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path: root/drivers/base/power/runtime.c
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2025-05-16PM: runtime: fix denying of auto suspend in pm_suspend_timer_fn()Charan Teja Kalla
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 <quic_pdaly@quicinc.com> Signed-off-by: Patrick Daly <quic_pdaly@quicinc.com> Signed-off-by: Charan Teja Kalla <quic_charante@quicinc.com> Link: https://patch.msgid.link/20250515064125.1211561-1-quic_charante@quicinc.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-04-29PM: runtime: Add new devm functionsBence Csókás
Add `devm_pm_runtime_set_active_enabled()` and `devm_pm_runtime_get_noresume()` for simplifying common cases in drivers. Signed-off-by: Bence Csókás <csokas.bence@prolan.hu> Link: https://patch.msgid.link/20250327195928.680771-3-csokas.bence@prolan.hu Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-03-25Merge tag 'pm-6.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These are dominated by cpufreq updates which in turn are dominated by updates related to boost support in the core and drivers and amd-pstate driver optimizations. Apart from the above, there are some cpuidle updates including a rework of the most recent idle intervals handling in the venerable menu governor that leads to significant improvements in some performance benchmarks, as the governor is now more likely to predict a shorter idle duration in some cases, and there are updates of the core device power management code, mostly related to system suspend and resume, that should help to avoid potential issues arising when the drivers of devices depending on one another want to use different optimizations. There is also a usual collection of assorted fixes and cleanups, including removal of some unused code. Specifics: - Manage sysfs attributes and boost frequencies efficiently from cpufreq core to reduce boilerplate code in drivers (Viresh Kumar) - Minor cleanups to cpufreq drivers (Aaron Kling, Benjamin Schneider, Dhananjay Ugwekar, Imran Shaik, zuoqian) - Migrate some cpufreq drivers to using for_each_present_cpu() (Jacky Bai) - cpufreq-qcom-hw DT binding fixes (Krzysztof Kozlowski) - Use str_enable_disable() helper in cpufreq_online() (Lifeng Zheng) - Optimize the amd-pstate driver to avoid cases where call paths end up calling the same writes multiple times and needlessly caching variables through code reorganization, locking overhaul and tracing adjustments (Mario Limonciello, Dhananjay Ugwekar) - Make it possible to avoid enabling capacity-aware scheduling (CAS) in the intel_pstate driver and relocate a check for out-of-band (OOB) platform handling in it to make it detect OOB before checking HWP availability (Rafael Wysocki) - Fix dbs_update() to avoid inadvertent conversions of negative integer values to unsigned int which causes CPU frequency selection to be inaccurate in some cases when the "conservative" cpufreq governor is in use (Jie Zhan) - Update the handling of the most recent idle intervals in the menu cpuidle governor to prevent useful information from being discarded by it in some cases and improve the prediction accuracy (Rafael Wysocki) - Make it possible to tell the intel_idle driver to ignore its built-in table of idle states for the given processor, clean up the handling of auto-demotion disabling on Baytrail and Cherrytrail chips in it, and update its MAINTAINERS entry (David Arcari, Artem Bityutskiy, Rafael Wysocki) - Make some cpuidle drivers use for_each_present_cpu() instead of for_each_possible_cpu() during initialization to avoid issues occurring when nosmp or maxcpus=0 are used (Jacky Bai) - Clean up the Energy Model handling code somewhat (Rafael Wysocki) - Use kfree_rcu() to simplify the handling of runtime Energy Model updates (Li RongQing) - Add an entry for the Energy Model framework to MAINTAINERS as properly maintained (Lukasz Luba) - Address RCU-related sparse warnings in the Energy Model code (Rafael Wysocki) - Remove ENERGY_MODEL dependency on SMP and allow it to be selected when DEVFREQ is set without CPUFREQ so it can be used on a wider range of systems (Jeson Gao) - Unify error handling during runtime suspend and runtime resume in the core to help drivers to implement more consistent runtime PM error handling (Rafael Wysocki) - Drop a redundant check from pm_runtime_force_resume() and rearrange documentation related to __pm_runtime_disable() (Rafael Wysocki) - Rework the handling of the "smart suspend" driver flag in the PM core to avoid issues hat may occur when drivers using it depend on some other drivers and clean up the related PM core code (Rafael Wysocki, Colin Ian King) - Fix the handling of devices with the power.direct_complete flag set if device_suspend() returns an error for at least one device to avoid situations in which some of them may not be resumed (Rafael Wysocki) - Use mutex_trylock() in hibernate_compressor_param_set() to avoid a possible deadlock that may occur if the "compressor" hibernation module parameter is accessed during the registration of a new ieee80211 device (Lizhi Xu) - Suppress sleeping parent warning in device_pm_add() in the case when new children are added under a device with the power.direct_complete set after it has been processed by device_resume() (Xu Yang) - Remove needless return in three void functions related to system wakeup (Zijun Hu) - Replace deprecated kmap_atomic() with kmap_local_page() in the hibernation core code (David Reaver) - Remove unused helper functions related to system sleep (David Alan Gilbert) - Clean up s2idle_enter() so it does not lock and unlock CPU offline