From mboxrd@z Thu Jan  1 00:00:00 1970
From: catalin.marinas@arm.com (Catalin Marinas)
Date: Thu, 9 Oct 2014 11:36:56 +0100
Subject: [PATCH 12/44] mfd: ab8500-sysctrl: Register with kernel poweroff
 handler
In-Reply-To: <20141007080048.GB25331@lee--X1>
References: <1412659726-29957-1-git-send-email-linux@roeck-us.net>
 <1412659726-29957-13-git-send-email-linux@roeck-us.net>
 <20141007080048.GB25331@lee--X1>
Message-ID: <20141009103656.GF17836@e104818-lin.cambridge.arm.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Tue, Oct 07, 2014 at 09:00:48AM +0100, Lee Jones wrote:
> On Mon, 06 Oct 2014, Guenter Roeck wrote:
> > --- a/drivers/mfd/ab8500-sysctrl.c
> > +++ b/drivers/mfd/ab8500-sysctrl.c
> > @@ -6,6 +6,7 @@
> 
> [...]
> 
> > +static int ab8500_power_off(struct notifier_block *this, unsigned long unused1,
> > +			    void *unused2)
> >  {
> >  	sigset_t old;
> >  	sigset_t all;
> > @@ -34,11 +36,6 @@ static void ab8500_power_off(void)
> >  	struct power_supply *psy;
> >  	int ret;
> >  
> > -	if (sysctrl_dev == NULL) {
> > -		pr_err("%s: sysctrl not initialized\n", __func__);
> > -		return;
> > -	}
> 
> Can you explain the purpose of this change please?

I guess it's because the sysctrl_dev is already initialised when
registering the power_off handler, so there isn't a way to call the
above function with a NULL sysctrl_dev. Probably even with the original
code you didn't need this check (after some race fix in
ab8500_sysctrl_remove but races is one of the things Guenter's patches
try to address).

-- 
Catalin