linux-stable.git/drivers/base/power/runtime.c, branch v5.10.239

PM: runtime: fix denying of auto suspend in pm_suspend_timer_fn()

2025-06-27T10:04:15+00:00

[ Upstream commit 40d3b40dce375d6f1c1dbf08d79eed3aed6c691d ]

pm_runtime_put_autosuspend() schedules a hrtimer to expire
at "dev->power.timer_expires". If the hrtimer's callback,
pm_suspend_timer_fn(), observes that the current time equals
"dev->power.timer_expires", it unexpectedly bails out instead of
proceeding with runtime suspend.

pm_suspend_timer_fn():

 if (expires > 0 && expires < ktime_get_mono_fast_ns()) {
 	dev->power.timer_expires = 0;
 	rpm_suspend(..)
 }

Additionally, as ->timer_expires is not cleared, all the future auto
suspend requests will not schedule hrtimer to perform auto suspend.

rpm_suspend():

 if ((rpmflags & RPM_AUTO) &&...) {
 	if (!(dev->power.timer_expires && ...) { <-- this will fail.
 		hrtimer_start_range_ns(&dev->power.suspend_timer,...);
 	}
 }

Fix this by as well checking if current time reaches the set expiration.

Co-developed-by: Patrick Daly 
Signed-off-by: Patrick Daly 
Signed-off-by: Charan Teja Kalla 
Link: https://patch.msgid.link/20250515064125.1211561-1-quic_charante@quicinc.com
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

PM: sleep: Adjust check before setting power.must_resume

2025-04-10T12:30:55+00:00

[ Upstream commit eeb87d17aceab7803a5a5bcb6cf2817b745157cf ]

The check before setting power.must_resume in device_suspend_noirq()
does not take power.child_count into account, but it should do that, so
use pm_runtime_need_not_resume() in it for this purpose and adjust the
comment next to it accordingly.

Fixes: 107d47b2b95e ("PM: sleep: core: Simplify the SMART_SUSPEND flag handling")
Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Ulf Hansson 
Link: https://patch.msgid.link/3353728.44csPzL39Z@rjwysocki.net
Signed-off-by: Sasha Levin

PM: runtime: Have devm_pm_runtime_enable() handle pm_runtime_dont_use_autosuspend()

2024-02-23T07:42:32+00:00

[ Upstream commit b4060db9251f919506e4d672737c6b8ab9a84701 ]

The PM Runtime docs say:

  Drivers in ->remove() callback should undo the runtime PM changes done
  in ->probe(). Usually this means calling pm_runtime_disable(),
  pm_runtime_dont_use_autosuspend() etc.

>From grepping code, it's clear that many people aren't aware of the
need to call pm_runtime_dont_use_autosuspend().

When brainstorming solutions, one idea that came up was to leverage
the new-ish devm_pm_runtime_enable() function. The idea here is that:

 * When the devm action is called we know that the driver is being
   removed. It's the perfect time to undo the use_autosuspend.

 * The code of pm_runtime_dont_use_autosuspend() already handles the
   case of being called when autosuspend wasn't enabled.

Suggested-by: Laurent Pinchart 
Signed-off-by: Douglas Anderson 
Reviewed-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Stable-dep-of: 3d07a411b4fa ("drm/msm/dsi: Use pm_runtime_resume_and_get to prevent refcnt leaks")
Signed-off-by: Amit Pundir 
Signed-off-by: Greg Kroah-Hartman

PM: runtime: add devm_pm_runtime_enable helper

2024-02-23T07:42:32+00:00

[ Upstream commit b3636a3a2c51715736d3ec45f635ed03191962ce ]

A typical code pattern for pm_runtime_enable() call is to call it in the
_probe function and to call pm_runtime_disable() both from _probe error
path and from _remove function. For some drivers the whole remove
function would consist of the call to pm_remove_disable().

