# # 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. # # $FreeBSD: src/sys/kern/device_if.m,v 1.7.2.1 2001/07/24 09:49:41 dd Exp $ # $DragonFly: src/sys/kern/device_if.m,v 1.4 2005/10/28 03:25:57 dillon Exp $ # #include INTERFACE device; # # Default implementations of some methods. # CODE { static int null_shutdown(device_t dev) { return 0; } static int null_suspend(device_t dev) { return 0; } static int null_resume(device_t dev) { return 0; } }; # # Probe to see if the device is present. Return 0 if the device exists, # ENXIO if it cannot be found. If some other error happens during the # probe (such as a memory allocation failure), an appropriate error code # should be returned. For cases where more than one driver matches a # device, a priority value can be returned. In this case, success codes # are values less than or equal to zero with the highest value representing # the best match. Failure codes are represented by positive values and # the regular unix error codes should be used for the purpose. # If a driver returns a success code which is less than zero, it must # not assume that it will be the same driver which is attached to the # device. In particular, it must not assume that any values stored in # the softc structure will be available for its attach method and any # resources allocated during probe must be released and re-allocated # if the attach method is called. If a success code of zero is # returned, the driver can assume that it will be the one attached. # # 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; }; # # Called by a parent bus to add new devices to the bus. The driver # should check parent->state to determine whether this is an initial # identification scan on the bus, or whether it is a rescan. If # parent->state == DS_ATTACHED then the identify call is a re-scan. # # Return 0 on success, 0 on rescan, or an error on the initial scan if no # devices were added to the bus. Using generic_bus_identify() will # simply call BUS_ADD_CHILD using the driver name. # # Standard matching devices do not usually have an identify function, whereas # busses or any entity which needs to create static device entries under # the bus will. # STATICMETHOD int identify { driver_t *driver; device_t parent; }; # # 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. # 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; } DEFAULT null_shutdown; # # This is called by the power-management subsystem when a suspend has been # requested by the user or by some automatic mechanism. This gives # drivers a chance to veto the suspend or save their configuration before # power is removed. # METHOD int suspend { device_t dev; } DEFAULT null_suspend; METHOD int resume { device_t dev; } DEFAULT null_resume;