1 files changed, 24 insertions, 3 deletions

diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c
index 2f782e3f9a2b..0ffe84d190bb 100644
--- a/drivers/hwmon/it87.c
+++ b/drivers/hwmon/it87.c
@@ -125,6 +125,7 @@ superio_exit(void)
 
 /* Logical device 7 registers (IT8712F and later) */
 #define IT87_SIO_GPIO3_REG      0x27
+#define IT87_SIO_GPIO5_REG      0x29
 #define IT87_SIO_PINX2_REG      0x2c    /* Pin selection */
 #define IT87_SIO_VID_REG        0xfc    /* VID value */
 
@@ -245,8 +246,9 @@ struct it87_sio_data {
         /* Values read from Super-I/O config space */
         u8 revision;
         u8 vid_value;
+        /* Features skipped based on config or DMI */
         u8 skip_vid;
-        /* Values set based on DMI strings */
+        u8 skip_fan;
         u8 skip_pwm;
 };
 
@@ -1044,6 +1046,19 @@ static int __init it87_find(unsigned short *address,
                         sio_data->skip_vid = 1;
                 }
 
+                /* Check if fan3 is there or not */
+                if (reg & (1 << 6))
+                        sio_data->skip_pwm |= (1 << 2);
+                if (reg & (1 << 7))
+                        sio_data->skip_fan |= (1 << 2);
+
+                /* Check if fan2 is there or not */
+                reg = superio_inb(IT87_SIO_GPIO5_REG);
+                if (reg & (1 << 1))
+                        sio_data->skip_pwm |= (1 << 1);
+                if (reg & (1 << 2))
+                        sio_data->skip_fan |= (1 << 1);
+
                 if ((sio_data->type == it8718 || sio_data->type == it8720)
                  && !(sio_data->skip_vid))
                         sio_data->vid_value = superio_inb(IT87_SIO_VID_REG);
@@ -1367,8 +1382,10 @@ static int __devinit it87_check_pwm(struct device *dev)
 /* Called when we have found a new IT87. */
 static void __devinit it87_init_device(struct platform_device *pdev)
 {
+        struct it87_sio_data *sio_data = pdev->dev.platform_data;
         struct it87_data *data = platform_get_drvdata(pdev);
         int tmp, i;
+        u8 mask;
 
         /* initialize to sane defaults:
          * - if the chip is in manual pwm mode, this will be overwritten with
@@ -1414,10 +1431,11 @@ static void __devinit it87_init_device(struct platform_device *pdev)
         }
 
         /* Check if tachometers are reset manually or by some reason */
+        mask = 0x70 & ~(sio_data->skip_fan << 4);
         data->fan_main_ctrl = it87_read_value(data, IT87_REG_FAN_MAIN_CTRL);
-        if ((data->fan_main_ctrl & 0x70) == 0) {
+        if ((data->fan_main_ctrl & mask) == 0) {
                 /* Enable all fan tachometers */
-                data->fan_main_ctrl |= 0x70;
+                data->fan_main_ctrl |= mask;
                 it87_write_value(data, IT87_REG_FAN_MAIN_CTRL, data->fan_main_ctrl);
         }
         data->has_fan = (data->fan_main_ctrl >> 4) & 0x07;
@@ -1440,6 +1458,9 @@ static void __devinit it87_init_device(struct platform_device *pdev)
                 }
         }
 
+        /* Fan input pins may be used for alternative functions */
+        data->has_fan &= ~sio_data->skip_fan;
+
         /* Set current fan mode registers and the default settings for the
          * other mode registers */
         for (i = 0; i < 3; i++) {