Re: Starting a driver within a driver...

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Device #2 depends on Device #1.

Can I do something with dependencies to ensure the OS starts device #1
first, then device #2?

There is no system provided way to control start order of two devices.


Assuming that cannot be done with dependencies, I
need #1 to signal #2 to start--and #2 to start only if #1 is already
started. Then the order in which the OS tells the drivers to start won't
matter--while the dependency effectively holds.


You can devise your own signalling technique. I have used callback objects
(ExCreateCallback) in my drivers to control load order dependencies of two
independent drivers. If you need sample code, send me an email note.

The way I see you solving the problem is that if #2 is started before #1
then #2 would complete the start-irp with STATUS_SUCCESS, but wouldn't
really initialize the device until #1 starts and signals #2. Correct? I'm
not sure all the thing that PCI bus driver does when it receives the
start-irp, but wouldn't you have any problem if start-device of #2 is
handled by the pci bus before #1?


.

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