in vain and update comments in it (Ulf Hansson) - Clean up broken white space in dpm_wait_for_children() (Geert Uytterhoeven) - Update the cpupower utility to fix lib version-ing in it and memory leaks in error legs, remove hard-coded values, and implement CPU physical core querying (Thomas Renninger, John B. Wyatt IV, Shuah Khan, Yiwei Lin, Zhongqiu Han)" * tag 'pm-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (139 commits) PM: sleep: Fix bit masking operation dt-bindings: cpufreq: cpufreq-qcom-hw: Narrow properties on SDX75, SA8775p and SM8650 dt-bindings: cpufreq: cpufreq-qcom-hw: Drop redundant minItems:1 dt-bindings: cpufreq: cpufreq-qcom-hw: Add missing constraint for interrupt-names dt-bindings: cpufreq: cpufreq-qcom-hw: Add QCS8300 compatible cpufreq: Init cpufreq only for present CPUs PM: sleep: Fix handling devices with direct_complete set on errors cpuidle: Init cpuidle only for present CPUs PM: clk: Remove unused pm_clk_remove() PM: sleep: core: Fix indentation in dpm_wait_for_children() PM: s2idle: Extend comment in s2idle_enter() PM: s2idle: Drop redundant locks when entering s2idle PM: sleep: Remove unused pm_generic_ wrappers cpufreq: tegra186: Share policy per cluster cpupower: Make lib versioning scheme more obvious and fix version link PM: EM: Rework the depends on for CONFIG_ENERGY_MODEL PM: EM: Address RCU-related sparse warnings cpupower: Implement CPU physical core querying pm: cpupower: remove hard-coded topology depth values pm: cpupower: Fix cmd_monitor() error legs to free cpu_topology ...
2025-03-24Merge branch 'pm-sleep'Rafael J. Wysocki
Merge updates related to system sleep for 6.15-rc1 including fixes, cleanups and a rework of the "smart suspend" driver flag handling to avoid issues that may occur when drivers using it depend on some other drivers: - Rework the handling of the "smart suspend" driver flag in the PM core to avoid issues hat may occur when drivers using it depend on some other drivers and clean up the related PM core code (Rafael Wysocki, Colin Ian King). - Fix the handling of devices with the power.direct_complete flag set if device_suspend() returns an error for at least one device to avoid situations in which some of them may not be resumed (Rafael Wysocki). - Use mutex_trylock() in hibernate_compressor_param_set() to avoid a possible deadlock that may occur if the "compressor" hibernation module parameter is accessed during the registration of a new ieee80211 device (Lizhi Xu). - Suppress sleeping parent warning in device_pm_add() in the case when new children are added under a device with the power.direct_complete set after it has been processed by device_resume() (Xu Yang). - Remove needless return in three void functions related to system wakeup (Zijun Hu). - Replace deprecated kmap_atomic() with kmap_local_page() in the hibernation core code (David Reaver). - Remove unused helper functions related to system sleep (David Alan Gilbert). - Clean up s2idle_enter() so it does not lock and unlock CPU offline in vain and update comments in it (Ulf Hansson). - Clean up broken white space in dpm_wait_for_children() (Geert Uytterhoeven). * pm-sleep: PM: sleep: Fix bit masking operation PM: sleep: Fix handling devices with direct_complete set on errors PM: sleep: core: Fix indentation in dpm_wait_for_children() PM: s2idle: Extend comment in s2idle_enter() PM: s2idle: Drop redundant locks when entering s2idle PM: sleep: Remove unused pm_generic_ wrappers PM: sleep: Rearrange dpm_async_fn() and async state clearing PM: sleep: Rename power.async_in_progress to power.work_in_progress PM: core: Tweak pm_runtime_block_if_disabled() return value PM: runtime: Convert pm_runtime_blocked() to static inline PM: sleep: Update power.smart_suspend under PM spinlock PM: sleep: Adjust check before setting power.must_resume PM: wakeup: Remove needless return in three void APIs PM: sleep: Suppress sleeping parent warning in special case PM: hibernate: Avoid deadlock in hibernate_compressor_param_set() PM: sleep: Avoid unnecessary checks in device_prepare_smart_suspend() PM: sleep: Use DPM_FLAG_SMART_SUSPEND conditionally PM: runtime: Introduce pm_runtime_blocked() PM: Block enabling of runtime PM during system suspend PM: hibernate: Replace deprecated kmap_atomic() with kmap_local_page()
2025-03-03PM: runtime: Unify error handling during suspend and resumeRafael J. Wysocki
There is a confusing difference in error handling between rpm_suspend() and rpm_resume() related to the special way in which -EAGAIN and -EBUSY error values are treated by the former. Also, converting -EACCES coming from the callback to I/O error, which it quite likely is not, may confuse runtime PM users. To address the above, modify rpm_callback() to convert -EACCES coming from the driver to -EAGAIN and to set power.runtime_error only if the return value is not -EAGAIN or -EBUSY. This will cause the error handling in rpm_resume() and rpm_suspend() to work consistently, so drop the no longer needed -EAGAIN or -EBUSY special case from the latter and make it retry autosuspend if power.runtime_error is unset. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/12620037.O9o76ZdvQC@rjwysocki.net
2025-03-03PM: core: Tweak pm_runtime_block_if_disabled() return valueRafael J. Wysocki
Modify pm_runtime_block_if_disabled() to return true when runtime PM is disabled for the device, regardless of the power.last_status value. This effectively prevents "smart suspend" from being enabled for devices with runtime PM disabled in device_prepare(), even transiently, so update the related comment in that function accordingly. If a device has runtime PM disabled in device_prepare(), it is not actually known whether or not runtime PM will be enabled for that device going forward, so it is more appropriate to postpone the "smart suspend" optimization for the device in the given system suspend-resume cycle than to enable it and get confused going forward. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/13718674.uLZWGnKmhe@rjwysocki.net
