[RFT PATCH 2/3] hwmon: (nct6775) Fix swapped temperature tolerance register writes

[Guenter Roeck <linux@roeck-us.net>]

sensor_dev_template_pwm_temp_tolerance uses index 0 (backed by
REG_FAN_MODE via pwm_update_registers()) while
sensor_dev_template_pwm_crit_temp_tolerance uses index 1 (backed by
REG_CRITICAL_TEMP_TOLERANCE). However, store_temp_tolerance() checks
if (index) with inverted branches.

As a result, writing to pwm*_temp_tolerance writes the new tolerance to
REG_CRITICAL_TEMP_TOLERANCE instead of REG_FAN_MODE, while writing to
pwm*_crit_temp_tolerance updates REG_FAN_MODE with temp_tolerance[0] and
leaves REG_CRITICAL_TEMP_TOLERANCE unchanged.

Invert the index check in store_temp_tolerance() so index 0 updates fan
mode registers via pwm_update_registers() and index 1 writes to
REG_CRITICAL_TEMP_TOLERANCE.

Fixes: cdcaeceb74ff ("hwmon: (nct6775) Add support for automatic fan control")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev
Cc: Anton Lundin <glance@ac2.se>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 drivers/hwmon/nct6775-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/nct6775-core.c b/drivers/hwmon/nct6775-core.c
index 192b52750db5..1d63747a2f38 100644
--- a/drivers/hwmon/nct6775-core.c
+++ b/drivers/hwmon/nct6775-core.c
@@ -3053,7 +3053,7 @@ store_temp_tolerance(struct device *dev, struct device_attribute *attr,
 
 	mutex_lock(&data->update_lock);
 	data->temp_tolerance[index][nr] = val;
-	if (index)
+	if (!index)
 		err = pwm_update_registers(data, nr);
 	else
 		err = nct6775_write_value(data, data->REG_CRITICAL_TEMP_TOLERANCE[nr], val);
-- 
2.45.2