From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: nigel@nigel.suspend2.net
Subject: Re: NAK new drivers without proper power management?
Date: Sat, 10 Feb 2007 00:12:16 +0100
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Cc: Arjan van de Ven <arjan@infradead.org>,
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Hi,

On Friday, 9 February 2007 23:51, Nigel Cunningham wrote:
> Hi.
> 
> On Fri, 2007-02-09 at 23:44 +0100, Rafael J. Wysocki wrote:
> > On Friday, 9 February 2007 23:26, Nigel Cunningham wrote:
> > > Hi.
> > > 
> > > On Fri, 2007-02-09 at 23:17 +0100, Arjan van de Ven wrote:
> > > > On Sat, 2007-02-10 at 08:57 +1100, Nigel Cunningham wrote:
> > > > > Hi.
> > > > > 
> > > > > I don't think this is already done (feel free to correct me if I'm
> > > > > wrong)..
> > > > > 
> > > > > Can we start to NAK new drivers that don't have proper power management
> > > > > implemented? There really is no excuse for writing a new driver and not
> > > > > putting .suspend and .resume methods in anymore, is there?
> > > > 
> > > > 
> > > > to a large degree, a device driver that doesn't suspend is better than
> > > > no device driver at all, right?
> > > 
> > > I'm not sure it is. It only makes more work for everyone else: We have
> > > to help people figure out what causes their computer to fail to resume
> > > (which can take quite a while), then get them them complain to driver
> > > author, and the driver author has to submit patches to fix it.
> > > 
> > > All of this is avoided if they'll just do it right in the first place.
> > > 
> > > > now.. if you want to make the core warn about it, that's very fair
> > > 
> > > That's probably a good idea too, since I'm only suggesting this for new
> > > drivers.
> > 
> > I think if CONFIG_PM_DEBUG is set, the core should warn about drivers 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.

I think if someone doesn't set CONFIG_PM_DEBUG, we can ask him to set it
and report back.

Greetings,
Rafael
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