hwmon: (applesmc) check status earlier.

clang static analysis reports this representative problem

applesmc.c:758:10: warning: 1st function call argument is an
uninitialized value
left = be16_to_cpu(*(__be16 *)(buffer + 6)) >> 2;
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

buffer is filled by the earlier call

ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, ...

This problem is reported because a goto skips the status check.
Other similar problems use data from applesmc_read_key before checking
the status. So move the checks to before the use.

Signed-off-by: Tom Rix <[e-mail]>
Reviewed-by: Henrik Rydberg <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Guenter Roeck <[e-mail]>

drivers/hwmon/applesmc.c

···
 	}
 
 	ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, buffer, data_length);
+	if (ret)
+		goto out;
 	/* newer macbooks report a single 10-bit bigendian value */
 	if (data_length == 10) {
 		left = be16_to_cpu(*(__be16 *)(buffer + 6)) >> 2;
 		goto out;
 	}
 	left = buffer[2];
+
+	ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length);
 	if (ret)
 		goto out;
-	ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length);
 	right = buffer[2];
 
 out:
···
 		  to_index(attr));
 
 	ret = applesmc_read_key(newkey, buffer, 2);
-	speed = ((buffer[0] << 8 | buffer[1]) >> 2);
-
 	if (ret)
 		return ret;
-	else
-		return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed);
+
+	speed = ((buffer[0] << 8 | buffer[1]) >> 2);
+	return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed);
 }
 
 static ssize_t applesmc_store_fan_speed(struct device *dev,
···
 	u8 buffer[2];
 
 	ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
-	manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01;
-
 	if (ret)
 		return ret;
-	else
-		return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual);
+
+	manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01;
+	return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual);
 }
 
 static ssize_t applesmc_store_fan_manual(struct device *dev,
···
 		return -EINVAL;
 
 	ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
-	val = (buffer[0] << 8 | buffer[1]);
 	if (ret)
 		goto out;
+
+	val = (buffer[0] << 8 | buffer[1]);
 
 	if (input)
 		val = val | (0x01 << to_index(attr));
···
 	u32 count;
 
 	ret = applesmc_read_key(KEY_COUNT_KEY, buffer, 4);
-	count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) +
-						((u32)buffer[2]<<8) + buffer[3];
-
 	if (ret)
 		return ret;
-	else
-		return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count);
+
+	count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) +
+						((u32)buffer[2]<<8) + buffer[3];
+	return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count);
 }
 
 static ssize_t applesmc_key_at_index_read_show(struct device *dev,