2025-03-03PM: runtime: Convert pm_runtime_blocked() to static inlineRafael J. Wysocki
The comment in pm_runtime_blocked() is acutally wrong: power.last_status is not a bit field. Its data type is an enum and so one can reasonably assume that partial updates of it will not be observed. Accordingly, pm_runtime_blocked() can be converted to a static inline function and the related locking overhead can be eliminated, so long as it is only used in system suspend/resume code paths because power.last_status is not expected to be updated concurrently while that code is running. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/1923449.tdWV9SEqCh@rjwysocki.net
2025-03-03PM: sleep: Adjust check before setting power.must_resumeRafael J. Wysocki
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 <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/3353728.44csPzL39Z@rjwysocki.net
2025-03-03PM: runtime: Drop status check from pm_runtime_force_resume()Rafael J. Wysocki
Since pm_runtime_force_resume() requires pm_runtime_force_suspend() to be called before it on the same device, the runtime PM status of the device is RPM_SUSPENDED when it is called unless the device's runtime PM status is changed somewhere else in the meantime. However, even if that happens, the power.needs_force_resume check is still required to pass and that flag is only set by pm_runtime_force_suspend() once and it is cleared at the end of pm_runtime_force_resume(), so it cannot be taken into account twice in a row. According to the above, the pm_runtime_status_suspended(dev) check in pm_runtime_force_resume() is redundant, so drop it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/2309120.iZASKD2KPV@rjwysocki.net
2025-03-03PM: sleep: Avoid unnecessary checks in device_prepare_smart_suspend()Rafael J. Wysocki
Add an optimization (on top of previous changes) to avoid calling pm_runtime_blocked(), which involves acquiring the device's PM spinlock, for devices with no PM callbacks and runtime PM "blocked". Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/2978873.e9J7NaK4W3@rjwysocki.net
2025-02-18PM: runtime: Introduce pm_runtime_blocked()Rafael J. Wysocki
Introduce a new helper function called pm_runtime_blocked() for checking the power.last_status value indicating whether or not enabling runtime PM for the given device has been blocked (which happens in the "prepare" phase of system-wide suspend if runtime PM is disabled for the given device at that point). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/4632087.LvFx2qVVIh@rjwysocki.net
2025-02-18PM: Block enabling of runtime PM during system suspendRafael J. Wysocki
If device_prepare() runs on a device that has never had runtime PM enabled so far, it may reasonably assume that runtime PM will not be enabled for that device during the system suspend-resume cycle currently in progress, but this has never been guaranteed. To verify this assumption, make device_prepare() arrange for triggering a device warning accompanied by a call trace dump if runtime PM is enabled for such a device after it has returned. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/6131109.lOV4Wx5bFT@rjwysocki.net
2025-02-18PM: Rearrange documentation related to __pm_runtime_disable()Rafael J. Wysocki
There are only two callers of __pm_runtime_disable(), one of which is device_suspend_late() and the other is pm_runtime_disable() that has its own kerneldoc comment and there are no plans to add any more of them. Since they use different values of the __pm_runtime_disable() second parameter, the actual code behavior is different in each case, but it is all documented in the __pm_runtime_disable() kerneldoc comment which is not particularly straightforward. For this reason, move the information from the __pm_runtime_disable() kerneldoc comment to the pm_runtime_disable() one and into a separate comment in device_suspend_late() and remove the __pm_runtime_disable() kerneldoc comment altogether. No functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/12617588.O9o76ZdvQC@rjwysocki.net
2025-02-18PM: runtime: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/all/8d1ce108b043896733ce08d3deea6e84941d499b.1738746821.git.namcao@linutronix.de
2024-02-22PM: runtime: add tracepoint for runtime_status changesVilas Bhat
Existing runtime PM ftrace events (`rpm_suspend`, `rpm_resume`, `rpm_return_int`) offer limited visibility into the exact timing of device runtime power state transitions, particularly when asynchronous operations are involved. When the `rpm_suspend` or `rpm_resume` functions are invoked with the `RPM_ASYNC` flag, a return value of 0 i.e., success merely indicates that the device power state request has been queued, not that the device has yet transitioned. A new ftrace event, `rpm_status`, is introduced. This event directly logs the `power.runtime_status` value of a device whenever it changes providing granular tracking of runtime power state transitions regardless of synchronous or asynchronous `rpm_suspend` / `rpm_resume` usage. Signed-off-by: Vilas Bhat <vilasbhat@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-02-12PM: runtime: Simplify pm_runtime_get_if_active() usageSakari Ailus
