[PATCH v4 3/5] hwmon: (max31790) Show 0 RPM/fault when input disabled

From: Václav Kubernát
Date: Mon Apr 26 2021 - 08:38:20 EST


When fan speed input is disabled, it makes no sense to show values in
fan*_input and fan*_fault.

Signed-off-by: Václav Kubernát <kubernat@xxxxxxxxx>
---
drivers/hwmon/max31790.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/hwmon/max31790.c b/drivers/hwmon/max31790.c
index 82d7b8518743..842749482ba4 100644
--- a/drivers/hwmon/max31790.c
+++ b/drivers/hwmon/max31790.c
@@ -167,6 +167,9 @@ static int max31790_read_fan(struct device *dev, u32 attr, int channel,

switch (attr) {
case hwmon_fan_input:
+ if (!(data->fan_config[channel] & MAX31790_FAN_CFG_TACH_INPUT_EN))
+ return -ENODATA;
+
tach = read_reg_word(regmap, MAX31790_REG_TACH_COUNT(channel));
if (tach < 0)
return tach;
@@ -181,6 +184,11 @@ static int max31790_read_fan(struct device *dev, u32 attr, int channel,
*val = RPM_FROM_REG(tach, get_tach_period(data->fan_dynamics[channel]));
return 0;
case hwmon_fan_fault:
+ if (!(data->fan_config[channel] & MAX31790_FAN_CFG_TACH_INPUT_EN)) {
+ *val = 0;
+ return 0;
+ }
+
if (channel > 6)
fault = read_reg_byte(regmap, MAX31790_REG_FAN_FAULT_STATUS2);
else
--
2.31.1