From 5c0f6c79595760c9e366c3517314051af530e3e6 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Tue, 5 Nov 2019 00:56:14 +0300 Subject: 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 Reviewed-by: Chanwoo Choi Signed-off-by: Chanwoo Choi --- drivers/devfreq/devfreq.c | 17 +++++++++++++++++ drivers/devfreq/governor.h | 3 +++ 2 files changed, 20 insertions(+) (limited to 'drivers/devfreq') 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); -- cgit