.com>
2017-12-04 15:12:07 +01:00
Rafael J. Wysocki 0d4b54c6fe PM / core: Add LEAVE_SUSPENDED driver flag
Define and document a new driver flag, DPM_FLAG_LEAVE_SUSPENDED, to
instruct the PM core and middle-layer (bus type, PM domain, etc.)
code that it is desirable to leave the device in runtime suspend
after system-wide transitions to the working state (for example,
the device may be slow to resume and it may be better to avoid
resuming it right away).

Generally, the middle-layer code involved in the handling of the
device is expected to indicate to the PM core whether or not the
device may be left in suspend with the help of the device's
power.may_skip_resume status bit.  That has to happen in the "noirq"
phase of the preceding system suspend (or analogous) transition.
The middle layer is then responsible for handling the device as
appropriate in its "noirq" resume callback which is executed
regardless of whether or not the device may be left suspended, but
the other resume callbacks (except for ->complete) will be skipped
automatically by the core if the device really can be left in
suspend.

The additional power.must_resume status bit introduced for the
implementation of this mechanisn is used internally by the PM core
to track the requirement to resume the device (which may depend on
its children etc).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-11-27 01:20:59 +01:00
Kees Cook 841b86f328 treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts
With all callbacks converted, and the timer callback prototype
switched over, the TIMER_FUNC_TYPE cast is no longer needed,
so remove it. Conversion was done with the following scripts:

    perl -pi -e 's|\(TIMER_FUNC_TYPE\)||g' \
        $(git grep TIMER_FUNC_TYPE | cut -d: -f1 | sort -u)

    perl -pi -e 's|\(TIMER_DATA_TYPE\)||g' \
        $(git grep TIMER_DATA_TYPE | cut -d: -f1 | sort -u)

The now unused macros are also dropped from include/linux/timer.h.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 16:35:54 -08:00
Rafael J. Wysocki f8817f61e8 PM / runtime: Drop children check from __pm_runtime_set_status()
The check for "active" children in __pm_runtime_set_status(), when
trying to set the parent device status to "suspended", doesn't
really make sense, because in fact it is not invalid to set the
status of a device with runtime PM disabled to "suspended" in any
case.  It is invalid to enable runtime PM for a device with its
status set to "suspended" while its child_count reference counter
is nonzero, but the check in __pm_runtime_set_status() doesn't
really cover that situation.

For this reason, drop the children check from __pm_runtime_set_status()
and add a check against child_count reference counters of "suspended"
devices to pm_runtime_enable().

Fixes: a8636c8964 (PM / Runtime: Don't allow to suspend a device with an active child)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Johan Hovold <johan@kernel.org>
2017-11-16 22:51:22 +01:00
Linus Torvalds bd2cd7d5a8 Power management updates for v4.15-rc1
- Relocate the OPP (Operating Performance Points) framework to its
    own directory under drivers/ and add support for power domain
    performance states to it (Viresh Kumar).
 
  - Modify the PM core, the PCI bus type and the ACPI PM domain to
    support power management driver flags allowing device drivers to
    specify their capabilities and preferences regarding the handling
    of devices with enabled runtime PM during system suspend/resume
    and clean up that code somewhat (Rafael Wysocki, Ulf Hansson).
 
  - Add frequency-invariant accounting support to the task scheduler
    on ARM and ARM64 (Dietmar Eggemann).
 
  - Fix PM QoS device resume latency framework to prevent "no
    restriction" requests from overriding requests with specific
    requirements and drop the confusing PM_QOS_FLAG_REMOTE_WAKEUP
    device PM QoS flag (Rafael Wysocki).
 
  - Drop legacy class suspend/resume operations from the PM core
    and drop legacy bus type suspend and resume callbacks from
    ARM/locomo (Rafael Wysocki).
 
  - Add min/max frequency support to devfreq and clean it up
    somewhat (Chanwoo Choi).
 
  - Rework wakeup support in the generic power domains (genpd)
    framework and update some of its users accordingly (Geert
    Uytterhoeven).
 
  - Convert timers in the PM core to use timer_setup() (Kees Cook).
 
  - Add support for exposing the SLP_S0 (Low Power S0 Idle)
    residency counter based on the LPIT ACPI table on Intel
    platforms (Srinivas Pandruvada).
 
