Re: [PATCH v2] ACPI / PM: Combine device suspend routines

[Ulf Hansson]

On 14 October 2017 at 17:43, Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> On top of a previous change getting rid of the PM QoS flag
> PM_QOS_FLAG_REMOTE_WAKEUP, combine two ACPI device suspend routines,
> acpi_dev_runtime_suspend() and acpi_dev_suspend_late(), into one,
> acpi_dev_suspend(), to eliminate some code duplication.
>
> It also avoids enabling wakeup for devices handled by the ACPI
> LPSS middle layer on driver removal.
>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Nice work and cleanup!

Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>

> ---
>
> -> v2: Drop a previously missed acpi_dev_runtime_suspend() header.
>
> ---
>  drivers/acpi/acpi_lpss.c |    6 ++--
>  drivers/acpi/device_pm.c |   61 ++++++++++-------------------------------------
>  include/linux/acpi.h     |    3 --
>  3 files changed, 18 insertions(+), 52 deletions(-)
>
> Index: linux-pm/drivers/acpi/device_pm.c
> ===================================================================
> --- linux-pm.orig/drivers/acpi/device_pm.c
> +++ linux-pm/drivers/acpi/device_pm.c
> @@ -847,37 +847,39 @@ static int acpi_dev_pm_full_power(struct
>  }
>
>  /**
> - * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI.
> + * acpi_dev_suspend - Put device into a low-power state using ACPI.
>   * @dev: Device to put into a low-power state.
> + * @wakeup: Whether or not to enable wakeup for the device.
>   *
> - * Put the given device into a runtime low-power state using the standard ACPI
> + * Put the given device into a low-power state using the standard ACPI
>   * mechanism.  Set up remote wakeup if desired, choose the state to put the
>   * device into (this checks if remote wakeup is expected to work too), and set
>   * the power state of the device.
>   */
> -int acpi_dev_runtime_suspend(struct device *dev)
> +int acpi_dev_suspend(struct device *dev, bool wakeup)
>  {
>         struct acpi_device *adev = ACPI_COMPANION(dev);
> -       bool remote_wakeup;
> +       u32 target_state = acpi_target_system_state();
>         int error;
>
>         if (!adev)
>                 return 0;
>
> -       remote_wakeup = acpi_device_can_wakeup(adev);
> -       if (remote_wakeup) {
> -               error = acpi_device_wakeup_enable(adev, ACPI_STATE_S0);
> +       if (wakeup && acpi_device_can_wakeup(adev)) {
> +               error = acpi_device_wakeup_enable(adev, target_state);
>                 if (error)
>                         return -EAGAIN;
> +       } else {
> +               wakeup = false;
>         }
>
> -       error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
> -       if (error && remote_wakeup)
> +       error = acpi_dev_pm_low_power(dev, adev, target_state);
> +       if (error && wakeup)
>                 acpi_device_wakeup_disable(adev);
>
>         return error;
>  }
> -EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend);
> +EXPORT_SYMBOL_GPL(acpi_dev_suspend);
>
>  /**
>   * acpi_dev_resume - Put device into the full-power state using ACPI.
> @@ -910,7 +912,7 @@ EXPORT_SYMBOL_GPL(acpi_dev_resume);
>  int acpi_subsys_runtime_suspend(struct device *dev)
>  {
>         int ret = pm_generic_runtime_suspend(dev);
> -       return ret ? ret : acpi_dev_runtime_suspend(dev);
> +       return ret ? ret : acpi_dev_suspend(dev, true);
>  }
>  EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
>
> @@ -929,41 +931,6 @@ int acpi_subsys_runtime_resume(struct de
>  EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
>
>  #ifdef CONFIG_PM_SLEEP
> -/**
> - * acpi_dev_suspend_late - Put device into a low-power state using ACPI.
> - * @dev: Device to put into a low-power state.
> - *
> - * Put the given device into a low-power state during system transition to a
