xref: /freebsd/sys/kern/bus_if.m (revision 3332f1b444d4a73238e9f59cca27bfc95fe936bd)
1#-
2# Copyright (c) 1998-2004 Doug Rabson
3# All rights reserved.
4#
5# Redistribution and use in source and binary forms, with or without
6# modification, are permitted provided that the following conditions
7# are met:
8# 1. Redistributions of source code must retain the above copyright
9#    notice, this list of conditions and the following disclaimer.
10# 2. Redistributions in binary form must reproduce the above copyright
11#    notice, this list of conditions and the following disclaimer in the
12#    documentation and/or other materials provided with the distribution.
13#
14# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24# SUCH DAMAGE.
25#
26# $FreeBSD$
27#
28
29#include <sys/types.h>
30#include <sys/systm.h>
31#include <sys/bus.h>
32
33/**
34 * @defgroup BUS bus - KObj methods for drivers of devices with children
35 * @brief A set of methods required device drivers that support
36 * child devices.
37 * @{
38 */
39INTERFACE bus;
40
41#
42# Default implementations of some methods.
43#
44CODE {
45	static struct resource *
46	null_alloc_resource(device_t dev, device_t child,
47	    int type, int *rid, rman_res_t start, rman_res_t end,
48	    rman_res_t count, u_int flags)
49	{
50	    return (0);
51	}
52
53	static int
54	null_remap_intr(device_t bus, device_t dev, u_int irq)
55	{
56
57		if (dev != NULL)
58			return (BUS_REMAP_INTR(dev, NULL, irq));
59		return (ENXIO);
60	}
61
62	static device_t
63	null_add_child(device_t bus, int order, const char *name,
64	    int unit)
65	{
66
67		panic("bus_add_child is not implemented");
68	}
69
70	static int null_reset_post(device_t bus, device_t dev)
71	{
72		return (0);
73	}
74
75	static int null_reset_prepare(device_t bus, device_t dev)
76	{
77		return (0);
78	}
79
80	static int
81	null_translate_resource(device_t bus, int type, rman_res_t start,
82		rman_res_t *newstart)
83	{
84		if (device_get_parent(bus) != NULL)
85			return (BUS_TRANSLATE_RESOURCE(device_get_parent(bus),
86			    type, start, newstart));
87
88		*newstart = start;
89		return (0);
90	}
91
92	static ssize_t
93	null_get_property(device_t dev, device_t child, const char *propname,
94	    void *propvalue, size_t size)
95	{
96		return (-1);
97	}
98};
99
100/**
101 * @brief Print a description of a child device
102 *
103 * This is called from system code which prints out a description of a
104 * device. It should describe the attachment that the child has with
105 * the parent. For instance the TurboLaser bus prints which node the
106 * device is attached to. See bus_generic_print_child() for more
107 * information.
108 *
109 * @param _dev		the device whose child is being printed
110 * @param _child	the child device to describe
111 *
112 * @returns		the number of characters output.
113 */
114METHOD int print_child {
115	device_t _dev;
116	device_t _child;
117} DEFAULT bus_generic_print_child;
118
119/**
120 * @brief Print a notification about an unprobed child device.
121 *
122 * Called for each child device that did not succeed in probing for a
123 * driver.
124 *
125 * @param _dev		the device whose child was being probed
126 * @param _child	the child device which failed to probe
127 */
128METHOD void probe_nomatch {
129        device_t _dev;
130        device_t _child;
131};
132
133/**
134 * @brief Read the value of a bus-specific attribute of a device
135 *
136 * This method, along with BUS_WRITE_IVAR() manages a bus-specific set
137 * of instance variables of a child device.  The intention is that
138 * each different type of bus defines a set of appropriate instance
139 * variables (such as ports and irqs for ISA bus etc.)
140 *
141 * This information could be given to the child device as a struct but
142 * that makes it hard for a bus to add or remove variables without
143 * forcing an edit and recompile for all drivers which may not be
144 * possible for vendor supplied binary drivers.
145 *
146 * This method copies the value of an instance variable to the
147 * location specified by @p *_result.
