Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757222AbaKTVsp (ORCPT ); Thu, 20 Nov 2014 16:48:45 -0500 Received: from metis.ext.pengutronix.de ([92.198.50.35]:38737 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757161AbaKTVsm (ORCPT ); Thu, 20 Nov 2014 16:48:42 -0500 Date: Thu, 20 Nov 2014 22:48:38 +0100 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= To: Grygorii Strashko Cc: Wolfram Sang , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Sekhar Nori , Kevin Hilman , Santosh Shilimkar , Murali Karicheri Subject: Re: [1/5] i2c: i2c-davinci: switch to use platform_get_irq Message-ID: <20141120214838.GA346@pengutronix.de> References: <1416477788-5544-2-git-send-email-grygorii.strashko@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1416477788-5544-2-git-send-email-grygorii.strashko@ti.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Grygorii, On Thu, Nov 20, 2014 at 12:03:04PM +0200, Grygorii Strashko wrote: > Switch Davinci I2C driver to use platform_get_irq(), because > - it is not recommened to use > platform_get_resource(pdev, IORESOURCE_IRQ, ..) for requesting IRQ's > resources any more, as they can be not ready yet in case of DT-booting. > - it makes code simpler > > CC: Sekhar Nori > CC: Kevin Hilman > CC: Santosh Shilimkar > CC: Murali Karicheri > Signed-off-by: Grygorii Strashko > --- > drivers/i2c/busses/i2c-davinci.c | 14 +++++++------- > 1 file changed, 7 insertions(+), 7 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c > index 4d96147..9bbfb8f 100644 > --- a/drivers/i2c/busses/i2c-davinci.c > +++ b/drivers/i2c/busses/i2c-davinci.c > @@ -640,13 +640,13 @@ static int davinci_i2c_probe(struct platform_device *pdev) > { > struct davinci_i2c_dev *dev; > struct i2c_adapter *adap; > - struct resource *mem, *irq; > - int r; > + struct resource *mem; > + int r, irq; > > - irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); > - if (!irq) { > - dev_err(&pdev->dev, "no irq resource?\n"); > - return -ENODEV; > + irq = platform_get_irq(pdev, 0); One bad thing about platform_get_irq is its unusual handling of irq=0. I'm pretty sure you don't want to use this value, so adding something like: if (!irq) irq = -ENXIO would be welcome because the usual value for "invalid irq" is 0 and not -ESOMETHING. platform_get_irq is one of the very few functions that don't adhere to this convention. With handling <= 0 as error your code is immune to changes in this area. Although I notice that platform_get_irq got worse in this respect to handle -EPROBE_DEFER. hmm. Apart from your change I wonder if platform_get_irq should handle of_irq_get returning 0 as an error. > + if (irq < 0) { > + dev_err(&pdev->dev, "can't get irq resource ret=%d\n", irq); Please don't print an error if irq=-EPROBE_DEFER. > + return irq; > } -- Pengutronix e.K. | Uwe Kleine-K?nig | Industrial Linux Solutions | http://www.pengutronix.de/ | -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/