pci_config_read
.read = pci_config_read,
.read = pci_config_read,
pci_config_read(NULL, 0, 0x70c, 4, &val);
pci_config_read(NULL, 0, 4, 4, &val);
pci_config_read(dev->bus, 0, PCI_BASE_ADDRESS_0, 4, &val);