Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751821AbdLFMTc (ORCPT ); Wed, 6 Dec 2017 07:19:32 -0500 Received: from mail-lf0-f67.google.com ([209.85.215.67]:44561 "EHLO mail-lf0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750989AbdLFMT2 (ORCPT ); Wed, 6 Dec 2017 07:19:28 -0500 X-Google-Smtp-Source: AGs4zMYUTaUsNa+W+UxkQj2O6dJTFQ/XU+lUTINN8pPzjrVdAmyZbP+NQ5NcKscoKeZiQgWOp43y7A== Subject: Re: [PATCH 4/7 v2] net: ethernet: i825xx: Fix platform_get_irq's error checking To: David Miller , arvind.yadav.cs@gmail.com Cc: wg@grandegger.com, mkl@pengutronix.de, michal.simek@xilinx.com, opendmb@gmail.com, f.fainelli@gmail.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org References: <1512409703-20881-5-git-send-email-arvind.yadav.cs@gmail.com> <20171204.132556.1601454745789376393.davem@davemloft.net> <39363858-995c-eea4-070e-b21a7ac49bec@gmail.com> <20171205.104947.121188625730183933.davem@davemloft.net> From: Sergei Shtylyov Organization: Cogent Embedded Message-ID: Date: Wed, 6 Dec 2017 15:19:24 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <20171205.104947.121188625730183933.davem@davemloft.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-MW Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1816 Lines: 51 On 12/05/2017 06:49 PM, David Miller wrote: >>> From: Arvind Yadav >>> Date: Mon, 4 Dec 2017 23:18:20 +0530 >>> >>>> @@ -120,9 +120,10 @@ static int sni_82596_probe(struct platform_device >>>> *dev) >>>> netdevice->dev_addr[5] = readb(eth_addr + 0x06); >>>> iounmap(eth_addr); >>>> - if (!netdevice->irq) { >>>> + if (netdevice->irq <= 0) { >>>> printk(KERN_ERR "%s: IRQ not found for i82596 at 0x%lx\n", >>>> __FILE__, netdevice->base_addr); >>>> + retval = netdevice->irq ? netdevice->irq : -ENODEV; >>>> goto probe_failed; >>>> } >>> Ok, thinking about this some more... >>> >>> It is impossible to use platform_get_irq() without every single call >>> site having this funny: >>> >>> ret = val ? val : -ENODEV; >>> >>> sequence. >>> >>> This is unnecessary duplication and it is also error prone, so I >>> really think this logic belongs in platform_get_irq() itself. It can >>> convert '0' to -ENODEV and that way we need no special logic in the >>> callers at all. >> platform_get_irq() will return 0 only for sparc, If sparc initialize >> platform >> data irq[PROMINTR_MAX] as zero. Otherwise platform_get_irq() will >> never return >> 0. It will return either IRQ number or error (as negative number). But >> I am getting >> review comment by reviewer/maintainer in other subsystem to add check >> for >> zero. So I have done same changes here. Please correct me if i am >> wrong. > > If you make the change that I suggest, you instead can check for I assume such change is needed only for the SPARC-specific section of platform_get_irq()? > '-ENODEV' to mean no IRQ. No specific error check is needed, just irq < 0 check should be enough... Also, looking at platform_get_irq(), -ENXIO should be returned in this case. MBR, Sergei