From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1MSBo4-0003Ob-F6
	for qemu-devel@nongnu.org; Sat, 18 Jul 2009 11:26:36 -0400
Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43)
	id 1MSBo0-0003OK-0O
	for qemu-devel@nongnu.org; Sat, 18 Jul 2009 11:26:35 -0400
Received: from [199.232.76.173] (port=53434 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1MSBnz-0003OH-RL
	for qemu-devel@nongnu.org; Sat, 18 Jul 2009 11:26:31 -0400
Received: from mail-ew0-f217.google.com ([209.85.219.217]:41796)
	by monty-python.gnu.org with esmtp (Exim 4.60)
	(envelope-from <filip.navara@gmail.com>) id 1MSBnz-00061l-GO
	for qemu-devel@nongnu.org; Sat, 18 Jul 2009 11:26:31 -0400
Received: by ewy17 with SMTP id 17so1208752ewy.34
	for <qemu-devel@nongnu.org>; Sat, 18 Jul 2009 08:26:30 -0700 (PDT)
MIME-Version: 1.0
In-Reply-To: <f43fc5580907180200w51098b77q7079a43f07024cbd@mail.gmail.com>
References: <E1MR5qB-0006E8-M8@lists.gnu.org>
	<f43fc5580907150833n1fb233a9v15c6a4cc55deb8d4@mail.gmail.com>
	<5b31733c0907150838j5a86dd7axa577676635644756@mail.gmail.com>
	<5b31733c0907180152x31e6a6c4g2b15b6ad2b9d3007@mail.gmail.com>
	<f43fc5580907180200w51098b77q7079a43f07024cbd@mail.gmail.com>
Date: Sat, 18 Jul 2009 17:26:29 +0200
Message-ID: <5b31733c0907180826s2cbffbc1gf494bbf126a2075a@mail.gmail.com>
Subject: Re: [Qemu-devel] [PATCH 01/14] GPIO rotary encoder implementation
From: Filip Navara <filip.navara@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Blue Swirl <blauwirbel@gmail.com>
Cc: qemu-devel@nongnu.org

On Sat, Jul 18, 2009 at 11:00 AM, Blue Swirl<blauwirbel@gmail.com> wrote:
> On Sat, Jul 18, 2009 at 11:52 AM, Filip Navara<filip.navara@gmail.com> wr=
ote:
>> On Wed, Jul 15, 2009 at 5:38 PM, Filip Navara<filip.navara@gmail.com> wr=
ote:
>>> On Wed, Jul 15, 2009 at 5:33 PM, Blue Swirl<blauwirbel@gmail.com> wrote=
:
>>>> On Wed, 15 Jul 09 16:52:12 Central Europe Standard Time, Filip Navara
>>>> <filip.navara@gmail.com> wrote:
>>>>> This patch introduces an emulation of the rotary encoder that could b=
e connected
>>>>> =A0to GPIO controller.
>>>>
>>>> How about reset handling (qemu_register_reset)?
>>>>
>>>
>>> Good point, it was on my TODO list, but I never implemented it. All
>>> the devices currently lack it. I'll include it in next version.
>>
>> On second thought the GPIO devices don't need reset handling. In real
>> hardware the rotary encoder is not affected by reset, so why would it
>> be affected in QEMU? Unfortunately to get that working correctly the
>> late_init callbacks, proposed in the devtree patches, are needed.
>
> There is still internal state (for example s->extension) that may need re=
set.
>

s->extension is part of host state actually and I don't think it
should be reset. The only emulated device that resets it is ESCC.
ADB, Musicpal, Syborg, Stellaris and xenfb never reset it (possibly
because reset callbacks are not implemented).

Best regards,
Filip Navara