[Gta04-owner] Status

Dr. H. Nikolaus Schaller hns at goldelico.com
Fri Sep 2 10:42:26 CEST 2011

Am 02.09.2011 um 10:23 schrieb John Ogness:

> On 2011-09-02, Dr. H. Nikolaus Schaller <hns at goldelico.com> wrote:
>>> 2. OPTION GTM601
>>> we have not yet had success to access the PCM interface
>>> from the Linux side. The problem is that we don't understand
>>> ALSA SoC good enough to add a separate McBSP channel
>>> that either becomes visible as a separate sound card or
>>> as another channel or subdevice of the existing sound card
>>> for Earpiece, Microphone etc.
>>> If there is someone on this list who is knowledgable about
>>> the ALSA SoC architecture and drivers, please let's discuss.
>> Here we still need some support.
> I have done some work with audio drivers for OMAP3530 boards. I do not

That is great!

> have much free time available, but maybe I can help out here.

We just need some recommendations about the best approach
and maybe do some code review. Or some sample code how to
enable/use a second McBSP channel would also help.

> Are we talking about multiple codecs connected to different McBSP
> channels? Where do I find the board layout documents showing the chips
> and their connections to the OMAP SOC?

They are not yet published but will be soon.
For the moment let's assume that the McBSPs are wired correctly.

The main assignment is:

McBSP1		FM Transceiver PCM
McBSP2		TPS65650 (driver works as sound card #0)
McBSP3		Bluetooth PCM
McBSP5		n/a (used as GPIOs)

So the problem we face is that we
1. have to decide if FM/BT/Telephony are presented as /separate/ sound cards
2. or are /additional channels/ of the TWL4030 driver i.e. sound card #0

The current state of our code is that we have decided for 1. (because not
knowing better) and added a new SoC-codec (copied and modified code
from some Wolfson coded) for the GTM601.

What we have not managed is to make the codec driver becomes visible
as a second sound card, although it gets loaded. The TWL codec works

I.e. we are not at the point to test/check any McBSP connectivity.

Would a git patch help to analyse and comment what we have tried to


More information about the Gta04-owner mailing list