hwmon/f71882fg: Only allow negative auto point temps if fan_neg_temp is enabled

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>

1 files changed, 16 insertions, 2 deletions

diff --git a/drivers/hwmon/f71882fg.c b/drivers/hwmon/f71882fg.c
index 6c3de065e04b..67ac85870592 100644
--- a/drivers/hwmon/f71882fg.c
+++ b/drivers/hwmon/f71882fg.c
@@ -84,6 +84,9 @@
 
 #define F71882FG_REG_FAN_HYST(nr)       (0x98 + (nr))
 
+#define F71882FG_REG_FAN_FAULT_T        0x9F
+#define F71882FG_FAN_NEG_TEMP_EN        0x20
+
 #define F71882FG_REG_POINT_PWM(pwm, point)      (0xAA + (point) + (16 * (pwm)))
 #define F71882FG_REG_POINT_TEMP(pwm, point)     (0xA6 + (point) + (16 * (pwm)))
 #define F71882FG_REG_POINT_MAPPING(nr)          (0xAF + 16 * (nr))
@@ -127,6 +130,7 @@ struct f71882fg_data {
         struct mutex update_lock;
         int temp_start;                 /* temp numbering start (0 or 1) */
         char valid;                     /* !=0 if following fields are valid */
+        char auto_point_temp_signed;
         unsigned long last_updated;     /* In jiffies */
         unsigned long last_limits;      /* In jiffies */
 
@@ -1853,7 +1857,7 @@ static ssize_t store_pwm_auto_point_temp(struct device *dev,
 
         val /= 1000;
 
-        if (data->type == f71889fg)
+        if (data->auto_point_temp_signed)
                 val = SENSORS_LIMIT(val, -128, 127);
         else
                 val = SENSORS_LIMIT(val, 0, 127);
@@ -1900,7 +1904,7 @@ static int __devinit f71882fg_probe(struct platform_device *pdev)
         struct f71882fg_data *data;
         struct f71882fg_sio_data *sio_data = pdev->dev.platform_data;
         int err, i, nr_fans = (sio_data->type == f71882fg) ? 4 : 3;
-        u8 start_reg;
+        u8 start_reg, reg;
 
         data = kzalloc(sizeof(struct f71882fg_data), GFP_KERNEL);
         if (!data)
@@ -1970,6 +1974,16 @@ static int __devinit f71882fg_probe(struct platform_device *pdev)
         }
 
         if (start_reg & 0x02) {
+                switch (data->type) {
+                case f71889fg:
+                        reg = f71882fg_read8(data, F71882FG_REG_FAN_FAULT_T);
+                        if (reg & F71882FG_FAN_NEG_TEMP_EN)
+                                data->auto_point_temp_signed = 1;
+                        break;
+                default:
+                        break;
+                }
+
                 data->pwm_enable =
                         f71882fg_read8(data, F71882FG_REG_PWM_ENABLE);