From mboxrd@z Thu Jan 1 00:00:00 1970 From: lee.jones@linaro.org (Lee Jones) Date: Wed, 18 Feb 2015 12:08:44 +0000 Subject: [PATCH v5 1/6] mfd: fsl imx25 Touchscreen ADC driver In-Reply-To: References: <1422108103-15052-1-git-send-email-mpa@pengutronix.de> <1422108103-15052-2-git-send-email-mpa@pengutronix.de> <20150216133829.GG14545@x1> <20150218080156.GA5781@x1> Message-ID: <20150218120844.GC22296@x1> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, 18 Feb 2015, Fabio Estevam wrote: > On Wed, Feb 18, 2015 at 6:01 AM, Lee Jones wrote: > > On Tue, 17 Feb 2015, Fabio Estevam wrote: > > > >> On Mon, Feb 16, 2015 at 11:38 AM, Lee Jones wrote: > >> > >> >> +static int mx25_tsadc_setup_irq(struct platform_device *pdev, > >> >> + struct mx25_tsadc *tsadc) > >> >> +{ > >> >> + struct device *dev = &pdev->dev; > >> >> + struct device_node *np = dev->of_node; > >> >> + int irq; > >> >> + > >> >> + irq = platform_get_irq(pdev, 0); > >> >> + if (irq < 0) { > >> > > >> > What if 0 is returned? > >> > >> Then imx25.dtsi would be passing irq=0 for the ADC, which would be > >> totally wrong. > > > > Exactly, so it should be <=. > > imx25.dtsi passes interrupts = <46>; for the touch screen controller, > so the irq number will never be zero. It doesn't matter what happens to be passed at the moment. The correct thing to do is enforce correct/full error checking. Yes <0 is an error, but so is =0, so encompass it in the checks. -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org ? Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog