ATAPI_DELAY
if (wdc_wait_for_unbusy(chp, ATAPI_DELAY, wait_flags, &tfd))
if (wdc_wait_for_unbusy(chp, ATAPI_DELAY, wait_flags, &tfd) != 0) {
if (wdc_wait_for_unbusy(chp, ATAPI_DELAY, wait_flags, &tfd))
switch (wdc_wait_for_unbusy(chp, ATAPI_DELAY, wait_flags, &tfd)) {