From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Grygorii.Strashko@linaro.org" Subject: Re: [PATCH v2] leds: fix hibernation on arm when gpio-led used with CPU led trigger Date: Tue, 24 Feb 2015 18:12:19 +0200 Message-ID: <54ECA2E3.8060401@linaro.org> References: <1423147024-4744-1-git-send-email-grygorii.strashko@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-lb0-f181.google.com ([209.85.217.181]:40532 "EHLO mail-lb0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752350AbbBXQMW (ORCPT ); Tue, 24 Feb 2015 11:12:22 -0500 Received: by lbdu10 with SMTP id u10so25906154lbd.7 for ; Tue, 24 Feb 2015 08:12:21 -0800 (PST) In-Reply-To: <1423147024-4744-1-git-send-email-grygorii.strashko@linaro.org> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Bryan Wu , Richard Purdie , linux-leds@vger.kernel.org Cc: sumit.semwal@linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, "Menon, Nishanth" , Kevin Hilman , "Rafael J. Wysocki" Hi Bryan, all, On 02/05/2015 04:37 PM, grygorii.strashko@linaro.org wrote: > From: Grygorii Strashko > > Setting a dev_pm_ops suspend/resume pair of callbacks but not a set of > hibernation callbacks means those pm functions will not be > called upon hibernation - that leads to system crash on ARM during > freezing if gpio-led is used in combination with CPU led trigger. > It may happen after freeze_noirq stage (GPIO is suspended) > and before syscore_suspend stage (CPU led trigger is suspended) > - usually when disable_nonboot_cpus() is called. > > Log: > PM: noirq freeze of devices complete after 1.425 msecs > Disabling non-boot CPUs ... > ^ system may crash or stuck here with message (TI AM572x) > > WARNING: CPU: 0 PID: 3100 at drivers/bus/omap_l3_noc.c:148 l3_interrupt_handler+0x22c/0x370() > 44000000.ocp:L3 Custom Error: MASTER MPU TARGET L4_PER1_P3 (Idle): Data Access in Supervisor mode during Functional access > > CPU1: shutdown > ^ or here > > Fix this by using SIMPLE_DEV_PM_OPS, which appropriately > assigns the suspend and hibernation callbacks and move > led_suspend/led_resume under CONFIG_PM_SLEEP to avoid > build warnings. > > Signed-off-by: Grygorii Strashko > --- > This patch actually fixes commit: > 73e1ab4 "leds: Convert led class driver from legacy pm ops to dev_pm_ops" > > Changes in v2: > - fixed compile time warnings when !CONFIG_PM_SLEEP > - updated commit message > > v1: > - https://lkml.org/lkml/2015/2/2/476 > > drivers/leds/led-class.c | 7 +++---- > 1 file changed, 3 insertions(+), 4 deletions(-) > > diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c > index dbeebac..5033e0d 100644 > --- a/drivers/leds/led-class.c > +++ b/drivers/leds/led-class.c > @@ -183,6 +183,7 @@ void led_classdev_resume(struct led_classdev *led_cdev) > } > EXPORT_SYMBOL_GPL(led_classdev_resume); > > +#ifdef CONFIG_PM_SLEEP > static int led_suspend(struct device *dev) > { > struct led_classdev *led_cdev = dev_get_drvdata(dev); > @@ -202,11 +203,9 @@ static int led_resume(struct device *dev) > > return 0; > } > +#endif > > -static const struct dev_pm_ops leds_class_dev_pm_ops = { > - .suspend = led_suspend, > - .resume = led_resume, > -}; > +static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume); > > /** > * led_classdev_register - register a new object of led_classdev class. > Could you pay attention on this patch, pls? It fixes a real issue for me. Actually, I'd like to note that it fixes regression introduced by commit 73e1ab41a80d36207e8ea7cc2c9897afdeeef387 "leds: Convert led class driver from legacy pm ops to dev_pm_ops" from Shuah Khan (Jun 20 2013). -- regards, -grygorii