From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966242AbcIHJvN (ORCPT ); Thu, 8 Sep 2016 05:51:13 -0400 Received: from mail-pa0-f68.google.com ([209.85.220.68]:34477 "EHLO mail-pa0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965564AbcIHJvK (ORCPT ); Thu, 8 Sep 2016 05:51:10 -0400 Subject: Re: [PATCH V2 3/4] ARM64 LPC: support serial based on low-pin-count To: Arnd Bergmann , linux-arm-kernel@lists.infradead.org References: <1473255233-154297-1-git-send-email-yuanzhichang@hisilicon.com> <1473255233-154297-4-git-send-email-yuanzhichang@hisilicon.com> <5345060.9D0B4ujt5e@wuerfel> Cc: Zhichang Yuan , linuxarm@huawei.com, linux-kernel@vger.kernel.org, lorenzo.pieralisi@arm.com, minyard@acm.org, benh@kernel.crashing.org, gabriele.paoloni@huawei.com, john.garry@huawei.com, liviu.dudau@arm.com, zourongrong@gmail.com From: zhichang X-Enigmail-Draft-Status: N1110 Message-ID: <57D1349D.8070905@gmail.com> Date: Thu, 8 Sep 2016 17:51:25 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.7.2 MIME-Version: 1.0 In-Reply-To: <5345060.9D0B4ujt5e@wuerfel> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Arnd On 2016年09月07日 22:50, Arnd Bergmann wrote: > On Wednesday, September 7, 2016 9:33:52 PM CEST Zhichang Yuan wrote: >> From: "zhichang.yuan" >> >> On Hip06 platform, a 16550 compatible UART is connected to low-pin-count and >> controlled through the LPC I/O cycles. This patch drives the UART port with >> the specific serial in/out function pair based on the indirect-IO mechanism >> introduced by Hip06 LPC driver. >> >> Signed-off-by: zhichang.yuan > > Any reason this cannot just use the regular drivers/tty/serial/8250/8250_of.c > driver? I think two reasons for that: 1. 8250_of.c is only for devicetree, but we need to support ACPI device too; 2. It seems UPIO_PORT is not supported there. Best, Zhichang > > Arnd >