[alsa-devel] ASOC: For SND_SOC_DAIFMT_IB_IF what is invert baseed on?

[Liam Girdwood]

On Sun, 2008-10-26 at 00:31 +0800, Richard Zhao wrote:
> Hi,
> 
> include/sound/soc.h
> /*
>  * DAI hardware signal inversions
>  */
> #define SND_SOC_DAIFMT_NB_NF            (0 << 8)        /* normal bclk + frm */
> #define SND_SOC_DAIFMT_NB_IF            (1 << 8)        /* normal bclk
> + inv frm */
> #define SND_SOC_DAIFMT_IB_NF            (2 << 8)        /* invert bclk
> + nor frm */
> #define SND_SOC_DAIFMT_IB_IF            (3 << 8)        /* invert bclk + frm */
> 
> What are frame cock and bit clock invert based on? I2S, PCM or some
> else bus protocols? Or just high level voltage or low level voltage?
> 

Generic logic levels (high/low voltage) that can apply to I2S and PCM
DAI's.

Liam