hwmon: (it87) Make temp3 attribute conditional for IT8782F

On IT8782F, temp3 is only supported if UART6 is disabled.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c
index 071dd60..e7701d9 100644
--- a/drivers/hwmon/it87.c
+++ b/drivers/hwmon/it87.c
@@ -218,6 +218,7 @@
 
 #define IT87_REG_VIN_ENABLE    0x50
 #define IT87_REG_TEMP_ENABLE   0x51
+#define IT87_REG_TEMP_EXTRA    0x55
 #define IT87_REG_BEEP_ENABLE   0x5c
 
 #define IT87_REG_CHIPID        0x58
@@ -238,6 +239,7 @@
 	u8 skip_vid;
 	u8 skip_fan;
 	u8 skip_pwm;
+	u8 skip_temp;
 };
 
 /*
@@ -262,6 +264,7 @@
 	u8 has_fan;		/* Bitfield, fans enabled */
 	u16 fan[5];		/* Register values, possibly combined */
 	u16 fan_min[5];		/* Register values, possibly combined */
+	u8 has_temp;		/* Bitfield, temp sensors enabled */
 	s8 temp[3];		/* Register value */
 	s8 temp_high[3];	/* Register value */
 	s8 temp_low[3];		/* Register value */
@@ -1438,23 +1441,37 @@
 	{ .attrs = it87_attributes_in[8] },
 };
 
-static struct attribute *it87_attributes[] = {
+static struct attribute *it87_attributes_temp[3][6] = {
+{
 	&sensor_dev_attr_temp1_input.dev_attr.attr,
-	&sensor_dev_attr_temp2_input.dev_attr.attr,
-	&sensor_dev_attr_temp3_input.dev_attr.attr,
 	&sensor_dev_attr_temp1_max.dev_attr.attr,
-	&sensor_dev_attr_temp2_max.dev_attr.attr,
-	&sensor_dev_attr_temp3_max.dev_attr.attr,
 	&sensor_dev_attr_temp1_min.dev_attr.attr,
-	&sensor_dev_attr_temp2_min.dev_attr.attr,
-	&sensor_dev_attr_temp3_min.dev_attr.attr,
 	&sensor_dev_attr_temp1_type.dev_attr.attr,
-	&sensor_dev_attr_temp2_type.dev_attr.attr,
-	&sensor_dev_attr_temp3_type.dev_attr.attr,
 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
+	NULL
+} , {
+	&sensor_dev_attr_temp2_input.dev_attr.attr,
+	&sensor_dev_attr_temp2_max.dev_attr.attr,
+	&sensor_dev_attr_temp2_min.dev_attr.attr,
+	&sensor_dev_attr_temp2_type.dev_attr.attr,
 	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
+	NULL
+} , {
+	&sensor_dev_attr_temp3_input.dev_attr.attr,
+	&sensor_dev_attr_temp3_max.dev_attr.attr,
+	&sensor_dev_attr_temp3_min.dev_attr.attr,
+	&sensor_dev_attr_temp3_type.dev_attr.attr,
 	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
+	NULL
+} };
 
+static const struct attribute_group it87_group_temp[3] = {
+	{ .attrs = it87_attributes_temp[0] },
+	{ .attrs = it87_attributes_temp[1] },
+	{ .attrs = it87_attributes_temp[2] },
+};
+
+static struct attribute *it87_attributes[] = {
 	&dev_attr_alarms.attr,
 	&sensor_dev_attr_intrusion0_alarm.dev_attr.attr,
 	&dev_attr_name.attr,
@@ -1477,15 +1494,10 @@
 	NULL
 };
 
-static struct attribute *it87_attributes_beep[] = {
+static struct attribute *it87_attributes_temp_beep[] = {
 	&sensor_dev_attr_temp1_beep.dev_attr.attr,
 	&sensor_dev_attr_temp2_beep.dev_attr.attr,
 	&sensor_dev_attr_temp3_beep.dev_attr.attr,
-	NULL
-};
-
-static const struct attribute_group it87_group_beep = {
-	.attrs = it87_attributes_beep,
 };
 
 static struct attribute *it87_attributes_fan16[5][3+1] = { {
@@ -1870,9 +1882,15 @@
 		 * On IT8782F, UART6 pins overlap with VIN5, VIN6, and VIN7.
 		 * While VIN7 can be routed to the internal voltage divider,
 		 * VIN5 and VIN6 are not available if UART6 is enabled.
+		 *
+		 * Also, temp3 is not available if UART6 is enabled and TEMPIN3
+		 * is the temperature source. Since we can not read the
+		 * temperature source here, skip_temp is preliminary.
 		 */
-		if (uart6)
+		if (uart6) {
 			sio_data->skip_in |= (1 << 5) | (1 << 6);
+			sio_data->skip_temp |= (1 << 2);
+		}
 
 		sio_data->beep_pin = superio_inb(IT87_SIO_BEEP_PIN_REG) & 0x3f;
 	}
@@ -1919,8 +1937,14 @@
 			sysfs_remove_file(&dev->kobj,
 					  it87_attributes_in_beep[i]);
 	}
-	if (sio_data->beep_pin)
-		sysfs_remove_group(&dev->kobj, &it87_group_beep);
+	for (i = 0; i < 3; i++) {
+		if (!(data->has_temp & (1 << i)))
+			continue;
+		sysfs_remove_group(&dev->kobj, &it87_group_temp[i]);
+		if (sio_data->beep_pin)
+			sysfs_remove_file(&dev->kobj,
+					  it87_attributes_temp_beep[i]);
+	}
 	for (i = 0; i < 5; i++) {
 		if (!(data->has_fan & (1 << i)))
 			continue;
@@ -2009,6 +2033,13 @@
 			data->in_scaled |= (1 << 7);	/* in7 is VCCH5V */
 	}
 
+	data->has_temp = 0x07;
+	if (sio_data->skip_temp & (1 << 2)) {
+		if (sio_data->type == it8782
+		    && !(it87_read_value(data, IT87_REG_TEMP_EXTRA) & 0x80))
+			data->has_temp &= ~(1 << 2);
+	}
+
 	/* Initialize the IT87 chip */
 	it87_init_device(pdev);
 
@@ -2031,10 +2062,18 @@
 		}
 	}
 
-	if (sio_data->beep_pin) {
-		err = sysfs_create_group(&dev->kobj, &it87_group_beep);
+	for (i = 0; i < 3; i++) {
+		if (!(data->has_temp & (1 << i)))
+			continue;
+		err = sysfs_create_group(&dev->kobj, &it87_group_temp[i]);
 		if (err)
 			goto error;
+		if (sio_data->beep_pin) {
+			err = sysfs_create_file(&dev->kobj,
+						it87_attributes_temp_beep[i]);
+			if (err)
+				goto error;
+		}
 	}
 
 	/* Do not create fan files for disabled fans */
@@ -2378,6 +2417,8 @@
 			}
 		}
 		for (i = 0; i < 3; i++) {
+			if (!(data->has_temp & (1 << i)))
+				continue;
 			data->temp[i] =
 				it87_read_value(data, IT87_REG_TEMP(i));
 			data->temp_high[i] =