hwmon: (w83627ehf) Be more careful when changing VID input level

The VID input level change has been reported to cause trouble. Be more
careful in this respect:
* Only change the level on the W83627EHF/EHG. The W83627DHG is more
  complex in this respect.
* Don't change the level if the VID pins are in output mode.
* Only set the level to TTL if VRM 9.x is used.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NMark M. Hoffman <mhoffman@lightlink.com>

drivers/hwmon/w83627ehf.c

@@ -1276,23 +1276,31 @@ static int __devinit w83627ehf_probe(struct platform_device *pdev)
 
 	data->vrm = vid_which_vrm();
 	superio_enter(sio_data->sioreg);
-	/* Set VID input sensibility if needed. In theory the BIOS should
-	   have set it, but in practice it's not always the case. */
-	en_vrm10 = superio_inb(sio_data->sioreg, SIO_REG_EN_VRM10);
-	if ((en_vrm10 & 0x08) && data->vrm != 100) {
-		dev_warn(dev, "Setting VID input voltage to TTL\n");
-		superio_outb(sio_data->sioreg, SIO_REG_EN_VRM10,
-			     en_vrm10 & ~0x08);
-	} else if (!(en_vrm10 & 0x08) && data->vrm == 100) {
-		dev_warn(dev, "Setting VID input voltage to VRM10\n");
-		superio_outb(sio_data->sioreg, SIO_REG_EN_VRM10,
-			     en_vrm10 | 0x08);
-	}
 	/* Read VID value */
 	superio_select(sio_data->sioreg, W83627EHF_LD_HWM);
-	if (superio_inb(sio_data->sioreg, SIO_REG_VID_CTRL) & 0x80)
+	if (superio_inb(sio_data->sioreg, SIO_REG_VID_CTRL) & 0x80) {
+		/* Set VID input sensibility if needed. In theory the BIOS
+		   should have set it, but in practice it's not always the
+		   case. We only do it for the W83627EHF/EHG because the
+		   W83627DHG is more complex in this respect. */
+		if (sio_data->kind == w83627ehf) {
+			en_vrm10 = superio_inb(sio_data->sioreg,
+					       SIO_REG_EN_VRM10);
+			if ((en_vrm10 & 0x08) && data->vrm == 90) {
+				dev_warn(dev, "Setting VID input voltage to "
+					 "TTL\n");
+				superio_outb(sio_data->sioreg, SIO_REG_EN_VRM10,
+					     en_vrm10 & ~0x08);
+			} else if (!(en_vrm10 & 0x08) && data->vrm == 100) {
+				dev_warn(dev, "Setting VID input voltage to "
+					 "VRM10\n");
+				superio_outb(sio_data->sioreg, SIO_REG_EN_VRM10,
+					     en_vrm10 | 0x08);
+			}
+		}
+
 		data->vid = superio_inb(sio_data->sioreg, SIO_REG_VID_DATA) & 0x3f;
-	else {
+	} else {
 		dev_info(dev, "VID pins in output mode, CPU VID not "
 			 "available\n");
 		data->vid = 0x3f;