Commit f198907d authored by Mykola Kostenok's avatar Mykola Kostenok Committed by Guenter Roeck
Browse files

hwmon: (aspeed-pwm-tacho) cooling device support. 



Add support in aspeed-pwm-tacho driver for cooling device creation.
This cooling device could be bound to a thermal zone
for the thermal control. Device will appear in /sys/class/thermal
folder as cooling_deviceX. Then it could be bound to particular
thermal zones. Allow specification of the cooling levels
vector - PWM duty cycle values in a range from 0 to 255
which correspond to thermal cooling states.

Signed-off-by: default avatarMykola Kostenok <c_mykolak@mellanox.com>
Reviewed-by: default avatarJoel Stanley <joel@jms.id.au>
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 5e047541

drivers/hwmon/aspeed-pwm-tacho.c

+114 −2
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
#include <linux/platform_device.h>

#include <linux/sysfs.h>

#include <linux/regmap.h>

#include <linux/thermal.h>



/* ASPEED PWM & FAN Tach Register Definition */

#define ASPEED_PTCR_CTRL		0x00
@@ -166,6 +167,18 @@ 
/* How long we sleep in us while waiting for an RPM result. */

#define ASPEED_RPM_STATUS_SLEEP_USEC	500



#define MAX_CDEV_NAME_LEN 16



struct aspeed_cooling_device {

	char name[16];

	struct aspeed_pwm_tacho_data *priv;

	struct thermal_cooling_device *tcdev;

	int pwm_port;

	u8 *cooling_levels;

	u8 max_state;

	u8 cur_state;

};



struct aspeed_pwm_tacho_data {

	struct regmap *regmap;

	unsigned long clk_freq;
@@ -180,6 +193,7 @@ struct aspeed_pwm_tacho_data { 
	u8 pwm_port_type[8];

	u8 pwm_port_fan_ctrl[8];

	u8 fan_tach_ch_source[16];

	struct aspeed_cooling_device *cdev[8];

	const struct attribute_group *groups[3];

};
@@ -765,6 +779,94 @@ static void aspeed_create_fan_tach_channel(struct aspeed_pwm_tacho_data *priv, 
	}

}



static int

aspeed_pwm_cz_get_max_state(struct thermal_cooling_device *tcdev,

			    unsigned long *state)

{

	struct aspeed_cooling_device *cdev = tcdev->devdata;



	*state = cdev->max_state;



	return 0;

}



static int

aspeed_pwm_cz_get_cur_state(struct thermal_cooling_device *tcdev,

			    unsigned long *state)

{

	struct aspeed_cooling_device *cdev = tcdev->devdata;



	*state = cdev->cur_state;



	return 0;

}



static int

aspeed_pwm_cz_set_cur_state(struct thermal_cooling_device *tcdev,

			    unsigned long state)

{

	struct aspeed_cooling_device *cdev = tcdev->devdata;



	if (state > cdev->max_state)

		return -EINVAL;



	cdev->cur_state = state;

	cdev->priv->pwm_port_fan_ctrl[cdev->pwm_port] =

					cdev->cooling_levels[cdev->cur_state];

	aspeed_set_pwm_port_fan_ctrl(cdev->priv, cdev->pwm_port,

				     cdev->cooling_levels[cdev->cur_state]);



	return 0;

}



static const struct thermal_cooling_device_ops aspeed_pwm_cool_ops = {

	.get_max_state = aspeed_pwm_cz_get_max_state,

	.get_cur_state = aspeed_pwm_cz_get_cur_state,

	.set_cur_state = aspeed_pwm_cz_set_cur_state,

};



static int aspeed_create_pwm_cooling(struct device *dev,

				     struct device_node *child,

				     struct aspeed_pwm_tacho_data *priv,

				     u32 pwm_port, u8 num_levels)

{

	int ret;

	struct aspeed_cooling_device *cdev;



	cdev = devm_kzalloc(dev, sizeof(*cdev), GFP_KERNEL);



	if (!cdev)

		return -ENOMEM;



	cdev->cooling_levels = devm_kzalloc(dev, num_levels, GFP_KERNEL);

	if (!cdev->cooling_levels)

		return -ENOMEM;



	cdev->max_state = num_levels - 1;

	ret = of_property_read_u8_array(child, "cooling-levels",

					cdev->cooling_levels,

					num_levels);

	if (ret) {

		dev_err(dev, "Property 'cooling-levels' cannot be read.\n");

		return ret;

	}

	snprintf(cdev->name, MAX_CDEV_NAME_LEN, "%s%d", child->name, pwm_port);



	cdev->tcdev = thermal_of_cooling_device_register(child,

							 cdev->name,

							 cdev,

							 &aspeed_pwm_cool_ops);

	if (IS_ERR(cdev->tcdev))

		return PTR_ERR(cdev->tcdev);



	cdev->priv = priv;

	cdev->pwm_port = pwm_port;



	priv->cdev[pwm_port] = cdev;



	return 0;

}



static int aspeed_create_fan(struct device *dev,

			     struct device_node *child,

			     struct aspeed_pwm_tacho_data *priv)
@@ -778,6 +880,15 @@ static int aspeed_create_fan(struct device *dev, 
		return ret;

	aspeed_create_pwm_port(priv, (u8)pwm_port);



	ret = of_property_count_u8_elems(child, "cooling-levels");



	if (ret > 0) {

		ret = aspeed_create_pwm_cooling(dev, child, priv, pwm_port,

						ret);

		if (ret)

			return ret;

	}



	count = of_property_count_u8_elems(child, "aspeed,fan-tach-ch");

	if (count < 1)

		return -EINVAL;
@@ -834,10 +945,11 @@ static int aspeed_pwm_tacho_probe(struct platform_device *pdev) 


	for_each_child_of_node(np, child) {

		ret = aspeed_create_fan(dev, child, priv);

		if (ret) {

			of_node_put(child);

		if (ret)

			return ret;

		}

	}



	priv->groups[0] = &pwm_dev_group;

	priv->groups[1] = &fan_dev_group;

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