Commit 8f05bcc3 authored by Chris Packham's avatar Chris Packham Committed by Guenter Roeck
Browse files

hwmon: (adt7475) temperature smoothing 



When enabled temperature smoothing allows ramping the fan speed over a
configurable period of time instead of jumping to the new speed
instantaneously.

Signed-off-by: default avatarChris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 3490c92a

Documentation/hwmon/adt7475

+4 −0
Original line number Diff line number Diff line
@@ -114,6 +114,10 @@ minimum (i.e. auto_point1_pwm). This behaviour can be configured using the 
pwm[1-*]_stall_disable sysfs attribute. A value of 0 means the fans will shut

off. A value of 1 means the fans will run at auto_point1_pwm.



The responsiveness of the ADT747x to temperature changes can be configured.

This allows smoothing of the fan speed transition. To set the transition time

set the value in ms in the temp[1-*]_smoothing sysfs attribute.



Notes

-----

drivers/hwmon/adt7475.c

+91 −0
Original line number Diff line number Diff line
@@ -526,6 +526,88 @@ static ssize_t set_temp(struct device *dev, struct device_attribute *attr, 
	return count;

}



/* Assuming CONFIG6[SLOW] is 0 */

static const int ad7475_st_map[] = {

	37500, 18800, 12500, 7500, 4700, 3100, 1600, 800,

};



static ssize_t show_temp_st(struct device *dev, struct device_attribute *attr,

				  char *buf)

{

	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);

	struct i2c_client *client = to_i2c_client(dev);

	struct adt7475_data *data = i2c_get_clientdata(client);

	long val;



	switch (sattr->index) {

	case 0:

		val = data->enh_acoustics[0] & 0xf;

		break;

	case 1:

		val = (data->enh_acoustics[1] >> 4) & 0xf;

		break;

	case 2:

	default:

		val = data->enh_acoustics[1] & 0xf;

		break;

	}



	if (val & 0x8)

		return sprintf(buf, "%d\n", ad7475_st_map[val & 0x7]);

	else

		return sprintf(buf, "0\n");

}



static ssize_t set_temp_st(struct device *dev, struct device_attribute *attr,

				 const char *buf, size_t count)

{

	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);

	struct i2c_client *client = to_i2c_client(dev);

	struct adt7475_data *data = i2c_get_clientdata(client);

	unsigned char reg;

	int shift, idx;

	ulong val;



	if (kstrtoul(buf, 10, &val))

		return -EINVAL;



	switch (sattr->index) {

	case 0:

		reg = REG_ENHANCE_ACOUSTICS1;

		shift = 0;

		idx = 0;

		break;

	case 1:

		reg = REG_ENHANCE_ACOUSTICS2;

		shift = 0;

		idx = 1;

		break;

	case 2:

	default:

		reg = REG_ENHANCE_ACOUSTICS2;

		shift = 4;

		idx = 1;

		break;

	}



	if (val > 0) {

		val = find_closest_descending(val, ad7475_st_map,

					      ARRAY_SIZE(ad7475_st_map));

		val |= 0x8;

	}



	mutex_lock(&data->lock);



	data->enh_acoustics[idx] &= ~(0xf << shift);

	data->enh_acoustics[idx] |= (val << shift);



	i2c_smbus_write_byte_data(client, reg, data->enh_acoustics[idx]);



	mutex_unlock(&data->lock);



	return count;

}



/*

 * Table of autorange values - the user will write the value in millidegrees,

 * and we'll convert it
@@ -1009,6 +1091,8 @@ static SENSOR_DEVICE_ATTR_2(temp1_crit, S_IRUGO | S_IWUSR, show_temp, set_temp, 
			    THERM, 0);

static SENSOR_DEVICE_ATTR_2(temp1_crit_hyst, S_IRUGO | S_IWUSR, show_temp,

			    set_temp, HYSTERSIS, 0);

static SENSOR_DEVICE_ATTR_2(temp1_smoothing, S_IRUGO | S_IWUSR, show_temp_st,

			    set_temp_st, 0, 0);

