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Date: Mon, 12 Apr 2010 13:43:49 +0200 (CEST)
From: Jiri Kosina <jkosina@suse.cz>
To: =?ISO-8859-15?Q?Bruno_Pr=E9mont?= <bonbons@linux-vserver.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>, linux-input@vger.kernel.org,
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       "Rick L. Vinyard Jr." <rvinyard@cs.nmsu.edu>,
       Nicu Pavel <npavel@ituner.com>, Oliver Neukum <oliver@neukum.org>
Subject: Re: [PATCH v6 7/8, needs improvement] hid: add suspend/resume hooks
 for hid drivers
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On Sun, 11 Apr 2010, Bruno Prémont wrote:

> > > As far as I understand the code, in auto-suspend case if the driver 
> > > sends commands to the device it will have to call usbhid_wait_io(). 
> > > Please correct me if I'm wrong!
> > 
> > It's not needed. There is a queuing mechanism in place on 
> > 'resumption_waker' workqueue.
> 
> So the driver is not allowed to ask the device to do something
> at auto-suspend time (as that would abort the auto-suspension).

What do you mean by "is not allowed" exactly?

Yes, it will wake the device up from auto-suspension. However, that's 
usually what you want to happen, is there is anything you need to dispatch 
to the device, isn't it?

What exactly is the situation you are trying to handle?

Thanks,

-- 
Jiri Kosina
SUSE Labs, Novell Inc.