> - * sleep state using the standard ACPI mechanism.  Set up system wakeup if
> - * desired, choose the state to put the device into (this checks if system
> - * wakeup is expected to work too), and set the power state of the device.
> - */
> -int acpi_dev_suspend_late(struct device *dev)
> -{
> -       struct acpi_device *adev = ACPI_COMPANION(dev);
> -       u32 target_state;
> -       bool wakeup;
> -       int error;
> -
> -       if (!adev)
> -               return 0;
> -
> -       target_state = acpi_target_system_state();
> -       wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev);
> -       if (wakeup) {
> -               error = acpi_device_wakeup_enable(adev, target_state);
> -               if (error)
> -                       return error;
> -       }
> -
> -       error = acpi_dev_pm_low_power(dev, adev, target_state);
> -       if (error && wakeup)
> -               acpi_device_wakeup_disable(adev);
> -
> -       return error;
> -}
> -EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
> -
>  static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
>  {
>         u32 sys_target = acpi_target_system_state();
> @@ -1046,7 +1013,7 @@ EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
>  int acpi_subsys_suspend_late(struct device *dev)
>  {
>         int ret = pm_generic_suspend_late(dev);
> -       return ret ? ret : acpi_dev_suspend_late(dev);
> +       return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));
>  }
>  EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
>
> Index: linux-pm/drivers/acpi/acpi_lpss.c
> ===================================================================
> --- linux-pm.orig/drivers/acpi/acpi_lpss.c
> +++ linux-pm/drivers/acpi/acpi_lpss.c
> @@ -713,7 +713,7 @@ static int acpi_lpss_activate(struct dev
>
>  static void acpi_lpss_dismiss(struct device *dev)
>  {
> -       acpi_dev_runtime_suspend(dev);
> +       acpi_dev_suspend(dev, false);
>  }
>
>  #ifdef CONFIG_PM_SLEEP
> @@ -729,7 +729,7 @@ static int acpi_lpss_suspend_late(struct
>         if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
>                 acpi_lpss_save_ctx(dev, pdata);
>
> -       return acpi_dev_suspend_late(dev);
> +       return acpi_dev_suspend(dev, device_may_wakeup(dev));
>  }
>
>  static int acpi_lpss_resume_early(struct device *dev)
> @@ -847,7 +847,7 @@ static int acpi_lpss_runtime_suspend(str
>         if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
>                 acpi_lpss_save_ctx(dev, pdata);
>
> -       ret = acpi_dev_runtime_suspend(dev);
> +       ret = acpi_dev_suspend(dev, true);
>
>         /*
>          * This call must be last in the sequence, otherwise PMC will return
> Index: linux-pm/include/linux/acpi.h
> ===================================================================
> --- linux-pm.orig/include/linux/acpi.h
> +++ linux-pm/include/linux/acpi.h
> @@ -864,7 +864,7 @@ static inline void arch_reserve_mem_area
>  #endif
>
>  #if defined(CONFIG_ACPI) && defined(CONFIG_PM)
> -int acpi_dev_runtime_suspend(struct device *dev);
> +int acpi_dev_suspend(struct device *dev, bool wakeup);
>  int acpi_dev_resume(struct device *dev);
>  int acpi_subsys_runtime_suspend(struct device *dev);
>  int acpi_subsys_runtime_resume(struct device *dev);
> @@ -889,7 +889,6 @@ int acpi_subsys_resume_early(struct devi
>  int acpi_subsys_suspend(struct device *dev);
>  int acpi_subsys_freeze(struct device *dev);
>  #else
> -static inline int acpi_dev_suspend_late(struct device *dev) { return 0; }
>  static inline int acpi_dev_resume_early(struct device *dev) { return 0; }
>  static inline int acpi_subsys_prepare(struct device *dev) { return 0; }
>  static inline void acpi_subsys_complete(struct device *dev) {}
>