Add helper function to replace this bolierplate piece of code. Calling
devm_pm_runtime_enable() removes the need for calling
pm_runtime_disable() both in the probe()'s error path and in the
remove() function.

Signed-off-by: Dmitry Baryshkov 
Link: https://lore.kernel.org/r/20210731195034.979084-2-dmitry.baryshkov@linaro.org
Acked-by: Rafael J. Wysocki 
Signed-off-by: Stephen Boyd 
Stable-dep-of: 3d07a411b4fa ("drm/msm/dsi: Use pm_runtime_resume_and_get to prevent refcnt leaks")
Signed-off-by: Amit Pundir 
Signed-off-by: Greg Kroah-Hartman

PM / wakeirq: support enabling wake-up irq after runtime_suspend called

2023-08-11T09:57:55+00:00

[ Upstream commit 259714100d98b50bf04d36a21bf50ca8b829fc11 ]

When the dedicated wake IRQ is level trigger, and it uses the
device's low-power status as the wakeup source, that means if the
device is not in low-power state, the wake IRQ will be triggered
if enabled; For this case, need enable the wake IRQ after running
the device's ->runtime_suspend() which make it enter low-power state.

e.g.
Assume the wake IRQ is a low level trigger type, and the wakeup
signal comes from the low-power status of the device.
The wakeup signal is low level at running time (0), and becomes
high level when the device enters low-power state (runtime_suspend
(1) is called), a wakeup event at (2) make the device exit low-power
state, then the wakeup signal also becomes low level.

                ------------------
               |           ^     ^|
----------------           |     | --------------
 |<---(0)--->|<--(1)--|   (3)   (2)    (4)

if enable the wake IRQ before running runtime_suspend during (0),
a wake IRQ will arise, it causes resume immediately;
it works if enable wake IRQ ( e.g. at (3) or (4)) after running
->runtime_suspend().

This patch introduces a new status WAKE_IRQ_DEDICATED_REVERSE to
optionally support enabling wake IRQ after running ->runtime_suspend().

Suggested-by: Rafael J. Wysocki 
Signed-off-by: Chunfeng Yun 
Signed-off-by: Rafael J. Wysocki 
Stable-dep-of: 8527beb12087 ("PM: sleep: wakeirq: fix wake irq arming")
Signed-off-by: Sasha Levin

PM: runtime: Do not call __rpm_callback() from rpm_idle()

2023-01-14T09:15:21+00:00

[ Upstream commit bc80c2e438dcbfcf748452ec0f7ad5b79ff3ad88 ]

Calling __rpm_callback() from rpm_idle() after adding device links
support to the former is a clear mistake.

Not only it causes rpm_idle() to carry out unnecessary actions, but it
is also against the assumption regarding the stability of PM-runtime
status across __rpm_callback() invocations, because rpm_suspend() and
rpm_resume() may run in parallel with __rpm_callback() when it is called
by rpm_idle() and the device's PM-runtime status can be updated by any
of them.

Fixes: 21d5c57b3726 ("PM / runtime: Use device links")
Link: https://lore.kernel.org/linux-pm/36aed941-a73e-d937-2721-4f0decd61ce0@quicinc.com
Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Adrian Hunter 
Signed-off-by: Sasha Levin

PM: runtime: Improve path in rpm_idle() when no callback

2023-01-14T09:15:21+00:00

[ Upstream commit 5a2bd1b1c64e1ac5627db3767ac465f18606315c ]

When pm_runtime_no_callbacks() has been called for a struct device to set
the dev->power.no_callbacks flag for it, it enables rpm_idle() to take a
slightly quicker path by assuming that a ->runtime_idle() callback would
have returned 0 to indicate success.

A device that does not have the dev->power.no_callbacks flag set for it,
may still be missing a corresponding ->runtime_idle() callback, in which
case the slower path in rpm_idle() is taken. Let's improve the behaviour
for this case, by aligning code to the quicker path.

