From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: Null suspend/resume functions Date: Mon, 16 Nov 2009 20:07:11 +0100 Message-ID: <200911162007.11963.rjw@sisk.pl> References: <20091109133136.GC1245@sirena.org.uk> <20091116153000.GB29479@sirena.org.uk> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20091116153000.GB29479@sirena.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: Mark Brown Cc: Kuninori Morimoto , alsa-devel@alsa-project.org, linux-pm@lists.linux-foundation.org, Magnus Damm , linux-kernel@vger.kernel.org List-Id: alsa-devel@alsa-project.org On Monday 16 November 2009, Mark Brown wrote: > On Mon, Nov 09, 2009 at 01:31:36PM +0000, Mark Brown wrote: > > On Mon, Nov 09, 2009 at 10:58:58AM +0000, Mark Brown wrote: > > > On Mon, Nov 09, 2009 at 11:54:47AM +0900, Kuninori Morimoto wrote: > > Any chance someone from the PM side could comment on the issue below? There is. I haven't had a chance to look at it yet, will do shortly. > > > > +static int fsi_runtime_nop(struct device *dev) > > > > +{ > > > > + /* Runtime PM callback shared between ->runtime_suspend() > > > > + * and ->runtime_resume(). Simply returns success. > > > > + * > > > > + * This driver re-initializes all registers after > > > > + * pm_runtime_get_sync() anyway so there is no need > > > > + * to save and restore registers here. > > > > + */ > > > > + return 0; > > > > +} > > > > > > This sets off alarm bells but it's perfectly reasonable, especially with > > > platforms able to put things into a low power state with no explicit > > > driver code now they can do power domain style things like SH. I've > > > CCed in the PM folks since this seems like a perfectly reasonable use > > > case which ought to be handled more nicely. Thanks, Rafael