VDC_READ_WAITING
vdc->read_state = VDC_READ_WAITING;
if ((vdc->read_state == VDC_READ_WAITING) ||
if ((vdc->read_state == VDC_READ_WAITING) ||
ASSERT(vdcp->read_state != VDC_READ_WAITING);
if ((vdc->read_state == VDC_READ_WAITING) ||