There are two ways to opportunistically increment a device's runtime PM usage count, calling either pm_runtime_get_if_active() or pm_runtime_get_if_in_use(). The former has an argument to tell whether to ignore the usage count or not, and the latter simply calls the former with ign_usage_count set to false. The other users that want to ignore the usage_count will have to explicitly set that argument to true which is a bit cumbersome. To make this function more practical to use, remove the ign_usage_count argument from the function. The main implementation is in a static function called pm_runtime_get_conditional() and implementations of pm_runtime_get_if_active() and pm_runtime_get_if_in_use() are moved to runtime.c. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Alex Elder <elder@linaro.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Takashi Iwai <tiwai@suse.de> # sound/ Reviewed-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com> # drivers/accel/ivpu/ Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com> # drivers/gpu/drm/i915/ Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> # drivers/pci/ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-12-20PM: fix missing rculist.h dependencyKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-02-21Merge tag 'pm-6.3-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These add EPP support to the AMD P-state cpufreq driver, add support for new platforms to the Intel RAPL power capping driver, intel_idle and the Qualcomm cpufreq driver, enable thermal cooling for Tegra194, drop the custom cpufreq driver for loongson1 that is not necessary any more (and the corresponding cpufreq platform device), fix assorted issues and clean up code. Specifics: - Add EPP support to the AMD P-state cpufreq driver (Perry Yuan, Wyes Karny, Arnd Bergmann, Bagas Sanjaya) - Drop the custom cpufreq driver for loongson1 that is not necessary any more and the corresponding cpufreq platform device (Keguang Zhang) - Remove "select SRCU" from system sleep, cpufreq and OPP Kconfig entries (Paul E. McKenney) - Enable thermal cooling for Tegra194 (Yi-Wei Wang) - Register module device table and add missing compatibles for cpufreq-qcom-hw (Nícolas F. R. A. Prado, Abel Vesa and Luca Weiss) - Various dt binding updates for qcom-cpufreq-nvmem and opp-v2-kryo-cpu (Christian Marangi) - Make kobj_type structure in the cpufreq core constant (Thomas Weißschuh) - Make cpufreq_unregister_driver() return void (Uwe Kleine-König) - Make the TEO cpuidle governor check CPU utilization in order to refine idle state selection (Kajetan Puchalski) - Make Kconfig select the haltpoll cpuidle governor when the haltpoll cpuidle driver is selected and replace a default_idle() call in that driver with arch_cpu_idle() to allow MWAIT to be used (Li RongQing) - Add Emerald Rapids Xeon support to the intel_idle driver (Artem Bityutskiy) - Add ARCH_SUSPEND_POSSIBLE dependencies for ARMv4 cpuidle drivers to avoid randconfig build failures (Arnd Bergmann) - Make kobj_type structures used in the cpuidle sysfs interface constant (Thomas Weißschuh) - Make the cpuidle driver registration code update microsecond values of idle state parameters in accordance with their nanosecond values if they are provided (Rafael Wysocki) - Make the PSCI cpuidle driver prevent topology CPUs from being suspended on PREEMPT_RT (Krzysztof Kozlowski) - Document that pm_runtime_force_suspend() cannot be used with DPM_FLAG_SMART_SUSPEND (Richard Fitzgerald) - Add EXPORT macros for exporting PM functions from drivers (Richard Fitzgerald) - Remove /** from non-kernel-doc comments in hibernation code (Randy Dunlap) - Fix possible name leak in powercap_register_zone() (Yang Yingliang) - Add Meteor Lake and Emerald Rapids support to the intel_rapl power capping driver (Zhang Rui) - Modify the idle_inject power capping facility to support 100% idle injection (Srinivas Pandruvada) - Fix large time windows handling in the intel_rapl power capping driver (Zhang Rui) - Fix memory leaks with using debugfs_lookup() in the generic PM domains and Energy Model code (Greg Kroah-Hartman) - Add missing 'cache-unified' property in the example for kryo OPP bindings (Rob Herring) - Fix error checking in opp_migrate_dentry() (Qi Zheng) - Let qcom,opp-fuse-level be a 2-long array for qcom SoCs (Konrad Dybcio) - Modify some power management utilities to use the canonical ftrace path (Ross Zwisler) - Correct spelling problems for Documentation/power/ as reported by codespell (Randy Dunlap)" * tag 'pm-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (53 commits) Documentation: amd-pstate: disambiguate user space sections cpufreq: amd-pstate: Fix invalid write to MSR_AMD_CPPC_REQ dt-bindings: opp: opp-v2-kryo-cpu: enlarge opp-supported-hw maximum dt-bindings: cpufreq: qcom-cpufreq-nvmem: make cpr bindings optional dt-bindings: cpufreq: qcom-cpufreq-nvmem: specify supported opp tables PM: Add EXPORT macros for exporting PM functions cpuidle: psci: Do not suspend topology CPUs on PREEMPT_RT MIPS: loongson32: Drop obsolete cpufreq platform device powercap: intel_rapl: Fix handling for large time window cpuidle: driver: Update microsecond values of state parameters as needed cpuidle: sysfs: make kobj_type structures constant cpuidle: add ARCH_SUSPEND_POSSIBLE dependencies PM: EM: fix memory leak with using debugfs_lookup() PM: domains: fix memory leak with using debugfs_lookup() cpufreq: Make kobj_type structure constant cpufreq: davinci: Fix clk use after free cpufreq: amd-pstate: avoid uninitialized variable use cpufreq: Make cpufreq_unregister_driver() return void OPP: fix error checking in opp_migrate_dentry() dt-bindings: cpufreq: cpufreq-qcom-hw: Add SM8550 compatible ...