  - Add per-CPU PM QoS resume latency support to the ladder cpuidle
    governor (Ramesh Thomas).
 
  - Fix a deadlock between the wakeup notify handler and the
    notifier removal in the ACPI core (Ville Syrjälä).
 
  - Fix a cpufreq schedutil governor issue causing it to use
    stale cached frequency values sometimes (Viresh Kumar).
 
  - Fix an issue in the system suspend core support code causing
    wakeup events detection to fail in some cases (Rajat Jain).
 
  - Fix the generic power domains (genpd) framework to prevent
    the PM core from using the direct-complete optimization with
    it as that is guaranteed to fail (Ulf Hansson).
 
  - Fix a minor issue in the cpuidle core and clean it up a bit
    (Gaurav Jindal, Nicholas Piggin).
 
  - Fix and clean up the intel_idle and ARM cpuidle drivers (Jason
    Baron, Len Brown, Leo Yan).
 
  - Fix a couple of minor issues in the OPP framework and clean it
    up (Arvind Yadav, Fabio Estevam, Sudeep Holla, Tobias Jordan).
 
  - Fix and clean up some cpufreq drivers and fix a minor issue in
    the cpufreq statistics code (Arvind Yadav, Bhumika Goyal, Fabio
    Estevam, Gautham Shenoy, Gustavo Silva, Marek Szyprowski, Masahiro
    Yamada, Robert Jarzmik, Zumeng Chen).
 
  - Fix minor issues in the system suspend and hibernation core, in
    power management documentation and in the AVS (Adaptive Voltage
    Scaling) framework (Helge Deller, Himanshu Jha, Joe Perches,
    Rafael Wysocki).
 
  - Fix some issues in the cpupower utility and document that Shuah
    Khan is going to maintain it going forward (Prarit Bhargava,
    Shuah Khan).
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Merge tag 'pm-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "There are no real big ticket items here this time.

  The most noticeable change is probably the relocation of the OPP
  (Operating Performance Points) framework to its own directory under
  drivers/ as it has grown big enough for that. Also Viresh is now going
  to maintain it and send pull requests for it to me, so you will see
  this change in the git history going forward (but still not right
  now).

  Another noticeable set of changes is the modifications of the PM core,
  the PCI subsystem and the ACPI PM domain to allow of more integration
  between system-wide suspend/resume and runtime PM. For now it's just a
  way to avoid resuming devices from runtime suspend unnecessarily
  during system suspend (if the driver sets a flag to indicate its
  readiness for that) and in the works is an analogous mechanism to
  allow devices to stay suspended after system resume.

  In addition to that, we have some changes related to supporting
  frequency-invariant CPU utilization metrics in the scheduler and in
  the schedutil cpufreq governor on ARM and changes to add support for
  device performance states to the generic power domains (genpd)
  framework.

  The rest is mostly fixes and cleanups of various sorts.

  Specifics:

   - Relocate the OPP (Operating Performance Points) framework to its
     own directory under drivers/ and add support for power domain
     performance states to it (Viresh Kumar).

   - Modify the PM core, the PCI bus type and the ACPI PM domain to
     support power management driver flags allowing device drivers to
     specify their capabilities and preferences regarding the handling
     of devices with enabled runtime PM during system suspend/resume and
     clean up that code somewhat (Rafael Wysocki, Ulf Hansson).

   - Add frequency-invariant accounting support to the task scheduler on
     ARM and ARM64 (Dietmar Eggemann).

   - Fix PM QoS device resume latency framework to prevent "no
     restriction" requests from overriding requests with specific
     requirements and drop the confusing PM_QOS_FLAG_REMOTE_WAKEUP
     device PM QoS flag (Rafael Wysocki).

   - Drop legacy class suspend/resume operations from the PM core and
     drop legacy bus type suspend and resume callbacks from ARM/locomo
     (Rafael Wysocki).

   - Add min/max frequency support to devfreq and clean it up somewhat
     (Chanwoo Choi).

   - Rework wakeup support in the generic power domains (genpd)
     framework and update some of its users accordingly (Geert
     Uytterhoeven).

   - Convert timers in the PM core to use timer_setup() (Kees Cook).

