i2c_io_req_set_receive_buf
!i2c_io_req_set_receive_buf(req->io_i2c, req->io_rdata,
if (!i2c_io_req_set_receive_buf(req, &data, sizeof (data))) {
extern bool i2c_io_req_set_receive_buf(i2c_io_req_t *, void *, size_t);
if (!i2c_io_req_set_receive_buf(req, rbuf, sizeof (rbuf))) {