static SENSOR_DEVICE_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, INPUT, 1);

static SENSOR_DEVICE_ATTR_2(temp2_alarm, S_IRUGO, show_temp, NULL, ALARM, 1);

static SENSOR_DEVICE_ATTR_2(temp2_max, S_IRUGO | S_IWUSR, show_temp, set_temp,
@@ -1025,6 +1109,8 @@ static SENSOR_DEVICE_ATTR_2(temp2_crit, S_IRUGO | S_IWUSR, show_temp, set_temp, 
			    THERM, 1);

static SENSOR_DEVICE_ATTR_2(temp2_crit_hyst, S_IRUGO | S_IWUSR, show_temp,

			    set_temp, HYSTERSIS, 1);

static SENSOR_DEVICE_ATTR_2(temp2_smoothing, S_IRUGO | S_IWUSR, show_temp_st,

			    set_temp_st, 0, 1);

static SENSOR_DEVICE_ATTR_2(temp3_input, S_IRUGO, show_temp, NULL, INPUT, 2);

static SENSOR_DEVICE_ATTR_2(temp3_alarm, S_IRUGO, show_temp, NULL, ALARM, 2);

static SENSOR_DEVICE_ATTR_2(temp3_fault, S_IRUGO, show_temp, NULL, FAULT, 2);
@@ -1042,6 +1128,8 @@ static SENSOR_DEVICE_ATTR_2(temp3_crit, S_IRUGO | S_IWUSR, show_temp, set_temp, 
			    THERM, 2);

static SENSOR_DEVICE_ATTR_2(temp3_crit_hyst, S_IRUGO | S_IWUSR, show_temp,

			    set_temp, HYSTERSIS, 2);

static SENSOR_DEVICE_ATTR_2(temp3_smoothing, S_IRUGO | S_IWUSR, show_temp_st,

			    set_temp_st, 0, 2);

static SENSOR_DEVICE_ATTR_2(fan1_input, S_IRUGO, show_tach, NULL, INPUT, 0);

static SENSOR_DEVICE_ATTR_2(fan1_min, S_IRUGO | S_IWUSR, show_tach, set_tach,

			    MIN, 0);
@@ -1126,6 +1214,7 @@ static struct attribute *adt7475_attrs[] = { 
	&sensor_dev_attr_temp1_auto_point2_temp.dev_attr.attr,

	&sensor_dev_attr_temp1_crit.dev_attr.attr,

	&sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,

	&sensor_dev_attr_temp1_smoothing.dev_attr.attr,

	&sensor_dev_attr_temp2_input.dev_attr.attr,

	&sensor_dev_attr_temp2_alarm.dev_attr.attr,

	&sensor_dev_attr_temp2_max.dev_attr.attr,
@@ -1135,6 +1224,7 @@ static struct attribute *adt7475_attrs[] = { 
	&sensor_dev_attr_temp2_auto_point2_temp.dev_attr.attr,

	&sensor_dev_attr_temp2_crit.dev_attr.attr,

	&sensor_dev_attr_temp2_crit_hyst.dev_attr.attr,

	&sensor_dev_attr_temp2_smoothing.dev_attr.attr,

	&sensor_dev_attr_temp3_input.dev_attr.attr,

	&sensor_dev_attr_temp3_fault.dev_attr.attr,

	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
@@ -1145,6 +1235,7 @@ static struct attribute *adt7475_attrs[] = { 
	&sensor_dev_attr_temp3_auto_point2_temp.dev_attr.attr,

	&sensor_dev_attr_temp3_crit.dev_attr.attr,

	&sensor_dev_attr_temp3_crit_hyst.dev_attr.attr,

	&sensor_dev_attr_temp3_smoothing.dev_attr.attr,

	&sensor_dev_attr_fan1_input.dev_attr.attr,

	&sensor_dev_attr_fan1_min.dev_attr.attr,

	&sensor_dev_attr_fan1_alarm.dev_attr.attr,