[alsa-devel] [PATCHv2] ASoC: samsung: pass DMA channels as pointers

Krzysztof Kozlowski k.kozlowski at samsung.com
Wed Nov 18 02:33:41 CET 2015


On 18.11.2015 00:53, Arnd Bergmann wrote:
> ARM64 allmodconfig produces a bunch of warnings when building the
> samsung ASoC code:
> 
> sound/soc/samsung/dmaengine.c: In function 'samsung_asoc_init_dma_data':
> sound/soc/samsung/dmaengine.c:53:32: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
>    playback_data->filter_data = (void *)playback->channel;
> sound/soc/samsung/dmaengine.c:60:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
>    capture_data->filter_data = (void *)capture->channel;
> 
> We could easily shut up the warning by adding an intermediate cast,
> but there is a bigger underlying problem: The use of IORESOURCE_DMA
> to pass data from platform code to device drivers is dubious to start
> with, as what we really want is a pointer that can be passed into
> a filter function.
> 
> Note that on s3c64xx, the pl08x DMA data is already a pointer, but
> gets cast to resource_size_t so we can pass it as a resource, and it
> then gets converted back to a pointer. In contrast, the data we pass
> for s3c24xx is an index into a device specific table, and we artificially
> convert that into a pointer for the filter function.
> 
> Signed-off-by: Arnd Bergmann <arnd at arndb.de>
> ---
> v2:
> 
> - no longer clash with SPI patch
> - don't reference platform data that might be NULL
> 

Looks good:

Reviewed-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>

Best regards,
Krzysztof



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