[wdmaudiodev] Re: AVStream Mixer Problems
- From: "DJ Sisolak" <dsisolak@xxxxxxxxxxxxxxxxxxxxxx>
- To: <wdmaudiodev@xxxxxxxxxxxxx>
- Date: Thu, 26 Aug 2004 09:03:45 -0700
Hello Mat & John,
You are correct in that the avcaudio driver in XP was not very robust.
The central reason for that is that the only device available
commercially at the time of XP release to test against, which was the
Sony Lissa system. Therefore it was not so much a class driver as it was
a Lissa driver. I have since re-written the driver but as of yet have
not had a release vehicle for it. It "should" be part of the Longhorn
release as part of UAA. However I do not make those decisions. The key
to its release, as always, is finding a set of class compliant devices
to test against. Of course the decision to do anything for downlevel
support is not mine either. (If anyone is interested in working with the
class driver please contact me (dsisolak@xxxxxxxxxxxxx) or
hakons@xxxxxxxxxxxxx on a separate thread. We need as many test
platforms as we can get :-))
As to setting the kmixer volume via the driver, I agree with Mat. If you
do not want a volume or mute control on the device and only wish to use
the volume control in the system mixer, simply do not put them in your
topology. Connect the destination plug in the subunit directly to the
source plug. Or am I missing the point?
DJ
This posting is provided "AS IS" with no warranties, and confers no
rights
________________________________
From: wdmaudiodev-bounce@xxxxxxxxxxxxx
[mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Mathieu Routhier
Sent: Thursday, August 26, 2004 7:05 AM
To: wdmaudiodev@xxxxxxxxxxxxx
Subject: [wdmaudiodev] Re: AVStream Mixer Problems
John and DJ,
The last time I worked on a device including an AVC audio subunit (last
winter), we faced the same problems as John described. The avcaudio
crashed when it loaded. Using the debugger and correct symbols, we
determined that the crash occurred while parsing the descriptor. Even
if the error was in the descriptor we crafted, I guess the driver
shouldn't have crashed. If I remember correctly, we reported that issue
to MS and it probably reached you, DJ, am I wrong? In any case, we
ended up writing our own avcaudio replacement driver for numerous
reasons, one of them being the driver for our device had to do things
that avcaudio was not designed for. Nevertheless, we used AVC.sys to
handle avc commands because we had a minimum requirement of Windows XP.
About your master volume question... Well, one thing you could do is
simply do not declare a master volume control. The other lines (midi,
wave, CD, etc) should still show up. Alternatively, you could implement
your own software attenuator. I am not sure you can "ask" kmixer to add
a master volume control.
Mat
________________________________
From: wdmaudiodev-bounce@xxxxxxxxxxxxx
[mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of John D. Farmer
Sent: Wednesday, August 25, 2004 6:05 PM
To: wdmaudiodev@xxxxxxxxxxxxx
Subject: [wdmaudiodev] Re: AVStream Mixer Problems
To answer DJ's question: My device does Implement the AVC Audio subunit
spec. We originally tried to use AVCAudio.sys after modifying the INF
and trying to install it, it not only crashed our test machine but hosed
our registry beyond any ability to repair.
We tried to use 61883.sys and AVC.sys, but there we're quirks in both of
those drivers that wouldn't allow us to get the card initialized
properly. I believe we also had problems sending data down to the bus.
The final problem was that we needed support for Windows 2000 (I believe
AVC wasn't supported on except in MSDV.sys). The long story short, I
ended up crafting my own psuedo AVC.sys by sending down raw Isochronous
commands to the 1394 bus and getting the response back in a allocated
address range. I only included selective AVC command specific to our
hardware.
Finally this is probably a rather stupid question, but is there any way
to use my Volume Control to send the volume and mute values to the
KMIXER lines so that KMIXER can take care of mixing the audio stream
instead of having to set the hardware to those volume values (it seems
the new chip we are working with does not yet support the Audio Subunit
FUNCTION_BLOCK command, so I don't think the hardware can set the volume
right now anyway).
Thanks again for your time,
John
----- Original Message -----
From: Mathieu Routhier <mailto:mrouthier@xxxxxxxxxxxxx>
To: wdmaudiodev@xxxxxxxxxxxxx
Sent: Wednesday, August 25, 2004 1:45 PM
Subject: [wdmaudiodev] Re: AVStream Mixer Problems
Oh. One more thing:
In my experience, sysaudio will set a volume value and verify it
has been successfully set by querying the value right afterwards. If it
gets confused by seeing that the value is not set as required, after a
few tries, it will ultimately give up and disable the control. I don't
know the exact algorithm but that's what I've witnessed.
Mat
________________________________
From: wdmaudiodev-bounce@xxxxxxxxxxxxx
[mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of DJ Sisolak
Sent: Wednesday, August 25, 2004 3:50 PM
To: wdmaudiodev@xxxxxxxxxxxxx
Subject: [wdmaudiodev] Re: AVStream Mixer Problems
Hi John,
I would like to add to Mathieu's comments that if the support
handler does not return the expected structures and simply returns
success as you say, then the control will likely not function as well.
On a side note, does your device implement the AV/C Audio
subunit spec?
Thx,
DJ
This posting is provided "AS IS" with no warranties, and confers
no rights
________________________________
From: wdmaudiodev-bounce@xxxxxxxxxxxxx
[mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Mathieu Routhier
Sent: Wednesday, August 25, 2004 11:35 AM
To: wdmaudiodev@xxxxxxxxxxxxx
Subject: [wdmaudiodev] Re: AVStream Mixer Problems
John,
Obviously, if your hardware needs a message to change its volume
value, yes you need to send a message to it. Maybe I misunderstood the
question?
About the second question, yes, these controls are inserted by
kmixer/sysaudio. I would suggest you implement volume control on your
master volume and leave the other controls untouched. The inputs from
those lines are mixed directly into your audio device, so you couldn't
differentiate these feeds even if you wanted to. And for the balance
control, this translates to volume commands; so you don't really need to
do anything special for this to work, other than supporting a stereo
volume commands.
Mat
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