i2csim_req_t
i2csim_req_t *req = &simd->simd_req;
i2csim_req_t simd_req;
i2csim_req_t req;
int ret = ddi_copyout(&req, (void *)arg, sizeof (i2csim_req_t),
i2csim_req_t req;
if (ddi_copyin((void *)arg, &req, sizeof (i2csim_req_t),