From mboxrd@z Thu Jan 1 00:00:00 1970 From: Clemens Ladisch Subject: Re: [alsa-devel] [PATCH] ASoC: snd_dmaengine: add common api for pcm_mmap Date: Thu, 28 Jun 2012 14:32:33 +0200 Message-ID: <4FEC4EE1.1030001@ladisch.de> References: <1340866886-24432-1-git-send-email-ldewangan@nvidia.com> <4FEC3B70.5030902@metafoo.de> <20120628121816.GB21029@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120628121816.GB21029@sirena.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: Mark Brown Cc: Takashi Iwai , alsa-devel@alsa-project.org, Lars-Peter Clausen , swarren@nvidia.com, linux-kernel@vger.kernel.org, Laxman Dewangan , lrg@ti.com List-Id: alsa-devel@alsa-project.org Mark Brown wrote: > On Thu, Jun 28, 2012 at 02:15:38PM +0200, Takashi Iwai wrote: >> 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? http://lkml.org/lkml/2012/6/15/27: | Commit 9adc5374 ('common: dma-mapping: introduce mmap method') added a | generic method for implementing mmap user call to dma_map_ops structure. | | This patch converts ARM and PowerPC architectures (the only providers of | dma_mmap_coherent/dma_mmap_writecombine calls) to use this generic | dma_map_ops based call and adds a generic cross architecture | definition for dma_mmap_attrs, dma_mmap_coherent, dma_mmap_writecombine | functions. | | The generic mmap virt_to_page-based fallback implementation is provided for | architectures which don't provide their own implementation for mmap method. | | Signed-off-by: Marek Szyprowski | Reviewed-by: Kyungmin Park | --- | Hello, | This patch is a continuation of my works on dma-mapping cleanup and | unification. Previous works (commit 58bca4a8fa ('Merge branch | 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping') | has been merged to v3.4-rc2. Now I've focuses on providing implementation | for all architectures so the drivers and some cross-architecture common | helpers (like for example videobuf2) can start using this new api. | | I'm not 100% sure if the PowerPC changes are correct. The cases of | dma_iommu_ops and vio_dma_mapping_ops are a bit suspicious for me, but I | have no way to test and check if my changes works for that hardware. | | Best regards | Marek Szyprowski | Samsung Poland R&D Center Regards, Clemens