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Date: Wed, 20 Jul 2016 09:23:59 +0200
From: Lukas Wunner <lukas@wunner.de>
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Linux PCI <linux-pci@vger.kernel.org>,
	Linux PM <linux-pm@vger.kernel.org>,
	Andreas Noever <andreas.noever@gmail.com>,
	Alan Stern <stern@rowland.harvard.edu>,
	Huang Ying <ying.huang@intel.com>
Subject: Re: [PATCH v2 00/13] Runtime PM for Thunderbolt on Macs
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References: <cover.1463134231.git.lukas@wunner.de>
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On Fri, Jul 08, 2016 at 03:28:12AM +0200, Rafael J. Wysocki wrote:
> On Thu, Jul 7, 2016 at 5:02 PM, Lukas Wunner <lukas@wunner.de> wrote:
> > (1) Would it be possible to allow dev_pm_domain_set() for already
> >     bound devices? (It would allow me to simplify this series
> >     considerably.)
> 
> I don't think so, because setting a PM domain generally changes the
> set of PM callbacks for the device and it may not be safe to call it
> after the driver has been bound.

That sounds more like a locking problem than anything else.

If the system is awake and the device is active, it would seem safe
to change its set of PM callbacks. Am I missing something?

How about checking in dev_pm_domain_set() if pm_runtime_active(dev)
and calling lock_system_sleep() / unlock_system_sleep() to ensure that?

Thanks,

Lukas