148 *
149 * @param _dev		the device whose child was being examined
150 * @param _child	the child device whose instance variable is
151 *			being read
152 * @param _index	the instance variable to read
153 * @param _result	a location to receive the instance variable
154 *			value
155 *
156 * @retval 0		success
157 * @retval ENOENT	no such instance variable is supported by @p
158 *			_dev
159 */
160METHOD int read_ivar {
161	device_t _dev;
162	device_t _child;
163	int _index;
164	uintptr_t *_result;
165};
166
167/**
168 * @brief Write the value of a bus-specific attribute of a device
169 *
170 * This method sets the value of an instance variable to @p _value.
171 *
172 * @param _dev		the device whose child was being updated
173 * @param _child	the child device whose instance variable is
174 *			being written
175 * @param _index	the instance variable to write
176 * @param _value	the value to write to that instance variable
177 *
178 * @retval 0		success
179 * @retval ENOENT	no such instance variable is supported by @p
180 *			_dev
181 * @retval EINVAL	the instance variable was recognised but
182 *			contains a read-only value
183 */
184METHOD int write_ivar {
185	device_t _dev;
186	device_t _child;
187	int _indx;
188	uintptr_t _value;
189};
190
191/**
192 * @brief Notify a bus that a child was deleted
193 *
194 * Called at the beginning of device_delete_child() to allow the parent
195 * to teardown any bus-specific state for the child.
196 *
197 * @param _dev		the device whose child is being deleted
198 * @param _child	the child device which is being deleted
199 */
200METHOD void child_deleted {
201	device_t _dev;
202	device_t _child;
203};
204
205/**
206 * @brief Notify a bus that a child was detached
207 *
208 * Called after the child's DEVICE_DETACH() method to allow the parent
209 * to reclaim any resources allocated on behalf of the child.
210 *
211 * @param _dev		the device whose child changed state
212 * @param _child	the child device which changed state
213 */
214METHOD void child_detached {
215	device_t _dev;
216	device_t _child;
217};
218
219/**
220 * @brief Notify a bus that a new driver was added
221 *
222 * Called when a new driver is added to the devclass which owns this
223 * bus. The generic implementation of this method attempts to probe and
224 * attach any un-matched children of the bus.
225 *
226 * @param _dev		the device whose devclass had a new driver
227 *			added to it
228 * @param _driver	the new driver which was added
229 */
230METHOD void driver_added {
231	device_t _dev;
232	driver_t *_driver;
233} DEFAULT bus_generic_driver_added;
234
235/**
236 * @brief Create a new child device
237 *
238 * For buses which use use drivers supporting DEVICE_IDENTIFY() to
239 * enumerate their devices, this method is used to create new
240 * device instances. The new device will be added after the last
241 * existing child with the same order. Implementations of bus_add_child
242 * call device_add_child_ordered to add the child and often add
243 * a suitable ivar to the device specific to that bus.
244 *
245 * @param _dev		the bus device which will be the parent of the
246 *			new child device
247 * @param _order	a value which is used to partially sort the
248 *			children of @p _dev - devices created using
249 *			lower values of @p _order appear first in @p
250 *			_dev's list of children
251 * @param _name		devclass name for new device or @c NULL if not
252 *			specified
253 * @param _unit		unit number for new device or @c -1 if not
254 *			specified
255 */
256METHOD device_t add_child {
257	device_t _dev;
258	u_int _order;
259	const char *_name;
260	int _unit;
261} DEFAULT null_add_child;
262
263/**
264 * @brief Rescan the bus
265 *
266 * This method is called by a parent bridge or devctl to trigger a bus
267 * rescan.  The rescan should delete devices no longer present and
268 * enumerate devices that have newly arrived.
269 *
270 * @param _dev		the bus device
271 */
272METHOD int rescan {
273	device_t _dev;
274}
275
276/**
277 * @brief Allocate a system resource
278 *
279 * This method is called by child devices of a bus to allocate resources.
280 * The types are defined in <machine/resource.h>; the meaning of the
281 * resource-ID field varies from bus to bus (but @p *rid == 0 is always
282 * valid if the resource type is). If a resource was allocated and the
283 * caller did not use the RF_ACTIVE to specify that it should be
284 * activated immediately, the caller is responsible for calling
285 * BUS_ACTIVATE_RESOURCE() when it actually uses the resource.
