diff --git a/src/i830_i2c.c b/src/i830_i2c.c
index d80229d..361bdf5 100644
--- a/src/i830_i2c.c
+++ b/src/i830_i2c.c
@@ -274,6 +274,8 @@ i830I2CGetBits(I2CBusPtr b, int *clock, int *data)
     I830Ptr pI830 = I830PTR(pScrn);
     CARD32 val;
 
+    /* invoke write cycle to strobe new datum */
+    OUTREG(b->DriverPrivate.uval, 0);
     val = INREG(b->DriverPrivate.uval);
 
     /*
@@ -337,6 +339,13 @@ i830I2CPutBits(I2CBusPtr b, int clock, int data)
     
     OUTREG(b->DriverPrivate.uval, reserved | data_bits | clock_bits);
     POSTING_READ(b->DriverPrivate.uval);
+
+    /* lock DFlipFlop ? copied from vbios code */
+    data_bits &= ~GPIO_DATA_DIR_MASK;
+    clock_bits &= ~GPIO_CLOCK_DIR_MASK;
+    OUTREG(b->DriverPrivate.uval, reserved | data_bits | clock_bits);
+
+    POSTING_READ(b->DriverPrivate.uval);
 }
 
 #endif