Document all the BUS_PROBE_* values.

Note to the mdoc gods: This may need some teaks.
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imp 2008-03-09 05:31:31 +00:00
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@ -28,7 +28,7 @@
.\"
.\" $FreeBSD$
.\"
.Dd January 6, 2005
.Dd March 3, 2008
.Dt DEVICE_PROBE 9
.Os
.Sh NAME
@ -83,6 +83,50 @@ For values equal to or less than
zero: zero indicates highest priority, no further probing is done;
for a value less than zero, the lower the value the lower the
priority, e.g.\& -100 indicates a lower priority than -50.
.Pp
The following values are used by convention to indicate different
strengths of matching in a probe routine.
Except as noted, these are just suggested values, and there's nothing
magical about them.
.Bl -tag -width BUS_PROBE_NOWILDCARD
.It BUS_PROBE_SPECIFIC
The device that cannot be reprobed, and that no
possible other driver may exist (typically legacy drivers who don't fallow
all the rules, or special needs drivers).
.It BUS_PROBE_VENDOR
The device is supported by a vendor driver.
This is for source or binary drivers that are not yet integrated into the
.Fx
tree.
Its use in the base OS is prohibited.
.It BUS_PROBE_DEFAULT
The device is a normal device matching some plug and play ID. This is
the normal return value for drivers to use.
It is intended that nearly all of the drivers in the tree should return
this value.
.It BUS_PROBE_LOW_PRIORITY
The driver is a legacy driver, or an otherwise less desirable driver
for a given plug and play ID.
The driver has special requirements like when there are two drivers
that support overlapping series of hardware devices.
In this case the one that supports the older part of the line would
return this value, while the one that supports the newer ones would
return BUS_PROBE_DEFAULT.
.It BUS_PROBE_GENERIC
The driver matches the type of device generally.
This allows drivers to match all serial ports generally, with sepcialized
drivers matching particular types of serial ports that need special
treatment for some reason.
.It BUS_PROBE_HOOVER
The driver matches all unclaimed devices on a bus.
The
.Xr ugen 5
device is one example.
.It BUS_PROBE_NOWILDCARD
The driver expects its parent to tell it which children to manage
and no probing is really done.
The device only matches if its parent bus specifically said to use
this driver.
.Sh SEE ALSO
.Xr device 9 ,
.Xr DEVICE_ATTACH 9 ,