static int icm_reset_phy_port()

in icm.c [1843:1909]

• 50 lines of code
• 12 McCabe index (conditional complexity)

static int icm_reset_phy_port(struct tb *tb, int phy_port)
{
	struct icm *icm = tb_priv(tb);
	u32 state0, state1;
	int port0, port1;
	u32 val0, val1;
	int ret;

	if (!icm->upstream_port)
		return 0;

	if (phy_port) {
		port0 = 3;
		port1 = 4;
	} else {
		port0 = 1;
		port1 = 2;
	}

	/*
	 * Read link status of both null ports belonging to a single
	 * physical port.
	 */
	ret = pcie2cio_read(icm, TB_CFG_PORT, port0, PHY_PORT_CS1, &val0);
	if (ret)
		return ret;
	ret = pcie2cio_read(icm, TB_CFG_PORT, port1, PHY_PORT_CS1, &val1);
	if (ret)
		return ret;

	state0 = val0 & PHY_PORT_CS1_LINK_STATE_MASK;
	state0 >>= PHY_PORT_CS1_LINK_STATE_SHIFT;
	state1 = val1 & PHY_PORT_CS1_LINK_STATE_MASK;
	state1 >>= PHY_PORT_CS1_LINK_STATE_SHIFT;

	/* If they are both up we need to reset them now */
	if (state0 != TB_PORT_UP || state1 != TB_PORT_UP)
		return 0;

	val0 |= PHY_PORT_CS1_LINK_DISABLE;
	ret = pcie2cio_write(icm, TB_CFG_PORT, port0, PHY_PORT_CS1, val0);
	if (ret)
		return ret;

	val1 |= PHY_PORT_CS1_LINK_DISABLE;
	ret = pcie2cio_write(icm, TB_CFG_PORT, port1, PHY_PORT_CS1, val1);
	if (ret)
		return ret;

	/* Wait a bit and then re-enable both ports */
	usleep_range(10, 100);

	ret = pcie2cio_read(icm, TB_CFG_PORT, port0, PHY_PORT_CS1, &val0);
	if (ret)
		return ret;
	ret = pcie2cio_read(icm, TB_CFG_PORT, port1, PHY_PORT_CS1, &val1);
	if (ret)
		return ret;

	val0 &= ~PHY_PORT_CS1_LINK_DISABLE;
	ret = pcie2cio_write(icm, TB_CFG_PORT, port0, PHY_PORT_CS1, val0);
	if (ret)
		return ret;

	val1 &= ~PHY_PORT_CS1_LINK_DISABLE;
	return pcie2cio_write(icm, TB_CFG_PORT, port1, PHY_PORT_CS1, val1);
}