From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755961AbdBQHgt (ORCPT ); Fri, 17 Feb 2017 02:36:49 -0500 Received: from sci-ig2.spreadtrum.com ([222.66.158.135]:57331 "EHLO SHSQR01.spreadtrum.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1755599AbdBQHgr (ORCPT ); Fri, 17 Feb 2017 02:36:47 -0500 Date: Fri, 17 Feb 2017 15:35:11 +0800 From: Chunyan Zhang To: Arnd Bergmann CC: , , , , , , , , Subject: Re: [PATCH 4/5] sprd_serial: switch comptible string to sc-uart Message-ID: <20170217073511.GB8767@spreadtrum.com> Mail-Followup-To: Arnd Bergmann , linux-arm-kernel@lists.infradead.org, robh+dt@kernel.org, mark.rutland@arm.com, gregkh@linuxfoundation.org, catalin.marinas@arm.com, will.deacon@arm.com, orson.zhai@spreadtrum.com, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org References: <1487063952-7113-1-git-send-email-chunyan.zhang@spreadtrum.com> <1487063952-7113-5-git-send-email-chunyan.zhang@spreadtrum.com> <1761969.45NG6Q1Iyc@wuerfel> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1761969.45NG6Q1Iyc@wuerfel> User-Agent: Mutt/1.5.21 (2010-09-15) X-MAIL: SHSQR01.spreadtrum.com v1H7Zdts052564 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On ε››, 2月 16, 2017 at 02:31:38δΈ‹εˆ +0100, Arnd Bergmann wrote: > On Tuesday, February 14, 2017 5:19:11 PM CET Chunyan Zhang wrote: > > static const struct of_device_id serial_ids[] = { > > - {.compatible = "sprd,sc9836-uart",}, > > + {.compatible = "sprd,sc-uart",}, > > {} > > We really need this to be specific, in case Spreadtrum ever > makes a slightly different UART that is not 100% compatible > with this one. Also, you can't remove the string you already have, > only add to it. > > Normally when you have a new chip that is compatible with one > we already have a driver for, we mark the device as compatible > with the old one and avoid having to change the driver, e.g. > > compatible = "sprd,sc9995-uart", "sprd,sc9836-uart"; > > This way, the driver could later be changed to handle anything > that is compatible with sc9995 differently from sc9836, but > by default it would match the original string. > Right, I've addressed this when I received the same comments from Rob Herring :) Thanks for your comments, Chunyan > Arnd