static int tacoma_cabled_fsi_fixup()

in fsi-master-aspeed.c [486:531]

• 29 lines of code
• 8 McCabe index (conditional complexity)

static int tacoma_cabled_fsi_fixup(struct device *dev)
{
	struct gpio_desc *routing_gpio, *mux_gpio;
	int gpio;

	/*
	 * The routing GPIO is a jumper indicating we should mux for the
	 * externally connected FSI cable.
	 */
	routing_gpio = devm_gpiod_get_optional(dev, "fsi-routing",
			GPIOD_IN | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
	if (IS_ERR(routing_gpio))
		return PTR_ERR(routing_gpio);
	if (!routing_gpio)
		return 0;

	mux_gpio = devm_gpiod_get_optional(dev, "fsi-mux", GPIOD_ASIS);
	if (IS_ERR(mux_gpio))
		return PTR_ERR(mux_gpio);
	if (!mux_gpio)
		return 0;

	gpio = gpiod_get_value(routing_gpio);
	if (gpio < 0)
		return gpio;

	/* If the routing GPIO is high we should set the mux to low. */
	if (gpio) {
		/*
		 * Cable signal integrity means we should run the bus
		 * slightly slower. Do not override if a kernel param
		 * has already overridden.
		 */
		if (aspeed_fsi_divisor == FSI_DIVISOR_DEFAULT)
			aspeed_fsi_divisor = FSI_DIVISOR_CABLED;

		gpiod_direction_output(mux_gpio, 0);
		dev_info(dev, "FSI configured for external cable\n");
	} else {
		gpiod_direction_output(mux_gpio, 1);
	}

	devm_gpiod_put(dev, routing_gpio);

	return 0;
}