int (*get_max_bus_speed)(struct slot *slot, enum pci_bus_speed *speed);
int (*get_cur_bus_speed)(struct slot *slot, enum pci_bus_speed *speed);
int (*get_max_lnk_width)(struct slot *slot, enum pcie_link_width *val);
int (*get_max_bus_speed)(struct slot *slot, enum pci_bus_speed *speed);
int (*get_cur_bus_speed)(struct slot *slot, enum pci_bus_speed *speed);
int (*get_max_lnk_width)(struct slot *slot, enum pcie_link_width *val);