MXS: How to configure SGTL5000 ASoC as master?

MXS: How to configure SGTL5000 ASoC as master?

[Lauri Hintsala]

Hi,

SGTL5000 ASoC is hard coded to be slave in sound/soc/mxs/mxs-sgtl5000.c. 
In our HW design mclk of ASoC is sourced from external oscillator. 
Because of our design ASoC should be configured as master. In that case 
master clock of SAIF should be disabled.

Is there any plan to have configuration for mxs-sgtl5000 driver? What is 
preferred way to solve this issue?

BR,
Lauri Hintsala

p.s. I resent this mail because I wasn't subscriber of alsa-devel 
mailing list.

Re: How to configure SGTL5000 ASoC as master?

[Dong Aisheng-B29396]

> -----Original Message-----
> From: Lauri Hintsala [mailto:lauri.hintsala@bluegiga.com]
> Sent: Tuesday, January 10, 2012 2:20 PM
> To: Dong Aisheng-B29396
> Cc: alsa-devel@alsa-project.org; linux-arm-kernel@lists.infradead.org
> Subject: MXS: How to configure SGTL5000 ASoC as master?
> Importance: High
> 
> Hi,
> 
> SGTL5000 ASoC is hard coded to be slave in sound/soc/mxs/mxs-sgtl5000.c.
Yes, Saif TX can only work on master mode so we simply only support master mode
for both saif rx/tx.

> In our HW design mclk of ASoC is sourced from external oscillator.
> Because of our design ASoC should be configured as master. In that case master
IIRC using external mclk does not mean sgtl5000 has to be master.
And as I said above, saif tx can only be master, that's a hw limitation.

> clock of SAIF should be disabled.
> 
You can leave it there without using it.

> Is there any plan to have configuration for mxs-sgtl5000 driver? What is
> preferred way to solve this issue?
> 
We can extend the mxs-sgtl5000 driver to support external mclk.
(but sgtl5000 as master mode is not supported).
I did not have time to do it recently, also I did not have such board.
If somebody wants to do it I will be happy to review.

> BR,
> Lauri Hintsala
> 
> p.s. I resent this mail because I wasn't subscriber of alsa-devel mailing list.

Regards
Dong Aisheng

Re: How to configure SGTL5000 ASoC as master?

[Lauri Hintsala]

On 01/10/2012 08:43 AM, Dong Aisheng-B29396 wrote:
>> SGTL5000 ASoC is hard coded to be slave in sound/soc/mxs/mxs-sgtl5000.c.
> Yes, Saif TX can only work on master mode so we simply only support master mode
> for both saif rx/tx.

You are right. I didn't notice that before. Thanks.

Lauri