Commit 1224451b authored by Daniel Lezcano's avatar Daniel Lezcano Committed by Chanwoo Choi
Browse files

PM / devfreq: Register devfreq as a cooling device on demand 



Currently the default behavior is to manually having the devfreq
backend to register themselves as a devfreq cooling device.

Instead of adding the code in the drivers for the thermal cooling
device registering, let's provide a flag in the devfreq's profile to
tell the common devfreq code to register the newly created devfreq as
a cooling device.

Suggested-by: default avatarChanwoo Choi <cwchoi00@gmail.com>
Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: default avatarSteven Price <steven.price@arm.com>
Reviewed-by: default avatarLukasz Luba <lukasz.luba@arm.com>
Signed-off-by: default avatarChanwoo Choi <cw00.choi@samsung.com>
parent fe07bfda

drivers/devfreq/devfreq.c

+9 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#include <linux/kmod.h>

#include <linux/sched.h>

#include <linux/debugfs.h>

#include <linux/devfreq_cooling.h>

#include <linux/errno.h>

#include <linux/err.h>

#include <linux/init.h>
@@ -935,6 +936,12 @@ struct devfreq *devfreq_add_device(struct device *dev, 


	mutex_unlock(&devfreq_list_lock);



	if (devfreq->profile->is_cooling_device) {

		devfreq->cdev = devfreq_cooling_em_register(devfreq, NULL);

		if (IS_ERR(devfreq->cdev))

			devfreq->cdev = NULL;

	}



	return devfreq;



err_init:
@@ -960,6 +967,8 @@ int devfreq_remove_device(struct devfreq *devfreq) 
	if (!devfreq)

		return -EINVAL;



	devfreq_cooling_unregister(devfreq->cdev);



	if (devfreq->governor) {

		devfreq->governor->event_handler(devfreq,

						 DEVFREQ_GOV_STOP, NULL);

include/linux/devfreq.h

+9 −0
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ enum devfreq_timer { 


struct devfreq;

struct devfreq_governor;

struct thermal_cooling_device;



/**

 * struct devfreq_dev_status - Data given from devfreq user device to
@@ -98,11 +99,15 @@ struct devfreq_dev_status { 
 * @freq_table:		Optional list of frequencies to support statistics

 *			and freq_table must be generated in ascending order.

 * @max_state:		The size of freq_table.

 *

 * @is_cooling_device: A self-explanatory boolean giving the device a

 *                     cooling effect property.

 */

struct devfreq_dev_profile {

	unsigned long initial_freq;

	unsigned int polling_ms;

	enum devfreq_timer timer;

	bool is_cooling_device;



	int (*target)(struct device *dev, unsigned long *freq, u32 flags);

	int (*get_dev_status)(struct device *dev,
@@ -156,6 +161,7 @@ struct devfreq_stats { 
 * @suspend_count:	 suspend requests counter for a device.

 * @stats:	Statistics of devfreq device behavior

 * @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier

 * @cdev:	Cooling device pointer if the devfreq has cooling property

 * @nb_min:		Notifier block for DEV_PM_QOS_MIN_FREQUENCY

 * @nb_max:		Notifier block for DEV_PM_QOS_MAX_FREQUENCY

 *
@@ -198,6 +204,9 @@ struct devfreq { 


	struct srcu_notifier_head transition_notifier_list;



	/* Pointer to the cooling device if used for thermal mitigation */

	struct thermal_cooling_device *cdev;



	struct notifier_block nb_min;

	struct notifier_block nb_max;

};