ST_M2M_OPEN
#define gsc_m2m_opened(dev) test_bit(ST_M2M_OPEN, &(dev)->state)
set_bit(ST_M2M_OPEN, &gsc->state);
clear_bit(ST_M2M_OPEN, &gsc->state);
opened = test_bit(ST_M2M_OPEN, &bdisp->state);
set_bit(ST_M2M_OPEN, &bdisp->state);
clear_bit(ST_M2M_OPEN, &bdisp->state);