linux-kernel - Re: [PATCH v1 4/9] PM: Move pm_runtime_force_suspend/resume() under CONFIG_PM

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Message-ID: <CAPDyKFq8ea+YogkAExUOBc2TEqi1z9WZswqgP29bLbursFUApg@mail.gmail.com>
Date: Thu, 26 Jun 2025 11:38:08 +0200
From: Ulf Hansson <ulf.hansson@...aro.org>
To: "Rafael J. Wysocki" <rjw@...ysocki.net>
Cc: Linux PM <linux-pm@...r.kernel.org>, LKML <linux-kernel@...r.kernel.org>, 
	Linux ACPI <linux-acpi@...r.kernel.org>, Linux PCI <linux-pci@...r.kernel.org>, 
	Mika Westerberg <mika.westerberg@...ux.intel.com>
Subject: Re: [PATCH v1 4/9] PM: Move pm_runtime_force_suspend/resume() under CONFIG_PM_SLEEP

On Wed, 25 Jun 2025 at 21:25, Rafael J. Wysocki <rjw@...ysocki.net> wrote:
>
> From: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
>
> Since pm_runtime_force_suspend/resume() and pm_runtime_need_not_resume()
> are only used during system-wide PM transitions, there is no reason to
> compile them in if CONFIG_PM_SLEEP is unset.
>
> Accordingly, move them all under CONFIG_PM_SLEEP and make the static
> inline stubs for pm_runtime_force_suspend/resume() return an error
> to indicate that they should not be used outside CONFIG_PM_SLEEP.
>

Just realized that there seems to be some drivers that actually make
use of pm_runtime_force_suspend() from their ->remove() callbacks.

To not break them, we probably need to leave this code to stay under CONFIG_PM.

Kind regards
Uffe

> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
> ---
>  drivers/base/power/runtime.c |    4 ++++
>  include/linux/pm_runtime.h   |   20 ++++++++++++++------
>  2 files changed, 18 insertions(+), 6 deletions(-)
>
> --- a/drivers/base/power/runtime.c
> +++ b/drivers/base/power/runtime.c
> @@ -1941,6 +1941,8 @@
>         pm_request_idle(link->supplier);
>  }
>
> +#ifdef CONFIG_PM_SLEEP
> +
>  bool pm_runtime_need_not_resume(struct device *dev)
>  {
>         return atomic_read(&dev->power.usage_count) <= 1 &&
> @@ -2063,3 +2065,5 @@
>         return ret;
>  }
>  EXPORT_SYMBOL_GPL(pm_runtime_force_resume);
> +
> +#endif /* CONFIG_PM_SLEEP */
> --- a/include/linux/pm_runtime.h
> +++ b/include/linux/pm_runtime.h
> @@ -66,9 +66,6 @@
>
>  extern int pm_generic_runtime_suspend(struct device *dev);
>  extern int pm_generic_runtime_resume(struct device *dev);
> -extern bool pm_runtime_need_not_resume(struct device *dev);
> -extern int pm_runtime_force_suspend(struct device *dev);
> -extern int pm_runtime_force_resume(struct device *dev);
>
>  extern int __pm_runtime_idle(struct device *dev, int rpmflags);
>  extern int __pm_runtime_suspend(struct device *dev, int rpmflags);
> @@ -257,9 +254,6 @@
>
>  static inline int pm_generic_runtime_suspend(struct device *dev) { return 0; }
>  static inline int pm_generic_runtime_resume(struct device *dev) { return 0; }
> -static inline bool pm_runtime_need_not_resume(struct device *dev) {return true; }
> -static inline int pm_runtime_force_suspend(struct device *dev) { return 0; }
> -static inline int pm_runtime_force_resume(struct device *dev) { return 0; }
>
>  static inline int __pm_runtime_idle(struct device *dev, int rpmflags)
>  {
> @@ -330,6 +324,20 @@
>
>  #endif /* !CONFIG_PM */
>
> +#ifdef CONFIG_PM_SLEEP
> +
> +extern bool pm_runtime_need_not_resume(struct device *dev);
> +extern int pm_runtime_force_suspend(struct device *dev);
> +extern int pm_runtime_force_resume(struct device *dev);
> +
> +#else /* !CONFIG_PM_SLEEP */
> +
> +static inline bool pm_runtime_need_not_resume(struct device *dev) {return true; }
> +static inline int pm_runtime_force_suspend(struct device *dev) { return -ENXIO; }
> +static inline int pm_runtime_force_resume(struct device *dev) { return -ENXIO; }
> +
> +#endif /* CONFIG_PM_SLEEP */
> +
>  /**
>   * pm_runtime_idle - Conditionally set up autosuspend of a device or suspend it.
>   * @dev: Target device.
>
>
>