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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 0FA4EC31E40 for ; Sat, 3 Aug 2019 11:22:14 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D6EEC206A2 for ; Sat, 3 Aug 2019 11:22:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="IWp/EAOr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D6EEC206A2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Subject:To:From:Message-ID:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=CGoYW5/7IB5Zn+ZIO6zfNZubHxsjudpLxhKpZUXAk3I=; b=IWp/EAOrxPH88i BF3M44aEtfeeJcVfHxkon/mfTjrAVfUToLuXlJ5oRG2w9ioCNnxcaTJk5BV/q/68gUZ1WJSfuUpGV +3ub7rwnQRjh2T6DXK6qNG+XQe8J7aKU/GymOjXbq3ZhAZ4J94TgFpiSUJsVIZRemBg6UTGfeUMe+ WfIXg2X4Tsy/SZUzgnWZISbt+N0cYSsMqpwIrBpM7tDEPEafWl66ZpLFsID7OfiqDa2j8PrVS31eu /+77TGG8zdQW3aJax/AOoT/fM5HqcEvQo8AKR66S318GboQ5e6vNFhqPppWtHvwh9xUgwogkJWYIv bprv18OxiQupdwchTfng==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hts73-0007sq-CB; Sat, 03 Aug 2019 11:22:13 +0000 Received: from mx2.suse.de ([195.135.220.15] helo=mx1.suse.de) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hts70-0007rx-Gp for linux-arm-kernel@lists.infradead.org; Sat, 03 Aug 2019 11:22:11 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id BF9CCAD3B; Sat, 3 Aug 2019 11:22:06 +0000 (UTC) Date: Sat, 03 Aug 2019 13:22:09 +0200 Message-ID: From: Takashi Iwai To: Christoph Hellwig Subject: Re: [PATCH 5/5] dma-mapping: remove ARCH_NO_COHERENT_DMA_MMAP In-Reply-To: <20190803103024.GA32624@lst.de> References: <20190725063401.29904-1-hch@lst.de> <20190725063401.29904-6-hch@lst.de> <20190802070354.GA8280@lst.de> <20190803103024.GA32624@lst.de> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190803_042210_702180_274B8A08 X-CRM114-Status: GOOD ( 17.34 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-xtensa@linux-xtensa.org, Michal Simek , linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-m68k@lists.linux-m68k.org, Robin Murphy , x86@kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, Marek Szyprowski Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sat, 03 Aug 2019 12:30:24 +0200, Christoph Hellwig wrote: > > On Fri, Aug 02, 2019 at 10:24:02AM +0200, Takashi Iwai wrote: > > I wasn't careful enough to look at that change, sorry. > > > > The code there tries to check whether dma_mmap_coherent() would always > > fail on some platforms. Then the driver clears the mmap capability > > flag at the device open time and notifies user-space to fall back to > > the dumb read/write mode. > > > > So I'm afraid that simply dropping the check would cause the behavior > > regression, e.g. on PARISC. > > > > Is there any simple way to test whether dma_mmap_coherent() would work > > or not in general on the target platform? It's not necessarily in an > > ifdef at all. > > This isn't really a platform, but a per-device question. I can add a > "bool dma_can_mmap(struct device *dev)" helper to check that. Yes, this would fit perfect. > But how > do I get at a suitable struct device in hw_support_mmap()? substream->dma_buffer.dev.dev can be that, which is used in the mmap helper side, snd_pcm_lib_default_mmap(). Thanks! Takashi _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel