static int mercury_cfg_read()

in lba_pci.c [480:505]

• 23 lines of code
• 7 McCabe index (conditional complexity)

static int mercury_cfg_read(struct pci_bus *bus, unsigned int devfn, int pos, int size, u32 *data)
{
	struct lba_device *d = LBA_DEV(parisc_walk_tree(bus->bridge));
	u32 local_bus = (bus->parent == NULL) ? 0 : bus->busn_res.start;
	u32 tok = LBA_CFG_TOK(local_bus, devfn);
	void __iomem *data_reg = d->hba.base_addr + LBA_PCI_CFG_DATA;

	if ((pos > 255) || (devfn > 255))
		return -EINVAL;

	LBA_CFG_TR4_ADDR_SETUP(d, tok | pos);
	switch(size) {
	case 1:
		*data = READ_REG8(data_reg + (pos & 3));
		break;
	case 2:
		*data = READ_REG16(data_reg + (pos & 2));
		break;
	case 4:
		*data = READ_REG32(data_reg);             break;
		break;
	}

	DBG_CFG("mercury_cfg_read(%x+%2x) -> 0x%x\n", tok, pos, *data);
	return 0;
}