Linux 2.6.33-rc4 Kernel: 40% DRM Changes

[drag]

So, what am I doing wrong? Is there anything else which is needed to utilize this gem of code?

What are you using to manage PA?

[HokTar]

Just the regular stuff called "Sound preferences" (right-click on the icon in the tray). Then in the output tab I can (theoretically) switch between the outputs.

[drag]

Yeah.

I just wondering how much PA knew about your hardware. It has the ability to go and configure your hardware's mixers. This is meant to replace the need for users to opening up a terminal and running 'alsamixer' to configure the hardware.

This is a feature of newer versions of PA.

If Ubuntu uses a slightly older version or if the programmers were not aware of how to work your sound card at the time they made that version then PA probably won't know how to configure your hardware correctly.

Usually sound cards support multiple outputs... like headphones, stereo out, digital out, surround sound, etc etc. That is a huge PITA to configure manually and PA can do it correctly for you if it understands the hardware.

If you in sound preferences then you can choose between different sound outputs in the 'hardware tab' and 'output tabs'.


In that case that PA does not know how to configure your hardware correctly you'll probably have to it manually and fire up 'alsamixer' on the command line and configure the low-level mixers for your hardware so they work.

My first guess is just that the HDMI audio out is muted.
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I know going back to muck around with alsa stuff directly is a huge pain in the ass once your used to dealing with PulseAudio, but it is not too difficult once you know what to expect. A throw back to the 'bad old days' of 'just alsa'.

First you need to figure out what card is what. Since you have more then one card then you'll have to use alsamixer to figure out what is what.

This can change in between reboots depending on how you have stuff plugged in. Depending on udev, the order they are detected, and all that.


alsamixer -c0

will access the first card.

alsamixer -c1 will acess the second card.

etc etc.

Don't be surprised if you end up with more then 2 'sound cards'. There are all sorts of virtual sound devices that show up as sound cards to the user. For example I had a webcam with mic input and that showed up as a sound device.

For testing sound as you play around with the hardware mixers I like to use 'mplayer'.

mplayer -ao alsa:device=hw=0 *mp3

will have mplayer output to the first sound card and

mplayer -ao alsa:device=hw=1 *mp3

Will output to the second.


I like having this play while I muck around with the mixers. Make sure no other device is playing music. Typically modern hardware is only able to handle one PCM stream at a time and if you have something playing over PA then it may block access to the hardware.

If that is a problem you can probably disable PA by going into gnome-session-properties and unchecking it and logging out and logging back in. Run 'killall pulse-audio' to make sure that it is dead. Depending on how Gnome is setup PA may auto-respawn otherwise.


If you get sound output working correctly then Alsa should save the settings and it should work fine with PA after that.

Sorry, but that is about the best I can do. I don't have any HDMI devices to test it out on right now otherwise I'd have more of a better step-by-step solution.

[HokTar]

Thanks for your exhaustive reply.

I did try playing a file with mplayer using alsa outputs. The azalia chip worked, the hdmi remained silent while PA reported it playing sound.
It was not muted in any obvious places, though alsa sometimes has nice tricks.

Unfortunately I can't test it right away, only when I travel home, but I don't have internet access there. Point is that me not writing back here for a few days is not out of lack of interest, but impossibility.

[agd5f]

Hdmi audio has to be enabled in the video stream by the GPU driver. Currently you need radeonhd or 2.6.33 for kms. In both cases support is still experimental.

[HokTar]

Hdmi audio has to be enabled in the video stream by the GPU driver. Currently you need radeonhd or 2.6.33 for kms. In both cases support is still experimental.

I have a test system for this:
2.6.33rc4
mesa7.7 (xorg-edgers)

Are these not recent enough? In fact kms, compiz, etc. works like a charm without any kind of tearing.

[tball]

I have a test system for this:
2.6.33rc4
mesa7.7 (xorg-edgers)

Are these not recent enough? In fact kms, compiz, etc. works like a charm without any kind of tearing.

I can't tell you why it isn't working. But what I can tell you is, that it probably isn't PA's fault.

I had problems with the oss hdmi drivers too (git everything), but with fglrx it works fine (PA here also). So conclusively PA is handling hdmi audio just fine.

[agd5f]

I have a test system for this:
2.6.33rc4
mesa7.7 (xorg-edgers)

Are these not recent enough? In fact kms, compiz, etc. works like a charm without any kind of tearing.

As I said oss hdmi audio support is experimental at the moment. Also, there's no support for r7xx hdmi audio in KMS yet IIRC.

[HokTar]

Also, there's no support for r7xx hdmi audio in KMS yet IIRC.

Then it's my fault, after reading [1] I assumed that it should be working.

[1] http://www.phoronix.com/scan.php?pag...item&px=NzgxMA