[PATCH v7 3/3] iio: adc: add support for Allwinner SoCs ADC

[Julia Lawall]

I haven't checked the complete context, but it seems that *irq that is
tested on line 431 is unsigned.

julia

On Thu, 3 Nov 2016, kbuild test robot wrote:

> Hi Quentin,
>
> [auto build test WARNING on next-20161028]
> [cannot apply to iio/togreg input/next linus/master v4.9-rc3 v4.9-rc2 v4.9-rc1 v4.9-rc3]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url:    https://github.com/0day-ci/linux/commits/Quentin-Schulz/add-support-for-Allwinner-SoCs-ADC/20161103-182828
> :::::: branch date: 2 hours ago
> :::::: commit date: 2 hours ago
>
> >> drivers/iio/adc/sun4i-gpadc-iio.c:431:5-9: WARNING: Unsigned expression compared with zero: * irq < 0
>
> git remote add linux-review https://github.com/0day-ci/linux
> git remote update linux-review
> git checkout 0068e4d1386fff54958ef3b8b304239982feaa8a
> vim +431 drivers/iio/adc/sun4i-gpadc-iio.c
>
> 0068e4d1 Quentin Schulz 2016-11-03  415
> 0068e4d1 Quentin Schulz 2016-11-03  416  	/*
> 0068e4d1 Quentin Schulz 2016-11-03  417  	 * Once the interrupt is activated, the IP continuously performs
> 0068e4d1 Quentin Schulz 2016-11-03  418  	 * conversions thus throws interrupts. The interrupt is activated right
> 0068e4d1 Quentin Schulz 2016-11-03  419  	 * after being requested but we want to control when these interrupts
> 0068e4d1 Quentin Schulz 2016-11-03  420  	 * occur thus we disable it right after being requested. However, an
> 0068e4d1 Quentin Schulz 2016-11-03  421  	 * interrupt might occur between these two instructions and we have to
> 0068e4d1 Quentin Schulz 2016-11-03  422  	 * make sure that does not happen, by using atomic flags. We set the
> 0068e4d1 Quentin Schulz 2016-11-03  423  	 * flag before requesting the interrupt and unset it right after
> 0068e4d1 Quentin Schulz 2016-11-03  424  	 * disabling the interrupt. When an interrupt occurs between these two
> 0068e4d1 Quentin Schulz 2016-11-03  425  	 * instructions, reading the atomic flag will tell us to ignore the
> 0068e4d1 Quentin Schulz 2016-11-03  426  	 * interrupt.
> 0068e4d1 Quentin Schulz 2016-11-03  427  	 */
> 0068e4d1 Quentin Schulz 2016-11-03  428  	atomic_set(atomic, 1);
> 0068e4d1 Quentin Schulz 2016-11-03  429
> 0068e4d1 Quentin Schulz 2016-11-03  430  	*irq = platform_get_irq_byname(pdev, name);
> 0068e4d1 Quentin Schulz 2016-11-03 @431  	if (*irq < 0) {
> 0068e4d1 Quentin Schulz 2016-11-03  432  		dev_err(&pdev->dev, "no %s interrupt registered\n", name);
> 0068e4d1 Quentin Schulz 2016-11-03  433  		return *irq;
> 0068e4d1 Quentin Schulz 2016-11-03  434  	}
> 0068e4d1 Quentin Schulz 2016-11-03  435
> 0068e4d1 Quentin Schulz 2016-11-03  436  	*irq = regmap_irq_get_virq(mfd_dev->regmap_irqc, *irq);
> 0068e4d1 Quentin Schulz 2016-11-03  437  	ret = devm_request_any_context_irq(&pdev->dev, *irq, handler, 0,
> 0068e4d1 Quentin Schulz 2016-11-03  438  					   devname, info);
> 0068e4d1 Quentin Schulz 2016-11-03  439  	if (ret < 0) {
>
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