[wdmaudiodev] Re: AVStream Mixer Problems

  • From: Harry Graham <harry_graham@xxxxxxxxxx>
  • To: "'wdmaudiodev@xxxxxxxxxxxxx'" <wdmaudiodev@xxxxxxxxxxxxx>
  • Date: Wed, 25 Aug 2004 17:57:38 -0700

John,
 
The "SupportVolumeLevel" needs to filter out the
KSPROPERTY_TYPE_BASICSUPPORT requests, and fail other requests.  I noticed
the same problem, which was due to the fact that I did not bounce the
(KSPROPERTY_TYPE_BASICSUPPORT  | KSPROPERTY_TYPE_TOPOLOGY) request.
 
Also (in theory), you should be looking at the "DescriptionSize" to
determine exactly what to return.
 
Harry

-----Original Message-----
From: John D. Farmer [mailto:johndfarmer@xxxxxxxxxxx] 
Sent: Wednesday, August 25, 2004 3:05 PM
To: wdmaudiodev@xxxxxxxxxxxxx
Subject: [wdmaudiodev] Re: AVStream Mixer Problems


DJ,
 
If I have understood the document at:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/stream/hh/s
tream/aud-design_7e776381-911a-4b3a-9bf7-f10f10098dc0.xml.asp
<http://msdn.microsoft.com/library/default.asp?url=/library/en-us/stream/hh/
stream/aud-design_7e776381-911a-4b3a-9bf7-f10f10098dc0.xml.asp>  correctly
I've now changed my Support function to this:
 
// A contiguous memory structure to assign to the data buffer in our
SupportVolumeLevel function.
typedef struct _VOLUME_LEVEL_SUPPORT {
 KSPROPERTY_DESCRIPTION  PropDesc;
 KSPROPERTY_MEMBERSHEADER Members;
 KSPROPERTY_STEPPING_LONG Range;
} VOLUMELEVELSUPPORT, *PVOLUMELEVELSUPPORT;
 
NTSTATUS
SupportVolumeLevel(
 IN  PIRP        irp,
 IN  PKSPROPERTY property,
 OUT PVOID       data
)
{
    DbgPrint("Enter SupportVolumeLevel\n");
    NTSTATUS status;
    
    VOLUMELEVELSUPPORT VolumeSupport;
 
    KSPROPERTY_DESCRIPTION PropDesc;
    
    PropDesc.AccessFlags = KSPROPERTY_TYPE_BASICSUPPORT |
KSPROPERTY_TYPE_GET | KSPROPERTY_TYPE_SET;
    PropDesc.DescriptionSize   = sizeof(KSPROPERTY_DESCRIPTION) +
sizeof(KSPROPERTY_MEMBERSHEADER) + sizeof(KSPROPERTY_STEPPING_LONG);
    PropDesc.PropTypeSet.Set = KSPROPTYPESETID_General;
    PropDesc.PropTypeSet.Id  = VT_I4;
    PropDesc.PropTypeSet.Flags = 0;
    PropDesc.MembersListCount = 1;

    KSPROPERTY_MEMBERSHEADER Members;
 
    Members.MembersFlags = KSPROPERTY_MEMBER_STEPPEDRANGES;
    Members.MembersSize  = sizeof(KSPROPERTY_STEPPING_LONG);
    Members.MembersCount = 1;
    Members.Flags = 0;
 
    KSPROPERTY_STEPPING_LONG Range;
    
    Range.SteppingDelta = 1;
    Range.Bounds.SignedMinimum = -32767; 
    Range.Bounds.SignedMaximum = 32767;
 
    DbgPrint ("BASIC_SUPPORT: max=0x%x min=0x%x step=0x%x\n",
Range.Bounds.SignedMaximum, Range.Bounds.SignedMinimum,
Range.SteppingDelta);
    
    VolumeSupport.PropDesc = PropDesc;
    VolumeSupport.Members = Members;
    VolumeSupport.Range = Range;
    
    *((PVOLUMELEVELSUPPORT) data) = VolumeSupport;
 
    status = STATUS_SUCCESS;
    
    return status;
} // SupportVolumeLevel
 
Some things that are disturbing me are:
    
    - When I go into KS Studio and look at the master volume node the
KSPROPERTY_AUDIO_VOLUMELEVEL is set to GET only even though I clearly
specified Get and Set handlers in my DEFINE_KSPROPERTY_ITEM:
            DEFINE_KSPROPERTY_ITEM
             (
                    KSPROPERTY_AUDIO_VOLUMELEVEL,                //
PropertyId (property item defined in ksmedia.h)
                    PropertyGetVolumeLevel,
// GetPropertyHandler
                    sizeof(KSNODEPROPERTY_AUDIO_CHANNEL),     // MinProperty
(minimum buffer length for property)
                    sizeof(LONG),
// MinData (minimum buffer length for returned data)
                    PropertySetVolumeLevel,
// SetPropertyHandler  
                    NULL,
// Values
                    0,
// RelationsCount
                    NULL,
// Relations
                    SupportVolumeLevel,
// Support Handler
                    0
// SerializedSize
             )
 
    - All the items in the Description for that Property are 0
    
    - If specify NULL instead of a Support Handler I lose the control from
being enabled but I get the SET back
 
Can you guys see anything I'm doing wrong here.  I have searched repeatedly
through the MSDN documentation, but it seems to be very sparse in relation
to this whole topic; especially with regards to AVSTREAM.  In fact most of
the code above is modified from samples in the DDK.
 
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 <mailto: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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