Drew Hoffman

I should build out a DeviceIOControl interface so I can send codec verbs and dump the codec state from a user-mode program and don't need to rely on the kernel debugger. Will get to that when I have time. It's busy around the holidays. Also, HDMI Display Audio is unfortunately not likely to work at this time as it seems to expose a codec with only a SPDIF output and the current codec parser is only looking for analog output pins.

WDM Sound Blaster digital and MIDI emulation should work but occasionally the sound will drop out for a while if there are a few seconds when nothing is playing. I think there is a race condition bug with quickly stopping and starting the stream. The WaveCyclic port driver aggressively sets the state to Stop whenever there is nothing playing but it can be held open by having Winamp or similar open in the background and paused. The Mute check box is disabled because it was disabled in the original SB16 sample driver and I haven't changed the topology miniport much. (I also need to remove the EQ settings it has since they don't do anything but I don't think those are exposed in the volume control panel, there was originally an example cpl addon for that. )

Nvidia and ULI chipsets would be the highest priority to test as I don't have any of those myself and they need some PCI Configuration Space fixes that I blindly copied from VSBHDA. Tests on as many combinations of controller and codec as possible would be appreciated. I already know there's no sound on on IDT / Sigmatel codecs yet and will continue to debug that. The driver should function without DirectX 8, at least it does in Virtualbox, with maybe the only issue being choppier MIDI playback. I'm ignoring the requested interrupt interval from ks.sys (which is always 10ms) because Virtualbox seems to require a power of 2 audio buffer size not just a multiple of 128 bytes. Haven't tested on 98FE or 95 with the USB support added yet. DirectX 8.1 updates these audio related files: Ks.sys, Stream.sys, mskssrv.sys There's also a Microsoft WDM Audio Update hotfix KB242937 which updates kmixer.sys, portcls.sys, usbaudio.sys, wdmaud.sys I do have a QIYIDA X99 motherboard I can try to test on myself, if I can figure out Omores's trick for running 98 from a USB key in legacy emulation mode.

Dangit. Good catch. I'll rework all of that and get another release up tonight. Edit: Fixed stupid interrupt eating bug and other problems with the Interrupt Service Routine. https://github.com/andrew-hoffman/WDMHDA/releases/tag/Alpha-011

In the ISR I am first reading the INTSTS register and returning False if it is 0 (or 0xFFFFFFFF which happens on controller shutdown sometimes ). As far as I can tell this is correct, but on the Wyse Rx0 thin client with AMD SB600 having my driver loaded slows the system down immensely and causes the USB ports to stop working suggesting that there might be an IRQ storm issue. If the driver will initialize and load and media players attempt to play sound but nothing is heard, please try all audio jacks. The codec node parser is also fairly rudimentary at the moment and I'm not going to guarantee it works with every codec or even most of them. I've had very little success getting Windows 98 installed and working on systems as new as that anyway though clearly some of the people here are able to manage it.

Huh. Are you able to get kernel debug prints on that system by any methods? Try the version in the hdac\buildchk folder in the download. Does it hang on installation or just on the first reboot? If it lets you install and then hangs on restarting you might be able to get some debug output with DbgView, otherwise you really have to have a hardware serial port and the newest laptops I know with that are on Dell Latitude E series which have one on some docking stations. One possible issue is that the driver is not currently designed to be able to load for multiple devices and the PCH on that laptop will have HDMI display audio as well as the HDA bus. There might also be issues with IRQ sharing with the USB controller but if that's the case I'm not sure how to fix the problems. I know you are experienced with Windows Driver development so maybe you would have some suggestions.

https://github.com/andrew-hoffman/WDMHDA This audio driver now functions well in VMWare and VirtualBox, and may work on some real hardware with an Intel controller and Realtek audio codec. More testing and work is still needed. Any compatibility reports would be appreciated.