static int zynq_gpio_probe()

in gpio-zynq.c [893:999]

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

static int zynq_gpio_probe(struct platform_device *pdev)
{
	int ret, bank_num;
	struct zynq_gpio *gpio;
	struct gpio_chip *chip;
	struct gpio_irq_chip *girq;
	const struct of_device_id *match;

	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
	if (!gpio)
		return -ENOMEM;

	match = of_match_node(zynq_gpio_of_match, pdev->dev.of_node);
	if (!match) {
		dev_err(&pdev->dev, "of_match_node() failed\n");
		return -EINVAL;
	}
	gpio->p_data = match->data;
	platform_set_drvdata(pdev, gpio);

	gpio->base_addr = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(gpio->base_addr))
		return PTR_ERR(gpio->base_addr);

	gpio->irq = platform_get_irq(pdev, 0);
	if (gpio->irq < 0)
		return gpio->irq;

	/* configure the gpio chip */
	chip = &gpio->chip;
	chip->label = gpio->p_data->label;
	chip->owner = THIS_MODULE;
	chip->parent = &pdev->dev;
	chip->get = zynq_gpio_get_value;
	chip->set = zynq_gpio_set_value;
	chip->request = zynq_gpio_request;
	chip->free = zynq_gpio_free;
	chip->direction_input = zynq_gpio_dir_in;
	chip->direction_output = zynq_gpio_dir_out;
	chip->get_direction = zynq_gpio_get_direction;
	chip->base = of_alias_get_id(pdev->dev.of_node, "gpio");
	chip->ngpio = gpio->p_data->ngpio;

	/* Retrieve GPIO clock */
	gpio->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(gpio->clk))
		return dev_err_probe(&pdev->dev, PTR_ERR(gpio->clk), "input clock not found.\n");

	ret = clk_prepare_enable(gpio->clk);
	if (ret) {
		dev_err(&pdev->dev, "Unable to enable clock.\n");
		return ret;
	}

	spin_lock_init(&gpio->dirlock);

	pm_runtime_set_active(&pdev->dev);
	pm_runtime_enable(&pdev->dev);
	ret = pm_runtime_resume_and_get(&pdev->dev);
	if (ret < 0)
		goto err_pm_dis;

	/* disable interrupts for all banks */
	for (bank_num = 0; bank_num < gpio->p_data->max_bank; bank_num++) {
		writel_relaxed(ZYNQ_GPIO_IXR_DISABLE_ALL, gpio->base_addr +
			       ZYNQ_GPIO_INTDIS_OFFSET(bank_num));
		if (gpio->p_data->quirks & GPIO_QUIRK_VERSAL)
			bank_num = bank_num + VERSAL_UNUSED_BANKS;
	}

	/* Set up the GPIO irqchip */
	girq = &chip->irq;
	girq->chip = &zynq_gpio_edge_irqchip;
	girq->parent_handler = zynq_gpio_irqhandler;
	girq->num_parents = 1;
	girq->parents = devm_kcalloc(&pdev->dev, 1,
				     sizeof(*girq->parents),
				     GFP_KERNEL);
	if (!girq->parents) {
		ret = -ENOMEM;
		goto err_pm_put;
	}
	girq->parents[0] = gpio->irq;
	girq->default_type = IRQ_TYPE_NONE;
	girq->handler = handle_level_irq;

	/* report a bug if gpio chip registration fails */
	ret = gpiochip_add_data(chip, gpio);
	if (ret) {
		dev_err(&pdev->dev, "Failed to add gpio chip\n");
		goto err_pm_put;
	}

	irq_set_status_flags(gpio->irq, IRQ_DISABLE_UNLAZY);
	device_init_wakeup(&pdev->dev, 1);
	pm_runtime_put(&pdev->dev);

	return 0;

err_pm_put:
	pm_runtime_put(&pdev->dev);
err_pm_dis:
	pm_runtime_disable(&pdev->dev);
	clk_disable_unprepare(gpio->clk);

	return ret;
}