[Add missing files from previous commit]

Major changes to the generic device framework for FreeBSD/alpha:

* Eliminate bus_t and make it possible for all devices to have
  attached children.

* Support dynamically extendable interfaces for drivers to replace
  both the function pointers in driver_t and bus_ops_t (which has been
  removed entirely.  Two system defined interfaces have been defined,
  'device' which is mandatory for all devices and 'bus' which is
  recommended for all devices which support attached children.

* In addition, the alpha port defines two simple interfaces 'clock'
  for attaching various real time clocks to the system and 'mcclock'
  for the many different variations of mc146818 clocks which can be
  attached to different alpha platforms.  This eliminates two more
  function pointer tables in favour of the generic method dispatch
  system provided by the device framework.

Future device interfaces may include:

* cdev and bdev interfaces for devfs to use in replacement for specfs
  and the fixed interfaces bdevsw and cdevsw.

* scsi interface to replace struct scsi_adapter (not sure how this
  works in CAM but I imagine there is something similar there).

* various tailored interfaces for different bus types such as pci,
  isa, pccard etc.

1 files changed, 69 insertions, 0 deletions

diff --git a/sys/kern/device_if.m b/sys/kern/device_if.m
new file mode 100644
index 000000000000..4ae1df86a0db
--- /dev/null
+++ b/sys/kern/device_if.m
@@ -0,0 +1,69 @@
+#
+# Copyright (c) 1998 Doug Rabson
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+#	$Id$
+#
+
+INTERFACE device
+
+#
+# Probe to see if the device is present.  Return 0 if the device exists,
+# ENXIO if it cannot be found.
+# 
+# Devices which implement busses should use this method to probe for
+# the existence of devices attached to the bus and add them as
+# children.  If this is combined with the use of bus_generic_attach,
+# the child devices will be automatically probed and attached.
+#
+METHOD int probe {
+	device_t dev;
+};
+
+#
+# Attach a device to the system.  The probe method will have been
+# called and will have indicated that the device exists.  This routine
+# should initialise the hardware and allocate other system resources
+# (such as devfs entries).  Returns 0 on success.
+#
+METHOD int attach {
+	device_t dev;
+};
+
+#
+# Detach a device.  This can be called if the user is replacing the
+# driver software or if a device is about to be physically removed
+# from the system (e.g. for pccard devices).  Returns 0 on success.
+#
+METHOD int detach {
+	device_t dev;
+};
+
+#
+# This is called during system shutdown to allow the driver to put the 
+# hardware into a consistent state for rebooting the computer.
+#
+METHOD int shutdown {
+	device_t dev;
+};