[PATCH/RFC v2 04/12] PM / Domains: Add genpd attach/detach callbacks

[Ulf Hansson]

On 16 September 2014 20:48, Geert Uytterhoeven <geert+renesas at glider.be> wrote:
> While a PM domain can enable PM runtime management of its devices' module
> clocks by setting
>
>         genpd->dev_ops.stop = pm_clk_suspend;
>         genpd->dev_ops.start = pm_clk_resume;
>
> this also requires registering the clocks with the pm_clk subsystem.
> In the legacy case, this is handled by the platform code, after
> attaching the device to its PM domain.
>
> When the devices are instantiated from DT, devices are attached to their
> PM domains by generic code, leaving no method for the platform-specific
> PM domain code to register their clocks.
>
> Add two callbacks, allowing a PM domain to perform platform-specific
> tasks when a device is attached to or detached from a PM domain.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>
> ---
> v2:
>   - New
> ---
>  drivers/base/power/domain.c | 12 ++++++++++++
>  include/linux/pm_domain.h   |  2 ++
>  2 files changed, 14 insertions(+)
>
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index f09b615e61515d11..3fa15b6c54f09b36 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -1418,6 +1418,12 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
>         if (ret)
>                 goto out;
>
> +       if (genpd->attach_dev) {
> +               ret = genpd->attach_dev(genpd, dev);
> +               if (ret)
> +                       goto out;
> +       }
> +
>         genpd->device_count++;
>         genpd->max_off_time_changed = true;
>
> @@ -1541,6 +1547,12 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
>
>         spin_unlock_irq(&dev->power.lock);
>
> +       if (genpd->detach_dev) {
> +               ret = genpd->detach_dev(genpd, dev);
> +               if (ret)
> +                       goto out;
> +       }
> +
>         mutex_lock(&gpd_data->lock);
>         pdd->dev = NULL;
>         mutex_unlock(&gpd_data->lock);
> diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
> index ff128c1ec0de231c..ac07918f907b7495 100644
> --- a/include/linux/pm_domain.h
> +++ b/include/linux/pm_domain.h
> @@ -73,6 +73,8 @@ struct generic_pm_domain {
>         bool cached_power_down_ok;
>         struct device_node *of_node; /* Node in device tree */
>         struct gpd_cpu_data *cpu_data;
> +       int (*attach_dev)(struct generic_pm_domain *domain, struct device *dev);
> +       int (*detach_dev)(struct generic_pm_domain *domain, struct device *dev);
>  };
>
>  static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)
> --
> 1.9.1
>


This is great stuff, exactly what I had in mind! :-)

Reviewed-by: Ulf Hansson <ulf.hansson at linaro.org>