hwmon: (adt7475) fan stall prevention

By default adt7475 will stop the fans (pwm duty cycle 0%) when the
temperature drops past Tmin - hysteresis. Some systems want to keep the
fans moving even when the temperature drops so add new sysfs attributes
that configure the enhanced acoustics min 1-3 which allows the fans to
run at the minimum configure pwm duty cycle.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Chris Packham 2017-05-15 13:30:27 +12:00 committed by Guenter Roeck
parent e465164040
commit 1d58f5efbf
2 changed files with 55 additions and 0 deletions

View File

@ -109,6 +109,11 @@ fan speed) is applied. PWM values range from 0 (off) to 255 (full speed).
Fan speed may be set to maximum when the temperature sensor associated with
the PWM control exceeds temp#_max.
At Tmin - hysteresis the PWM output can either be off (0% duty cycle) or at the
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.
Notes
-----

View File

@ -79,6 +79,9 @@
#define REG_TEMP_TRANGE_BASE 0x5F
#define REG_ENHANCE_ACOUSTICS1 0x62
#define REG_ENHANCE_ACOUSTICS2 0x63
#define REG_PWM_MIN_BASE 0x64
#define REG_TEMP_TMIN_BASE 0x67
@ -209,6 +212,7 @@ struct adt7475_data {
u8 range[3];
u8 pwmctl[3];
u8 pwmchan[3];
u8 enh_acoustics[2];
u8 vid;
u8 vrm;
@ -700,6 +704,43 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *attr,
data->pwm[sattr->nr][sattr->index] = clamp_val(val, 0, 0xFF);
i2c_smbus_write_byte_data(client, reg,
data->pwm[sattr->nr][sattr->index]);
mutex_unlock(&data->lock);
return count;
}
static ssize_t show_stall_disable(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);
u8 mask = BIT(5 + sattr->index);
return sprintf(buf, "%d\n", !!(data->enh_acoustics[0] & mask));
}
static ssize_t set_stall_disable(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);
long val;
u8 mask = BIT(5 + sattr->index);
if (kstrtol(buf, 10, &val))
return -EINVAL;
mutex_lock(&data->lock);
data->enh_acoustics[0] &= ~mask;
if (val)
data->enh_acoustics[0] |= mask;
i2c_smbus_write_byte_data(client, REG_ENHANCE_ACOUSTICS1,
data->enh_acoustics[0]);
mutex_unlock(&data->lock);
@ -1028,6 +1069,8 @@ static SENSOR_DEVICE_ATTR_2(pwm1_auto_point1_pwm, S_IRUGO | S_IWUSR, show_pwm,
set_pwm, MIN, 0);
static SENSOR_DEVICE_ATTR_2(pwm1_auto_point2_pwm, S_IRUGO | S_IWUSR, show_pwm,
set_pwm, MAX, 0);
static SENSOR_DEVICE_ATTR_2(pwm1_stall_disable, S_IRUGO | S_IWUSR,
show_stall_disable, set_stall_disable, 0, 0);
static SENSOR_DEVICE_ATTR_2(pwm2, S_IRUGO | S_IWUSR, show_pwm, set_pwm, INPUT,
1);
static SENSOR_DEVICE_ATTR_2(pwm2_freq, S_IRUGO | S_IWUSR, show_pwmfreq,
@ -1040,6 +1083,8 @@ static SENSOR_DEVICE_ATTR_2(pwm2_auto_point1_pwm, S_IRUGO | S_IWUSR, show_pwm,
set_pwm, MIN, 1);
static SENSOR_DEVICE_ATTR_2(pwm2_auto_point2_pwm, S_IRUGO | S_IWUSR, show_pwm,
set_pwm, MAX, 1);
static SENSOR_DEVICE_ATTR_2(pwm2_stall_disable, S_IRUGO | S_IWUSR,
show_stall_disable, set_stall_disable, 0, 1);
static SENSOR_DEVICE_ATTR_2(pwm3, S_IRUGO | S_IWUSR, show_pwm, set_pwm, INPUT,
2);
static SENSOR_DEVICE_ATTR_2(pwm3_freq, S_IRUGO | S_IWUSR, show_pwmfreq,
@ -1052,6 +1097,8 @@ static SENSOR_DEVICE_ATTR_2(pwm3_auto_point1_pwm, S_IRUGO | S_IWUSR, show_pwm,
set_pwm, MIN, 2);
static SENSOR_DEVICE_ATTR_2(pwm3_auto_point2_pwm, S_IRUGO | S_IWUSR, show_pwm,
set_pwm, MAX, 2);
static SENSOR_DEVICE_ATTR_2(pwm3_stall_disable, S_IRUGO | S_IWUSR,
show_stall_disable, set_stall_disable, 0, 2);
/* Non-standard name, might need revisiting */
static DEVICE_ATTR_RW(pwm_use_point2_pwm_at_crit);
@ -1112,12 +1159,14 @@ static struct attribute *adt7475_attrs[] = {
&sensor_dev_attr_pwm1_auto_channels_temp.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
&sensor_dev_attr_pwm1_stall_disable.dev_attr.attr,
&sensor_dev_attr_pwm3.dev_attr.attr,
&sensor_dev_attr_pwm3_freq.dev_attr.attr,
&sensor_dev_attr_pwm3_enable.dev_attr.attr,
&sensor_dev_attr_pwm3_auto_channels_temp.dev_attr.attr,
&sensor_dev_attr_pwm3_auto_point1_pwm.dev_attr.attr,
&sensor_dev_attr_pwm3_auto_point2_pwm.dev_attr.attr,
&sensor_dev_attr_pwm3_stall_disable.dev_attr.attr,
&dev_attr_pwm_use_point2_pwm_at_crit.attr,
NULL,
};
@ -1136,6 +1185,7 @@ static struct attribute *pwm2_attrs[] = {
&sensor_dev_attr_pwm2_auto_channels_temp.dev_attr.attr,
&sensor_dev_attr_pwm2_auto_point1_pwm.dev_attr.attr,
&sensor_dev_attr_pwm2_auto_point2_pwm.dev_attr.attr,
&sensor_dev_attr_pwm2_stall_disable.dev_attr.attr,
NULL
};