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authorDmitry Osipenko <digetx@gmail.com>2019-11-04 22:56:14 +0100
committerChanwoo Choi <cw00.choi@samsung.com>2019-11-06 04:04:01 +0100
commit5c0f6c79595760c9e366c3517314051af530e3e6 (patch)
tree47f8943363f826ff6882136883d0aa13aafe2cef /drivers/devfreq
parentPM / devfreq: tegra30: Use kHz units for dependency threshold (diff)
downloadlinux-5c0f6c79595760c9e366c3517314051af530e3e6.tar.xz
linux-5c0f6c79595760c9e366c3517314051af530e3e6.zip
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: Dmitry Osipenko <digetx@gmail.com> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Diffstat (limited to 'drivers/devfreq')
-rw-r--r--drivers/devfreq/devfreq.c17
-rw-r--r--drivers/devfreq/governor.h3
2 files changed, 20 insertions, 0 deletions
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index d6c3dce9e9d5..f840e61e5a27 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -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);
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);