diff --git a/src/i810_reg.h b/src/i810_reg.h
index 9eeddc9..466e63d 100644
--- a/src/i810_reg.h
+++ b/src/i810_reg.h
@@ -103,6 +103,14 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #define HOTKEY_SWITCH			0x20
 #define HOTKEY_TOGGLE			0x10
 
+/* GMBus registers */
+#define GMBUS0                  0x5100
+#define GMBUS1                  0x5104
+#define GMBUS2                  0x5108
+#define GMBUS3                  0x510c
+#define GMBUS4                  0x5110
+#define GMBUS5                  0x5120
+                                
 /* Blitter control, p378
  */
 #define BITBLT_CNTL        0x7000c
diff --git a/src/i830_debug.c b/src/i830_debug.c
index 7d0c0a0..8c8e473 100644
--- a/src/i830_debug.c
+++ b/src/i830_debug.c
@@ -627,6 +627,20 @@ static struct i830SnapshotRec {
     DEFINEREG(MI_ARB_STATE),
     DEFINEREG(MI_RDRET_STATE),
     DEFINEREG(ECOSKPD),
+    DEFINEREG(GPIOA),
+    DEFINEREG(GPIOB),
+    DEFINEREG(GPIOC),
+    DEFINEREG(GPIOD),
+    DEFINEREG(GPIOE),
+    DEFINEREG(GPIOF),
+    DEFINEREG(GPIOG),
+    DEFINEREG(GPIOH),
+    DEFINEREG(GMBUS0),
+    DEFINEREG(GMBUS1),
+    DEFINEREG(GMBUS2),
+    DEFINEREG(GMBUS3),
+    DEFINEREG(GMBUS4),
+    DEFINEREG(GMBUS5),
 #if 0
     DEFINEREG2(FENCE_NEW + 0, i810_debug_fence_new),
     DEFINEREG2(FENCE_NEW + 8, i810_debug_fence_new),
diff --git a/src/i830_i2c.c b/src/i830_i2c.c
index d80229d..589a844 100644
--- a/src/i830_i2c.c
+++ b/src/i830_i2c.c
@@ -347,6 +347,8 @@ I830I2CInit(ScrnInfoPtr pScrn, I2CBusPtr *bus_ptr, int i2c_reg, char *name)
     I2CBusPtr pI2CBus;
     I830Ptr pI830 = I830PTR(pScrn);
 
+    OUTREG(GMBUS0, 0);
+
     pI2CBus = xf86CreateI2CBusRec();
 
     if (!pI2CBus)