From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bh-25.webhostbox.net (bh-25.webhostbox.net [208.91.199.152]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 8D0E81A18E0 for ; Wed, 8 Oct 2014 04:01:08 +1100 (EST) Received: from mailnull by bh-25.webhostbox.net with sa-checked (Exim 4.82) (envelope-from ) id 1XbY8I-000RvT-O7 for linuxppc-dev@lists.ozlabs.org; Tue, 07 Oct 2014 17:01:06 +0000 Date: Tue, 7 Oct 2014 10:00:52 -0700 From: Guenter Roeck To: Alexander Graf Subject: Re: [PATCH 00/20] powerpc: Convert power off logic to pm_power_off Message-ID: <20141007170052.GB16931@roeck-us.net> References: <1412170086-57971-1-git-send-email-agraf@suse.de> <1412311350.2783.4.camel@concordia> <54326850.1030801@suse.de> <1412663147.10747.1.camel@concordia> <5433CFEB.9040104@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <5433CFEB.9040104@suse.de> Cc: Arnd Bergmann , Geoff Levand , Alistair Popple , Scott Wood , Anatolij Gustschin , linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, Oct 07, 2014 at 01:35:07PM +0200, Alexander Graf wrote: > > > On 07.10.14 08:25, Michael Ellerman wrote: > > On Mon, 2014-10-06 at 12:00 +0200, Alexander Graf wrote: > >> > >> On 03.10.14 06:42, Michael Ellerman wrote: > >>> On Wed, 2014-10-01 at 15:27 +0200, Alexander Graf wrote: > >>>> The generic Linux framework to power off the machine is a function pointer > >>>> called pm_power_off. The trick about this pointer is that device drivers can > >>>> potentially implement it rather than board files. > >>>> > >>>> Today on PowerPC we set pm_power_off to invoke our generic full machine power > >>>> off logic which then calls ppc_md.power_off to invoke machine specific power > >>>> off. > >>>> > >>>> To fix this up, let's get rid of the ppc_md.power_off logic and just always use > >>>> pm_power_off as was intended. Then individual drivers such as the GPIO power off > >>>> driver can implement power off logic via that function pointer. > >>> > >>> This looks OK to me with one caveat. > >>> > >>> In several of the patches you're replacing a static initialisation with a > >>> runtime one, and you're doing the runtime initialisation in xxx_setup_arch(). > >>> That's reasonably late, so I'd prefer you did it in xxx_probe(). > >> > >> Heh, I had it in xxx_probe() originally and then realized that > >> > >> a) the power off function is basically a driver. Driver initialization > >> happens in xxx_setup_arch() and > >> > >> b) the maple target already does overwrite its power_off callback in > >> xxx_setup_arch and > >> > >> c) on all targets xxx_probe() is very slim and doesn't do much > >> > >> but I'll happily change it back to put the bits in xxx_probe() instead. > > > > Thanks. > > > > That way you shouldn't be changing behaviour. > > > > It may still be the case that some power off routines don't actually work until > > later, but that's an existing problem. Some power off routines *do* work before > > setup_arch(), so they will continue to work. > > Ok, works for me :). Just wanted to make sure you're aware of the > reasoning why I didn't do it in probe(). > > > Also, how does your series interact with Guenter's that removes pm_power_off ? > > It seems at the moment they are unaware of each other. > > Guenters patches convert users of pm_power_off to his new scheme. We're > not even at that stage at all yet in the powerpc tree. Converting > everything to pm_power_off is basically a first step. His patch set > maintains pm_power_off, so there shouldn't be nasty conflicts. > Onlly the first m68k patch, though. The very last patch in the series remvoes pm_power_off. Guenter > Once we converted from ppc_md tables to actual code, we can just run a > simple coccinelle patch to convert from pm_power_off to his new scheme > later. > > > Alex