[alsa-devel] [PATCH 0/5] ASoC: meson: add hdmitx glue support

[Kevin Hilman]

Jerome Brunet <jbrunet at baylibre.com> writes:

> On the Amlogic SoC, there is a glue between the SoC audio outputs and the
> input of the embedded Synopsys HDMI controller.
>
> On the g12a, this glue is mostly a couple of muxes to select the i2s and
> spdif inputs of the hdmi controller. Each of these inputs may have
> different hw_params and fmt which makes our life a little bit more
> interesting, especially when switching between to active inputs.
>
> This glue is modeled as codec driver and uses codec-to-codec links to
> connect to the Synopsys controller. This allows to use the regular
> hdmi-codec driver (used by dw-hdmi i2s).
>
> To avoid glitches while switching input, the trick is to temporarily
> force a disconnection of the mux output, which shutdowns the output dai
> link. This also ensure that the stream parameters and fmt are updated
> when the output is connected back.

Tested-by: Kevin Hilman <khilman at baylibre.com>