From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752135AbXDDRmr (ORCPT ); Wed, 4 Apr 2007 13:42:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752140AbXDDRmr (ORCPT ); Wed, 4 Apr 2007 13:42:47 -0400 Received: from thunk.org ([69.25.196.29]:49996 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752135AbXDDRmq (ORCPT ); Wed, 4 Apr 2007 13:42:46 -0400 Date: Wed, 4 Apr 2007 13:41:53 -0400 From: Theodore Tso To: "H. Peter Anvin" Cc: David Miller , dwmw2@infradead.org, paulus@samba.org, alan@lxorguk.ukuu.org.uk, flar@allandria.com, linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Stop pmac_zilog from abusing 8250's device numbers. Message-ID: <20070404174153.GI31973@thunk.org> Mail-Followup-To: Theodore Tso , "H. Peter Anvin" , David Miller , dwmw2@infradead.org, paulus@samba.org, alan@lxorguk.ukuu.org.uk, flar@allandria.com, linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org References: <1175663999.2932.8.camel@shinybook.infradead.org> <17939.15726.114059.679277@cargo.ozlabs.ibm.com> <1175666635.2932.17.camel@shinybook.infradead.org> <20070404.011208.120446173.davem@davemloft.net> <20070404083803.GA13134@flint.arm.linux.org.uk> <20070404122154.GF31973@thunk.org> <4613CF6A.2090407@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4613CF6A.2090407@zytor.com> User-Agent: Mutt/1.5.13 (2006-08-11) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on thunker.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 04, 2007 at 09:16:42AM -0700, H. Peter Anvin wrote: > One option would be to move the 8250-based serial ports, to, say, > /dev/ttyN* (for National Semiconductors -- the best I could come up > with) and redefine /dev/ttyS* as a serial port multiplexer which maps in > all the types, for the ones that really want dynamic mapping. > Of course, now you have the potential of aliasing, again, which tends to > cause all kinds of headaches w.r.t. locking. That would break the 99.9% of the the world using Intel-based systems which only have 8250's, for very little gain. Like it or not, /dev/ttySx and 8250 UART's are to serial ports what the PCI is to system buses.... - Ted