kernel/linux.git/include/linux/pm_runtime.h, branch v6.19.11

PM: runtime: Make pm_runtime_barrier() return void

2025-12-04T19:38:13+00:00

No callers check the return code, and that's a good thing. Doing so would be racy and unhelpful. Drop the return code entirely, so we don't make anyone think about its complexities. Signed-off-by: Brian Norris Tested-by: Guenter Roeck Link: https://patch.msgid.link/20251202193129.1411419-2-briannorris@chromium.org Signed-off-by: Rafael J. Wysocki

PM: runtime: Wrapper macros for ACQUIRE()/ACQUIRE_ERR()

2025-11-14T20:24:54+00:00

Add wrapper macros for ACQUIRE()/ACQUIRE_ERR() and runtime PM usage counter guards introduced recently: pm_runtime_active_try, pm_runtime_active_auto_try, pm_runtime_active_try_enabled, and pm_runtime_active_auto_try_enabled. The new macros should be more straightforward to use. For example, they can be used for rewriting a piece of code like below: ACQUIRE(pm_runtime_active_try, pm)(dev); if ((ret = ACQUIRE_ERR(pm_runtime_active_try, &pm))) return ret; in the following way: PM_RUNTIME_ACQUIRE(dev, pm); if ((ret = PM_RUNTIME_ACQUIRE_ERR(&pm))) return ret; If the original code does not care about the specific error code returned when attepmting to resume the device: ACQUIRE(pm_runtime_active_try, pm)(dev); if (ACQUIRE_ERR(pm_runtime_active_try, &pm)) return -ENXIO; it may be changed like this: PM_RUNTIME_ACQUIRE(dev, pm); if (PM_RUNTIME_ACQUIRE_ERR(&pm)) return -ENXIO; Link: https://lore.kernel.org/linux-pm/5068916.31r3eYUQgx@rafael.j.wysocki/ Signed-off-by: Rafael J. Wysocki Reviewed-by: Dan Williams Reviewed-by: Dhruva Gole Reviewed-by: Jonathan Cameron Reviewed-by: Frank Li Link: https://patch.msgid.link/3400866.aeNJFYEL58@rafael.j.wysocki

PM: runtime: Fix conditional guard definitions

2025-10-22T09:38:11+00:00

Since pm_runtime_get_active() returns 0 on success, all of the DEFINE_GUARD_COND() macros in pm_runtime.h need the "_RET == 0" condition at the end of the argument list or they would not work correctly. Fixes: 9a0abc39450a ("PM: runtime: Add auto-cleanup macros for "resume and get" operations") Reported-by: kernel test robot Link: https://lore.kernel.org/linux-pm/202510191529.BCyjKlLQ-lkp@intel.com/ Signed-off-by: Rafael J. Wysocki Reviewed-by: Jonathan Cameron Reviewed-by: Dan Williams Tested-by: Farhan Ali Link: https://patch.msgid.link/5943878.DvuYhMxLoT@rafael.j.wysocki

PM: runtime: Introduce one more usage counter guard

2025-10-03T19:09:54+00:00

Follow previous commit 9a0abc39450a ("PM: runtime: Add auto-cleanup macros for "resume and get" operations") and define a runtime PM usage counter guard in which pm_runtime_get_noresume() and pm_runtime_put_noidle() will be used for incrementing and decrementing it, respectively. Signed-off-by: Rafael J. Wysocki Reviewed-by: Jonathan Cameron

PM: runtime: Drop DEFINE_FREE() for pm_runtime_put()

2025-09-29T15:01:54+00:00

The DEFINE_FREE() for pm_runtime_put has been superseded by recently introduced runtime PM auto-cleanup macros and its only user has been converted to using one of the new macros, so drop it. Signed-off-by: Rafael J. Wysocki Reviewed-by: Dhruva Gole Reviewed-by: Takashi Iwai Reviewed-by: Jonathan Cameron