2023-01-13PM: runtime: Document that force_suspend() is incompatible with SMART_SUSPENDRichard Fitzgerald
pm_runtime_force_suspend() cannot be used with DPM_FLAG_SMART_SUSPEND, so note this in the kerneldoc. If DPM_FLAG_SMART_SUSPEND is set and the PM core cannot skip system resume it will call pm_runtime_active() on the driver. This can lead to an inconsistent state where: pm_runtime_force_suspend() called ->runtime_suspend but device_resume_noirq() called pm_runtime_set_active() This leaves the driver actually suspended but marked as active. Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-01-13cpuidle, ARM: OMAP2+: powerdomain: Remove trace_.*_rcuidle()Peter Zijlstra
OMAP was the one and only user. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20230112195541.782536366@infradead.org
2022-12-07PM: runtime: Adjust white space in the core codeRafael J. Wysocki
Some inconsistent usage of white space in the PM-runtime core code causes that code to be somewhat harder to read that it would have been otherwise, so adjust the white space in there to be more consistent with the rest of the code. No expected functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-12-05PM: runtime: Relocate rpm_callback() right after __rpm_callback()Rafael J. Wysocki
Because rpm_callback() is a wrapper around __rpm_callback(), and the only caller of it after the change eliminating an invocation of it from rpm_idle(), move the former next to the latter to make the code a bit easier to follow. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
2022-12-05PM: runtime: Do not call __rpm_callback() from rpm_idle()Rafael J. Wysocki
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 <rafael.j.wysocki@intel.com> Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
2022-09-24PM: runtime: Return -EINPROGRESS from rpm_resume() in the RPM_NOWAIT caseRafael J. Wysocki
The prospective callers of rpm_resume() passing RPM_NOWAIT to it may be confused when it returns 0 without actually resuming the device which may happen if the device is suspending at the given time and it will only resume when the suspend in progress has completed. To avoid that confusion, return -EINPROGRESS from rpm_resume() in that case. Since none of the current callers passing RPM_NOWAIT to rpm_resume() check its return value, this change has no functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reviewed-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2022-07-08PM: runtime: Extend support for wakeirq for force_suspend|resumeUlf Hansson
A driver that makes use of pm_runtime_force_suspend|resume() to support system suspend/resume, currently needs to manage the wakeirq support itself. To avoid the boilerplate code in the driver's system suspend/resume callbacks in particular, let's extend pm_runtime_force_suspend|resume() to deal with the wakeirq. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-07-01PM: runtime: Fix supplier device management during consumer probeRafael J. Wysocki
Because pm_runtime_get_suppliers() bumps up the rpm_active counter of each device link to a supplier of the given device in addition to bumping up the supplier's PM-runtime usage counter, a runtime suspend of the consumer device may case the latter to go down to 0 when pm_runtime_put_suppliers() is running on a remote CPU. If that happens after pm_runtime_put_suppliers() has released power.lock for the consumer device, and a runtime resume of that device takes place immediately after it, before pm_runtime_put() is called for the supplier, that pm_runtime_put() call may cause the supplier to be suspended even though the consumer is active. To prevent that from happening, modify pm_runtime_get_suppliers() to call pm_runtime_get_sync() for the given device's suppliers without touching the rpm_active counters of the involved device links Accordingly, modify pm_runtime_put_suppliers() to call pm_runtime_put() for the given device's suppliers without looking at the rpm_active counters of the device links at hand. [This is analogous to what happened before commit 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance").] Since pm_runtime_get_suppliers() sets supplier_preactivated for each device link where the supplier's PM-runtime usage counter has been incremented and pm_runtime_put_suppliers() calls pm_runtime_put() for the suppliers whose device links have supplier_preactivated set, the PM-runtime usage counter is balanced for each supplier and this is independent of the runtime suspend and resume of the consumer device. However, in case a device link with DL_FLAG_PM_RUNTIME set is dropped during the consumer device probe, so pm_runtime_get_suppliers() bumps up the supplier's PM-runtime usage counter, but it cannot be dropped by pm_runtime_put_suppliers(), make device_link_release_fn() take care of that. Fixes: 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance") Reported-by: Peter Wang <peter.wang@mediatek.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Peter Wang <peter.wang@mediatek.com> Cc: 5.1+ <stable@vger.kernel.org> # 5.1+
2022-07-01PM: runtime: Redefine pm_runtime_release_supplier()Rafael J. Wysocki
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 <gregkh@linuxfoundation.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: 5.1+ <stable@vger.kernel.org> # 5.1+
2022-05-23Merge branches 'pm-core', 'pm-sleep' and 'powercap'Rafael J. Wysocki
