Allocate an rphy for an end device
struct sas_rphy * sas_expander_alloc(struct sas_port * parent, enum sas_device_type type);
parent
which port
type
SAS_EDGE_EXPANDER_DEVICE or SAS_FANOUT_EXPANDER_DEVICE
Allocates an SAS remote PHY structure, connected to parent.
SAS PHY allocated or NULL if the allocation failed.