From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: NAK new drivers without proper power management? Date: Sat, 10 Feb 2007 01:12:23 +0100 Message-ID: <200702100112.24341.rjw@sisk.pl> References: <1171058269.1484.64.camel@nigel.suspend2.net> <200702100012.17430.rjw@sisk.pl> <1171063690.1484.113.camel@nigel.suspend2.net> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <1171063690.1484.113.camel@nigel.suspend2.net> Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.osdl.org Errors-To: linux-pm-bounces@lists.osdl.org To: nigel@nigel.suspend2.net Cc: pm list , LKML , Arjan van de Ven List-Id: linux-pm@vger.kernel.org On Saturday, 10 February 2007 00:28, Nigel Cunningham wrote: > Hi. > = > On Sat, 2007-02-10 at 00:12 +0100, Rafael J. Wysocki wrote: > > > > I think if CONFIG_PM_DEBUG is set, the core should warn about drive= rs not > > > > having .suspend or .resume routines. > > > = > > > The only problem with that is, not everyone turns on CONFIG_PM_DEBUG. > > > CONFIG_PM instead? > > = > > Well, I can imagine a driver that doesn't need a .suspend routine, for = example, > > and I don't think we should make the kernel always complain about that. > = > How about... > = > #ifdef CONFIG_PM_PARANOIA > static int empty_suspend_routine(struct device *dev, pm_message_t state) > { > return 0; > } > #define empty_suspend empty_suspend_routine > #else > #define empty_suspend NULL > #endif > = > ... > = > .suspend =3D empty_suspend; > ... > = > = > Then CONFIG_PM_PARANOIA can be enabled by default for now, and when we > eventually device it's not needed anymore, someone can submit a patch > replacing either turning off the CONFIG by default or removing the whole > mechanism. I think that would be tempting people to abuse it, for example by defining = or undefining things just to quieten the warning. In my opinion the only way to make the warning go away should be to define a non-NULL .suspend (.resume) routine and that's why I don't think the warn= ing should be mandatory. > > I think if someone doesn't set CONFIG_PM_DEBUG, we can ask him to set it > > and report back. > = > We can, but the whole point to the suggestion was to make your life and > mine easier, as well as those of our users. > = > Making it dependent on CONFIG_PM instead achieves that by: > - Saving you, I and distro people from having to tell their users to > enable the option (and how to) I think the distro people can patch their kernels to fit their needs. > - Saving the users the problem of going through all the steps, making > mistakes, potentially ending up with unbootable systems because they > make mistakes and so on. > = > This way, they just need to look in dmesg. Well, IMO, if someone doesn't know how to compile and install the kernel, he'll be using a distro kernel anyway and then see above. Otherwise we can safely ask him to turn on whatever debugging options we need. Greetings, Rafael -- = If you don't have the time to read, you don't have the time or the tools to write. - Stephen King