On Mon, Oct 25, 2021 at 11:52:04AM +0100, Mark Brown wrote:

On Sun, Oct 24, 2021 at 10:58:37AM +0200, Vincent Knecht wrote:

quoted

From: Stephan Gerhold <stephan@gerhold.net>

In some configurations it may be necessary to explicitly disable
the amplifier with an ALSA mixer. An example for this is a stereo
setup with two TFA989X. If only one of them should be used (e.g.
to use it as an earpiece) the other one must be explicitly disabled.

Add a virtual "Amp Switch" to implement that. There is no register
for this (SND_SOC_NOPM) so it only prevents DAPM from activating
the amplifier. Also it is inverted (= enabled by default) for
compatibility with devices that do not need this functionality.

Why can you not use a standard pin switch on the speaker output for
this?

Thanks for the suggestion! For some reason I was not aware of the pin
switch mechanism... :) We have tried this and it seems to work fine.
I will submit a separate series to allow setting up the pin switches
for the qcom sound cards instead.

The other patches in this series are independent of this one and still
apply cleanly for me. Can you just ignore PATCH 1/4 or would you prefer
a resend without this patch?

Thanks,
Stephan