From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754402Ab2F1M0m (ORCPT ); Thu, 28 Jun 2012 08:26:42 -0400 Received: from smtp-out-130.synserver.de ([212.40.185.130]:1060 "EHLO smtp-out-120.synserver.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751473Ab2F1M0l (ORCPT ); Thu, 28 Jun 2012 08:26:41 -0400 X-SynServer-TrustedSrc: 1 X-SynServer-AuthUser: lars@metafoo.de X-SynServer-PPID: 6438 Message-ID: <4FEC4E62.3020101@metafoo.de> Date: Thu, 28 Jun 2012 14:30:26 +0200 From: Lars-Peter Clausen User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.4) Gecko/20120510 Icedove/10.0.4 MIME-Version: 1.0 To: Mark Brown CC: Takashi Iwai , alsa-devel@alsa-project.org, swarren@nvidia.com, linux-kernel@vger.kernel.org, Laxman Dewangan , lrg@ti.com, Marek Szyprowski Subject: Re: [alsa-devel] [PATCH] ASoC: snd_dmaengine: add common api for pcm_mmap References: <1340866886-24432-1-git-send-email-ldewangan@nvidia.com> <4FEC3B70.5030902@metafoo.de> <20120628121816.GB21029@sirena.org.uk> In-Reply-To: <20120628121816.GB21029@sirena.org.uk> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/28/2012 02:18 PM, Mark Brown wrote: > On Thu, Jun 28, 2012 at 02:15:38PM +0200, Takashi Iwai wrote: >> Lars-Peter Clausen wrote: > >>> to the ALSA core. Now that there is a generic dma_mmap_writecombine it may >>> make sense to integrate this with snd_pcm_lib_default_mmap. > >> Agreed. > >> Also, it must be portable. So far, only ARM has >> dma_mmap_writecombine(), thus the build on other arch would fail as >> is. > > Oh, dear - this means we don't actually have a generic API at all. Is > there any effort being made to make this generally available? Yes there is, and in fact in next/master there is generic dma_mmap_writecombine. I'm not quite sure how it behaves on non ARM archs though. But in theory it should fallback to a normal coherent mapping. Marek did a lot of work on this, I've put him on Cc. - Lars