hwmon: (emc2103) fix unable to change fan pwm1_enable attribute

This patch fixes a bug which does not let FAN mode to be changed from
sysfs(pwm1_enable). i.e pwm1_enable can not be set to 3, it will always
remain at 0.

This is caused because the device driver handles the result of
"read_u8_from_i2c(client, REG_FAN_CONF1, &conf_reg)" incorrectly. The
driver thinks an error has occurred if the (result != 0). This has been
fixed by changing the condition to (result < 0).
Signed-off-by: Vishwas M <vishwas.reddy.vr@gmail.com>
Link: https://lore.kernel.org/r/20200707142747.118414-1-vishwas.reddy.vr@gmail.com
Fixes: 9df7305b ("hwmon: Add driver for SMSC EMC2103 temperature monitor and fan controller")
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/emc2103.c

@@ -443,7 +443,7 @@ static ssize_t pwm1_enable_store(struct device *dev,
 	}
 
 	result = read_u8_from_i2c(client, REG_FAN_CONF1, &conf_reg);
-	if (result) {
+	if (result < 0) {
 		count = result;
 		goto err;
 	}