Commit 2c3b0463 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

Merge branch 'for-next' of https://git.kernel.org/pub/scm/linux/kernel/git/mzx/devfreq 

Pull devfreq framework changes for v4.21 from MyungJoo Ham:

"This includes the suspend-frequency support for devfreq, which is
 similar with suspend_freq in cpufreq."

* 'for-next' of https://git.kernel.org/pub/scm/linux/kernel/git/mzx/devfreq:
  PM / devfreq: add devfreq_suspend/resume() functions
  PM / devfreq: add support for suspend/resume of a devfreq device
  PM / devfreq: refactor set_target frequency function
parents 40e020c1 59031956

drivers/devfreq/devfreq.c

+121 −32
Original line number Diff line number Diff line
@@ -285,6 +285,44 @@ static int devfreq_notify_transition(struct devfreq *devfreq, 
	return 0;

}



static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq,

			      u32 flags)

{

	struct devfreq_freqs freqs;

	unsigned long cur_freq;

	int err = 0;



	if (devfreq->profile->get_cur_freq)

		devfreq->profile->get_cur_freq(devfreq->dev.parent, &cur_freq);

	else

		cur_freq = devfreq->previous_freq;



	freqs.old = cur_freq;

	freqs.new = new_freq;

	devfreq_notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE);



	err = devfreq->profile->target(devfreq->dev.parent, &new_freq, flags);

	if (err) {

		freqs.new = cur_freq;

		devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE);

		return err;

	}



	freqs.new = new_freq;

	devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE);



	if (devfreq_update_status(devfreq, new_freq))

		dev_err(&devfreq->dev,

			"Couldn't update frequency transition information.\n");



	devfreq->previous_freq = new_freq;



	if (devfreq->suspend_freq)

		devfreq->resume_freq = cur_freq;



	return err;

}



/* Load monitoring helper functions for governors use */



/**
@@ -296,8 +334,7 @@ static int devfreq_notify_transition(struct devfreq *devfreq, 
 */

int update_devfreq(struct devfreq *devfreq)

{

	struct devfreq_freqs freqs;

	unsigned long freq, cur_freq, min_freq, max_freq;

	unsigned long freq, min_freq, max_freq;

	int err = 0;

	u32 flags = 0;
@@ -333,31 +370,8 @@ int update_devfreq(struct devfreq *devfreq) 
		flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */

	}



	if (devfreq->profile->get_cur_freq)

		devfreq->profile->get_cur_freq(devfreq->dev.parent, &cur_freq);

	else

		cur_freq = devfreq->previous_freq;



	freqs.old = cur_freq;

	freqs.new = freq;

	devfreq_notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE);

	return devfreq_set_target(devfreq, freq, flags);



	err = devfreq->profile->target(devfreq->dev.parent, &freq, flags);

	if (err) {

		freqs.new = cur_freq;

		devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE);

		return err;

	}



	freqs.new = freq;

	devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE);



	if (devfreq_update_status(devfreq, freq))

		dev_err(&devfreq->dev,

			"Couldn't update frequency transition information.\n");



	devfreq->previous_freq = freq;

	return err;

}

EXPORT_SYMBOL(update_devfreq);
@@ -657,6 +671,9 @@ struct devfreq *devfreq_add_device(struct device *dev, 
	}

	devfreq->max_freq = devfreq->scaling_max_freq;



	devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev);

	atomic_set(&devfreq->suspend_count, 0);



	dev_set_name(&devfreq->dev, "devfreq%d",

				atomic_inc_return(&devfreq_no));

	err = device_register(&devfreq->dev);
@@ -857,14 +874,28 @@ EXPORT_SYMBOL(devm_devfreq_remove_device); 
 */

int devfreq_suspend_device(struct devfreq *devfreq)

{

	int ret;



	if (!devfreq)

		return -EINVAL;



	if (!devfreq->governor)

	if (atomic_inc_return(&devfreq->suspend_count) > 1)

		return 0;



	return devfreq->governor->event_handler(devfreq,

	if (devfreq->governor) {

		ret = devfreq->governor->event_handler(devfreq,

					DEVFREQ_GOV_SUSPEND, NULL);

		if (ret)

			return ret;

	}



	if (devfreq->suspend_freq) {

		ret = devfreq_set_target(devfreq, devfreq->suspend_freq, 0);

		if (ret)

			return ret;

