From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752017AbaKKVOA (ORCPT ); Tue, 11 Nov 2014 16:14:00 -0500 Received: from avon.wwwdotorg.org ([70.85.31.133]:34615 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751762AbaKKVN7 (ORCPT ); Tue, 11 Nov 2014 16:13:59 -0500 Message-ID: <54627C1F.9050200@wwwdotorg.org> Date: Tue, 11 Nov 2014 14:14:07 -0700 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Olof Johansson , thierry.reding@gmail.com, gnurou@gmail.com CC: linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, gregkh@linux-foundation.org, Laxman Dewangan Subject: Re: [PATCH] ARM: dts: tegra: move serial aliases to per-board References: <1415738970-7963-1-git-send-email-olof@lixom.net> In-Reply-To: <1415738970-7963-1-git-send-email-olof@lixom.net> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/11/2014 01:49 PM, Olof Johansson wrote: > There are general changes pending to make the /aliases/serial* entries > number the serial ports on the system. On tegra, so far the ports have been > just numbered dynamically as they are configured so that makes them change. > > To avoid this, add specific aliases per board to keep the old numbers. This > allows us to change the numbering by default on future SoCs while keeping the > numbering on existing boards. This change seems mostly OK to me. FWIW though, I had suggested this approach when the UART aliases were first added, and Laxman disagreed with it. See commit b6551bb933f9 "ARM: tegra: dts: add aliases and DMA requestor for serial controller", and its discussion: https://lkml.org/lkml/2012/12/25/4. I've CC'd Laxman in case he still objects. > Signed-off-by: Olof Johansson > --- > > Stephen/Thierry/Alex, as noticed this week we really should try to get > this in before the 3.19 merge window so that the global aliases change > can happen there without regression. How did we resolve the issue that patch causes with old DTs; namely that it causes a change in behaviour for those old DTs? On IRC, I'd wondered whether we should set a flag so the kernel ignored aliases for boards containing currently upstreamed Tegra SoCs so that issue wouldn't occur. If we did that, we wouldn't need this patch.