Re: [PATCH 1/2] power: add new interface to return pm_transition state

From: Rafael J. Wysocki
Date: Sat Jun 22 2013 - 17:17:33 EST


On Saturday, June 22, 2013 02:11:14 PM Shuah Khan wrote:
> Add a new interface get_pm_transition() to return pm_transition state.
> This interface is intended to be used from dev_pm_ops class and type
> suspend interfaces that call legacy pm ops driver suspend interfaces.
> Legacy suspend pm_ops take pm_message_t as a parameter.
>
> e.g: drm_class_suspend() calls into driver suspend routines
> via drm_dev->driver->suspend(drm_dev, state).
>
> Once drm_class_suspend() is converted to dev_pm_ops, it will no longer
> have access to pm_transition which it has to pass into driver legacy
> suspend calls. get_pm_transition() interface addresses this need.

That shouldn't be necessary because each transition has its own callback
in strict dev_pm_ops.

Thanks,
Rafael


> Signed-off-by: Shuah Khan <shuah.kh@xxxxxxxxxxx>
> ---
> drivers/base/power/main.c | 17 +++++++++++++++++
> include/linux/pm.h | 3 +++
> 2 files changed, 20 insertions(+)
>
> diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
> index c2132b8..3e2e09d 100644
> --- a/drivers/base/power/main.c
> +++ b/drivers/base/power/main.c
> @@ -57,6 +57,23 @@ static pm_message_t pm_transition;
> static int async_error;
>
> /**
> + * get_pm_transition - return pm_transition state.
> + * This interface is intended to be used from dev_pm_ops class and type
> + * suspend interfaces that call legacy pm ops driver suspend interfaces.
> + * Legacy suspend pm_ops take pm_message_t as a parameter.
> + * e.g: drm_class_suspend() calls into driver suspend routines
> + * via drm_dev->driver->suspend(drm_dev, state).
> + * Once drm_class_suspend() is converted to dev_pm_ops, it will no longer
> + * have access to pm_transition which it has to pass into driver legacy
> + * suspend calls. get_pm_transition() interface addresses this need.
> +*/
> +pm_message_t get_pm_transition()
> +{
> + return pm_transition;
> +}
> +EXPORT_SYMBOL_GPL(get_pm_transition);
> +
> +/**
> * device_pm_sleep_init - Initialize system suspend-related device fields.
> * @dev: Device object being initialized.
> */
> diff --git a/include/linux/pm.h b/include/linux/pm.h
> index a224c7f..46f3252 100644
> --- a/include/linux/pm.h
> +++ b/include/linux/pm.h
> @@ -63,6 +63,9 @@ typedef struct pm_message {
> int event;
> } pm_message_t;
>
> +/* drivers/base/power/main.c */
> +extern pm_message_t get_pm_transition(void);
> +
> /**
> * struct dev_pm_ops - device PM callbacks
> *
>
--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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