hwmon: (nct7904) Fix the incorrect value of vsen_mask & tcpu_mask & t…

…emp_mode in nct7904_data struct.

Voltage sensors overlap with external temperature sensors. Detect
the multi-function of voltage, thermal diode, thermistor and
reserved from register VT_ADC_MD_REG to set value of vsen_mask &
tcpu_mask & temp_mode in nct7904_data struct. If the value is
reserved, needs to disable the vsen_mask & tcpu_mask.

Signed-off-by: amy.shih <amy.shih@advantech.com.tw>
Link: https://lore.kernel.org/r/20191014082451.2895-1-Amy.Shih@advantech.com.tw
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/nct7904.c

@@ -82,6 +82,10 @@
 #define FANCTL1_FMR_REG		0x00	/* Bank 3; 1 reg per channel */
 #define FANCTL1_OUT_REG		0x10	/* Bank 3; 1 reg per channel */
 
+#define VOLT_MONITOR_MODE	0x0
+#define THERMAL_DIODE_MODE	0x1
+#define THERMISTOR_MODE		0x3
+
 #define ENABLE_TSI	BIT(1)
 
 static const unsigned short normal_i2c[] = {
@@ -935,11 +939,16 @@ static int nct7904_probe(struct i2c_client *client,
 	for (i = 0; i < 4; i++) {
 		val = (ret >> (i * 2)) & 0x03;
 		bit = (1 << i);
-		if (val == 0) {
+		if (val == VOLT_MONITOR_MODE) {
 			data->tcpu_mask &= ~bit;
+		} else if (val == THERMAL_DIODE_MODE && i < 2) {
+			data->temp_mode |= bit;
+			data->vsen_mask &= ~(0x06 << (i * 2));
+		} else if (val == THERMISTOR_MODE) {
+			data->vsen_mask &= ~(0x02 << (i * 2));
 		} else {
-			if (val == 0x1 || val == 0x2)
-				data->temp_mode |= bit;
+			/* Reserved */
+			data->tcpu_mask &= ~bit;
 			data->vsen_mask &= ~(0x06 << (i * 2));
 		}
 	}