ehci_qh
struct ehci_qh *next;
struct ehci_qh *prev;
struct ehci_qh *obj_next;
typedef struct ehci_qh ehci_qh_t;
struct ehci_qh *sc_async_p_last;
struct ehci_qh *sc_intr_p_last[EHCI_VIRTUAL_FRAMELIST_COUNT];