If dev_pm_attach_wake_irq() fails, the device's power.wakeirq field
should not be set to point to the struct wake_irq passed to that
function, as that object will be freed going forward.

For this reason, make dev_pm_attach_wake_irq() first call
device_wakeup_attach_irq() and only set the device's power.wakeirq
field if that's successful.

That requires device_wakeup_attach_irq() to be called under the
device's power.lock lock, but since dev_pm_attach_wake_irq() is
the only caller of it, the requisite changes are easy to make.

Fixes: 4990d4fe (PM / Wakeirq: Add automated device wake IRQ handling)
Reported-by: NFelipe Balbi <balbi@ti.com>
Tested-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Currently the con_id of the acquired clock is printed for debugging
purposes.  But in several cases, the con_id is NULL, which doesn't
provide much debugging information when printed.  These cases are:
  - When explicitly passing a NULL con_id (which means the first clock
    tied to the device, if available),
  - When not using pm_clk_add(), but pm_clk_add_clk() (which takes a
    "struct clk *" directly).

Hence print the actual clock name in addition to (and not instead of;
thanks Grygorii Strashko!) the con_id.

Note that the clock name is not available with legacy clock frameworks,
and the hex pointer address will be printed instead.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NGrygorii Strashko <grygorii.strashko@linaro.org>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Move the trace_device_pm_callback locations for dpm_prepare and dpm_complete
to encompass the attempt to capture the device mutex prior to callback. This
is needed by analyze_suspend to identify gaps in the trace output caused by
the delay in locking the mutex for a device.
Signed-off-by: NTodd Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Turns out we can automate the handling for the device_may_wakeup()
quite a bit by using the kernel wakeup source list as suggested
by Rafael J. Wysocki <rjw@rjwysocki.net>.

And as some hardware has separate dedicated wake-up interrupt
in addition to the IO interrupt, we can automate the handling by
adding a generic threaded interrupt handler that just calls the
device PM runtime to wake up the device.

This allows dropping code from device drivers as we currently
are doing it in multiple ways, and often wrong.

For most drivers, we should be able to drop the following
boilerplate code from runtime_suspend and runtime_resume
functions:

	...
	device_init_wakeup(dev, true);
	...
	if (device_may_wakeup(dev))
		enable_irq_wake(irq);
	...
	if (device_may_wakeup(dev))
		disable_irq_wake(irq);
	...
	device_init_wakeup(dev, false);
	...

We can replace it with just the following init and exit
time code:

	...
	device_init_wakeup(dev, true);
	dev_pm_set_wake_irq(dev, irq);
	...
	dev_pm_clear_wake_irq(dev);
	device_init_wakeup(dev, false);
	...

And for hardware with dedicated wake-up interrupts:

	...
	device_init_wakeup(dev, true);
	dev_pm_set_dedicated_wake_irq(dev, irq);
	...
	dev_pm_clear_wake_irq(dev);
	device_init_wakeup(dev, false);
	...
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

If we don't update last_busy in rpm_resume, devices can go back
to sleep immediately after resume. This happens at least in
cases where the device has been powered off and does not have
any interrupt pending until there's something in the FIFO.
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

In the final iteration of commit 245bd6f6 ("PM / clock_ops: Add
pm_clk_add_clk()"), a refcount increment was added by Grygorii Strashko.
However, the accompanying IS_ERR() check operates on the wrong clock
pointer, which is always zero at this point, i.e. not an error.
This may lead to a NULL pointer dereference later, when __clk_get()
tries to dereference an error pointer.

Check the passed clock pointer instead to fix this.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Fixes: 245bd6f6 ("PM / clock_ops: Add pm_clk_add_clk()")
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

After a wakeup_source is destroyed, we lost all information such as how
long this wakeup_source has been active. Add a dummy wakeup_source to
record such info.
Signed-off-by: NJin Qian <jinqian@android.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Most users of PM clocks do the extact same things in the runtime
suspend/resume callbacks. Provide them USE_PM_CLK_RUNTIME_OPS so
as to avoid/remove boilerplate code.
Signed-off-by: NRajendra Nayak <rnayak@codeaurora.org>
Reviewed-by: NKevin Hilman <khilman@linaro.org>
Acked-by: NSantosh Shilimkar <ssantosh@kernel.org>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

A rogue wakeup source not registered in wakeup_sources list is not visible
from wakeup_sources_stats_show. Check if the wakeup source is registered
properly by looking at the timer struct.
Signed-off-by: NJin Qian <jinqian@android.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The seq_printf return value, because it's frequently misused,
will eventually be converted to void.

