Question regarding HDMI Audio support on i.MX6 with vanilla kernel

[Russell King - ARM Linux]

On Mon, Nov 06, 2017 at 02:32:19PM +0000, Luís Mendes wrote:
> Thanks for the replies!
> 
> Russell, the profile you sent me, did help, it was indeed missing. Now I
> have Digital Stereo (HDMI) Output and Digital Stereo (IEC958) Output
> besides the one I already had for this sound card (Analog Stereo Output).
> 
> Unfortunately I still get no sound on HDMI, neither on IEC958 optical
> output, although the laser led lit up when I set the output to IEC958, but
> no sound on neither outputs.
> 
> I have rechecked the kernel configuration of linux-4.14-rc5, but I don't
> find anything wrong with it... I am testing with the Wandboard Quad Plus.

I'd suggest as a first step getting rid of every other sound capable
device apart from the dw-hdmi driver.

Next, try playing an audio file with aplay:

aplay -D front:CARD=DWHDMI,DEV=0 some.wav

You may have to disable your sound daemon for that to work.

Check /proc/interrupts, see whether the interrupt count for 120000.hdmi
increases when you play an audio file.

Then try via the sound daemon.

Let me know how you get on.

-- 
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