* bytes to transfer, **data - pointer to data pointer.
*
* Returns : -1 when different phase is entered without transferring
* bytes to transfer, **data - pointer to data pointer.
*
* Returns : -1 when different phase is entered without transferring
* is in same phase.
*
* Also, *phase, *count, *data are modified in place.
* is in same phase.
*
* Also, *phase, *count, *data are modified in place.
* bytes to transfer, **data - pointer to data pointer.
*
* Returns : -1 when different phase is entered without transferring
* bytes to transfer, **data - pointer to data pointer.
*
* Returns : -1 when different phase is entered without transferring
* is in same phase.
*
* Also, *phase, *count, *data are modified in place.
* is in same phase.
*
* Also, *phase, *count, *data are modified in place.