static int img_pwm_probe()

in pwm-img.c [238:324]

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

static int img_pwm_probe(struct platform_device *pdev)
{
	int ret;
	u64 val;
	unsigned long clk_rate;
	struct img_pwm_chip *pwm;
	const struct of_device_id *of_dev_id;

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

	pwm->dev = &pdev->dev;

	pwm->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(pwm->base))
		return PTR_ERR(pwm->base);

	of_dev_id = of_match_device(img_pwm_of_match, &pdev->dev);
	if (!of_dev_id)
		return -ENODEV;
	pwm->data = of_dev_id->data;

	pwm->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
							   "img,cr-periph");
	if (IS_ERR(pwm->periph_regs))
		return PTR_ERR(pwm->periph_regs);

	pwm->sys_clk = devm_clk_get(&pdev->dev, "sys");
	if (IS_ERR(pwm->sys_clk)) {
		dev_err(&pdev->dev, "failed to get system clock\n");
		return PTR_ERR(pwm->sys_clk);
	}

	pwm->pwm_clk = devm_clk_get(&pdev->dev, "pwm");
	if (IS_ERR(pwm->pwm_clk)) {
		dev_err(&pdev->dev, "failed to get pwm clock\n");
		return PTR_ERR(pwm->pwm_clk);
	}

	platform_set_drvdata(pdev, pwm);

	pm_runtime_set_autosuspend_delay(&pdev->dev, IMG_PWM_PM_TIMEOUT);
	pm_runtime_use_autosuspend(&pdev->dev);
	pm_runtime_enable(&pdev->dev);
	if (!pm_runtime_enabled(&pdev->dev)) {
		ret = img_pwm_runtime_resume(&pdev->dev);
		if (ret)
			goto err_pm_disable;
	}

	clk_rate = clk_get_rate(pwm->pwm_clk);
	if (!clk_rate) {
		dev_err(&pdev->dev, "pwm clock has no frequency\n");
		ret = -EINVAL;
		goto err_suspend;
	}

	/* The maximum input clock divider is 512 */
	val = (u64)NSEC_PER_SEC * 512 * pwm->data->max_timebase;
	do_div(val, clk_rate);
	pwm->max_period_ns = val;

	val = (u64)NSEC_PER_SEC * MIN_TMBASE_STEPS;
	do_div(val, clk_rate);
	pwm->min_period_ns = val;

	pwm->chip.dev = &pdev->dev;
	pwm->chip.ops = &img_pwm_ops;
	pwm->chip.npwm = IMG_PWM_NPWM;

	ret = pwmchip_add(&pwm->chip);
	if (ret < 0) {
		dev_err(&pdev->dev, "pwmchip_add failed: %d\n", ret);
		goto err_suspend;
	}

	return 0;

err_suspend:
	if (!pm_runtime_enabled(&pdev->dev))
		img_pwm_runtime_suspend(&pdev->dev);
err_pm_disable:
	pm_runtime_disable(&pdev->dev);
	pm_runtime_dont_use_autosuspend(&pdev->dev);
	return ret;
}