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=-1.0 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 B19ACC43441 for ; Fri, 9 Nov 2018 22:33:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7BB9820827 for ; Fri, 9 Nov 2018 22:33:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7BB9820827 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arndb.de 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 S1728294AbeKJIPy (ORCPT ); Sat, 10 Nov 2018 03:15:54 -0500 Received: from mail-qk1-f196.google.com ([209.85.222.196]:45744 "EHLO mail-qk1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726306AbeKJIPx (ORCPT ); Sat, 10 Nov 2018 03:15:53 -0500 Received: by mail-qk1-f196.google.com with SMTP id d135so4463996qkc.12; Fri, 09 Nov 2018 14:33:16 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=d5b1sHamJErQlHBdiqqeqNmArA6ZPJTXRSbT7EBxxuM=; b=lKM68fqKdluzwJaeOVnt25VWWOB7x5iGKU8vfL5n3gfwToSPX4UDeZskp71WlQvyCw v5NkSgve3Rb8eSYNVX1h9cImjwtBMtNcu73ULPdqccne1hXce2lNesvhgQY5BtxMin/x 08nJ+f+s6WasdmsiEbxMgN8ULbyDt0fqbP6Cv6NgfPb5MeTvcndvUvdvd2QHiGseQPN6 EmqsdG5/iCNfmiEZz0H7UCdpRS/ZxqsWD5WWxqKVmeqorffZDlhK0XjtAqREHW8sRv0y 37esO7WGyqsc5ixQQ1faV3WvAAdL3oWBn8oSrMzrTm/nX4jJfHLuv3CIoW7pPljJyd70 +s8g== X-Gm-Message-State: AGRZ1gLJ7Uobc7yf7GV1OZTYkV4NqfY2kHx0ktNtSZCGZlkucOm/x7mA gdaV0bgkvSRLCXhIVcaA3MN1RiNI+As7UtPQQB0= X-Google-Smtp-Source: AJdET5cACwczp8E3S8n836ioPdZiiK4/ttinqSI+I2vVrEHd/rwNcPhWCgtvvEOVvz+cnW4bShWJ9+IVncLOPeQkqK4= X-Received: by 2002:ac8:7451:: with SMTP id h17mr10289092qtr.319.1541802795930; Fri, 09 Nov 2018 14:33:15 -0800 (PST) MIME-Version: 1.0 References: <20181104155501.14767-1-TheSven73@googlemail.com> In-Reply-To: From: Arnd Bergmann Date: Fri, 9 Nov 2018 23:32:50 +0100 Message-ID: Subject: Re: [PATCH anybus v3 0/6] Support HMS Profinet Card over Anybus To: Sven Van Asbroeck Cc: svendev@arcx.com, Rob Herring , Linus Walleij , Linux Kernel Mailing List , DTML Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 9, 2018 at 10:47 PM Sven Van Asbroeck wrote: > > On Fri, Nov 9, 2018 at 4:22 PM Arnd Bergmann wrote: > > > > > > As usual, it comes down to the user space interfaces I think. Designing > > a user interface is hard, most importantly because you cannot change it > > once anyone starts relying on it, as opposed to implementation details > > that you are free to change at any point. > > Thanks for the feedback ! > I will rework v4 so it uses a userspace interface shared with other > fieldbus drivers - uio. You mentioned this before, but I don't see how this would actually work. Isn't uio just a slim wrapper for allowing user space access to hardware registers while avoiding a kernel driver? Arnd