   - Add support for exposing the SLP_S0 (Low Power S0 Idle) residency
     counter based on the LPIT ACPI table on Intel platforms (Srinivas
     Pandruvada).

   - Add per-CPU PM QoS resume latency support to the ladder cpuidle
     governor (Ramesh Thomas).

   - Fix a deadlock between the wakeup notify handler and the notifier
     removal in the ACPI core (Ville Syrjälä).

   - Fix a cpufreq schedutil governor issue causing it to use stale
     cached frequency values sometimes (Viresh Kumar).

   - Fix an issue in the system suspend core support code causing wakeup
     events detection to fail in some cases (Rajat Jain).

   - Fix the generic power domains (genpd) framework to prevent the PM
     core from using the direct-complete optimization with it as that is
     guaranteed to fail (Ulf Hansson).

   - Fix a minor issue in the cpuidle core and clean it up a bit (Gaurav
     Jindal, Nicholas Piggin).

   - Fix and clean up the intel_idle and ARM cpuidle drivers (Jason
     Baron, Len Brown, Leo Yan).

   - Fix a couple of minor issues in the OPP framework and clean it up
     (Arvind Yadav, Fabio Estevam, Sudeep Holla, Tobias Jordan).

   - Fix and clean up some cpufreq drivers and fix a minor issue in the
     cpufreq statistics code (Arvind Yadav, Bhumika Goyal, Fabio
     Estevam, Gautham Shenoy, Gustavo Silva, Marek Szyprowski, Masahiro
     Yamada, Robert Jarzmik, Zumeng Chen).

   - Fix minor issues in the system suspend and hibernation core, in
     power management documentation and in the AVS (Adaptive Voltage
     Scaling) framework (Helge Deller, Himanshu Jha, Joe Perches, Rafael
     Wysocki).

   - Fix some issues in the cpupower utility and document that Shuah
     Khan is going to maintain it going forward (Prarit Bhargava, Shuah
     Khan)"

* tag 'pm-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (88 commits)
  tools/power/cpupower: add libcpupower.so.0.0.1 to .gitignore
  tools/power/cpupower: Add 64 bit library detection
  intel_idle: Graceful probe failure when MWAIT is disabled
  cpufreq: schedutil: Reset cached_raw_freq when not in sync with next_freq
  freezer: Fix typo in freezable_schedule_timeout() comment
  PM / s2idle: Clear the events_check_enabled flag
  cpufreq: stats: Handle the case when trans_table goes beyond PAGE_SIZE
  cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const
  cpufreq: arm_big_little: make function arguments and structure pointer const
  cpuidle: Avoid assignment in if () argument
  cpuidle: Clean up cpuidle_enable_device() error handling a bit
  ACPI / PM: Fix acpi_pm_notifier_lock vs flush_workqueue() deadlock
  PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare()
  cpuidle: ladder: Add per CPU PM QoS resume latency support
  PM / QoS: Fix device resume latency framework
  PM / domains: Rework governor code to be more consistent
  PM / Domains: Remove gpd_dev_ops.active_wakeup() callback
  soc: rockchip: power-domain: Use GENPD_FLAG_ACTIVE_WAKEUP
  soc: mediatek: Use GENPD_FLAG_ACTIVE_WAKEUP
  ARM: shmobile: pm-rmobile: Use GENPD_FLAG_ACTIVE_WAKEUP
  ...
2017-11-13 19:43:50 -08:00
Linus Torvalds 2bcc673101 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "Yet another big pile of changes:

   - More year 2038 work from Arnd slowly reaching the point where we
     need to think about the syscalls themself.

   - A new timer function which allows to conditionally (re)arm a timer
     only when it's either not running or the new expiry time is sooner
     than the armed expiry time. This allows to use a single timer for
     multiple timeout requirements w/o caring about the first expiry
     time at the call site.

   - A new NMI safe accessor to clock real time for the printk timestamp
     work. Can be used by tracing, perf as well if required.

   - A large number of timer setup conversions from Kees which got
     collected here because either maintainers requested so or they
     simply got ignored. As Kees pointed out already there are a few
     trivial merge conflicts and some redundant commits which was
     unavoidable due to the size of this conversion effort.

   - Avoid a redundant iteration in the timer wheel softirq processing.

