Add a default method for BUS_ADD_CHILD() that just calls

device_add_child_ordered().  Previously, a device driver that wanted to
add a new child device in its identify routine had to know if the parent
driver had a custom bus_add_child method and use BUS_ADD_CHILD() in that
case, otherwise use device_add_child().  Getting it wrong in either
direction would result in panics or failure to add the child device.  Now,
BUS_ADD_CHILD() always works isolating child drivers from having to know
intimate details about the parent driver.

Discussed with:	imp
MFC after:	1 week

1 files changed, 7 insertions, 0 deletions

diff --git a/sys/kern/subr_bus.c b/sys/kern/subr_bus.c
index 3f0a9e2..75b179d 100644
--- a/sys/kern/subr_bus.c
+++ b/sys/kern/subr_bus.c
@@ -2839,6 +2839,13 @@ resource_list_purge(struct resource_list *rl)
 	}
 }
 
+device_t
+bus_generic_add_child(device_t dev, int order, const char *name, int unit)
+{
+
+	return (device_add_child_ordered(dev, order, name, unit));
+}
+
 /**
  * @brief Helper function for implementing DEVICE_PROBE()
  *