HDMI audio with kernel 4.8

Hi all,

Is it possible to configure HDMI audio on the BeagleBoneBlack using a v4.8 stock Linux kernel?

I’m working with custom hardware that is based on the BBB schematic and stock Linux v4.8. The HDMI circuit is intentionally similar - the DRM and McASP pins from the Sitara are connected to a tda19988. We have HDMI video working, actually, but I’m struggling to configure the audio. Still learning…

We’re largely based on this dts with the McASP pins adjusted to use McASP1 instead of McASP0 per the custom hardware.

I’ve noticed that the tda998x driver in kernel v4.8 doesn’t support the audio-ports setting. Is there another way to configure the audio?

I’ve tried duplicating the above BBB overlay’s settings but have found that snd_soc_get_dai_name() fails because it can’t find the tda19988 in the component_list. Specifically, it defers the probe multiple times and eventually gives up. Perhaps there is another setting the device tree that will add the tda19988 to the DAI list?

I’ve been experimenting with configuring a simple-audio-card with a dummy audio codec using the snd-soc-dummy driver. It looks like the snd-soc-dummy driver doesn’t have any device tree bindings in kernel v4.8, but it seems possible to patch them in. However, I’m not sure that this is the right way to go.

Perhaps there’s a different approach entirely?

Thanks for your help,


hdmi took for ever to get in mainline... sadly in 4.9.x


Here are some reference commits..


Hi Robert,

Ok, we’ll work on upgrading.

I appreciate the reference and the quick response. I’d seen quite a bit of audio functionality land in 4.9.x but wasn’t sure if it was required - it can be challenging to prove a negative.