hwmon: (it87) Split temperature sensor detection to separate function

The temperature sensor type will need to be used in multiple places, so
split it out into its own function.
Signed-off-by: Frank Crawford <frank@crawford.emu.id.au>
Link: https://lore.kernel.org/r/20230707123005.956415-2-frank@crawford.emu.id.au
[groeck: Dropped unnecessary 'type' variable in show_temp_type()]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/it87.c

@@ -1159,28 +1159,43 @@ static SENSOR_DEVICE_ATTR_2(temp4_input, S_IRUGO, show_temp, NULL, 3, 0);
 static SENSOR_DEVICE_ATTR_2(temp5_input, S_IRUGO, show_temp, NULL, 4, 0);
 static SENSOR_DEVICE_ATTR_2(temp6_input, S_IRUGO, show_temp, NULL, 5, 0);
 
+static int get_temp_type(struct it87_data *data, int index)
+{
+	/*
+	 * 2 is deprecated;
+	 * 3 = thermal diode;
+	 * 4 = thermistor;
+	 * 5 = AMDTSI;
+	 * 6 = Intel PECI;
+	 * 0 = disabled
+	 */
+	u8 reg, extra;
+	int type = 0;
+
+	reg = data->sensor;	/* In case value is updated while used */
+	extra = data->extra;
+
+	if ((has_temp_peci(data, index) && (reg >> 6 == index + 1)) ||
+	    (has_temp_old_peci(data, index) && (extra & 0x80)))
+		type = 6;	/* Intel PECI */
+	else if (reg & BIT(index))
+		type = 3;	/* thermal diode */
+	else if (reg & BIT(index + 3))
+		type = 4;	/* thermistor */
+
+	return type;
+}
+
 static ssize_t show_temp_type(struct device *dev, struct device_attribute *attr,
 			      char *buf)
 {
 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
-	int nr = sensor_attr->index;
 	struct it87_data *data = it87_update_device(dev);
-	u8 reg, extra;
 
 	if (IS_ERR(data))
 		return PTR_ERR(data);
 
-	reg = data->sensor;	/* In case value is updated while used */
-	extra = data->extra;
-
-	if ((has_temp_peci(data, nr) && (reg >> 6 == nr + 1)) ||
-	    (has_temp_old_peci(data, nr) && (extra & 0x80)))
-		return sprintf(buf, "6\n");  /* Intel PECI */
-	if (reg & (1 << nr))
-		return sprintf(buf, "3\n");  /* thermal diode */
-	if (reg & (8 << nr))
-		return sprintf(buf, "4\n");  /* thermistor */
-	return sprintf(buf, "0\n");      /* disabled */
+	return sprintf(buf, "%d\n", get_temp_type(data, sensor_attr->index));
 }
 
 static ssize_t set_temp_type(struct device *dev, struct device_attribute *attr,