A fan speed tolerance only makes sense if a fan target speed has been configured in the first place. Otherwise we get odd output such as
fan1_target:0 fan1_tolerance:337500 Only display values other than 0 if a fan target speed has been configured. Signed-off-by: Guenter Roeck <[email protected]> --- drivers/hwmon/nct6775.c | 32 +++++++++++++++++++------------- 1 file changed, 19 insertions(+), 13 deletions(-) diff --git a/drivers/hwmon/nct6775.c b/drivers/hwmon/nct6775.c index 2b493d0682af..0bb2c24d21a9 100644 --- a/drivers/hwmon/nct6775.c +++ b/drivers/hwmon/nct6775.c @@ -2847,6 +2847,8 @@ store_temp_tolerance(struct device *dev, struct device_attribute *attr, * Fan speed tolerance is a tricky beast, since the associated register is * a tick counter, but the value is reported and configured as rpm. * Compute resulting low and high rpm values and report the difference. + * A target speed tolerance only makes sense if a target speed has been + * configured, so only display values other than 0 if that is the case. */ static ssize_t show_speed_tolerance(struct device *dev, struct device_attribute *attr, @@ -2855,19 +2857,23 @@ show_speed_tolerance(struct device *dev, struct device_attribute *attr, struct nct6775_data *data = nct6775_update_device(dev); struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr); int nr = sattr->index; - int low = data->target_speed[nr] - data->target_speed_tolerance[nr]; - int high = data->target_speed[nr] + data->target_speed_tolerance[nr]; - int tolerance; - - if (low <= 0) - low = 1; - if (high > 0xffff) - high = 0xffff; - if (high < low) - high = low; - - tolerance = (fan_from_reg16(low, data->fan_div[nr]) - - fan_from_reg16(high, data->fan_div[nr])) / 2; + int target = data->target_speed[nr]; + int tolerance = 0; + + if (target) { + int low = target - data->target_speed_tolerance[nr]; + int high = target + data->target_speed_tolerance[nr]; + + if (low <= 0) + low = 1; + if (high > 0xffff) + high = 0xffff; + if (high < low) + high = low; + + tolerance = (fan_from_reg16(low, data->fan_div[nr]) + - fan_from_reg16(high, data->fan_div[nr])) / 2; + } return sprintf(buf, "%d\n", tolerance); } -- 2.7.4
