Commit 5c0f6c79 authored by Dmitry Osipenko's avatar Dmitry Osipenko Committed by Chanwoo Choi
Browse files

PM / devfreq: Add new interrupt_driven flag for governors 



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: default avatarDmitry Osipenko <digetx@gmail.com>
Reviewed-by: default avatarChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: default avatarChanwoo Choi <cw00.choi@samsung.com>
parent 28615e37

drivers/devfreq/devfreq.c

+17 −0
Original line number Diff line number Diff line
@@ -410,6 +410,9 @@ 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,
@@ -427,6 +430,9 @@ 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);
@@ -454,6 +460,10 @@ 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);
@@ -474,11 +484,15 @@ 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;
@@ -510,6 +524,9 @@ 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);

drivers/devfreq/governor.h

+3 −0
Original line number Diff line number Diff line
@@ -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);

CRA Git | Maintained and supported by SUSTech CRA and CCSE