From: David Brownell <david-b@pacbell.net>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: Totally broken PCI PM calls
Date: Mon, 11 Oct 2004 20:00:53 -0700
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Cc: Dmitry Torokhov <dtor_core@ameritech.net>,
       Linux Kernel list <linux-kernel@vger.kernel.org>,
       Paul Mackerras <paulus@samba.org>, Linus Torvalds <torvalds@osdl.org>,
       Andrew Morton <akpm@osdl.org>, Pavel Machek <pavel@ucw.cz>
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On Monday 11 October 2004 4:08 pm, Benjamin Herrenschmidt wrote:
> On Tue, 2004-10-12 at 08:58, Dmitry Torokhov wrote:
> 
> > Yes, I think that devices that failed to resume (and all their children)
> > have to be moved by the core resume function into a separate list and
> > then destroyed (again by the driver core). 

OHCI has to do this when the controller loses power during suspend;
which includes many suspend-to-disk cases.  It marks the devices dead,
kills the I/O queues, and then makes khubd do all the work.


> > For that we might need to add 
> > bus_type->remove_device() handler as it seems that all buses do alot
> > of work outside of driver->remove handlers. The remove_device should
> > accept additional argument - something like dead_device that would
> > suggest that driver should not be alarmed by any errors during unbind/
> > removal process as the device (or rather usually its parent) is simply
> > not there anynore.
> 
> They already do... think USB...

USB decided against the extra argument; drivers don't much care
at that point.  And anyway, they can tell the device is gone by looking
at status codes returned by URB completion or submission.

- Dave


> Ben.
> 
> 
> 
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