hwmon: (nct6775) Fix writing pwmX_mode

BugLink: https://bugs.launchpad.net/bugs/1775771

[ Upstream commit 415eb2a1 ]

pwmX_mode is defined in the ABI as 0=DC mode, 1=pwm mode. The chip
register bit is set to 1 for DC mode. This got mixed up, and writing
1 into pwmX_mode resulted in DC mode enabled. Fix it up by using
the ABI definition throughout the driver for consistency.

Fixes: 77eb5b37 ("hwmon: (nct6775) Add support for pwm, pwm_mode, ... ")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

drivers/hwmon/nct6775.c

@@ -1390,7 +1390,7 @@ static void nct6775_update_pwm(struct device *dev)
 		duty_is_dc = data->REG_PWM_MODE[i] &&
 		  (nct6775_read_value(data, data->REG_PWM_MODE[i])
 		   & data->PWM_MODE_MASK[i]);
-		data->pwm_mode[i] = duty_is_dc;
+		data->pwm_mode[i] = !duty_is_dc;
 
 		fanmodecfg = nct6775_read_value(data, data->REG_FAN_MODE[i]);
 		for (j = 0; j < ARRAY_SIZE(data->REG_PWM); j++) {
@@ -2267,7 +2267,7 @@ show_pwm_mode(struct device *dev, struct device_attribute *attr, char *buf)
 	struct nct6775_data *data = nct6775_update_device(dev);
 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
 
-	return sprintf(buf, "%d\n", !data->pwm_mode[sattr->index]);
+	return sprintf(buf, "%d\n", data->pwm_mode[sattr->index]);
 }
 
 static ssize_t
@@ -2288,9 +2288,9 @@ store_pwm_mode(struct device *dev, struct device_attribute *attr,
 	if (val > 1)
 		return -EINVAL;
 
-	/* Setting DC mode is not supported for all chips/channels */
+	/* Setting DC mode (0) is not supported for all chips/channels */
 	if (data->REG_PWM_MODE[nr] == 0) {
-		if (val)
+		if (!val)
 			return -EINVAL;
 		return count;
 	}
@@ -2299,7 +2299,7 @@ store_pwm_mode(struct device *dev, struct device_attribute *attr,
 	data->pwm_mode[nr] = val;
 	reg = nct6775_read_value(data, data->REG_PWM_MODE[nr]);
 	reg &= ~data->PWM_MODE_MASK[nr];
-	if (val)
+	if (!val)
 		reg |= data->PWM_MODE_MASK[nr];
 	nct6775_write_value(data, data->REG_PWM_MODE[nr], reg);
 	mutex_unlock(&data->update_lock);