   - Provide a mechanism to treat RTC implementations depending on their
     hardware properties, i.e. don't inflict the write at the 0.5
     seconds boundary which originates from the PC CMOS RTC to all RTCs.
     No functional change as drivers need to be updated separately.

   - The usual small updates to core code clocksource drivers. Nothing
     really exciting"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (111 commits)
  timers: Add a function to start/reduce a timer
  pstore: Use ktime_get_real_fast_ns() instead of __getnstimeofday()
  timer: Prepare to change all DEFINE_TIMER() callbacks
  netfilter: ipvs: Convert timers to use timer_setup()
  scsi: qla2xxx: Convert timers to use timer_setup()
  block/aoe: discover_timer: Convert timers to use timer_setup()
  ide: Convert timers to use timer_setup()
  drbd: Convert timers to use timer_setup()
  mailbox: Convert timers to use timer_setup()
  crypto: Convert timers to use timer_setup()
  drivers/pcmcia: omap1: Fix error in automated timer conversion
  ARM: footbridge: Fix typo in timer conversion
  drivers/sgi-xp: Convert timers to use timer_setup()
  drivers/pcmcia: Convert timers to use timer_setup()
  drivers/memstick: Convert timers to use timer_setup()
  drivers/macintosh: Convert timers to use timer_setup()
  hwrng/xgene-rng: Convert timers to use timer_setup()
  auxdisplay: Convert timers to use timer_setup()
  sparc/led: Convert timers to use timer_setup()
  mips: ip22/32: Convert timers to use timer_setup()
  ...
2017-11-13 17:56:58 -08:00
Rafael J. Wysocki 1efef68262 Merge branch 'pm-core'
* pm-core:
  ACPI / PM: Take SMART_SUSPEND driver flag into account
  PCI / PM: Take SMART_SUSPEND driver flag into account
  PCI / PM: Drop unnecessary invocations of pcibios_pm_ops callbacks
  PM / core: Add SMART_SUSPEND driver flag
  PCI / PM: Use the NEVER_SKIP driver flag
  PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags
  PM / core: Convert timers to use timer_setup()
  PM / core: Fix kerneldoc comments of four functions
  PM / core: Drop legacy class suspend/resume operations
2017-11-13 01:41:26 +01:00
Rafael J. Wysocki 05d658b5b5 Merge branch 'pm-sleep'
* pm-sleep:
  freezer: Fix typo in freezable_schedule_timeout() comment
  PM / s2idle: Clear the events_check_enabled flag
  PM / sleep: Remove pm_complete_with_resume_check()
  PM: ARM: locomo: Drop suspend and resume bus type callbacks
  PM: Use a more common logging style
  PM: Document rules on using pm_runtime_resume() in system suspend callbacks
2017-11-13 01:41:20 +01:00
Rafael J. Wysocki 28da43956b Merge branches 'pm-cpufreq-sched' and 'pm-opp'
* pm-cpufreq-sched:
  cpufreq: schedutil: Reset cached_raw_freq when not in sync with next_freq

* pm-opp:
  PM / OPP: Add dev_pm_opp_{un}register_get_pstate_helper()
  PM / OPP: Support updating performance state of device's power domain
  PM / OPP: add missing of_node_put() for of_get_cpu_node()
  PM / OPP: Rename dev_pm_opp_register_put_opp_helper()
  PM / OPP: Add missing of_node_put(np)
  PM / OPP: Move error message to debug level
  PM / OPP: Use snprintf() to avoid kasprintf() and kfree()
  PM / OPP: Move the OPP directory out of power/
2017-11-13 01:40:52 +01:00
Rafael J. Wysocki 4762573b93 Merge branch 'pm-qos'
* pm-qos:
  PM / QoS: Fix device resume latency framework
  PM / QoS: Drop PM_QOS_FLAG_REMOTE_WAKEUP
2017-11-13 01:33:48 +01:00
Rafael J. Wysocki 29aaf90875 Merge branch 'pm-domains'
* pm-domains:
  PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare()
  PM / domains: Rework governor code to be more consistent
  PM / Domains: Remove gpd_dev_ops.active_wakeup() callback
  soc: rockchip: power-domain: Use GENPD_FLAG_ACTIVE_WAKEUP
  soc: mediatek: Use GENPD_FLAG_ACTIVE_WAKEUP
  ARM: shmobile: pm-rmobile: Use GENPD_FLAG_ACTIVE_WAKEUP
  PM / Domains: Allow genpd users to specify default active wakeup behavior
  PM / Domains: Add support to select performance-state of domains
  PM / Domains: Rename genpd internals from pm_genpd_* to genpd_*
2017-11-13 01:33:35 +01:00
Ulf Hansson 5241ab40f6 PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare()
During system-wide PM, genpd relies on its PM callbacks to be invoked for
all its attached devices, as to deal with powering off/on the PM domain. In
other words, genpd is not compatible with the direct_complete path, if
executed by the PM core for any of its attached devices.

