Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 9f38271c authored by Javi Merino's avatar Javi Merino Committed by Eduardo Valentin
Browse files

thermal: export thermal_zone_parameters to sysfs 



It's useful for tuning to be able to edit thermal_zone_parameters from
userspace.  Export them to the thermal_zone sysfs so that they can be
easily changed.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: default avatarJavi Merino <javi.merino@arm.com>
Signed-off-by: default avatarEduardo Valentin <edubezval@gmail.com>
parent 0cdf97e1

Documentation/thermal/sysfs-api.txt

+52 −0
Original line number Diff line number Diff line
@@ -184,6 +184,12 @@ Thermal zone device sys I/F, created once it's registered: 
    |---trip_point_[0-*]_type:	Trip point type

    |---trip_point_[0-*]_hyst:	Hysteresis value for this trip point

    |---emul_temp:		Emulated temperature set node

    |---sustainable_power:      Sustainable dissipatable power

    |---k_po:                   Proportional term during temperature overshoot

    |---k_pu:                   Proportional term during temperature undershoot

    |---k_i:                    PID's integral term in the power allocator gov

    |---k_d:                    PID's derivative term in the power allocator

    |---integral_cutoff:        Offset above which errors are accumulated



Thermal cooling device sys I/F, created once it's registered:

/sys/class/thermal/cooling_device[0-*]:
@@ -307,6 +313,52 @@ emul_temp 
	  because userland can easily disable the thermal policy by simply

	  flooding this sysfs node with low temperature values.



sustainable_power

	An estimate of the sustained power that can be dissipated by

	the thermal zone. Used by the power allocator governor. For

	more information see Documentation/thermal/power_allocator.txt

	Unit: milliwatts

	RW, Optional



k_po

	The proportional term of the power allocator governor's PID

	controller during temperature overshoot. Temperature overshoot

	is when the current temperature is above the "desired

	temperature" trip point. For more information see

	Documentation/thermal/power_allocator.txt

	RW, Optional



k_pu

	The proportional term of the power allocator governor's PID

	controller during temperature undershoot. Temperature undershoot

	is when the current temperature is below the "desired

	temperature" trip point. For more information see

	Documentation/thermal/power_allocator.txt

	RW, Optional



k_i

	The integral term of the power allocator governor's PID

	controller. This term allows the PID controller to compensate

	for long term drift. For more information see

	Documentation/thermal/power_allocator.txt

	RW, Optional



k_d

	The derivative term of the power allocator governor's PID

	controller. For more information see

	Documentation/thermal/power_allocator.txt

	RW, Optional



integral_cutoff

	Temperature offset from the desired temperature trip point

	above which the integral term of the power allocator

	governor's PID controller starts accumulating errors. For

	example, if integral_cutoff is 0, then the integral term only

	accumulates error when temperature is above the desired

	temperature trip point. For more information see

	Documentation/thermal/power_allocator.txt

	RW, Optional



*****************************

* Cooling device attributes *

*****************************

drivers/thermal/thermal_core.c

+101 −0
Original line number Diff line number Diff line
@@ -875,6 +875,102 @@ emul_temp_store(struct device *dev, struct device_attribute *attr, 
static DEVICE_ATTR(emul_temp, S_IWUSR, NULL, emul_temp_store);

#endif/*CONFIG_THERMAL_EMULATION*/



static ssize_t

sustainable_power_show(struct device *dev, struct device_attribute *devattr,

		       char *buf)

{

	struct thermal_zone_device *tz = to_thermal_zone(dev);



	if (tz->tzp)

		return sprintf(buf, "%u\n", tz->tzp->sustainable_power);

	else

		return -EIO;

}



static ssize_t

sustainable_power_store(struct device *dev, struct device_attribute *devattr,

			const char *buf, size_t count)

{

	struct thermal_zone_device *tz = to_thermal_zone(dev);

	u32 sustainable_power;



	if (!tz->tzp)

		return -EIO;



	if (kstrtou32(buf, 10, &sustainable_power))

		return -EINVAL;



	tz->tzp->sustainable_power = sustainable_power;



	return count;

}

static DEVICE_ATTR(sustainable_power, S_IWUSR | S_IRUGO, sustainable_power_show,

		sustainable_power_store);



#define create_s32_tzp_attr(name)					\

	static ssize_t							\

	name##_show(struct device *dev, struct device_attribute *devattr, \

		char *buf)						\

	{								\

	struct thermal_zone_device *tz = to_thermal_zone(dev);		\

									\

	if (tz->tzp)							\

		return sprintf(buf, "%u\n", tz->tzp->name);		\

	else								\

		return -EIO;						\

	}								\

									\

	static ssize_t							\

	name##_store(struct device *dev, struct device_attribute *devattr, \

		const char *buf, size_t count)				\

	{								\

		struct thermal_zone_device *tz = to_thermal_zone(dev);	\

		s32 value;						\

									\

		if (!tz->tzp)						\

			return -EIO;					\

									\

		if (kstrtos32(buf, 10, &value))				\

			return -EINVAL;					\

									\

		tz->tzp->name = value;					\

									\

		return count;						\

	}								\

	static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, name##_show, name##_store)



create_s32_tzp_attr(k_po);

create_s32_tzp_attr(k_pu);

create_s32_tzp_attr(k_i);

create_s32_tzp_attr(k_d);

create_s32_tzp_attr(integral_cutoff);

#undef create_s32_tzp_attr



static struct device_attribute *dev_tzp_attrs[] = {

	&dev_attr_sustainable_power,

	&dev_attr_k_po,

	&dev_attr_k_pu,

	&dev_attr_k_i,

	&dev_attr_k_d,

	&dev_attr_integral_cutoff,

};



static int create_tzp_attrs(struct device *dev)

{

	int i;



	for (i = 0; i < ARRAY_SIZE(dev_tzp_attrs); i++) {

		int ret;

		struct device_attribute *dev_attr = dev_tzp_attrs[i];



		ret = device_create_file(dev, dev_attr);

		if (ret)

			return ret;

	}



	return 0;

}



/**

 * power_actor_get_max_power() - get the maximum power that a cdev can consume

 * @cdev:	pointer to &thermal_cooling_device
@@ -1712,6 +1808,11 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type, 
	if (result)

		goto unregister;



	/* Add thermal zone params */

	result = create_tzp_attrs(&tz->device);

	if (result)

		goto unregister;



	/* Update 'this' zone's governor information */

	mutex_lock(&thermal_governor_lock);