From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759821AbXLMI0i (ORCPT ); Thu, 13 Dec 2007 03:26:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753525AbXLMI02 (ORCPT ); Thu, 13 Dec 2007 03:26:28 -0500 Received: from gateway.drzeus.cx ([85.8.24.16]:55561 "EHLO smtp.drzeus.cx" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752740AbXLMI01 (ORCPT ); Thu, 13 Dec 2007 03:26:27 -0500 Date: Thu, 13 Dec 2007 09:26:21 +0100 From: Pierre Ossman To: Bjorn Helgaas Cc: Jiri Slaby , Andrew Morton , matthew@wil.cx, Linux Kernel Mailing List , linux-pm@lists.linux-foundation.org, linux-acpi@vger.kernel.org, Adam Belay , Matthieu Castet , Li Shaohua , Len Brown , Kristen Carlson Accardi , "Rafael J. Wysocki" Subject: Re: PNP: do not stop/start devices in suspend/resume path Message-ID: <20071213092621.7cf6ee87@poseidon.drzeus.cx> In-Reply-To: <200712061625.57660.bjorn.helgaas@hp.com> References: <4745F77C.7040402@gmail.com> <47514CE2.3000600@gmail.com> <200712051124.18852.bjorn.helgaas@hp.com> <200712061625.57660.bjorn.helgaas@hp.com> X-Mailer: Claws Mail 3.1.0 (GTK+ 2.12.3; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg=PGP-SHA1; boundary="=_hera.drzeus.cx-25559-1197534386-0001-2" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a MIME-formatted message. If you see this text it means that your E-mail software does not support MIME-formatted messages. --=_hera.drzeus.cx-25559-1197534386-0001-2 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Thu, 6 Dec 2007 16:25:57 -0700 Bjorn Helgaas wrote: > PNP: do not stop/start devices in suspend/resume path >=20 > Do not disable PNP devices in the suspend path. We still call > the driver's suspend method, which should prevent further use of > the device, and the protocol suspend method, which may put the > device in a low-power state. >=20 > I'm told that Windows puts devices in a low-power state (Linux > does this in the protocol suspend method), but does not use _DIS > in the suspend path. Other relevant references: >=20 > - In the ACPI 3.0b spec, I can't find any mention of _DIS in > connection with sleep. And Device Object Notifications, > Section 5.6.3, Table 5-43, says we should get a bus check > after awakening if hardware was removed while we slept. >=20 > - This: http://msdn2.microsoft.com/en-us/library/ms810079.aspx > makes a similar point about how the OS re-enumerates devices > as a result of a power state change (3rd last paragraph of > text). >=20 > - This: http://msdn2.microsoft.com/en-us/library/aa489874.aspx > suggests that Windows only stops a device to rebalance hardware > resources. >=20 > Signed-off-by: Bjorn Helgaas >=20 Tested-by: Pierre Ossman No noticeable issues with suspend or hibernate using this patch. Rgds Pierre --=_hera.drzeus.cx-25559-1197534386-0001-2 Content-Type: application/pgp-signature; name="signature.asc" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) iD8DBQFHYOyt7b8eESbyJLgRAkFQAJ9DDfb9L2gXYVF32hxFgu9hpHPNfwCguypF kLYBUDCTxW9Rm445Ts7Iiq4= =9Wkm -----END PGP SIGNATURE----- --=_hera.drzeus.cx-25559-1197534386-0001-2--