pci_save_state(dis_dev); pci_clear_master(dis_dev); pci_disable_device(dis_dev); pci_set_power_state(dis_dev, PCI_D3cold);
and I see similar functions on /sys/dev/pci/pci.c int pcidetach(struct device *, int); void pci_powerdown(struct pci_softc *); int pci_set_powerstate(pci_chipset_tag_t pc, pcitag_t tag, int state)