On Tue, Dec 07, 2010 at 11:29:15AM +0200, Peter Ujfalusi wrote:
Fair enough. I did taken a look at the possibility to do the register update between DAPM power down and up, but I thought it is a bit big change (the place, where the DAPM power down and up happens is quite deep, and I was not sure how to inject things between those).
Stash the callback in the DAPM context - we have to lock the context to do the path walks anyway so no issue with reentrancy.
If we do the update at the same time (or around), when the power for the switch would have been enabled, than we are filtering the switching for the DAPM widgets before the switch.
On the other hand it's possible that this will result in a sharp switch in of a DC offset rather than a slow ramp, and anything doing DC offset correction is going to want its input to be up before correcting.