> Add devfreq suspend/resume apis for devfreq users. This patch
> supports suspend and resume of devfreq load monitoring, required
> for devices which can idle.
>
> Signed-off-by: Rajagopal Venkat <rajagopal.venkat@linaro.org>

Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>

> ---
>  drivers/devfreq/devfreq.c                 | 28 ++++++++++++++++++++++++++++
>  drivers/devfreq/governor.h                |  2 ++
>  drivers/devfreq/governor_simpleondemand.c |  9 +++++++++
>  include/linux/devfreq.h                   | 12 ++++++++++++
>  4 files changed, 51 insertions(+)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 8e9b5aa..edddb9e 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -416,6 +416,34 @@ int devfreq_remove_device(struct devfreq *devfreq)
>  }
>  EXPORT_SYMBOL(devfreq_remove_device);
> 
> +/**
> + * devfreq_suspend_device() - Suspend devfreq of a device.
> + * @devfreq the devfreq instance to be suspended
> + */
> +int devfreq_suspend_device(struct devfreq *devfreq)
> +{
> + if (!devfreq)
> +  return -EINVAL;
> +
> + return devfreq->governor->event_handler(devfreq,
> +    DEVFREQ_GOV_SUSPEND, NULL);
> +}
> +EXPORT_SYMBOL(devfreq_suspend_device);
> +
> +/**
> + * devfreq_resume_device() - Resume devfreq of a device.
> + * @devfreq the devfreq instance to be resumed
> + */
> +int devfreq_resume_device(struct devfreq *devfreq)
> +{
> + if (!devfreq)
> +  return -EINVAL;
> +
> + return devfreq->governor->event_handler(devfreq,
> +    DEVFREQ_GOV_RESUME, NULL);
> +}
> +EXPORT_SYMBOL(devfreq_resume_device);
> +
>  static ssize_t show_governor(struct device *dev,
>          struct device_attribute *attr, char *buf)
>  {
> diff --git a/drivers/devfreq/governor.h b/drivers/devfreq/governor.h
> index bb3aff3..26432ac 100644
> --- a/drivers/devfreq/governor.h
> +++ b/drivers/devfreq/governor.h
> @@ -22,6 +22,8 @@
>  #define DEVFREQ_GOV_START   0x1
>  #define DEVFREQ_GOV_STOP   0x2
>  #define DEVFREQ_GOV_INTERVAL   0x3
> +#define DEVFREQ_GOV_SUSPEND   0x4
> +#define DEVFREQ_GOV_RESUME   0x5
> 
>  /* Caution: devfreq->lock must be locked before calling update_devfreq */
>  extern int update_devfreq(struct devfreq *devfreq);
> diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c
> index cf94218..a8ba78c 100644
> --- a/drivers/devfreq/governor_simpleondemand.c
> +++ b/drivers/devfreq/governor_simpleondemand.c
> @@ -104,6 +104,15 @@ int devfreq_simple_ondemand_handler(struct devfreq *devfreq,
>   case DEVFREQ_GOV_INTERVAL:
>    devfreq_interval_update(devfreq, (unsigned int *)data);
>    break;
> +
> + case DEVFREQ_GOV_SUSPEND:
> +  devfreq_monitor_suspend(devfreq);
> +  break;
> +
> + case DEVFREQ_GOV_RESUME:
> +  devfreq_monitor_resume(devfreq);
> +  break;
> +
>   default:
>    break;
>   }
> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
> index 2ab70e3..18bd3b7 100644
> --- a/include/linux/devfreq.h
> +++ b/include/linux/devfreq.h
> @@ -158,6 +158,8 @@ extern struct devfreq *devfreq_add_device(struct device *dev,
>        const struct devfreq_governor *governor,
>        void *data);
>  extern int devfreq_remove_device(struct devfreq *devfreq);
> +extern int devfreq_suspend_device(struct devfreq *devfreq);
> +extern int devfreq_resume_device(struct devfreq *devfreq);
> 
>  /* Helper functions for devfreq user device driver with OPP. */
>  extern struct opp *devfreq_recommended_opp(struct device *dev,
> @@ -211,6 +213,16 @@ static int devfreq_remove_device(struct devfreq *devfreq)
>   return 0;
>  }
> 
> +static int devfreq_suspend_device(struct devfreq *devfreq)
> +{
> + return 0;
> +}
> +
> +static int devfreq_resume_device(struct devfreq *devfreq)
> +{
> + return 0;
> +}
> +
>  static struct opp *devfreq_recommended_opp(struct device *dev,
>          unsigned long *freq, u32 flags)
>  {
> --
> 1.7.11.3
>
>
>
>
>       
>  
>