From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C9CA3C67863 for ; Fri, 19 Oct 2018 00:13:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 829912145D for ; Fri, 19 Oct 2018 00:13:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 829912145D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726634AbeJSIRJ (ORCPT ); Fri, 19 Oct 2018 04:17:09 -0400 Received: from gate.crashing.org ([63.228.1.57]:40435 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725910AbeJSIRI (ORCPT ); Fri, 19 Oct 2018 04:17:08 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id w9INWO4S009643; Thu, 18 Oct 2018 18:32:27 -0500 Message-ID: Subject: Re: [[PATCH] 8/9] DMA-UART-Driver-for-AST2500 From: Benjamin Herrenschmidt To: Vinod Cc: "sudheer.v" , Rob Herring , Mark Rutland , Greg Kroah-Hartman , Joel Stanley , Andrew Jeffery , Russell King , Dan Williams , Jiri Slaby , Thomas Gleixner , Marc Zyngier , Christian Borntraeger , Michael Moese , Hendrik Brueckner , Kate Stewart , Philippe Ombredanne , dmaengine@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, Sudheer V , ShivahShankar Shakarnarayan rao Date: Fri, 19 Oct 2018 10:32:24 +1100 In-Reply-To: <20181018095507.GC2400@vkoul-mobl> References: <1539749466-3912-1-git-send-email-open.sudheer@gmail.com> <1539749466-3912-9-git-send-email-open.sudheer@gmail.com> <20181017060531.GU2400@vkoul-mobl> <351eecd5b1b21893e94f76b34c058c6257b7f837.camel@kernel.crashing.org> <20181018095507.GC2400@vkoul-mobl> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5 (3.28.5-1.fc28) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2018-10-18 at 15:25 +0530, Vinod wrote: > > > It's not a dmaengine driver. It's a serial UART driver that happens to > > use a dedicated DMA engine. > > Then I see no reason for it to use dmaengine APIs. The framework allows > people to share a controller for many clients, but if you have dedicated > one then you may use it directly Well... the engine is shared by a few UARTs, they have dedicated rings but there's a common set of regs for interrupt handling etc. That said, I still think it could be contained within a UART driver, there's little benefit in adding the framework overhead, esp since these are really weak cores, any overhead will be felt. Ben. > > It's unclear whether it should be split into two drivers, or just have > > the serial driver directly use the dma engine since that engine is > > dedicated in HW to only work on those UARTs and nothing else... > > > > Cheers, > > Ben. > > > > > > > While doing resubmission please take some time to understand subsystem > > > tags to use. (hint git log will tell you) > > > > > > Also series has [[PATCH] 8/9] whereas it should be [PATCH 8/9] please > > > let git generate that for you (hint git format-patch start..end does a > > > good job) > > > > > > > @@ -0,0 +1,1594 @@ > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > +/* > > > > + * drivers/tty/serial/8250/8250_aspeed_uart_dma.c > > > > + * 1. 2018/07/01 Shivah Shankar created > > > > + * 2. 2018/08/25 sudheer.veliseti modified > > > > > > we dont use this log in kernel. I do not see s-o-b by Shivah, that > > > should be added. I think he should be author and you need to list > > > changes you did.. > > > > >