Merge PM core changes, updates related to system sleep and power capping updates for 5.19-rc1: - Export dev_pm_ops instead of suspend() and resume() in the IIO chemical scd30 driver (Jonathan Cameron). - Add namespace variants of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and PM-runtime counterparts (Jonathan Cameron). - Move symbol exports in the IIO chemical scd30 driver into the IIO_SCD30 namespace (Jonathan Cameron). - Avoid device PM-runtime usage count underflows (Rafael Wysocki). - Allow dynamic debug to control printing of PM messages (David Cohen). - Fix some kernel-doc comments in hibernation code (Yang Li, Haowen Bai). - Preserve ACPI-table override during hibernation (Amadeusz Sławiński). - Improve support for suspend-to-RAM for PSCI OSI mode (Ulf Hansson). - Make Intel RAPL power capping driver support the RaptorLake and AlderLake N processors (Zhang Rui, Sumeet Pawnikar). - Remove redundant store to value after multiply in the RAPL power capping driver (Colin Ian King). * pm-core: PM: runtime: Avoid device usage count underflows iio: chemical: scd30: Move symbol exports into IIO_SCD30 namespace PM: core: Add NS varients of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and runtime pm equiv iio: chemical: scd30: Export dev_pm_ops instead of suspend() and resume() * pm-sleep: cpuidle: PSCI: Improve support for suspend-to-RAM for PSCI OSI mode PM: runtime: Allow to call __pm_runtime_set_status() from atomic context PM: hibernate: Don't mark comment as kernel-doc x86/ACPI: Preserve ACPI-table override during hibernation PM: hibernate: Fix some kernel-doc comments PM: sleep: enable dynamic debug support within pm_pr_dbg() PM: sleep: Narrow down -DDEBUG on kernel/power/ files * powercap: powercap: intel_rapl: remove redundant store to value after multiply powercap: intel_rapl: add support for ALDERLAKE_N powercap: RAPL: Add Power Limit4 support for RaptorLake powercap: intel_rapl: add support for RaptorLake
2022-04-19PM: runtime: Allow to call __pm_runtime_set_status() from atomic contextUlf Hansson
The only two users of __pm_runtime_set_status() are pm_runtime_set_active() and pm_runtime_set_suspended(). These are widely used and should be called from non-atomic context to work as expected. However, it would be convenient to allow them be called from atomic context too, as shown from a subsequent change, so let's add support for this. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Maulik Shah <quic_mkshah@quicinc.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13PM: runtime: Avoid device usage count underflowsRafael J. Wysocki
A PM-runtime device usage count underflow is potentially critical, because it may cause a device to be suspended when it is expected to be operational. It is also a programming problem that would be good to catch and warn about. For this reason, (1) make rpm_check_suspend_allowed() return an error when the device usage count is negative to prevent devices from being suspended in that case, (2) introduce rpm_drop_usage_count() that will detect device usage count underflows, warn about them and fix them up, and (3) use it to drop the usage count in a few places instead of atomic_dec_and_test(). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2022-03-04PM: runtime: Have devm_pm_runtime_enable() handle ↵Douglas Anderson
pm_runtime_dont_use_autosuspend() 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 <laurent.pinchart@ideasonboard.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-22PM: runtime: Simplify locking in pm_runtime_put_suppliers()Rafael J. Wysocki
Notice that pm_runtime_put_suppliers() cannot be called with disabled interrupts, because it may sleep (due to the device links read locking in the non-SRCU case), and so it can use spin_lock_irq() and spin_unlock_irq() for the locking. Update the function accordingly and while at it move the "put" local variable in it into the inner block where it is used. This change is not expected to have any visible functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2021-12-17PM: runtime: Add safety net to supplier device releaseRafael J. Wysocki
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 <peterz@infradead.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-12-17PM: runtime: Capture device status before disabling runtime PMRafael J. Wysocki
In some cases (for example, during system-wide suspend and resume of devices) it is useful to know whether or not runtime PM has ever been enabled for a given device and, if so, what the runtime PM status of it had been right before runtime PM was disabled for it last time. For this reason, introduce a new struct dev_pm_info field called last_status that will be used for capturing the runtime PM status of the device when its power.disable_depth counter changes from 0 to 1. The new field will be set to RPM_INVALID to start with and whenever power.disable_depth changes from 1 to 0, so it will be valid only when runtime PM of the device is currently disabled, but it has been enabled at least once. Immediately use power.last_status in rpm_resume() to make it handle the case when PM runtime is disabled for the device, but its runtime PM status is RPM_ACTIVE more consistently. Namely, make it return 1 if power.last_status is also equal to RPM_ACTIVE in that case (the idea being that if the status was RPM_ACTIVE last time when power.disable_depth was changing from 0 to 1 and it is still RPM_ACTIVE, it can be assumed to reflect what happened to the device last time when it was using runtime PM) and -EACCES otherwise. Update the documentation to provide a description of last_status and change the description of pm_runtime_resume() in it to reflect the new behavior of rpm_active(). While at it, rearrange the code in pm_runtime_enable() to be more straightforward and replace the WARN() macro in it with a pr_warn() invocation which is less disruptive. Link: https://lore.kernel.org/linux-pm/20211026222626.39222-1-ulf.hansson@linaro.org/t/#u Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-10-27PM / wakeirq: support enabling wake-up irq after runtime_suspend calledChunfeng Yun
