Commit 2aee7e67 authored by Nuno Sá's avatar Nuno Sá Committed by Guenter Roeck
Browse files

hwmon: (axi-fan-control) Support temperature vs pwm points 



The HW has some predefined points where it will associate a PWM value.
However some users might want to better set these points to their
usecases. This patch exposes these points as pwm auto_points:

 * pwm1_auto_point1_temp_hyst: temperature threshold below which PWM should
   be 0%;
 * pwm1_auto_point1_temp: temperature threshold above which PWM should be
   25%;
 * pwm1_auto_point2_temp_hyst: temperature threshold below which PWM should
   be 25%;
 * pwm1_auto_point2_temp: temperature threshold above which PWM should be
   50%;
 * pwm1_auto_point3_temp_hyst: temperature threshold below which PWM should
   be 50%;
 * pwm1_auto_point3_temp: temperature threshold above which PWM should be
   75%;
 * pwm1_auto_point4_temp_hyst: temperature threshold below which PWM should
   be 75%;
 * pwm1_auto_point4_temp: temperature threshold above which PWM should be
   100%;

Signed-off-by: default avatarNuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20210811114853.159298-4-nuno.sa@analog.com


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent e66705de

drivers/hwmon/axi-fan-control.c

+73 −1
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
#include <linux/clk.h>

#include <linux/fpga/adi-axi-common.h>

#include <linux/hwmon.h>

#include <linux/hwmon-sysfs.h>

#include <linux/interrupt.h>

#include <linux/io.h>

#include <linux/kernel.h>
@@ -23,6 +24,14 @@ 
#define ADI_REG_PWM_PERIOD	0x00c0

#define ADI_REG_TACH_MEASUR	0x00c4

#define ADI_REG_TEMPERATURE	0x00c8

#define ADI_REG_TEMP_00_H	0x0100

#define ADI_REG_TEMP_25_L	0x0104

#define ADI_REG_TEMP_25_H	0x0108

#define ADI_REG_TEMP_50_L	0x010c

#define ADI_REG_TEMP_50_H	0x0110

#define ADI_REG_TEMP_75_L	0x0114

#define ADI_REG_TEMP_75_H	0x0118

#define ADI_REG_TEMP_100_L	0x011c



#define ADI_REG_IRQ_MASK	0x0040

#define ADI_REG_IRQ_PENDING	0x0044
@@ -62,6 +71,39 @@ static inline u32 axi_ioread(const u32 reg, 
	return ioread32(ctl->base + reg);

}



/*

 * The core calculates the temperature as:

 *	T = /raw * 509.3140064 / 65535) - 280.2308787

 */

static ssize_t axi_fan_control_show(struct device *dev, struct device_attribute *da, char *buf)

{

	struct axi_fan_control_data *ctl = dev_get_drvdata(dev);

	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);

	u32 temp = axi_ioread(attr->index, ctl);



	temp = DIV_ROUND_CLOSEST_ULL(temp * 509314ULL, 65535) - 280230;



	return sprintf(buf, "%u\n", temp);

}



static ssize_t axi_fan_control_store(struct device *dev, struct device_attribute *da,

				     const char *buf, size_t count)

{

	struct axi_fan_control_data *ctl = dev_get_drvdata(dev);

	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);

	u32 temp;

	int ret;



	ret = kstrtou32(buf, 10, &temp);

	if (ret)

		return ret;



	temp = DIV_ROUND_CLOSEST_ULL((temp + 280230) * 65535ULL, 509314);

	axi_iowrite(temp, attr->index, ctl);



	return count;

}



static long axi_fan_control_get_pwm_duty(const struct axi_fan_control_data *ctl)

{

	u32 pwm_width = axi_ioread(ADI_REG_PWM_WIDTH, ctl);
@@ -375,6 +417,36 @@ static const struct hwmon_chip_info axi_chip_info = { 
	.info = axi_fan_control_info,

};



/* temperature threshold below which PWM should be 0% */

static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point1_temp_hyst, axi_fan_control, ADI_REG_TEMP_00_H);

/* temperature threshold above which PWM should be 25% */

static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point1_temp, axi_fan_control, ADI_REG_TEMP_25_L);

/* temperature threshold below which PWM should be 25% */

static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_temp_hyst, axi_fan_control, ADI_REG_TEMP_25_H);

/* temperature threshold above which PWM should be 50% */

static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_temp, axi_fan_control, ADI_REG_TEMP_50_L);

/* temperature threshold below which PWM should be 50% */

static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point3_temp_hyst, axi_fan_control, ADI_REG_TEMP_50_H);

/* temperature threshold above which PWM should be 75% */

static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point3_temp, axi_fan_control, ADI_REG_TEMP_75_L);

/* temperature threshold below which PWM should be 75% */

static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point4_temp_hyst, axi_fan_control, ADI_REG_TEMP_75_H);

/* temperature threshold above which PWM should be 100% */

static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point4_temp, axi_fan_control, ADI_REG_TEMP_100_L);



static struct attribute *axi_fan_control_attrs[] = {

	&sensor_dev_attr_pwm1_auto_point1_temp_hyst.dev_attr.attr,

	&sensor_dev_attr_pwm1_auto_point1_temp.dev_attr.attr,

	&sensor_dev_attr_pwm1_auto_point2_temp_hyst.dev_attr.attr,

	&sensor_dev_attr_pwm1_auto_point2_temp.dev_attr.attr,

	&sensor_dev_attr_pwm1_auto_point3_temp_hyst.dev_attr.attr,

	&sensor_dev_attr_pwm1_auto_point3_temp.dev_attr.attr,

	&sensor_dev_attr_pwm1_auto_point4_temp_hyst.dev_attr.attr,

	&sensor_dev_attr_pwm1_auto_point4_temp.dev_attr.attr,

	NULL,

};

ATTRIBUTE_GROUPS(axi_fan_control);



static const u32 version_1_0_0 = ADI_AXI_PCORE_VER(1, 0, 'a');



static const struct of_device_id axi_fan_control_of_match[] = {
@@ -459,7 +531,7 @@ static int axi_fan_control_probe(struct platform_device *pdev) 
							 name,

							 ctl,

							 &axi_chip_info,

							 NULL);

							 axi_fan_control_groups);



	return PTR_ERR_OR_ZERO(ctl->hdev);

}