From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933267AbXG2SE3 (ORCPT ); Sun, 29 Jul 2007 14:04:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1764184AbXG2SEU (ORCPT ); Sun, 29 Jul 2007 14:04:20 -0400 Received: from caramon.arm.linux.org.uk ([78.32.30.218]:45379 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1764161AbXG2SET (ORCPT ); Sun, 29 Jul 2007 14:04:19 -0400 Date: Sun, 29 Jul 2007 19:03:07 +0100 From: Russell King To: Bjorn Helgaas Cc: Shaohua Li , Yinghai Lu , =?iso-8859-1?Q?S=E9bastien_Dugu=E9?= , linux-kernel , ambx1@neo.rr.com, akpm@linux-foundation.org, lenb@kernel.org, mjg59@srcf.ucam.org, castet.matthieu@free.fr Subject: Re: commit 7e92b4fc34 - x86, serial: convert legacy COM ports to platform devices - broke my serial console Message-ID: <20070729180307.GC25431@flint.arm.linux.org.uk> References: <20070724162805.76ea8328@frecb000686.frec.bull.fr> <86802c440707251737p3be3ae69qe3f91282bec8984a@mail.gmail.com> <1185416466.31345.1.camel@sli10-conroe.sh.intel.com> <200707271217.00164.bjorn.helgaas@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200707271217.00164.bjorn.helgaas@hp.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 27, 2007 at 12:16:59PM -0600, Bjorn Helgaas wrote: > For example, 8250_pnp could have rules like "COM1 should always > be ttyS0" or "a port at 0x3f8 should always be ttyS0." In which case register via the legacy ports first, and then register PNP ports. If the PNP ports correspond with legacy ports, they will re-use those slots. So, if we register 0x3f8 first (which ends up as ttyS0), followed by 0x2f8 (ttyS1) and then PNP tries to register a port at 0x2f8 then 0x3f8, you'll still end up with 0x3f8 being ttyS0 and 0x2f8 as ttyS1. > That doesn't help with Yinghai's PCI root ordering issue, of course. > But I hope that can be addressed with udev, because there's not so > much need for a persistent kernel name. If that's not enough, can > you explain more about the problem? However, aren't PNP serial ports attached to separate PNP devices? If so, udev can work it out already - they just need to look at the backing device associated with the serial port. For legacy ports that'll be serial8250.0. For PNP, it'll be some PNP device. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: