static int rtc_probe()

in rtc-vr41xx.c [258:351]

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

static int rtc_probe(struct platform_device *pdev)
{
	struct resource *res;
	struct rtc_device *rtc;
	int retval;

	if (pdev->num_resources != 4)
		return -EBUSY;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return -EBUSY;

	rtc1_base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
	if (!rtc1_base)
		return -EBUSY;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	if (!res) {
		retval = -EBUSY;
		goto err_rtc1_iounmap;
	}

	rtc2_base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
	if (!rtc2_base) {
		retval = -EBUSY;
		goto err_rtc1_iounmap;
	}

	rtc = devm_rtc_allocate_device(&pdev->dev);
	if (IS_ERR(rtc)) {
		retval = PTR_ERR(rtc);
		goto err_iounmap_all;
	}

	rtc->ops = &vr41xx_rtc_ops;

	/* 48-bit counter at 32.768 kHz */
	rtc->range_max = (1ULL << 33) - 1;
	rtc->max_user_freq = MAX_PERIODIC_RATE;

	spin_lock_irq(&rtc_lock);

	rtc1_write(ECMPLREG, 0);
	rtc1_write(ECMPMREG, 0);
	rtc1_write(ECMPHREG, 0);
	rtc1_write(RTCL1LREG, 0);
	rtc1_write(RTCL1HREG, 0);

	spin_unlock_irq(&rtc_lock);

	aie_irq = platform_get_irq(pdev, 0);
	if (aie_irq <= 0) {
		retval = -EBUSY;
		goto err_iounmap_all;
	}

	retval = devm_request_irq(&pdev->dev, aie_irq, elapsedtime_interrupt, 0,
				"elapsed_time", pdev);
	if (retval < 0)
		goto err_iounmap_all;

	pie_irq = platform_get_irq(pdev, 1);
	if (pie_irq <= 0) {
		retval = -EBUSY;
		goto err_iounmap_all;
	}

	retval = devm_request_irq(&pdev->dev, pie_irq, rtclong1_interrupt, 0,
				"rtclong1", pdev);
	if (retval < 0)
		goto err_iounmap_all;

	platform_set_drvdata(pdev, rtc);

	disable_irq(aie_irq);
	disable_irq(pie_irq);

	dev_info(&pdev->dev, "Real Time Clock of NEC VR4100 series\n");

	retval = devm_rtc_register_device(rtc);
	if (retval)
		goto err_iounmap_all;

	return 0;

err_iounmap_all:
	rtc2_base = NULL;

err_rtc1_iounmap:
	rtc1_base = NULL;

	return retval;
}