static int configure_1394a_enhancements()

in ohci.c [2188:2237]

• 39 lines of code
• 10 McCabe index (conditional complexity)

static int configure_1394a_enhancements(struct fw_ohci *ohci)
{
	bool enable_1394a;
	int ret, clear, set, offset;

	/* Check if the driver should configure link and PHY. */
	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
	      OHCI1394_HCControl_programPhyEnable))
		return 0;

	/* Paranoia: check whether the PHY supports 1394a, too. */
	enable_1394a = false;
	ret = read_phy_reg(ohci, 2);
	if (ret < 0)
		return ret;
	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
		ret = read_paged_phy_reg(ohci, 1, 8);
		if (ret < 0)
			return ret;
		if (ret >= 1)
			enable_1394a = true;
	}

	if (ohci->quirks & QUIRK_NO_1394A)
		enable_1394a = false;

	/* Configure PHY and link consistently. */
	if (enable_1394a) {
		clear = 0;
		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
	} else {
		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
		set = 0;
	}
	ret = update_phy_reg(ohci, 5, clear, set);
	if (ret < 0)
		return ret;

	if (enable_1394a)
		offset = OHCI1394_HCControlSet;
	else
		offset = OHCI1394_HCControlClear;
	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);

	/* Clean up: configuration has been taken care of. */
	reg_write(ohci, OHCI1394_HCControlClear,
		  OHCI1394_HCControl_programPhyEnable);

	return 0;
}