However, when genpd's ->prepare() callback invokes pm_generic_prepare(), it
does not take into account that it may return 1. Instead it treats that as
an error internally and expects the PM core to abort the prepare phase and
roll back. This leads to genpd not properly powering on/off the PM domain,
because its internal counters gets wrongly balanced.

To fix the behaviour, allow drivers to return 1 from their ->prepare()
callbacks, but let's return 0 from genpd's ->prepare() callback in such
case, as that prevents the PM core from running the direct_complete path
for the device.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-11-08 12:16:57 +01:00
Rafael J. Wysocki 0759e80b84 PM / QoS: Fix device resume latency framework
The special value of 0 for device resume latency PM QoS means
"no restriction", but there are two problems with that.

First, device resume latency PM QoS requests with 0 as the
value are always put in front of requests with positive
values in the priority lists used internally by the PM QoS
framework, causing 0 to be chosen as an effective constraint
value.  However, that 0 is then interpreted as "no restriction"
effectively overriding the other requests with specific
restrictions which is incorrect.

Second, the users of device resume latency PM QoS have no
way to specify that *any* resume latency at all should be
avoided, which is an artificial limitation in general.

To address these issues, modify device resume latency PM QoS to
use S32_MAX as the "no constraint" value and 0 as the "no
latency at all" one and rework its users (the cpuidle menu
governor, the genpd QoS governor and the runtime PM framework)
to follow these changes.

Also add a special "n/a" value to the corresponding user space I/F
to allow user space to indicate that it cannot accept any resume
latencies at all for the given device.

Fixes: 85dc0b8a40 (PM / QoS: Make it possible to expose PM QoS latency constraints)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=197323
Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-11-08 12:14:51 +01:00
Rafael J. Wysocki 31f18230e4 Merge branch 'pm-domains' into pm-qos 2017-11-08 12:14:38 +01:00
Rafael J. Wysocki 704d2ce660 PM / domains: Rework governor code to be more consistent
The genpd governor currently uses negative PM QoS values to indicate
the "no suspend" condition and 0 as "no restriction", but it doesn't
use them consistently.  Moreover, it tries to refresh QoS values for
already suspended devices in a quite questionable way.

For the above reasons, rework it to be a bit more consistent.

First off, note that dev_pm_qos_read_value() in
dev_update_qos_constraint() and __default_power_down_ok() is
evaluated for devices in suspend.  Moreover, that only happens if the
effective_constraint_ns value for them is negative (meaning "no
suspend").  It is not evaluated in any other cases, so effectively
the QoS values are only updated for devices in suspend that should
not have been suspended in the first place.  In all of the other
cases, the QoS values taken into account are the effective ones from
the time before the device has been suspended, so generally devices
need to be resumed and suspended again for new QoS values to take
effect anyway.  Thus evaluating dev_update_qos_constraint() in
those two places doesn't make sense at all, so drop it.

Second, initialize effective_constraint_ns to 0 ("no constraint")
rather than to (-1) ("no suspend"), which makes more sense in
general and in case effective_constraint_ns is never updated
(the device is in suspend all the time or it is never suspended)
it doesn't affect the device's parent and so on.

Finally, rework default_suspend_ok() to explicitly handle the
"no restriction" and "no suspend" special cases.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-11-08 12:13:13 +01:00
Geert Uytterhoeven d0af45f1f6 PM / Domains: Remove gpd_dev_ops.active_wakeup() callback
There are no more users left of the gpd_dev_ops.active_wakeup()
callback.  All have been converted to GENPD_FLAG_ACTIVE_WAKEUP.
Hence remove the callback.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-11-08 01:00:48 +01:00