Merge: hwmon: Handle failure to register sensor with thermal zone correctly

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/1665

If devm_thermal_zone_of_sensor_register() returns -ENODEV,
report that the sensor was not attached to a thermal zone
but continue to register the hwmon device.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2122394

Upstream Status: git@gitlab.com:redhat/centos-stream/src/kernel/centos-stream-9.git

Signed-off-by: David Marlin <dmarlin@redhat.com>

## Scratch Brew build
https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=49249631

## Description
If an attempt is made to a sensor with a thermal zone and it fails,
the call to devm_thermal_zone_of_sensor_register() may return -ENODEV.
This can result in a crash (NULL pointer dereference).

The hwmon core needs to handle all errors returned from calls
to devm_thermal_zone_of_sensor_register(). If the call fails
with -ENODEV, report that the sensor was not attached to a
thermal zone  but continue to register the hwmon device.

Approved-by: Mark Langsdorf <mlangsdo@redhat.com>
Approved-by: Dean Nelson <dnelson@redhat.com>

Signed-off-by: Herton R. Krzesinski <herton@redhat.com>

Author: Herton R. Krzesinski

drivers/hwmon/hwmon.c

@@ -214,12 +214,14 @@ static int hwmon_thermal_add_sensor(struct device *dev, int index)
 
 	tzd = devm_thermal_zone_of_sensor_register(dev, index, tdata,
 						   &hwmon_thermal_ops);
-	/*
-	 * If CONFIG_THERMAL_OF is disabled, this returns -ENODEV,
-	 * so ignore that error but forward any other error.
-	 */
-	if (IS_ERR(tzd) && (PTR_ERR(tzd) != -ENODEV))
-		return PTR_ERR(tzd);
+	if (IS_ERR(tzd)) {
+		if (PTR_ERR(tzd) != -ENODEV)
+			return PTR_ERR(tzd);
+		dev_info(dev, "temp%d_input not attached to any thermal zone\n",
+			 index + 1);
+		devm_kfree(dev, tdata);
+		return 0;
+	}
 
 	err = devm_add_action(dev, hwmon_thermal_remove_sensor, &tdata->node);
 	if (err)