It is not called, and unused.
const struct pci_device_id *id_table; /* must be non-NULL for probe to be called */
int (*probe) (struct pci_dev *dev, const struct pci_device_id *id); /* New device inserted */
void (*remove) (struct pci_dev *dev); /* Device removed (NULL if not a hot-plug capable driver) */
- int (*save_state) (struct pci_dev *dev, u32 state); /* Save Device Context */
int (*suspend) (struct pci_dev *dev, u32 state); /* Device suspended */
int (*resume) (struct pci_dev *dev); /* Device woken up */
int (*enable_wake) (struct pci_dev *dev, u32 state, int enable); /* Enable wake event */