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PM / devfreq: Add new interrupt_driven flag for governors

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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@gmail.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
This commit is contained in:
Dmitry Osipenko 2019-11-05 00:56:14 +03:00 committed by Chanwoo Choi
parent 28615e37be
commit 5c0f6c7959
2 changed files with 20 additions and 0 deletions
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17
drivers/devfreq/devfreq.c
View File

@ -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);

3
drivers/devfreq/governor.h
View File

@ -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);