Revised HDMI Audio Patch For RadeonHD Driver

[bulletxt]

out-of-the-box support for 2d and 3d on almost any recent distribution?

what? I think you've seen to many cows flying in the sky.

[Deathsimple]

Nice job! I'll be trying it soon!

Anyone know if this driver will still enable audio after a VT switch? The previous version would stop working (the audio part) after switching back and forth to the console.

Thanks, and yes the VT switching bug was fixed some time ago.

yeah, having video driver in order to use hdmi audio device seems...wrong. somehow.

I should really start a wiki about this patch and HDMI in generall:
HDMI uses the spare bandwidth in the horizontal and vertical video sync to transmit additional data, like audio or info packets.

Getting the audio data from the application and stuffing it into packets is the job of alsa. Programming the hardware to mix those packets into the video data is the job of my patch. Alsa simply can't to this, because you need to know what's the pixel clock (the display resolution) of the current video mode.

And yes, i think kernel mode setting would be a better way doing this.

At what level of support does it offer? Does it support multichannel LCPM HDMI audio? With protected content playback coming with a future ATI blob will it be able to handle PAP as well or is everything going to be downsampled?

What's currently tested is 16/20/24 bits per sample at 32/44,1/48 kHz sampling rate. Additional sampling rates like 88,2/96 kHz should work, but aren't tested yet.

Multichannel output and AC3/DTS path through won't work at the moment do to limitations on the alsa side. The latest alsa beta 1.0.18rc2 introduce multichannel output, but i don't have the hardware to test this, if you want to volunteer just PM me.

About the content protection, in my opinion that's nothing more than marketing. The HDMI Standard states clearly that if content protection should be used is up to the source device, which in this case the x driver controls.

When will AMD release 3D specs for R600/R700?

This was actually released some time ago, and the fact that everything was reverse engineered isn't 100% true, i have pretty good documentation about the audio/alsa stuff, but nearly no docs about the HDMI packet mixer.

Bye, Christian.