From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Crispin Subject: Re: [PATCH] mfd: mt6397: irq domain should initialize before mfd_add_devices() Date: Thu, 31 Mar 2016 11:08:32 +0200 Message-ID: <56FCE910.8030100@openwrt.org> References: <1459322708-21363-1-git-send-email-henryc.chen@mediatek.com> <56FB99DB.6010901@openwrt.org> <1459388452.18284.2.camel@mtksdaap41> <1459391533.21870.15.camel@mtksdaap41> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1459391533.21870.15.camel@mtksdaap41> Sender: linux-kernel-owner@vger.kernel.org To: Yingjoe Chen , Henry Chen Cc: Sascha Hauer , linux-kernel@vger.kernel.org, Flora Fu , linux-mediatek@lists.infradead.org, Matthias Brugger , Lee Jones , linux-arm-kernel@lists.infradead.org List-Id: linux-mediatek@lists.infradead.org On 31/03/2016 04:32, Yingjoe Chen wrote: > On Thu, 2016-03-31 at 09:40 +0800, Henry Chen wrote: >> On Wed, 2016-03-30 at 11:18 +0200, John Crispin wrote: >>> Hi, >>> >>> small nitpick inline >>> >>> On 30/03/2016 09:25, Henry Chen wrote: >>>> Some sub driver like RTC module need irq domain from parent to create >>>> irq mapping when driver initialize. so move mt6397_irq_init() before >>>> mfd_add_devices(). >>>> >>>> Signed-off-by: Henry Chen >>>> --- >>>> This patch fixed the below warning based on "Linux kernel v4.6-rc1" >>>> WARNING: CPU: 1 PID: 132 at kernel/mediatek/kernel/irq/irqdomain.c:471 >>>> irq_create_mapping+0xc4/0xd0 >>>> --- >>>> drivers/mfd/mt6397-core.c | 37 ++++++++++++++++++++++--------------- >>>> 1 file changed, 22 insertions(+), 15 deletions(-) >>>> >>>> diff --git a/drivers/mfd/mt6397-core.c b/drivers/mfd/mt6397-core.c >>>> index 8e8d932..a879223 100644 >>>> --- a/drivers/mfd/mt6397-core.c >>>> +++ b/drivers/mfd/mt6397-core.c >>>> @@ -270,22 +270,36 @@ static int mt6397_probe(struct platform_device *pdev) >>>> goto fail_irq; >>>> } >>>> >>>> + pmic->irq = platform_get_irq(pdev, 0); >>>> + >>>> switch (id & 0xff) { >>>> case MT6323_CID_CODE: >>>> - pmic->int_con[0] = MT6323_INT_CON0; >>>> - pmic->int_con[1] = MT6323_INT_CON1; >>>> - pmic->int_status[0] = MT6323_INT_STATUS0; >>>> - pmic->int_status[1] = MT6323_INT_STATUS1; >>>> + if (pmic->irq > 0) { >>> >>> should this not be >>> >>> if (pmic->irq >= 0) { >>> >>> i think the code before your patch was wrong as linux irqs start with 0. >>> >>> John >> Hi John, >> >> Thanks, I will modify this. > > Linux irq start from 1, 0 is invalid. I can't find the document saying > this now, but you could see this from irq_create_mapping() in > kernel/irq/irqdomain.c > > I think the code should have check return from platform_get_irq and > handle -EPROBE_DEFER, but maybe it should be another patch? > > BTW, in this function, it is possible that pmic->irq_domain will be NULL > in fail_irq error handling. We should check before calling > irq_domain_remove. > > Joe.C > Hi, looking at http://lxr.free-electrons.com/source/drivers/base/platform.c#L87 there is a check in line #100 ret >= 0 checking the return value of pmic->irq = platform_get_irq(pdev, 0); should follow the same pattern i think .. unless i have a thinko and am reading the code wrong. John