diff --git a/common/hw-gfx-gma-i2c.adb b/common/hw-gfx-gma-i2c.adb
index 3d41174..a958e26 100644
--- a/common/hw-gfx-gma-i2c.adb
+++ b/common/hw-gfx-gma-i2c.adb
@@ -233,7 +233,7 @@
             Registers.Wait_Set_Mask
               (Register => GMBUS_Regs (2),
                Mask     => GMBUS2_HARDWARE_READY,
-               TOut_MS  => 110);
+               TOut_MS  => 500);
 
             Registers.Read (GMBUS_Regs (2), GMBUS2);
             Success :=  (GMBUS2 and GMBUS2_HARDWARE_READY) /= 0 and