static int fsi_master_gpio_probe()

in fsi-master-gpio.c [771:866]

• 76 lines of code
• 9 McCabe index (conditional complexity)

static int fsi_master_gpio_probe(struct platform_device *pdev)
{
	struct fsi_master_gpio *master;
	struct gpio_desc *gpio;
	int rc;

	master = kzalloc(sizeof(*master), GFP_KERNEL);
	if (!master)
		return -ENOMEM;

	master->dev = &pdev->dev;
	master->master.dev.parent = master->dev;
	master->master.dev.of_node = of_node_get(dev_of_node(master->dev));
	master->master.dev.release = fsi_master_gpio_release;
	master->last_addr = LAST_ADDR_INVALID;

	gpio = devm_gpiod_get(&pdev->dev, "clock", 0);
	if (IS_ERR(gpio)) {
		dev_err(&pdev->dev, "failed to get clock gpio\n");
		rc = PTR_ERR(gpio);
		goto err_free;
	}
	master->gpio_clk = gpio;

	gpio = devm_gpiod_get(&pdev->dev, "data", 0);
	if (IS_ERR(gpio)) {
		dev_err(&pdev->dev, "failed to get data gpio\n");
		rc = PTR_ERR(gpio);
		goto err_free;
	}
	master->gpio_data = gpio;

	/* Optional GPIOs */
	gpio = devm_gpiod_get_optional(&pdev->dev, "trans", 0);
	if (IS_ERR(gpio)) {
		dev_err(&pdev->dev, "failed to get trans gpio\n");
		rc = PTR_ERR(gpio);
		goto err_free;
	}
	master->gpio_trans = gpio;

	gpio = devm_gpiod_get_optional(&pdev->dev, "enable", 0);
	if (IS_ERR(gpio)) {
		dev_err(&pdev->dev, "failed to get enable gpio\n");
		rc = PTR_ERR(gpio);
		goto err_free;
	}
	master->gpio_enable = gpio;

	gpio = devm_gpiod_get_optional(&pdev->dev, "mux", 0);
	if (IS_ERR(gpio)) {
		dev_err(&pdev->dev, "failed to get mux gpio\n");
		rc = PTR_ERR(gpio);
		goto err_free;
	}
	master->gpio_mux = gpio;

	/*
	 * Check if GPIO block is slow enought that no extra delays
	 * are necessary. This improves performance on ast2500 by
	 * an order of magnitude.
	 */
	master->no_delays = device_property_present(&pdev->dev, "no-gpio-delays");

	/* Default FSI command delays */
	master->t_send_delay = FSI_SEND_DELAY_CLOCKS;
	master->t_echo_delay = FSI_ECHO_DELAY_CLOCKS;

	master->master.n_links = 1;
	master->master.flags = FSI_MASTER_FLAG_SWCLOCK;
	master->master.read = fsi_master_gpio_read;
	master->master.write = fsi_master_gpio_write;
	master->master.term = fsi_master_gpio_term;
	master->master.send_break = fsi_master_gpio_break;
	master->master.link_enable = fsi_master_gpio_link_enable;
	master->master.link_config = fsi_master_gpio_link_config;
	platform_set_drvdata(pdev, master);
	mutex_init(&master->cmd_lock);

	fsi_master_gpio_init(master);

	rc = device_create_file(&pdev->dev, &dev_attr_external_mode);
	if (rc)
		goto err_free;

	rc = fsi_master_register(&master->master);
	if (rc) {
		device_remove_file(&pdev->dev, &dev_attr_external_mode);
		put_device(&master->master.dev);
		return rc;
	}
	return 0;
 err_free:
	kfree(master);
	return rc;
}