From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752212AbdGCE1M (ORCPT ); Mon, 3 Jul 2017 00:27:12 -0400 Received: from lelnx194.ext.ti.com ([198.47.27.80]:42739 "EHLO lelnx194.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750793AbdGCE1J (ORCPT ); Mon, 3 Jul 2017 00:27:09 -0400 Subject: Re: [linux-next][PATCH] usb: dwc3: omap: remove IRQ_NOAUTOEN used with shared irq To: "Strashko, Grygorii" , Tony Lindgren CC: "GregKroah-Hartmangregkh@linuxfoundation.org" , Felipe Balbi , "linux-omap@vger.kernel.org" , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "Nori, Sekhar" References: <20170628233131.19114-1-grygorii.strashko@ti.com> <463ea19c-dc60-5926-56b4-0f10d2e23e94@ti.com> <20170629060353.GE3730@atomide.com> From: Vignesh R Message-ID: Date: Mon, 3 Jul 2017 09:57:17 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Saturday 01 July 2017 01:04 AM, Strashko, Grygorii wrote: > > > On 06/29/2017 01:03 AM, Tony Lindgren wrote: >> * Vignesh R [170628 21:21]: >>> >>> >>> On Thursday 29 June 2017 05:01 AM, Strashko, Grygorii wrote: >>>> IRQ_NOAUTOEN can't be used with shared IRQs and Kernel now will triggers >>>> warning if it happns, since commit 04c848d39879 ("genirq: Warn when >>>> IRQ_NOAUTOEN is used with shared interrupts"). And this is the case for >>>> OMAP DWC 3 driver. >>>> >>>> Hence, remove IRQ_NOAUTOEN flag and instead call disable_irq() before >>>> disabling PM runtime in probe error path handling. >>> >>> Or, how about requesting the irq at the end of probe after extcon >>> registration? >> >> Hmm yeah, what prevents the issue that we tried to fix with commit >> 12a7f17fac5b ("usb: dwc3: omap: fix race of pm runtime with irq handler >> in probe")? > > No, I think. There should be the disable_irq() call any way > before pm_runtime_put_sync(dev);| pm_runtime_disable(dev); - > once IRQ is requested driver can't know if IRQ handler is running now or not > unless it will call disable_irq()/free_irq(). > > But, I've also thought about moving request_irq() down (seems > it can be moved even after of_platform_populate()). > looks like it can be separate patch. > commit 12a7f17fac5b says PM runtime can race with IRQ handler when deferred probing happening due to extcon, therefore IRQ_NOAUTOEN was set and disable_irq() call was added. If IRQ handler registration is moved to a place after of_platform_populate(), then we can be sure that extcon is registered and there wont be any deferred probe or race with irq handler and PM runtime. Would disable_irq() still be needed then? > >>>> Fixes: 12a7f17fac5b ("usb: dwc3: omap: fix race of pm runtime with...") >>>> Signed-off-by: Grygorii Strashko >>>> --- >>>> drivers/usb/dwc3/dwc3-omap.c | 3 +-- >>>> 1 file changed, 1 insertion(+), 2 deletions(-) >>>> >>>> diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c >>>> index 9892650..cd9bef5 100644 >>>> --- a/drivers/usb/dwc3/dwc3-omap.c >>>> +++ b/drivers/usb/dwc3/dwc3-omap.c >>>> @@ -512,7 +512,6 @@ static int dwc3_omap_probe(struct platform_device *pdev) >>>> >>>> /* check the DMA Status */ >>>> reg = dwc3_omap_readl(omap->base, USBOTGSS_SYSCONFIG); >>>> - irq_set_status_flags(omap->irq, IRQ_NOAUTOEN); >>>> ret = devm_request_threaded_irq(dev, omap->irq, dwc3_omap_interrupt, >>>> dwc3_omap_interrupt_thread, IRQF_SHARED, >>>> "dwc3-omap", omap); >>>> @@ -533,10 +532,10 @@ static int dwc3_omap_probe(struct platform_device *pdev) >>>> } >>>> >>>> dwc3_omap_enable_irqs(omap); >>>> - enable_irq(omap->irq); >>>> return 0; >>>> >>>> err1: >>>> + disable_irq(omap->irq); >>>> pm_runtime_put_sync(dev); >>>> pm_runtime_disable(dev); >>>> > -- Regards Vignesh