286 *
287 * @param _dev		the parent device of @p _child
288 * @param _child	the device which is requesting an allocation
289 * @param _type		the type of resource to allocate
290 * @param _rid		a pointer to the resource identifier
291 * @param _start	hint at the start of the resource range - pass
292 *			@c 0 for any start address
293 * @param _end		hint at the end of the resource range - pass
294 *			@c ~0 for any end address
295 * @param _count	hint at the size of range required - pass @c 1
296 *			for any size
297 * @param _flags	any extra flags to control the resource
298 *			allocation - see @c RF_XXX flags in
299 *			<sys/rman.h> for details
300 *
301 * @returns		the resource which was allocated or @c NULL if no
302 *			resource could be allocated
303 */
304METHOD struct resource * alloc_resource {
305	device_t	_dev;
306	device_t	_child;
307	int		_type;
308	int	       *_rid;
309	rman_res_t	_start;
310	rman_res_t	_end;
311	rman_res_t	_count;
312	u_int		_flags;
313} DEFAULT null_alloc_resource;
314
315/**
316 * @brief Activate a resource
317 *
318 * Activate a resource previously allocated with
319 * BUS_ALLOC_RESOURCE().  This may enable decoding of this resource in a
320 * device for instance.  It will also establish a mapping for the resource
321 * unless RF_UNMAPPED was set when allocating the resource.
322 *
323 * @param _dev		the parent device of @p _child
324 * @param _child	the device which allocated the resource
325 * @param _type		the type of resource
326 * @param _rid		the resource identifier
327 * @param _r		the resource to activate
328 */
329METHOD int activate_resource {
330	device_t	_dev;
331	device_t	_child;
332	int		_type;
333	int		_rid;
334	struct resource *_r;
335};
336
337
338/**
339 * @brief Map a resource
340 *
341 * Allocate a mapping for a range of an active resource.  The mapping
342 * is described by a struct resource_map object.  This may for instance
343 * map a memory region into the kernel's virtual address space.
344 *
345 * @param _dev		the parent device of @p _child
346 * @param _child	the device which allocated the resource
347 * @param _type		the type of resource
348 * @param _r		the resource to map
349 * @param _args		optional attributes of the mapping
350 * @param _map		the mapping
351 */
352METHOD int map_resource {
353	device_t	_dev;
354	device_t	_child;
355	int		_type;
356	struct resource *_r;
357	struct resource_map_request *_args;
358	struct resource_map *_map;
359} DEFAULT bus_generic_map_resource;
360
361
362/**
363 * @brief Unmap a resource
364 *
365 * Release a mapping previously allocated with
366 * BUS_MAP_RESOURCE(). This may for instance unmap a memory region
367 * from the kernel's virtual address space.
368 *
369 * @param _dev		the parent device of @p _child
370 * @param _child	the device which allocated the resource
371 * @param _type		the type of resource
372 * @param _r		the resource
373 * @param _map		the mapping to release
374 */
375METHOD int unmap_resource {
376	device_t	_dev;
377	device_t	_child;
378	int		_type;
379	struct resource *_r;
380	struct resource_map *_map;
381} DEFAULT bus_generic_unmap_resource;
382
383
384/**
385 * @brief Deactivate a resource
386 *
387 * Deactivate a resource previously allocated with
388 * BUS_ALLOC_RESOURCE().
389 *
390 * @param _dev		the parent device of @p _child
391 * @param _child	the device which allocated the resource
392 * @param _type		the type of resource
393 * @param _rid		the resource identifier
394 * @param _r		the resource to deactivate
395 */
396METHOD int deactivate_resource {
397	device_t	_dev;
398	device_t	_child;
399	int		_type;
400	int		_rid;
401	struct resource *_r;
402};
403
404/**
405 * @brief Adjust a resource
406 *
407 * Adjust the start and/or end of a resource allocated by
408 * BUS_ALLOC_RESOURCE.  At least part of the new address range must overlap
409 * with the existing address range.  If the successful, the resource's range
410 * will be adjusted to [start, end] on return.
