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=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 8A9C0C433B4 for ; Fri, 9 Apr 2021 06:44:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6ED6B610CF for ; Fri, 9 Apr 2021 06:44:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233429AbhDIGoS (ORCPT ); Fri, 9 Apr 2021 02:44:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:38212 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233296AbhDIGoR (ORCPT ); Fri, 9 Apr 2021 02:44:17 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 25587600D1; Fri, 9 Apr 2021 06:44:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1617950643; bh=V+LPiS0wXCRM9r81HlzxVPlmm7L5lizNQhFVG2u7um8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=pzv2hpNuXzf7F2BF2g/8vlx74EDIbL7qL/ClY0Xvd4vd3JULuQgf4b+YJQdg7hSlD ZGU4109EA9e2jqdJPwHBZquTapquati/4XiTBK075OuqzsAqVtAHfkfWF0iUBdhFZC ignMUzPm3nLcLUuWtkvLes7qLJJK9N/o9mhke3AY= Date: Fri, 9 Apr 2021 08:44:01 +0200 From: Greg KH To: Min Li Cc: "derek.kiernan@xilinx.com" , "dragan.cvetic@xilinx.com" , "arnd@arndb.de" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH net-next v3 2/2] misc: Add Renesas Synchronization Management Unit (SMU) support Message-ID: References: <1617846650-10058-1-git-send-email-min.li.xe@renesas.com> <1617846650-10058-2-git-send-email-min.li.xe@renesas.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 08, 2021 at 06:59:19PM +0000, Min Li wrote: > > > > But what does that have to do with the misc device? > > > > Hi Greg, MFD driver is the start of everything. Once MFD driver is loading, it will spawn 2 devices, > one is for phc driver, which is under /driver/ptp and the other one is for this misc driver. > Both PHC and misc drivers are operating on the same device. > They are both calling exported functions from mfd drivers to access the device through i2c/spi > and the register definitions are located in include/Linux/mfd/idt8a340_reg.h or idt82p33_reg.h > depending on which device was found by mfd driver through device tree node. I don't think it's a good idea to have the same defines with different values in different files, that's just a problem waiting to happen... good luck! greg k-h