From 74014b7f0acd542fb53e64bc8cfb8f5ce3d48499 Mon Sep 17 00:00:00 2001 From: Warner Losh Date: Wed, 11 Sep 2002 04:22:10 +0000 Subject: [PATCH] Clarify the return value from child_present. --- sys/kern/bus_if.m | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/sys/kern/bus_if.m b/sys/kern/bus_if.m index c5350beaf9c..7b8a13501e9 100644 --- a/sys/kern/bus_if.m +++ b/sys/kern/bus_if.m @@ -247,6 +247,13 @@ METHOD struct resource_list * get_resource_list { # # Is the hardware described by _child still attached to the system? # +# This method should return 0 if the device is not present. It should +# return -1 if it is present. Any errors in determining should be +# returned as a normal errno value. Client drivers are to assume that +# the device is present, even if there is an error determining if it is +# there. Busses are to try to avoid returning errors, but newcard will return +# an error if the device fails to implement this method. +# METHOD int child_present { device_t _dev; device_t _child;