[PATCH v3 3/4] media: videobuf2-dma-contig: use dma_mmap_coherent if available

Hideki EIRAKU hdk at igel.co.jp
Thu Aug 16 06:13:58 EDT 2012


Hello,

From: Marek Szyprowski <m.szyprowski at samsung.com>
Subject: RE: [PATCH v3 3/4] media: videobuf2-dma-contig: use dma_mmap_coherent if available
Date: Tue, 07 Aug 2012 16:53:25 +0200

> I'm sorry for bringing this issue now, once you have already created v3 of your
> patches, but similar patch has been already proposed some time ago. It is already
> processed together with general videobuf2-dma-contig redesign and dma-buf extensions
> by Tomasz Stanislawski.
> 
> See post http://thread.gmane.org/gmane.comp.video.dri.devel/70402/focus=49461 and
> http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/49438 
> 
> It doesn't use conditional code inside videobuf2 allocator and rely entirely on 
> dma-mapping subsystem to provide a working dma_mmap_coherent/writecombine/attrs() 
> function. When it was posted, it relied on the dma-mapping extensions, which now
> have been finally merged to v3.6-rc1. Now I wonder if there are any architectures, 
> which don't use dma_map_ops based dma-mapping framework, which might use 
> videobuf2-dma-conting module. 

Thank you for telling me about videobuf2-dma-contig and v3.6-rc1.  The
videobuf2-dma-contig patch I sent is now unnecessary.  So I will
remove the patch.  I will remove the patch defining
ARCH_HAS_DMA_MMAP_COHERENT too because the v3.6-rc1 kernel has generic
dma_mmap_coherent() API for every architecture.

I will also remove the Laurent's patch I sent because it was related
to ARCH_HAS_DMA_MMAP_COHERENT.

The remaining patch is sh_mobile_lcdc.  I will remove ifdefs from the
patch and re-post it as a patch v4.

-- 
Hideki EIRAKU <hdk at igel.co.jp>



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