UCOM_LS_RING
mask |= UCOM_LS_RING;
if (notch_bits & UCOM_LS_RING)
(prev_value & UCOM_LS_RING) ? 1 : 0);
if (any_bits & UCOM_LS_RING)
(last_value & UCOM_LS_RING) ? 1 : 0);
ucom_line_state(sc, UCOM_LS_RING, 0);
ucom_line_state(sc, 0, UCOM_LS_RING);