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 <rafael.j.wysocki@intel.com> Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-08-26PM: runtime: add devm_pm_runtime_enable helperDmitry Baryshkov
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 <dmitry.baryshkov@linaro.org> Link: https://lore.kernel.org/r/20210731195034.979084-2-dmitry.baryshkov@linaro.org Acked-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-06-11PM: runtime: Allow unassigned ->runtime_suspend|resume callbacksUlf Hansson
We are currently allowing ->runtime_idle() callbacks to be unassigned without returning an error code from rpm_idle(). This has been useful to avoid boilerplate code in drivers. Let's take this approach a step further, by allowing also unassigned ->runtime_suspend|resume() callbacks. In this way, a consumer/supplier device link can be used to let a consumer device be power managed through its supplier device, without requiring assigned ->runtime_suspend|resume() callbacks for the consumer device, for example. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-11PM: runtime: Improve path in rpm_idle() when no callbackUlf Hansson
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 <ulf.hansson@linaro.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-05-10PM: runtime: Fix unpaired parent child_count for force_resumeTony Lindgren
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 <tony@atomide.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Cc: 4.16+ <stable@vger.kernel.org> # 4.16+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-07PM: runtime: remove kernel-doc warningsPierre-Louis Bossart
remove make W=1 warnings drivers/base/power/runtime.c:926: warning: Function parameter or member 'timer' not described in 'pm_suspend_timer_fn' drivers/base/power/runtime.c:926: warning: Excess function parameter 'data' description in 'pm_suspend_timer_fn' Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-03-29PM: runtime: Fix race getting/putting suppliers at probeAdrian Hunter
pm_runtime_put_suppliers() must not decrement rpm_active unless the consumer is suspended. That is because, otherwise, it could suspend suppliers for an active consumer. That can happen as follows: static int driver_probe_device(struct device_driver *drv, struct device *dev) { int ret = 0; if (!device_is_registered(dev)) return -ENODEV; dev->can_match = true; pr_debug("bus: '%s': %s: matched device %s with driver %s\n", drv->bus->name, __func__, dev_name(dev), drv->name); pm_runtime_get_suppliers(dev); if (dev->parent) pm_runtime_get_sync(dev->parent); At this point, dev can runtime suspend so rpm_put_suppliers() can run, rpm_active becomes 1 (the lowest value). pm_runtime_barrier(dev); if (initcall_debug) ret = really_probe_debug(dev, drv); else ret = really_probe(dev, drv); Probe callback can have runtime resumed dev, and then runtime put so dev is awaiting autosuspend, but rpm_active is 2. pm_request_idle(dev); if (dev->parent) pm_runtime_put(dev->parent); pm_runtime_put_suppliers(dev); Now pm_runtime_put_suppliers() will put the supplier i.e. rpm_active 2 -> 1, but consumer can still be active. return ret; } Fix by checking the runtime status. For any status other than RPM_SUSPENDED, rpm_active can be considered to be "owned" by rpm_[get/put]_suppliers() and pm_runtime_put_suppliers() need do nothing. Reported-by: Asutosh Das <asutoshd@codeaurora.org> Fixes: 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance") Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: 5.1+ <stable@vger.kernel.org> # 5.1+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-03-29PM: runtime: Fix ordering in pm_runtime_get_suppliers()Adrian Hunter
rpm_active indicates how many times the supplier usage_count has been incremented. Consequently it must be updated after pm_runtime_get_sync() of the supplier, not before. Fixes: 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance") Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: 5.1+ <stable@vger.kernel.org> # 5.1+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-03-22PM: runtime: Defer suspending suppliersRafael J. Wysocki
Because the PM-runtime status of the device is not updated in __rpm_callback(), attempts to suspend the suppliers of the given device triggered by the rpm_put_suppliers() call in there may cause a supplier to be suspended completely before the status of the consumer is updated to RPM_SUSPENDED, which is confusing. To avoid that (1) modify __rpm_callback() to only decrease the PM-runtime usage counter of each supplier and (2) make rpm_suspend() try to suspend the suppliers after changing the consumer's status to RPM_SUSPENDED, in analogy with the device's parent. Link: https://lore.kernel.org/linux-pm/CAPDyKFqm06KDw_p8WXsM4dijDbho4bb6T4k50UqqvR1_COsp8g@mail.gmail.com/ Fixes: 21d5c57b3726 ("PM / runtime: Use device links") Reported-by: elaine.zhang <zhangqing@rock-chips.com> Diagnosed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-03-19Revert "PM: runtime: Update device status before letting suppliers suspend"Rafael J. Wysocki