411 *
412 * @param _dev		the parent device of @p _child
413 * @param _child	the device which allocated the resource
414 * @param _type		the type of resource
415 * @param _res		the resource to adjust
416 * @param _start	the new starting address of the resource range
417 * @param _end		the new ending address of the resource range
418 */
419METHOD int adjust_resource {
420	device_t	_dev;
421	device_t	_child;
422	int		_type;
423	struct resource *_res;
424	rman_res_t	_start;
425	rman_res_t	_end;
426};
427
428
429/**
430 * @brief translate a resource value
431 *
432 *
433 * @param _dev		the device associated with the resource
434 * @param _type		the type of resource
435 * @param _start	the starting address of the resource range
436 * @param _newstart	the new starting address of the resource range
437 */
438METHOD int translate_resource {
439	device_t	_dev;
440	int		_type;
441	rman_res_t	_start;
442	rman_res_t	*_newstart;
443} DEFAULT null_translate_resource;
444
445/**
446 * @brief Release a resource
447 *
448 * Free a resource allocated by the BUS_ALLOC_RESOURCE.  The @p _rid
449 * value must be the same as the one returned by BUS_ALLOC_RESOURCE()
450 * (which is not necessarily the same as the one the client passed).
451 *
452 * @param _dev		the parent device of @p _child
453 * @param _child	the device which allocated the resource
454 * @param _type		the type of resource
455 * @param _rid		the resource identifier
456 * @param _r		the resource to release
457 */
458METHOD int release_resource {
459	device_t	_dev;
460	device_t	_child;
461	int		_type;
462	int		_rid;
463	struct resource *_res;
464};
465
466/**
467 * @brief Install an interrupt handler
468 *
469 * This method is used to associate an interrupt handler function with
470 * an irq resource. When the interrupt triggers, the function @p _intr
471 * will be called with the value of @p _arg as its single
472 * argument. The value returned in @p *_cookiep is used to cancel the
473 * interrupt handler - the caller should save this value to use in a
474 * future call to BUS_TEARDOWN_INTR().
475 *
476 * @param _dev		the parent device of @p _child
477 * @param _child	the device which allocated the resource
478 * @param _irq		the resource representing the interrupt
479 * @param _flags	a set of bits from enum intr_type specifying
480 *			the class of interrupt
481 * @param _intr		the function to call when the interrupt
482 *			triggers
483 * @param _arg		a value to use as the single argument in calls
484 *			to @p _intr
485 * @param _cookiep	a pointer to a location to receive a cookie
486 *			value that may be used to remove the interrupt
487 *			handler
488 */
489METHOD int setup_intr {
490	device_t	_dev;
491	device_t	_child;
492	struct resource *_irq;
493	int		_flags;
494	driver_filter_t	*_filter;
495	driver_intr_t	*_intr;
496	void		*_arg;
497	void		**_cookiep;
498};
499
500/**
501 * @brief Uninstall an interrupt handler
502 *
503 * This method is used to disassociate an interrupt handler function
504 * with an irq resource. The value of @p _cookie must be the value
505 * returned from a previous call to BUS_SETUP_INTR().
506 *
507 * @param _dev		the parent device of @p _child
508 * @param _child	the device which allocated the resource
509 * @param _irq		the resource representing the interrupt
510 * @param _cookie	the cookie value returned when the interrupt
511 *			was originally registered
512 */
513METHOD int teardown_intr {
514	device_t	_dev;
515	device_t	_child;
516	struct resource	*_irq;
517	void		*_cookie;
518};
519
520/**
521 * @brief Suspend an interrupt handler
522 *
523 * This method is used to mark a handler as suspended in the case
524 * that the associated device is powered down and cannot be a source
525 * for the, typically shared, interrupt.
526 * The value of @p _irq must be the interrupt resource passed
527 * to a previous call to BUS_SETUP_INTR().
528 *
529 * @param _dev		the parent device of @p _child
530 * @param _child	the device which allocated the resource
531 * @param _irq		the resource representing the interrupt
532 */
533METHOD int suspend_intr {
534	device_t	_dev;
535	device_t	_child;
536	struct resource *_irq;
537} DEFAULT bus_generic_suspend_intr;
538
539/**
540 * @brief Resume an interrupt handler
541 *
542 * This method is used to clear suspended state of a handler when
543 * the associated device is powered up and can be an interrupt source
544 * again.
545 * The value of @p _irq must be the interrupt resource passed
546 * to a previous call to BUS_SETUP_INTR().
