From 1d58f5efbf2d8599a9062e4c800a072e2f015625 Mon Sep 17 00:00:00 2001 From: Chris Packham Date: Mon, 15 May 2017 13:30:27 +1200 Subject: [PATCH] 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 Signed-off-by: Guenter Roeck --- Documentation/hwmon/adt7475 | 5 ++++ drivers/hwmon/adt7475.c | 50 +++++++++++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+) diff --git a/Documentation/hwmon/adt7475 b/Documentation/hwmon/adt7475 index 0502f2b464e1..dc0b55794c47 100644 --- a/Documentation/hwmon/adt7475 +++ b/Documentation/hwmon/adt7475 @@ -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 ----- diff --git a/drivers/hwmon/adt7475.c b/drivers/hwmon/adt7475.c index ec0c43fbcdce..3eb8c5c2f8af 100644 --- a/drivers/hwmon/adt7475.c +++ b/drivers/hwmon/adt7475.c @@ -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 }; -- 2.20.1