Revert commit 44cc89f76464 ("PM: runtime: Update device status before letting suppliers suspend") that introduced a race condition into __rpm_callback() which allowed a concurrent rpm_resume() to run and resume the device prematurely after its status had been changed to RPM_SUSPENDED by __rpm_callback(). Fixes: 44cc89f76464 ("PM: runtime: Update device status before letting suppliers suspend") Link: https://lore.kernel.org/linux-pm/24dfb6fc-5d54-6ee2-9195-26428b7ecf8a@intel.com/ Reported-by: Adrian Hunter <adrian.hunter@intel.com> Cc: 4.10+ <stable@vger.kernel.org> # 4.10+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2021-03-01PM: runtime: Update device status before letting suppliers suspendRafael J. Wysocki
Because the PM-runtime status of the device is not updated in __rpm_callback(), attempts to suspend the suppliers of the given device triggered by rpm_put_suppliers() called by it may fail. Fix this by making __rpm_callback() update the device's status to RPM_SUSPENDED before calling rpm_put_suppliers() if the current status of the device is RPM_SUSPENDING and the callback just invoked by it has returned 0 (success). While at it, modify the code in __rpm_callback() to always check the device's PM-runtime status under its PM lock. Link: https://lore.kernel.org/linux-pm/CAPDyKFqm06KDw_p8WXsM4dijDbho4bb6T4k50UqqvR1_COsp8g@mail.gmail.com/ Fixes: 21d5c57b3726 ("PM / runtime: Use device links") Reported-by: Elaine Zhang <zhangqing@rock-chips.com> Diagnosed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Elaine Zhang <zhangiqng@rock-chips.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Cc: 4.10+ <stable@vger.kernel.org> # 4.10+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-22PM: runtime: Fix resposible -> responsible in runtime.cBhaskar Chowdhury
s/resposible/responsible/ Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> [ rjw: Subject edit ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-02PM: runtime: Drop pm_runtime_clean_up_links()Rafael J. Wysocki
After commit d12544fb2aa9 ("PM: runtime: Remove link state checks in rpm_get/put_supplier()") nothing prevents the consumer device's runtime PM from acquiring additional references to the supplier device after pm_runtime_clean_up_links() has run (or even while it is running), so calling this function from __device_release_driver() may be pointless (or even harmful). Moreover, it ignores stateless device links, so the runtime PM handling of managed and stateless device links is inconsistent because of it, so better get rid of it entirely. Fixes: d12544fb2aa9 ("PM: runtime: Remove link state checks in rpm_get/put_supplier()") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: 5.1+ <stable@vger.kernel.org> # 5.1+ Tested-by: Xiang Chen <chenxiang66@hisilicon.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-02PM: runtime: Drop runtime PM references to supplier on link removalRafael J. Wysocki
While removing a device link, drop the supplier device's runtime PM usage counter as many times as needed to drop all of the runtime PM references to it from the consumer in addition to dropping the consumer's link count. Fixes: baa8809f6097 ("PM / runtime: Optimize the use of device links") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: 5.1+ <stable@vger.kernel.org> # 5.1+ Tested-by: Xiang Chen <chenxiang66@hisilicon.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-25PM: runtime: Remove link state checks in rpm_get/put_supplier()Xiang Chen
To support runtime PM for hisi SAS driver (the driver is in directory drivers/scsi/hisi_sas), we add device link between scsi_device->sdev_gendev (consumer device) and hisi_hba->dev(supplier device) with flags DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE. After runtime suspended consumers and supplier, unload the dirver which causes a hung. We found that it called function device_release_driver_internal() to release the supplier device (hisi_hba->dev), as the device link was busy, it set the device link state to DL_STATE_SUPPLIER_UNBIND, and then it called device_release_driver_internal() to release the consumer device (scsi_device->sdev_gendev). Then it would try to call pm_runtime_get_sync() to resume the consumer device, but because consumer-supplier relation existed, it would try to resume the supplier first, but as the link state was already DL_STATE_SUPPLIER_UNBIND, so it skipped resuming the supplier and only resumed the consumer which hanged (it sends IOs to resume scsi_device while the SAS controller is suspended). Simple flow is as follows: device_release_driver_internal -> (supplier device) if device_links_busy -> device_links_unbind_consumers -> ... WRITE_ONCE(link->status, DL_STATE_SUPPLIER_UNBIND) device_release_driver_internal (consumer device) pm_runtime_get_sync -> (consumer device) ... __rpm_callback -> rpm_get_suppliers -> if link->state == DL_STATE_SUPPLIER_UNBIND -> skip the action of resuming the supplier ... pm_runtime_clean_up_links ... Correct suspend/resume ordering between a supplier device and its consumer devices (resume the supplier device before resuming consumer devices, and suspend consumer devices before suspending the supplier device) should be guaranteed by runtime PM, but the state checks in rpm_get_supplier() and rpm_put_supplier() break this rule, so remove them. Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com> [ rjw: Subject and changelog edits ] Cc: All applicable <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-08-04PM: runtime: Improve kerneldoc of pm_runtime_get_if_active()Rafael J. Wysocki
The kerneldoc comment of pm_runtime_get_if_active() doesn't list the second argument of the function properly, so fix that and while at it clarify that comment somewhat and add some markup to it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>