At Mon, 08 Jan 2007 10:37:40 -0500,
David Cullen wrote:
>
> Dear Mr. Iwai,
>
> Takashi Iwai wrote:
> > The implementation depends pretty much on the architecture.
> > (Also, dma_mmap() is no global function but specific only for ARM.)
> > Since the vm_region struct is different between ppc and arm (the page
> > pointer is missing in ppc version), it cannot be copied as it is.
> >
> > A simple (but totally untested) version would be like below:
> >
> > int dma_mmap_coherent(struct device *dev,
> > struct vm_area_struct *vma, void *cpu_addr,
> > dma_addr_t dma_addr, size_t size)
> > {
> > unsigned long pfn;
> >
> > pfn = page_to_pfn(virt_to_page(bus_to_virt(dma_addr)));
> > vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
> > return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
> > vma->vm_end - vma->vm_start,
> > vma->vm_pgprot);
> > }
> >
> > (This might not work for some ppc models, though...)
> >
> > Then either add .mmap callback to each of snd_pcm_ops table in ca0106
> > that calls dma_mmap_coherent() above, or change snd_pcm_default_mmap
> > to call dma_mmap_coherent() directly instead of nopage method.
> > For the former way, take a look at sound/arm/aaci.c (and devdma.c) as
> > a reference.
> >
>
> I implemented the "former way". However, when I put a breakpoint in
> __dma_alloc_coherent it does not get called when I run speaker-test.
> It does get called during execution of "modprobe snd-ca0106".
You mean change ca0106 codes to add dma_alloc_coherent() as mmap
callback? Then please show the patch you changed. It's easier to
check.
Takashi
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys - and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
Alsa-devel mailing list
Alsa-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/alsa-devel
