From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760696AbZEMPB0 (ORCPT ); Wed, 13 May 2009 11:01:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756572AbZEMPBP (ORCPT ); Wed, 13 May 2009 11:01:15 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:38010 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754942AbZEMPBO (ORCPT ); Wed, 13 May 2009 11:01:14 -0400 Date: Wed, 13 May 2009 07:58:20 -0700 (PDT) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: Alan Cox cc: dsaxena@plexity.net, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] 8250: Don't restore NS16550 mode when console suspend is disabled In-Reply-To: <20090513094409.50c2409f@lxorguk.ukuu.org.uk> Message-ID: References: <20090512210015.GA25540@plexity.net> <20090513011842.22d9cd6c@lxorguk.ukuu.org.uk> <20090513002850.GA28422@plexity.net> <20090513094409.50c2409f@lxorguk.ukuu.org.uk> User-Agent: Alpine 2.01 (LFD 1184 2008-12-16) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 13 May 2009, Alan Cox wrote: > > Then hard coding is no improvement either. It needs to restore the mode > that was present at suspend. Alan, you're missing the fact that this is a special-case for "this is the console, and we're not suspending consoles AT ALL". IOW, it was never suspended either, and it's a case that is known to be fundamentally buggy (we're suspending all the PCI bridges, but not a serial device that may be behind them!), but often work in _practice_ (because people don't use this thing for random serial devices, but for things like integrated serial lines that don't lose power). So we _could_ just save the mode, but that isn't really what this patch is all about. The patch in question is about a total hack to avoid touching a piece of hardware that we simply don't consider normal. Linus