Allow device hints to wire the unit numbers of devices.

- An "at" hint now reserves a device name.
- A new BUS_HINT_DEVICE_UNIT method is added to the bus interface.  When
  determining the unit number of a device, this method is invoked to
  let the bus driver specify the unit of a device given a specific
  devclass.  This is the only way a device can be given a name reserved
  via an "at" hint.
- Implement BUS_HINT_DEVICE_UNIT() for the acpi(4) and isa(4) bus drivers.
  Both of these busses implement this by comparing the resources for a
  given hint device with the resources enumerated by ACPI/PnPBIOS and
  wire a unit if the hint resources are a subset of the "real" resources.
- Use bus_hinted_children() for adding hinted devices on isa(4) busses
  now instead of doing it by hand.
- Remove the unit kludging from sio(4) as it is no longer necessary.

Prodding from:	peter, imp
OK'd by:	marcel
MFC after:	1 month

1 files changed, 1 insertions, 0 deletions

diff --git a/sys/isa/isa_common.h b/sys/isa/isa_common.h
index c6d6e43..340ad17 100644
--- a/sys/isa/isa_common.h
+++ b/sys/isa/isa_common.h
@@ -59,6 +59,7 @@ struct isa_device {
 	int			id_pnpbios_handle; /* pnp handle, if any */
 	int			id_pnp_csn; /* pnp Card Number */
 	int			id_pnp_ldn; /* pnp Logical device on card */
+	int			id_order;
 };
 
 #define DEVTOISA(dev)	((struct isa_device *) device_get_ivars(dev))