Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753183AbXBKMOX (ORCPT ); Sun, 11 Feb 2007 07:14:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932378AbXBKMOX (ORCPT ); Sun, 11 Feb 2007 07:14:23 -0500 Received: from cavan.codon.org.uk ([217.147.92.49]:38710 "EHLO vavatch.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753182AbXBKMOU (ORCPT ); Sun, 11 Feb 2007 07:14:20 -0500 Date: Sun, 11 Feb 2007 12:13:40 +0000 From: Matthew Garrett To: Willy Tarreau Cc: "Rafael J. Wysocki" , Daniel Barkalow , nigel@nigel.suspend2.net, Robert Hancock , linux-kernel , Jeff Garzik , Pavel Machek , pm list Message-ID: <20070211121339.GB4204@srcf.ucam.org> References: <200702101130.44471.rjw@sisk.pl> <200702102050.28218.rjw@sisk.pl> <20070211065404.GA943@1wt.eu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070211065404.GA943@1wt.eu> User-Agent: Mutt/1.5.12-2006-07-14 X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: mjg59@codon.org.uk Subject: Re: [PATCH] Re: NAK new drivers without proper power management? X-SA-Exim-Version: 4.2.1 (built Tue, 20 Jun 2006 01:35:45 +0000) X-SA-Exim-Scanned: Yes (on vavatch.codon.org.uk) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1050 Lines: 21 On Sun, Feb 11, 2007 at 07:54:04AM +0100, Willy Tarreau wrote: > instead of modifying all drivers to explicitly state that they don't support > it, we should start with a test of the NULL pointer for .suspend which should > mean exactly the same without modifying the drivers. I find it obvious that > a driver which does provide a suspend function will not support it. And if > some drivers (eg /dev/null) can support it anyway, it's better to change > *those* drivers to explicitly mark them as compatible. No, that doesn't work. In the absence of suspend/resume methods, the PCI layer will implement basic PM itself. In some cases, this works. In others, it doesn't. There's no way to automatically determine which is which without modifying the drivers. -- Matthew Garrett | mjg59@srcf.ucam.org - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/