Re: [PATCHv2 3/3] ASoC: samsung: pass filter function as pointer

From: Krzysztof Kozlowski
Date: Tue Nov 17 2015 - 21:14:00 EST

On 18.11.2015 00:55, Arnd Bergmann wrote:
> As we are now passing the filter data as pointers to the drivers,
> we can take the final step and also pass the filter function the
> same way. I'm keeping this change separate, as there it's less
> obvious that this is a net win.
> Upsides of this are:
> - The ASoC drivers are completely independent from the DMA engine
> implementation, which simplifies the Kconfig logic and in theory
> allows the same sound drivers to be built in a kernel that supports
> different kinds of dmaengine drivers.
> - Consistency with other subsystems and drivers
> On the other hand, we have a few downsides:
> - The s3c24xx-dma driver now needs to be built-in for the ac97 platform
> device to be instantiated on s3c2440.
> - samsung_dmaengine_pcm_config cannot be marked 'const' any more
> because the filter function pointer needs to be set at runtime.
> This is safe as long we don't have multiple different DMA engines
> in thet same system at runtime, but is nonetheless ugly.
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> v2: avoid possibly NULL pdata

Looks good.

I also tested entire patchset on Exynos4412/Trats2 board (custom kernel
with audio working) for regressions and it worked fine. However, since
this was not a S3C24xx/S3C64xx board, I don't find that testing
sufficient for a tag. So only:

Reviewed-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>

Best regards,

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