Re: Noob looking to work on HDMI audio integration

[Tanel Kriik]

On Sun, Apr 16, 2017 at 5:54 PM, Jonathan Gray  wrote:
> The hdmi codecs were disabled in azalia as non working audio devices
> would attach as audio0 with the real audio device attaching as audio1.
> This meant symlinks in /dev had to change or programs had to explicitly
> use /dev/audio1 etc instead of /dev/audio.

I see. Could azalia determine which codecs work and which do not
at the time of attachment? Alternatively, would it be reasonable
to prefer codects in order of: 1. analog, 2. digital and 3. HDMI
during attachment, instead of skipping HDMI altogether?

Re: Noob looking to work on HDMI audio integration

[Jonathan Gray]

On Sun, Apr 16, 2017 at 05:04:49PM +0300, Tanel Kriik wrote:
> Hi, total newbie here:
> 
> I have intermediate C experience from work and free time,
> and use OpenBSD more or less often.
> I'm familiar with the OpenBSD coding style and have compiled the
> kernel a few times,
> but I haven't dabbled deeper than that.
> 
> Areas I'm surely lacking in:
> 
> * Audio processing (only know the basics of DSP)
> * Drivers
> * OpenBSD development workflow (modify, compile, test cycle - how do you do 
> it?)
> 
> I guess I'd need to at least get to know the azalia(4) driver and how
> it interfaces with
> lower-level drivers in the system?
> 
> On the other hand, if it was easy, then someone would've already done it?
> 
> I'd like to hear from more experienced people here if this would be at least
> realistically doable by someone at my level.
> Has this been attempted before but stopped due to some inherent obstacles?
> 
> I browsed azalia.c and found that for some reason HDMI codecs are disabled,
> but I don't remember seeing an exact explanation as to why it was done from 
> the
> CVS logs (might have overlooked something though). Does it have something
> to do with the internal mixers in graphics cards or something similar?
> 
> Thanks
> 

The hdmi codecs were disabled in azalia as non working audio devices
would attach as audio0 with the real audio device attaching as audio1.
This meant symlinks in /dev had to change or programs had to explicitly
use /dev/audio1 etc instead of /dev/audio.

Noob looking to work on HDMI audio integration

[Tanel Kriik]

Hi, total newbie here:

I have intermediate C experience from work and free time,
and use OpenBSD more or less often.
I'm familiar with the OpenBSD coding style and have compiled the
kernel a few times,
but I haven't dabbled deeper than that.

Areas I'm surely lacking in:

* Audio processing (only know the basics of DSP)
* Drivers
* OpenBSD development workflow (modify, compile, test cycle - how do you do it?)

I guess I'd need to at least get to know the azalia(4) driver and how
it interfaces with
lower-level drivers in the system?

On the other hand, if it was easy, then someone would've already done it?

I'd like to hear from more experienced people here if this would be at least
realistically doable by someone at my level.
Has this been attempted before but stopped due to some inherent obstacles?

I browsed azalia.c and found that for some reason HDMI codecs are disabled,
but I don't remember seeing an exact explanation as to why it was done from the
CVS logs (might have overlooked something though). Does it have something
to do with the internal mixers in graphics cards or something similar?

Thanks