547 *
548 * @param _dev		the parent device of @p _child
549 * @param _child	the device which allocated the resource
550 * @param _irq		the resource representing the interrupt
551 */
552METHOD int resume_intr {
553	device_t	_dev;
554	device_t	_child;
555	struct resource *_irq;
556} DEFAULT bus_generic_resume_intr;
557
558/**
559 * @brief Define a resource which can be allocated with
560 * BUS_ALLOC_RESOURCE().
561 *
562 * This method is used by some buses (typically ISA) to allow a
563 * driver to describe a resource range that it would like to
564 * allocate. The resource defined by @p _type and @p _rid is defined
565 * to start at @p _start and to include @p _count indices in its
566 * range.
567 *
568 * @param _dev		the parent device of @p _child
569 * @param _child	the device which owns the resource
570 * @param _type		the type of resource
571 * @param _rid		the resource identifier
572 * @param _start	the start of the resource range
573 * @param _count	the size of the resource range
574 */
575METHOD int set_resource {
576	device_t	_dev;
577	device_t	_child;
578	int		_type;
579	int		_rid;
580	rman_res_t	_start;
581	rman_res_t	_count;
582};
583
584/**
585 * @brief Describe a resource
586 *
587 * This method allows a driver to examine the range used for a given
588 * resource without actually allocating it.
589 *
590 * @param _dev		the parent device of @p _child
591 * @param _child	the device which owns the resource
592 * @param _type		the type of resource
593 * @param _rid		the resource identifier
594 * @param _start	the address of a location to receive the start
595 *			index of the resource range
596 * @param _count	the address of a location to receive the size
597 *			of the resource range
598 */
599METHOD int get_resource {
600	device_t	_dev;
601	device_t	_child;
602	int		_type;
603	int		_rid;
604	rman_res_t	*_startp;
605	rman_res_t	*_countp;
606};
607
608/**
609 * @brief Delete a resource.
610 *
611 * Use this to delete a resource (possibly one previously added with
612 * BUS_SET_RESOURCE()).
613 *
614 * @param _dev		the parent device of @p _child
615 * @param _child	the device which owns the resource
616 * @param _type		the type of resource
617 * @param _rid		the resource identifier
618 */
619METHOD void delete_resource {
620	device_t	_dev;
621	device_t	_child;
622	int		_type;
623	int		_rid;
624};
625
626/**
627 * @brief Return a struct resource_list.
628 *
629 * Used by drivers which use bus_generic_rl_alloc_resource() etc. to
630 * implement their resource handling. It should return the resource
631 * list of the given child device.
632 *
633 * @param _dev		the parent device of @p _child
634 * @param _child	the device which owns the resource list
635 */
636METHOD struct resource_list * get_resource_list {
637	device_t	_dev;
638	device_t	_child;
639} DEFAULT bus_generic_get_resource_list;
640
641/**
642 * @brief Is the hardware described by @p _child still attached to the
643 * system?
644 *
645 * This method should return 0 if the device is not present.  It
646 * should return -1 if it is present.  Any errors in determining
647 * should be returned as a normal errno value.  Client drivers are to
648 * assume that the device is present, even if there is an error
649 * determining if it is there.  Buses are to try to avoid returning
650 * errors, but newcard will return an error if the device fails to
651 * implement this method.
652 *
653 * @param _dev		the parent device of @p _child
654 * @param _child	the device which is being examined
655 */
656METHOD int child_present {
657	device_t	_dev;
658	device_t	_child;
659} DEFAULT bus_generic_child_present;
660
661/**
662 * @brief Returns the pnp info for this device.
663 *
664 * Return it as a string, appended to @p _sb
665 *
666 * The string must be formatted as a space-separated list of
667 * name=value pairs.  Names may only contain alphanumeric characters,
668 * underscores ('_') and hyphens ('-').  Values can contain any
669 * non-whitespace characters.  Values containing whitespace can be
670 * quoted with double quotes ('"').  Double quotes and backslashes in
671 * quoted values can be escaped with backslashes ('\').
672 *
673 * @param _dev		the parent device of @p _child
674 * @param _child	the device which is being examined
675 * @param _sb		sbuf for results string
676 */
677METHOD int child_pnpinfo {
678	device_t	_dev;
679	device_t	_child;
680	struct sbuf	*_sb;
681} DEFAULT bus_generic_child_pnpinfo;
682
683/**
684 * @brief Returns the location for this device.
