[alsa-devel] [PATCH v2 1/2] ALSA: Add SoC on-chip internal memory support for DMA buffer allocation

[Takashi Iwai]

At Wed, 16 Oct 2013 17:34:45 +0800,
Nicolin Chen wrote:
> --- a/sound/core/pcm_native.c
> +++ b/sound/core/pcm_native.c
> @@ -3201,12 +3201,18 @@ int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
>  	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
>  #ifdef ARCH_HAS_DMA_MMAP_COHERENT
>  	if (!substream->ops->page &&
> -	    substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
> +	    substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV) {
>  		return dma_mmap_coherent(substream->dma_buffer.dev.dev,
>  					 area,
>  					 substream->runtime->dma_area,
>  					 substream->runtime->dma_addr,
>  					 area->vm_end - area->vm_start);
> +	} else if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_IRAM) {
> +		area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
> +		return remap_pfn_range(area, area->vm_start,
> +				substream->dma_buffer.addr >> PAGE_SHIFT,
> +				area->vm_end - area->vm_start, area->vm_page_prot);
> +	}

Here is a wrong place to put.  The handling of SNDRV_DMA_TYPE_IRAM
must be irrelevant with the existence of dma_mmap_coherent(), thus it
should be outside the ifdef block.

In addition, you need the check whether SNDRV_DMA_TYPE_DEV_IRAM !=
SNDRV_DMA_TYPE_DEV.


thanks,

Takashi