Signed-off-by: Ulf Hansson 
Acked-by: Alan Stern 
Signed-off-by: Rafael J. Wysocki 
Stable-dep-of: bc80c2e438dc ("PM: runtime: Do not call __rpm_callback() from rpm_idle()")
Signed-off-by: Sasha Levin

PM: runtime: Redefine pm_runtime_release_supplier()

2022-07-12T14:32:18+00:00

commit 07358194badf73e267289b40b761f5dc56928eab upstream.

Instead of passing an extra bool argument to pm_runtime_release_supplier(),
make its callers take care of triggering a runtime-suspend of the
supplier device as needed.

No expected functional impact.

Suggested-by: Greg Kroah-Hartman 
Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Greg Kroah-Hartman 
Cc: 5.1+  # 5.1+
Signed-off-by: Greg Kroah-Hartman

PM: runtime: Add safety net to supplier device release

2022-01-27T09:54:17+00:00

[ Upstream commit d1579e61192e0e686faa4208500ef4c3b529b16c ]

Because refcount_dec_not_one() returns true if the target refcount
becomes saturated, it is generally unsafe to use its return value as
a loop termination condition, but that is what happens when a device
link's supplier device is released during runtime PM suspend
operations and on device link removal.

To address this, introduce pm_runtime_release_supplier() to be used
in the above cases which will check the supplier device's runtime
PM usage counter in addition to the refcount_dec_not_one() return
value, so the loop can be terminated in case the rpm_active refcount
value becomes invalid, and update the code in question to use it as
appropriate.

This change is not expected to have any visible functional impact.

Reported-by: Peter Zijlstra 
Signed-off-by: Rafael J. Wysocki 
Acked-by: Greg Kroah-Hartman 
Acked-by: Peter Zijlstra (Intel) 
Signed-off-by: Sasha Levin

PM: runtime: Fix unpaired parent child_count for force_resume

2021-05-19T08:12:51+00:00

commit c745253e2a691a40c66790defe85c104a887e14a upstream.

As pm_runtime_need_not_resume() relies also on usage_count, it can return
a different value in pm_runtime_force_suspend() compared to when called in
pm_runtime_force_resume(). Different return values can happen if anything
calls PM runtime functions in between, and causes the parent child_count
to increase on every resume.

So far I've seen the issue only for omapdrm that does complicated things
with PM runtime calls during system suspend for legacy reasons:

omap_atomic_commit_tail() for omapdrm.0
 dispc_runtime_get()
  wakes up 58000000.dss as it's the dispc parent
   dispc_runtime_resume()
    rpm_resume() increases parent child_count
 dispc_runtime_put() won't idle, PM runtime suspend blocked
pm_runtime_force_suspend() for 58000000.dss, !pm_runtime_need_not_resume()
 __update_runtime_status()
system suspended
pm_runtime_force_resume() for 58000000.dss, pm_runtime_need_not_resume()
 pm_runtime_enable() only called because of pm_runtime_need_not_resume()
omap_atomic_commit_tail() for omapdrm.0
 dispc_runtime_get()
  wakes up 58000000.dss as it's the dispc parent
   dispc_runtime_resume()
    rpm_resume() increases parent child_count
 dispc_runtime_put() won't idle, PM runtime suspend blocked
...
rpm_suspend for 58000000.dss but parent child_count is now unbalanced

Let's fix the issue by adding a flag for needs_force_resume and use it in
pm_runtime_force_resume() instead of pm_runtime_need_not_resume().

Additionally omapdrm system suspend could be simplified later on to avoid
lots of unnecessary PM runtime calls and the complexity it adds. The
driver can just use internal functions that are shared between the PM
runtime and system suspend related functions.

Fixes: 4918e1f87c5f ("PM / runtime: Rework pm_runtime_force_suspend/resume()")
Signed-off-by: Tony Lindgren 
Reviewed-by: Ulf Hansson 
Tested-by: Tomi Valkeinen 
Cc: 4.16+  # 4.16+
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman