dprado@xxxxxxxxxxxxxx wrote:
Well, it is clear to me that this is a lot harder than I previously thought. I
still have a "basic" question regarding the stacking of drivers. All the
information I have seen on WDM filter drivers, state that filter drivers sit
above or below a function driver and "transparently" filter IRPs . I installed
a simple "passtrough" driver as an UpperFilter driver to the MSVAD virtual
audio device from the DDK and it worked as expected, logging the IRPs with
KdPrint. After that I modified the INF file in order to install the passthrough
filter driver as a function driver, including registering wave interfaces for
this driver. I manually configured the MSVAD virtual audio driver as a
LowerFilter of this Passthrough filter driver ( that was actually installed as
a function driver ). This worked, but I am not sure if this is somthing that I
shouldn´t have done.
Generally, If I have a filter driver "XYZ" as an UpperFilter to a function
driver "ABC" , can I install "XYZ" as a function driver and have the "ABC"
driver as a lowerfilter to XYZ? Would it have the same effect?
This same setup did not work when using USBaudio as a LowerFilter to the passthough driver The passthough driver refused to load.
-- - Tim Roberts, timr@xxxxxxxxx Providenza & Boekelheide, Inc.
******************
WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx
URL to WDMAUDIODEV page: http://www.wdmaudiodev.de/