[alsa-devel] [PATCH 2/4] ASoC: SAMSUNG: Add I2S0 internal dma driver

Jassi Brar jassisinghbrar at gmail.com
Mon Jun 13 11:40:54 CEST 2011

On Mon, Jun 13, 2011 at 1:25 PM, Sangbeom Kim <sbkim73 at samsung.com> wrote:
> On Thu, Jun 10, 2011 at 7:08 PM, Jassi Brar wrote:
>> For my convenience, could you please tell how does it differ from my
>> original implementation?  Most things look same, except for a few
>> variables.
> Original code only can support specific buffer size and period count.
> New idma driver can work with various buffer size and multiple period.
I believe using flexible buffer and period size with secondary i/f
make sense only
when _system_ dma and memory is used. iDMA provides no benefit over system DMA.
Whereas for LPAM mode, you can _never_ get more power saving than using full
internal buffer with slightly smaller period size.
So IMHO iDMA driver should use the original approach, while system dma still
allows the user to have flexible buffer and period size for low
latency with sec i/f.

> And Original code is implemented it based on wrapper arch.
> But This patch can support driver arch.
Well, there was extra wrapper driver. This driver is mostly unchanged.

Frankly, I don't see enough changes to justify overriding the MODULE_AUTHOR.
Of course, the copyright belongs to Samsung still.


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