	}



	return 0;

}

EXPORT_SYMBOL(devfreq_suspend_device);
@@ -878,17 +909,75 @@ EXPORT_SYMBOL(devfreq_suspend_device); 
 */

int devfreq_resume_device(struct devfreq *devfreq)

{

	int ret;



	if (!devfreq)

		return -EINVAL;



	if (!devfreq->governor)

	if (atomic_dec_return(&devfreq->suspend_count) >= 1)

		return 0;



	return devfreq->governor->event_handler(devfreq,

	if (devfreq->resume_freq) {

		ret = devfreq_set_target(devfreq, devfreq->resume_freq, 0);

		if (ret)

			return ret;

	}



	if (devfreq->governor) {

		ret = devfreq->governor->event_handler(devfreq,

					DEVFREQ_GOV_RESUME, NULL);

		if (ret)

			return ret;

	}



	return 0;

}

EXPORT_SYMBOL(devfreq_resume_device);



/**

 * devfreq_suspend() - Suspend devfreq governors and devices

 *

 * Called during system wide Suspend/Hibernate cycles for suspending governors

 * and devices preserving the state for resume. On some platforms the devfreq

 * device must have precise state (frequency) after resume in order to provide

 * fully operating setup.

 */

void devfreq_suspend(void)

{

	struct devfreq *devfreq;

	int ret;



	mutex_lock(&devfreq_list_lock);

	list_for_each_entry(devfreq, &devfreq_list, node) {

		ret = devfreq_suspend_device(devfreq);

		if (ret)

			dev_err(&devfreq->dev,

				"failed to suspend devfreq device\n");

	}

	mutex_unlock(&devfreq_list_lock);

}



/**

 * devfreq_resume() - Resume devfreq governors and devices

 *

 * Called during system wide Suspend/Hibernate cycle for resuming governors and

 * devices that are suspended with devfreq_suspend().

 */

void devfreq_resume(void)

{

	struct devfreq *devfreq;

	int ret;



	mutex_lock(&devfreq_list_lock);

	list_for_each_entry(devfreq, &devfreq_list, node) {

		ret = devfreq_resume_device(devfreq);

		if (ret)

			dev_warn(&devfreq->dev,

				 "failed to resume devfreq device\n");

	}

	mutex_unlock(&devfreq_list_lock);

}



/**

 * devfreq_add_governor() - Add devfreq governor

 * @governor:	the devfreq governor to be added

include/linux/devfreq.h

+13 −0
Original line number Diff line number Diff line
@@ -131,6 +131,9 @@ struct devfreq_dev_profile { 
 * @scaling_min_freq:	Limit minimum frequency requested by OPP interface

 * @scaling_max_freq:	Limit maximum frequency requested by OPP interface

 * @stop_polling:	 devfreq polling status of a device.

 * @suspend_freq:	 frequency of a device set during suspend phase.

 * @resume_freq:	 frequency of a device set in resume phase.

 * @suspend_count:	 suspend requests counter for a device.

 * @total_trans:	Number of devfreq transitions

 * @trans_table:	Statistics of devfreq transitions

 * @time_in_state:	Statistics of devfreq states
@@ -167,6 +170,10 @@ struct devfreq { 
	unsigned long scaling_max_freq;

	bool stop_polling;



	unsigned long suspend_freq;

	unsigned long resume_freq;

	atomic_t suspend_count;



	/* information for device frequency transition */

	unsigned int total_trans;

	unsigned int *trans_table;
@@ -198,6 +205,9 @@ extern void devm_devfreq_remove_device(struct device *dev, 
extern int devfreq_suspend_device(struct devfreq *devfreq);

extern int devfreq_resume_device(struct devfreq *devfreq);



extern void devfreq_suspend(void);

extern void devfreq_resume(void);



/**

 * update_devfreq() - Reevaluate the device and configure frequency

 * @devfreq:	the devfreq device
@@ -324,6 +334,9 @@ static inline int devfreq_resume_device(struct devfreq *devfreq) 
	return 0;

}



static inline void devfreq_suspend(void) {}

static inline void devfreq_resume(void) {}



static inline struct dev_pm_opp *devfreq_recommended_opp(struct device *dev,

					   unsigned long *freq, u32 flags)

{

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