[PATCH V4 0/2] Add DT support for i2s

Padma Venkat padma.kvr at gmail.com
Mon Dec 10 06:00:50 EST 2012


Hi Mark,

On Sun, Dec 9, 2012 at 12:56 PM, Mark Brown
<broonie at opensource.wolfsonmicro.com> wrote:
> On Sat, Dec 08, 2012 at 10:07:54AM +0530, Padma Venkat wrote:
>
>> Samsung i2s driver registers the platform device twice one for the
>> samsung-i2s.0,1 or 2 and two for samsung-i2s.4(which actually doesn't
>> represent any H/W peripheral). The max number of I2S blocks on any
>> Samsung SoC are 3, the secondary device registration starts with
>> device number 4.The second time registration is for the secondary fifo
>> interface of a CPU dai if any exists.
>
>> With DT support the device number in the driver is always -1, I used
>> alias id for the above purpose.
>
> So, the thing here is that while the numbers were totally OK for
> platform device use they really don't fit into DT at all well.  I think
> the thing here is to either have a node for the second CPU side DAI or
> to have a single DT link automatically expanded into two DAI links.  I
> think the second option is much better - there's only one link on the
> board, it just happens to get expanded into two the way things are
> currently implemented in ASoC.

Could you please explain me in more detail about "single DT link
automatically expanded into two DAI links".
How this can be done?

>
> This stuff probably also ought to be moved over to soc-pcm as well by
> the way.
Thanks
Padma



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