See: commit 1f33c41c ("seq_file: Rename seq_overflow() to
     seq_has_overflowed() and make public")
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: NRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NKevin Hilman <khilman@linaro.org>
Acked-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NRussell King <rmk+kernel@arm.linux.org.uk>
[ Ulf: Updated patch according to updates in driver core ]
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Occasionally, the system can't come back up after suspend/resume
due to problems of device suspending phase. This patch make
PM_TRACE infrastructure cover device suspending phase of
suspend/resume process, and the information in RTC can tell
developers which device suspending function make system hang.
Signed-off-by: NZhonghui Fu <zhonghui.fu@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Export pm_system_wakeup function to allow irq handlers to deal with system
wakeup.

This is needed for shared IRQ lines where one of the handler is registered
with IRQF_NO_SUSPEND, while the other ones want to configure it as a wakeup
source.

In this specific case, irq core does not handle the wakeup process and
leave the decision to each irq handler.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NKevin Hilman <khilman@linaro.org>
Acked-by: NPavel Machek <pavel@ucw.cz>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch reduces the kernel size by removing error messages that duplicate
the normal OOM message.

A simplified version of the semantic patch that finds this problem is as
follows: (http://coccinelle.lip6.fr)

@@
identifier f,print,l;
expression e;
constant char[] c;
@@

e = \(kzalloc\|kmalloc\|devm_kzalloc\|devm_kmalloc\)(...);
if (e == NULL) {
  <+...
-  print(...,c,...);
  ... when any
(
  goto l;
|
  return ...;
)
  ...+> }
Signed-off-by: NQuentin Lambert <lambert.quentin@gmail.com>
Acked-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Clients using the dev_pm_put_subsys_data() API isn't interested of a
return value. They care only of decreasing a reference to the device's
pm_subsys_data. So, let's convert the API to a void function, which
anyway seems like reasonable thing to do.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The commit "PM: Make dev_pm_get_subsys_data() always return 0 on success"
changed the return value from dev_pm_get_subsys_data(). Let's update the
comment in the function header to reflect this change as well.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add lockdep asserts for holding the RCU lock when calling
dev_pm_opp_get_freq() and dev_pm_opp_get_voltage() to aid in detecting
RCU misuses.

These are called often after dev_pm_opp_find_freq_ceil/exact() which
already asserts for RCU lock. However one could make an error by
releasing lock too early - just after dev_pm_opp_find_freq_ceil().
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add lockdep asserts for holding the dev->power.lock to non-static
functions which require this. They could be used outside of the file so
asserts may help in detecting locking misuse.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

kernel doc has gotten bit-rotted over time. Re-sync with Locking and
Return information. document all functions properly and ensure that
./scripts/kernel-doc -v  ./drivers/base/power/opp.c >/dev/null returns
no errors
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

All exported functions use dev_pm_* prefix and all static functions
are now standardized with _ prefix. This is better than having to deal
with multiple function naming styles within the same file.
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Allows user drivers such as devfreq to be modules.
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

A lot of callers are missing the fact that dev_pm_opp_get_opp_count
needs to be called under RCU lock. Given that RCU locks can safely be
nested, instead of providing *_locked() API, let's take RCU lock inside
dev_pm_opp_get_opp_count() and leave callers as is.
Signed-off-by: NDmitry Torokhov <dtor@chromium.org>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Not having OPP defined for a device is not a crime, we should not splat
warning in this case. Also, it seems that we are ready to accept invalid
dev (find_device_opp will return ERR_PTR(-EINVAL) then) so let's not
crash in dev_name() in such case.
Signed-off-by: NDmitry Torokhov <dtor@chromium.org>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Certain OPP APIs need to be called under RCU lock; let's add a few
rcu_lockdep_assert() calls to warn about potential misuse.
Signed-off-by: NDmitry Torokhov <dtor@chromium.org>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NAmit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>