PM: runtime: Add auto-cleanup macros for "resume and get" operations

2025-09-29T15:00:21+00:00

It is generally useful to be able to automatically drop a device's runtime PM usage counter incremented by runtime PM operations that resume a device and bump up its usage counter [1]. To that end, add guard definition macros allowing pm_runtime_put() and pm_runtime_put_autosuspend() to be used for the auto-cleanup in those cases. Simply put, a piece of code like below: pm_runtime_get_sync(dev); ..... pm_runtime_put(dev); return 0; can be transformed with guard() like: guard(pm_runtime_active)(dev); ..... return 0; (see the pm_runtime_put() call is gone). However, it is better to do proper error handling in the majority of cases, so doing something like this instead of the above is recommended: ACQUIRE(pm_runtime_active_try, pm)(dev); if (ACQUIRE_ERR(pm_runtime_active_try, &pm)) return -ENXIO; ..... return 0; In all of the cases in which runtime PM is known to be enabled for the given device or the device can be regarded as operational (and so it can be accessed) with runtime PM disabled, a piece of code like: ret = pm_runtime_resume_and_get(dev); if (ret < 0) return ret; ..... pm_runtime_put(dev); return 0; can be changed as follows: ACQUIRE(pm_runtime_active_try, pm)(dev); ret = ACQUIRE_ERR(pm_runtime_active_try, &pm); if (ret < 0) return ret; ..... return 0; (again, see the pm_runtime_put() call is gone). Still, if the device cannot be accessed unless runtime PM has been enabled for it, the pm_runtime_active_try_enabled guard variant needs to be used, that is (in the context of the example above): ACQUIRE(pm_runtime_active_try_enabled, pm)(dev); ret = ACQUIRE_ERR(pm_runtime_active_try_enabled, &pm); if (ret < 0) return ret; ..... return 0; When the original code calls pm_runtime_put_autosuspend(), use one of the "auto" guard variants, pm_runtime_active_auto/_try/_enabled, so for example, a piece of code like: ret = pm_runtime_resume_and_get(dev); if (ret < 0) return ret; ..... pm_runtime_put_autosuspend(dev); return 0; will become: ACQUIRE(pm_runtime_active_auto_try_enabled, pm)(dev); ret = ACQUIRE_ERR(pm_runtime_active_auto_try_enabled, &pm); if (ret < 0) return ret; ..... return 0; Note that the cases in which the return value of pm_runtime_get_sync() is checked can also be handled with the help of the new guard macros. For example, a piece of code like: ret = pm_runtime_get_sync(dev); if (ret < 0) { pm_runtime_put(dev); return ret; } ..... pm_runtime_put(dev); return 0; can be rewritten as: ACQUIRE(pm_runtime_active_auto_try_enabled, pm)(dev); ret = ACQUIRE_ERR(pm_runtime_active_auto_try_enabled, &pm); if (ret < 0) return ret; ..... return 0; or pm_runtime_get_active_try can be used if transparent handling of disabled runtime PM is desirable. Link: https://lore.kernel.org/linux-pm/878qimv24u.wl-tiwai@suse.de/ [1] Link: https://lore.kernel.org/linux-pm/20250926150613.000073a4@huawei.com/ Signed-off-by: Rafael J. Wysocki Acked-by: Dan Williams Reviewed-by: Takashi Iwai Link: https://patch.msgid.link/2238241.irdbgypaU6@rafael.j.wysocki [ rjw: Fixed leftovers from the previous version in the changelog ] Reviewed-by: Jonathan Cameron Reviewed-by: Dhruva Gole Signed-off-by: Rafael J. Wysocki

