[alsa-devel] [PATCHv2 5/7] ASoC: TWL6030: Add support for low-power mode

[Mark Brown]

On Tue, Oct 13, 2009 at 03:15:45PM -0500, Lopez Cruz, Misael wrote:

> From TWL6030 CODEC driver pespective, the DAI link supported rate
> should be 48kHz or 96kHz? If the final goal is to explicitly represent
> all links in the system (ABE, Phoenix, McBSP, etc), then ABE link
> should expose somehow that it delives upsampled data. If that assumption
> is true, then TWL6030 DAI should support 96kHz.

Yes, that sounds like the way to go.

> A second concern is that runtime constraints will prevent rates
> supported by the system, when the constraints are only valid for the
> link. For example, if the TWL6030 CODEC adds a contraint for 96kHz,
> then it prevents the whole system to play 48kHz, which is supported
> when ABE is enabled since ABE upsamples it.

Initially I'd say that we should only represent the requirements on each
end of a given link and make the devices responsible for imposing
constraints that come from routing between two interfaces.  We'd need to
see how all this works in practice, though.