685 *
686 * Return it as a string, appended to @p _sb
687 *
688 * The string must be formatted as a space-separated list of
689 * name=value pairs.  Names may only contain alphanumeric characters,
690 * underscores ('_') and hyphens ('-').  Values can contain any
691 * non-whitespace characters.  Values containing whitespace can be
692 * quoted with double quotes ('"').  Double quotes and backslashes in
693 * quoted values can be escaped with backslashes ('\').
694 *
695 * @param _dev		the parent device of @p _child
696 * @param _child	the device which is being examined
697 * @param _sb		sbuf for results string
698 */
699METHOD int child_location {
700	device_t	_dev;
701	device_t	_child;
702	struct sbuf	*_sb;
703} DEFAULT bus_generic_child_location;
704
705/**
706 * @brief Allow drivers to request that an interrupt be bound to a specific
707 * CPU.
708 *
709 * @param _dev		the parent device of @p _child
710 * @param _child	the device which allocated the resource
711 * @param _irq		the resource representing the interrupt
712 * @param _cpu		the CPU to bind the interrupt to
713 */
714METHOD int bind_intr {
715	device_t	_dev;
716	device_t	_child;
717	struct resource *_irq;
718	int		_cpu;
719} DEFAULT bus_generic_bind_intr;
720
721/**
722 * @brief Allow (bus) drivers to specify the trigger mode and polarity
723 * of the specified interrupt.
724 *
725 * @param _dev		the bus device
726 * @param _irq		the interrupt number to modify
727 * @param _trig		the trigger mode required
728 * @param _pol		the interrupt polarity required
729 */
730METHOD int config_intr {
731	device_t	_dev;
732	int		_irq;
733	enum intr_trigger _trig;
734	enum intr_polarity _pol;
735} DEFAULT bus_generic_config_intr;
736
737/**
738 * @brief Allow drivers to associate a description with an active
739 * interrupt handler.
740 *
741 * @param _dev		the parent device of @p _child
742 * @param _child	the device which allocated the resource
743 * @param _irq		the resource representing the interrupt
744 * @param _cookie	the cookie value returned when the interrupt
745 *			was originally registered
746 * @param _descr	the description to associate with the interrupt
747 */
748METHOD int describe_intr {
749	device_t	_dev;
750	device_t	_child;
751	struct resource *_irq;
752	void		*_cookie;
753	const char	*_descr;
754} DEFAULT bus_generic_describe_intr;
755
756/**
757 * @brief Notify a (bus) driver about a child that the hints mechanism
758 * believes it has discovered.
759 *
760 * The bus is responsible for then adding the child in the right order
761 * and discovering other things about the child.  The bus driver is
762 * free to ignore this hint, to do special things, etc.  It is all up
763 * to the bus driver to interpret.
764 *
765 * This method is only called in response to the parent bus asking for
766 * hinted devices to be enumerated.
767 *
768 * @param _dev		the bus device
769 * @param _dname	the name of the device w/o unit numbers
770 * @param _dunit	the unit number of the device
771 */
772METHOD void hinted_child {
773	device_t	_dev;
774	const char	*_dname;
775	int		_dunit;
776};
777
778/**
779 * @brief Returns bus_dma_tag_t for use w/ devices on the bus.
780 *
781 * @param _dev		the parent device of @p _child
782 * @param _child	the device to which the tag will belong
783 */
784METHOD bus_dma_tag_t get_dma_tag {
785	device_t	_dev;
786	device_t	_child;
787} DEFAULT bus_generic_get_dma_tag;
788
789/**
790 * @brief Returns bus_space_tag_t for use w/ devices on the bus.
791 *
792 * @param _dev		the parent device of @p _child
793 * @param _child	the device to which the tag will belong
794 */
795METHOD bus_space_tag_t get_bus_tag {
796	device_t	_dev;
797	device_t	_child;
798} DEFAULT bus_generic_get_bus_tag;
799
800/**
801 * @brief Allow the bus to determine the unit number of a device.