PM: runtime: Update kerneldoc return codes

2025-09-27T11:41:47+00:00

APIs based on __pm_runtime_idle() (pm_runtime_idle(), pm_request_idle()) do not return 1 when already suspended. They return -EAGAIN. This is already covered in the docs, so the entry for "1" is redundant and conflicting. (pm_runtime_put() and pm_runtime_put_sync() were previously incorrect, but that's fixed in "PM: runtime: pm_runtime_put{,_sync}() returns 1 when already suspended", to ensure consistency with APIs like pm_runtime_put_autosuspend().) RPM_GET_PUT APIs based on __pm_runtime_suspend() do return 1 when already suspended, but the language is a little unclear -- it's not really an "error", so it seems better to list as a clarification before the 0/success case. Additionally, they only actually return 1 when the refcount makes it to 0; if the usage counter is still non-zero, we return 0. pm_runtime_put(), etc., also don't appear at first like they can ever see "-EAGAIN: Runtime PM usage_count non-zero", because in non-racy conditions, pm_runtime_put() would drop its reference count, see it's non-zero, and return early (in __pm_runtime_idle()). However, it's possible to race with another actor that increments the usage_count afterward, since rpm_idle() is protected by a separate lock; in such a case, we may see -EAGAIN. Because this case is only seen in the presence of concurrent actors, it makes sense to clarify that this is when "usage_count **became** non-zero", by way of some racing actor. Lastly, pm_runtime_put_sync_suspend() duplicated some -EAGAIN language. Fix that. Fixes: 271ff96d6066 ("PM: runtime: Document return values of suspend-related API functions") Link: https://lore.kernel.org/linux-pm/aJ5pkEJuixTaybV4@google.com/ Signed-off-by: Brian Norris Reviewed-by: Sakari Ailus Cc: 6.17+ # 6.17+ Signed-off-by: Rafael J. Wysocki

Merge branches 'pm-runtime' and 'pm-powercap'

2025-07-22T16:01:15+00:00

Merge runtime PM updates and power capping updates for 6.17-rc1: - Document return values of suspend-related API functions in the runtime PM framework (Sakari Ailus) - Mark last busy stamp in multiple autosuspend-related functions in the runtime PM framework and update its documentation (Sakari Ailus) - Take active children into account in pm_runtime_get_if_in_use() for consistency (Rafael Wysocki) - Fix NULL pointer dereference in get_pd_power_uw() in the dtpm_cpu power capping driver (Sivan Zohar-Kotzer) - Add support for the Bartlett Lake platform to the Intel RAPL power capping driver (Qiao Wei) - Add PL4 support for Panther Lake to the intel_rapl_msr power capping driver (Zhang Rui) * pm-runtime: PM: runtime: Take active children into account in pm_runtime_get_if_in_use() Documentation: PM: *_autosuspend() functions update last busy time PM: runtime: Mark last busy stamp in pm_request_autosuspend() PM: runtime: Mark last busy stamp in pm_runtime_autosuspend() PM: runtime: Mark last busy stamp in pm_runtime_put_sync_autosuspend() PM: runtime: Mark last busy stamp in pm_runtime_put_autosuspend() PM: runtime: Document return values of suspend-related API functions * pm-powercap: powercap: dtpm_cpu: Fix NULL pointer dereference in get_pd_power_uw() powercap: intel_rapl: Add support for Bartlett Lake platform powercap: intel_rapl_msr: Add PL4 support for Panther Lake

PM: Move two sleep-related functions under CONFIG_PM_SLEEP

2025-07-03T15:10:40+00:00

Since pm_runtime_force_resume() and pm_runtime_need_not_resume() are only needed for handling system-wide PM transitions, there is no reason to compile them in if CONFIG_PM_SLEEP is unset. Accordingly, move them under CONFIG_PM_SLEEP and make the static inline stub for pm_runtime_force_resume() return an error to indicate that it should not be used outside CONFIG_PM_SLEEP. Putting pm_runtime_force_resume() also allows subsequent changes to be more straightforward because this function is going to access a device PM flag that is only defined when CONFIG_PM_SLEEP is set. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Link: https://patch.msgid.link/3384523.aeNJFYEL58@rjwysocki.net

PM: runtime: Mark last busy stamp in pm_request_autosuspend()

2025-06-18T19:41:08+00:00

Set device's last busy timestamp to current time in pm_request_autosuspend(). Signed-off-by: Sakari Ailus Reviewed-by: Laurent Pinchart Link: https://patch.msgid.link/20250616061212.2286741-6-sakari.ailus@linux.intel.com Signed-off-by: Rafael J. Wysocki