CCK_DISPLAY_CLOCK_CONTROL
val = vlv_cck_read(display->drm, CCK_DISPLAY_CLOCK_CONTROL);
vlv_cck_write(display->drm, CCK_DISPLAY_CLOCK_CONTROL, val);
ret = poll_timeout_us(val = vlv_cck_read(display->drm, CCK_DISPLAY_CLOCK_CONTROL),
return vlv_clock_get_cck(drm, "cdclk", CCK_DISPLAY_CLOCK_CONTROL,