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: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>

1 files changed, 22 insertions, 14 deletions

diff --git a/drivers/hwmon/w83627ehf.c b/drivers/hwmon/w83627ehf.c
index b15c6a998b72..d5aa25ce5dbd 100644
--- a/drivers/hwmon/w83627ehf.c
+++ b/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;