[alsa-devel] ASoC and a codec that can't be controlled
lg at opensource.wolfsonmicro.com
Wed May 23 17:37:57 CEST 2007
On Tue, 2007-05-22 at 10:47 -0500, Timur Tabi wrote:
> I'm working on some ASoC drivers for a new board, and we're using a CS4270. The CS4270 is
> interesting in that if it is connected in stand-alone mode, there is no way to configure
> it. The board wirings determine all the parameters.
> Therefore, my CS4270 codec driver will probably be very skimpy.
> My question is: does this mean that my cs4270.c file will *never* call these functions:
These functions are only required in the codec driver to change volume,
mixer settings etc. If your codec has no volume or mixers then you don't
These are used for setting up the dynamic audio power management and
won't be needed in stand alone mode.
> These are the functions used to add new controls and widgets.
> So how does ALSA know that it needs to call my I2S driver *instead* of my codec driver to
> do stuff like change volume?
You probably want to create a volume kcontrol in your I2S driver. I
assume your I2S controller can digitally adjust the volume by altering
the PCM stream ? The kcontrols can be added in your I2S driver probe
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