static u16 ssb_pcie_mdio_read()

in driver_pcicore.c [605:643]

• 35 lines of code
• 5 McCabe index (conditional complexity)

static u16 ssb_pcie_mdio_read(struct ssb_pcicore *pc, u8 device, u8 address)
{
	const u16 mdio_control = 0x128;
	const u16 mdio_data = 0x12C;
	int max_retries = 10;
	u16 ret = 0;
	u32 v;
	int i;

	v = 0x80; /* Enable Preamble Sequence */
	v |= 0x2; /* MDIO Clock Divisor */
	pcicore_write32(pc, mdio_control, v);

	if (pc->dev->id.revision >= 10) {
		max_retries = 200;
		ssb_pcie_mdio_set_phy(pc, device);
	}

	v = (1 << 30); /* Start of Transaction */
	v |= (1 << 29); /* Read Transaction */
	v |= (1 << 17); /* Turnaround */
	if (pc->dev->id.revision < 10)
		v |= (u32)device << 22;
	v |= (u32)address << 18;
	pcicore_write32(pc, mdio_data, v);
	/* Wait for the device to complete the transaction */
	udelay(10);
	for (i = 0; i < max_retries; i++) {
		v = pcicore_read32(pc, mdio_control);
		if (v & 0x100 /* Trans complete */) {
			udelay(10);
			ret = pcicore_read32(pc, mdio_data);
			break;
		}
		msleep(1);
	}
	pcicore_write32(pc, mdio_control, 0);
	return ret;
}