Re: [PATCH v3] Add "shutdown" to "struct class".

From: Josh Zimmerman <joshz-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
To: "Winkler, Tomas" <tomas.winkler-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Cc: Greg Kroah-Hartman
	<gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>,
	"tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org"
	<tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>,
	"linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
	<linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
Subject: Re: [PATCH v3] Add "shutdown" to "struct class".
Date: Thu, 18 May 2017 08:20:53 -0700	[thread overview]
Message-ID: <CAHSjozAQcMHSsbq-D4ytOk+qMa=3btx1UkF6rctsa2p8U8Gv1w@mail.gmail.com> (raw)
In-Reply-To: <5B8DA87D05A7694D9FA63FD143655C1B641D90DB-Jy8z56yoSI8MvF1YICWikbfspsVTdybXVpNB7YpNyf8@public.gmane.org>

Are there any more changes any of you would like to see in this patch?

Thanks!
Josh

On Mon, May 15, 2017 at 1:49 PM, Winkler, Tomas <tomas.winkler-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> wrote:
>
>
>> -----Original Message-----
>> From: Jason Gunthorpe [mailto:jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org]
>> Sent: Monday, May 15, 2017 20:46
>> To: Josh Zimmerman <joshz-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
>> Cc: Greg Kroah-Hartman <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>; linux-
>> kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; Winkler, Tomas <tomas.winkler-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>; Jarkko
>> Sakkinen <jarkko.sakkinen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>; tpmdd-
>> devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
>> Subject: Re: [PATCH v3] Add "shutdown" to "struct class".
>>
>> On Mon, May 15, 2017 at 10:39:08AM -0700, Josh Zimmerman wrote:
>> > (Continuing thread from patch v1)
>> > > > On Sat, May 13, 2017 at 12:43:11PM +0000, Winkler, Tomas wrote:
>> > > > > > The TPM class has some common shutdown code that must be
>> > > > > > executed for all drivers. This adds some needed functionality
>> > > > > > for that
>> > > > >
>> > > > > The issue with this is, that on some platforms the only storage
>> > > > > can be eMMC and TPM is using it,. It has to be ensured that the
>> > > > > storage device won't go down before TPM2_shutdown is called.
>> > > > > And there is no direct device hierarchy to ensure an orderly
>> shutdown.
>> > > >
>> > > > Something will have to use the new device links stuff to define
>> > > > that dependency, but that seems unrelated to this patch?
>> > >
>> > >
>> > > Yep, it's not directly related to this specific patch, this is more relevant
>> particularly to TPM2_shutdown.
>> >
>> > Jason, do you want me to do that in my patch on the tpmdd-devel list?
>> > If so, mind giving me a documentation pointer or two? I'm not familiar
>> > with this area.
>>
>> No.. Ordering power management events is something someone with
>> knowledge of the specific emmc platform is going to have to tackle..
>> It isn't really a core problem, platform specific code will have to setup the
>> needed device links to order power management properly..
>
> eMMC is just an example, that can be other storage device (ufs, nvme) and some type of abstraction of underlying storage
> dependency would be required. I just wanted to put it on the table, not sure it has to be solved in this round.
> Tomas
>
>
>
>
>>
>> Jason

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