DPIO_C_POLL
dpio_caps_t bits[3] = { DPIO_C_READ, DPIO_C_WRITE, DPIO_C_POLL };
*caps |= DPIO_C_POLL;
if ((caps & DPIO_C_READ) != 0 && (sup_caps & DPIO_C_POLL) != 0) {
caps |= DPIO_C_POLL;