[PATCH v2 2/4] PM: runtime: Introduce pm_runtime_blocked()
From: Rafael J. Wysocki <hidden>
Date: 2025-02-18 20:21:01
Also in:
linux-acpi, linux-pci, lkml
From: Rafael J. Wysocki <redacted> 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 <redacted> Reviewed-by: Ulf Hansson <redacted> --- v1 -> v2: Add the R-by, no other changes. --- drivers/base/power/runtime.c | 17 +++++++++++++++++ include/linux/pm_runtime.h | 2 ++ 2 files changed, 19 insertions(+)
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c@@ -1555,6 +1555,23 @@ } EXPORT_SYMBOL_GPL(pm_runtime_enable); +bool pm_runtime_blocked(struct device *dev) +{ + bool ret; + + /* + * dev->power.last_status is a bit field, so in case it is updated via + * RMW, read it under the spin lock. + */ + spin_lock_irq(&dev->power.lock); + + ret = dev->power.last_status == RPM_BLOCKED; + + spin_unlock_irq(&dev->power.lock); + + return ret; +} + static void pm_runtime_disable_action(void *data) { pm_runtime_dont_use_autosuspend(data); --- a/include/linux/pm_runtime.h +++ b/include/linux/pm_runtime.h
@@ -81,6 +81,7 @@ extern void pm_runtime_unblock(struct device *dev); extern void pm_runtime_enable(struct device *dev); extern void __pm_runtime_disable(struct device *dev, bool check_resume); +extern bool pm_runtime_blocked(struct device *dev); extern void pm_runtime_allow(struct device *dev); extern void pm_runtime_forbid(struct device *dev); extern void pm_runtime_no_callbacks(struct device *dev);
@@ -277,6 +278,7 @@ static inline void pm_runtime_unblock(struct device *dev) {} static inline void pm_runtime_enable(struct device *dev) {} static inline void __pm_runtime_disable(struct device *dev, bool c) {} +static inline bool pm_runtime_blocked(struct device *dev) { return true; } static inline void pm_runtime_allow(struct device *dev) {} static inline void pm_runtime_forbid(struct device *dev) {}