Re: bus_generic_probe() is wrong I think

[John Baldwin <jhb@xxxxxxxxxxx>]

On 31-Aug-2002 M. Warner Losh wrote:
> In message: <XFMail.20020830133542.jhb@xxxxxxxxxxx>
>             John Baldwin <jhb@xxxxxxxxxxx> writes:
>: If we are going to support having multiple driver's for a given device
>: which is a bus (like we do now for PCI busses and like I am doing for
>: this concept of a system buson i386) then I think that bus devices do
>: not need to go identify child devices until after they have won the
>: probe and are being attached.  Thus, I'm ending up calling
>: bus_generic_probe() in my attach routines instead of my probe routines.
>: Does this make sense or am I missing something?  I at least have to do
>: this in the system bus case here for the same reasons that when I added
>: another PCI bus driver, I had to change the PCI drivers to add children
>: devices (equivalent of doing an identify) during attach() time and not
>: during probe() time.
> 
> A more fundamental question is why bus_generic_probe() does the child
> attach/probe?  In the probe routine, there's no guarantee that the
> bus will actually attach at some later point.  Shouldn't that be in a
> bus_generic_attach() routine?  The probe should just say 'is this bus
> here' and the attach should make it possible to then probe the
> children after a successful attach.

Pretty much what I was saying.  I have an atsys(4) driver btw that apm
and nexus_pcib are now descendants of and only gets attached if the
acpi identify fails in the jhb_acpipci p4 branch.

-- 

John Baldwin <jhb@xxxxxxxxxxx>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve!"  -  http://www.FreeBSD.org/

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