Hi Dmitry,
On 19. 11. 5. 오전 6:56, Dmitry Osipenko wrote:
> Currently interrupt-driven governors (like NVIDIA Tegra30 ACTMON governor)
> are used to set polling_ms=0 in order to avoid periodic polling of device
> status by devfreq core. This means that polling interval can't be changed
> by userspace for such governors.
>
> The new governor flag allows interrupt-driven governors to convey that
> devfreq core shouldn't perform polling of device status and thus generic
> devfreq polling interval could be supported by these governors now.
>
> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
> ---
> drivers/devfreq/devfreq.c | 17 +++++++++++++++++
> drivers/devfreq/governor.h | 3 +++
> 2 files changed, 20 insertions(+)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index b905963cea7d..4eff37e8bb07 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -409,6 +409,9 @@ static void devfreq_monitor(struct work_struct *work)
> */
> void devfreq_monitor_start(struct devfreq *devfreq)
> {
> + if (devfreq->governor->interrupt_driven)
> + return;
> +
> INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor);
> if (devfreq->profile->polling_ms)
> queue_delayed_work(devfreq_wq, &devfreq->work,
> @@ -426,6 +429,9 @@ EXPORT_SYMBOL(devfreq_monitor_start);
> */
> void devfreq_monitor_stop(struct devfreq *devfreq)
> {
> + if (devfreq->governor->interrupt_driven)
> + return;
> +
> cancel_delayed_work_sync(&devfreq->work);
> }
> EXPORT_SYMBOL(devfreq_monitor_stop);
> @@ -453,6 +459,10 @@ void devfreq_monitor_suspend(struct devfreq *devfreq)
> devfreq_update_status(devfreq, devfreq->previous_freq);
> devfreq->stop_polling = true;
> mutex_unlock(&devfreq->lock);
> +
> + if (devfreq->governor->interrupt_driven)
> + return;
> +
> cancel_delayed_work_sync(&devfreq->work);
> }
> EXPORT_SYMBOL(devfreq_monitor_suspend);
> @@ -473,11 +483,15 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
> if (!devfreq->stop_polling)
> goto out;
>
> + if (devfreq->governor->interrupt_driven)
> + goto out_update;
> +
> if (!delayed_work_pending(&devfreq->work) &&
> devfreq->profile->polling_ms)
> queue_delayed_work(devfreq_wq, &devfreq->work,
> msecs_to_jiffies(devfreq->profile->polling_ms));
>
> +out_update:
> devfreq->last_stat_updated = jiffies;
> devfreq->stop_polling = false;
>
> @@ -509,6 +523,9 @@ void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay)
> if (devfreq->stop_polling)
> goto out;
>
> + if (devfreq->governor->interrupt_driven)
> + goto out;
> +
> /* if new delay is zero, stop polling */
> if (!new_delay) {
> mutex_unlock(&devfreq->lock);
> diff --git a/drivers/devfreq/governor.h b/drivers/devfreq/governor.h
> index bbe5ff9fcecf..dc7533ccc3db 100644
> --- a/drivers/devfreq/governor.h
> +++ b/drivers/devfreq/governor.h
> @@ -31,6 +31,8 @@
> * @name: Governor's name
> * @immutable: Immutable flag for governor. If the value is 1,
> * this govenror is never changeable to other governor.
> + * @interrupt_driven: Devfreq core won't schedule polling work for this
> + * governor if value is set to 1.
> * @get_target_freq: Returns desired operating frequency for the device.
> * Basically, get_target_freq will run
> * devfreq_dev_profile.get_dev_status() to get the
> @@ -49,6 +51,7 @@ struct devfreq_governor {
>
> const char name[DEVFREQ_NAME_LEN];
> const unsigned int immutable;
> + const unsigned int interrupt_driven;
> int (*get_target_freq)(struct devfreq *this, unsigned long *freq);
> int (*event_handler)(struct devfreq *devfreq,
> unsigned int event, void *data);
>
Reviewed-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
--
Best Regards,
Chanwoo Choi
Samsung Electronics
