IVTV_F_S_DMA_HAS_VBI
clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags);
set_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags);
if (test_and_clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags)) {
if (test_and_clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags)) {