802 *
803 * @param _dev		the parent device of @p _child
804 * @param _child	the device whose unit is to be wired
805 * @param _name		the name of the device's new devclass
806 * @param _unitp	a pointer to the device's new unit value
807 */
808METHOD void hint_device_unit {
809	device_t	_dev;
810	device_t	_child;
811	const char	*_name;
812	int		*_unitp;
813};
814
815/**
816 * @brief Notify a bus that the bus pass level has been changed
817 *
818 * @param _dev		the bus device
819 */
820METHOD void new_pass {
821	device_t	_dev;
822} DEFAULT bus_generic_new_pass;
823
824/**
825 * @brief Notify a bus that specified child's IRQ should be remapped.
826 *
827 * @param _dev		the bus device
828 * @param _child	the child device
829 * @param _irq		the irq number
830 */
831METHOD int remap_intr {
832	device_t	_dev;
833	device_t	_child;
834	u_int		_irq;
835} DEFAULT null_remap_intr;
836
837/**
838 * @brief Suspend a given child
839 *
840 * @param _dev		the parent device of @p _child
841 * @param _child	the device to suspend
842 */
843METHOD int suspend_child {
844	device_t	_dev;
845	device_t	_child;
846} DEFAULT bus_generic_suspend_child;
847
848/**
849 * @brief Resume a given child
850 *
851 * @param _dev		the parent device of @p _child
852 * @param _child	the device to resume
853 */
854METHOD int resume_child {
855	device_t	_dev;
856	device_t	_child;
857} DEFAULT bus_generic_resume_child;
858
859/**
860 * @brief Get the VM domain handle for the given bus and child.
861 *
862 * @param _dev		the bus device
863 * @param _child	the child device
864 * @param _domain	a pointer to the bus's domain handle identifier
865 */
866METHOD int get_domain {
867	device_t	_dev;
868	device_t	_child;
869	int		*_domain;
870} DEFAULT bus_generic_get_domain;
871
872/**
873 * @brief Request a set of CPUs
874 *
875 * @param _dev		the bus device
876 * @param _child	the child device
877 * @param _op		type of CPUs to request
878 * @param _setsize	the size of the set passed in _cpuset
879 * @param _cpuset	a pointer to a cpuset to receive the requested
880 *			set of CPUs
881 */
882METHOD int get_cpus {
883	device_t	_dev;
884	device_t	_child;
885	enum cpu_sets	_op;
886	size_t		_setsize;
887	struct _cpuset	*_cpuset;
888} DEFAULT bus_generic_get_cpus;
889
890/**
891 * @brief Prepares the given child of the bus for reset
892 *
893 * Typically bus detaches or suspends children' drivers, and then
894 * calls this method to save bus-specific information, for instance,
895 * PCI config space, which is damaged by reset.
896 *
897 * The bus_helper_reset_prepare() helper is provided to ease
898 * implementing bus reset methods.
899 *
900 * @param _dev		the bus device
901 * @param _child	the child device
902 */
903METHOD int reset_prepare {
904	device_t _dev;
905	device_t _child;
906} DEFAULT null_reset_prepare;
907
908/**
909 * @brief Restores the child operations after the reset
910 *
911 * The bus_helper_reset_post() helper is provided to ease
912 * implementing bus reset methods.
913 *
914 * @param _dev		the bus device
915 * @param _child	the child device
916 */
917METHOD int reset_post {
918	device_t _dev;
919	device_t _child;
920} DEFAULT null_reset_post;
921
922/**
923 * @brief Performs reset of the child
924 *
925 * @param _dev		the bus device
926 * @param _child	the child device
927 * @param _flags	DEVF_RESET_ flags
928 */
929METHOD int reset_child {
930	device_t _dev;
931	device_t _child;
932	int _flags;
933};
934
935/**
936 * @brief Gets child's specific property
937 *
938 * The bus_get_property can be used to access device
939 * specific properties stored on the bus. If _propvalue
940 * is NULL or _size is 0, then method only returns size
941 * of the property.
942 *
943 * @param _dev			the bus device
944 * @param _child		the child device
945 * @param _propname		property name
946 * @param _propvalue	property value destination
947 * @param _size			property value size
948 *
949 * @returns size of property if successful otherwise -1
950 */
951METHOD ssize_t get_property {
952	device_t _dev;
953	device_t _child;
954	const char *_propname;
955	void *_propvalue;
956	size_t _size;
957} DEFAULT null_get_property;
958