Hi,
On Wed, Sep 30, 2015 at 9:08 PM, Anatol Pomozov anatol.pomozov@gmail.com wrote:
Hi
On Wed, Sep 30, 2015 at 11:10 AM, Mark Brown broonie@kernel.org wrote:
I don't think that's true, the expectation is that a left/right sample pair is time aligned so the left channel is definitely the start of frame for all meaningful purposes. It's certainly what I'd expect most people to understand - choosing a counterintuitive definition to make this one statement convenient is going to lead to constant confusion for the mode which is clearest.
To clarify, you propose following definition of normal FSYNC polarity:
- for I2S/left/right justified - frame starts with falling FSYNC edge
- for DSP A/B - frame starts with rising edge of FSYNC edge (plus offset)
- for AC97 my guess it is the same as DSP - frame starts with rising
FSYNC edge.
Is it correct?
Most CODEC datasheets describe the regular left/right justified formats as having the left channel starting on the rising edge of FSYNC, like for DSP A/B and AC'97. I²S is the only exception here.
Best regards, Benoît