[PATCH 4.19 115/133] hwmon: (emc2103) fix unable to change fan pwm1_enable attribute

[Greg Kroah-Hartman]

From: Vishwas M <vishwas.reddy.vr@xxxxxxxxx>

commit 14b0e83dc4f1e52b94acaeb85a18fd7fdd46d2dc upstream.

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@xxxxxxxxx>
Link: https://lore.kernel.org/r/20200707142747.118414-1-vishwas.reddy.vr@xxxxxxxxx
Fixes: 9df7305b5a86 ("hwmon: Add driver for SMSC EMC2103 temperature monitor and fan controller")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/hwmon/emc2103.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/hwmon/emc2103.c
+++ b/drivers/hwmon/emc2103.c
@@ -454,7 +454,7 @@ static ssize_t pwm1_enable_store(struct
 	}
 
 	result = read_u8_from_i2c(client, REG_FAN_CONF1, &conf_reg);
-	if (result) {
+	if (result < 0) {
 		count = result;
 		goto err;
 	}