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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 37335C43219 for ; Thu, 25 Apr 2019 14:31:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 277B720679 for ; Thu, 25 Apr 2019 14:31:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mev.co.uk header.i=@mev.co.uk header.b="JZJzO+mE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726961AbfDYObF (ORCPT ); Thu, 25 Apr 2019 10:31:05 -0400 Received: from smtp65.ord1d.emailsrvr.com ([184.106.54.65]:39878 "EHLO smtp65.ord1d.emailsrvr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725959AbfDYObF (ORCPT ); Thu, 25 Apr 2019 10:31:05 -0400 Received: from smtp9.relay.ord1d.emailsrvr.com (localhost [127.0.0.1]) by smtp9.relay.ord1d.emailsrvr.com (SMTP Server) with ESMTP id E5492C0289; Thu, 25 Apr 2019 10:31:03 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=mev.co.uk; s=20190130-41we5z8j; t=1556202663; bh=w18i9e5QU9exjC8EuByjFALVjeh17EI57d2TFOrUF90=; h=Subject:To:From:Date:From; b=JZJzO+mE7htKl4IHFy1AskJ48Fb1Ix37C0eA9c85Weu+N43zNibb6jlIgToS4nMUh PDGXuYf+Dl4xLuKupT9CyrDcrpYSjnRTqNCfrA7owsaUFhJb1E6MeRoE/gVgGbN8yy CSdkQ3WxzSxNfbdAG5pfD3/5LBPevrAD/RV0pkMQ= X-Auth-ID: abbotti@mev.co.uk Received: by smtp9.relay.ord1d.emailsrvr.com (Authenticated sender: abbotti-AT-mev.co.uk) with ESMTPSA id BB782C0291; Thu, 25 Apr 2019 10:31:02 -0400 (EDT) X-Sender-Id: abbotti@mev.co.uk Received: from [10.0.0.62] (remote.quintadena.com [81.133.34.160]) (using TLSv1.2 with cipher AES128-SHA) by 0.0.0.0:465 (trex/5.7.12); Thu, 25 Apr 2019 10:31:03 -0400 Subject: Re: [PATCH] dma-mapping: remove an unnecessary NULL check To: Christoph Hellwig Cc: Dan Carpenter , Jiri Slaby , Marek Szyprowski , Robin Murphy , iommu@lists.linux-foundation.org, "kernel-janitors@vger.kernel.org H Hartley Sweeten" , Greg Kroah-Hartman , linux-kernel@vger.kernel.org References: <20190424142437.GA29490@mwanda> <20190424142743.GC20974@lst.de> <3142dc82-1d4c-5f01-678e-628038d86bd6@mev.co.uk> <20190425141832.GA16643@lst.de> From: Ian Abbott Organization: MEV Ltd. Message-ID: Date: Thu, 25 Apr 2019 15:31:01 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190425141832.GA16643@lst.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 25/04/2019 15:18, Christoph Hellwig wrote: > On Thu, Apr 25, 2019 at 03:13:49PM +0100, Ian Abbott wrote: >> So for comedi_isadma, we can just replace the NULL with a pointer to a >> static dummy device with a 24-bit coherent mask? > > It should be converted to a proper isa_driver, so that it gets a real > struct device. But it will work as a short term solution? comedi_isadma isn't a driver, but is used by a few comedi drivers for ISA cards. -- -=( Ian Abbott || Web: www.mev.co.uk )=- -=( MEV Ltd. is a company registered in England & Wales. )=- -=( Registered number: 02862268. Registered address: )=- -=( 15 West Park Road, Bramhall, STOCKPORT, SK7 3JZ, UK. )=-