xref: /freebsd/sys/kern/bus_if.m (revision 7979205e0553ed23b61faa473d9dd866872cb710)
1#-
2# Copyright (c) 1998-2004 Doug Rabson
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27
28#include <sys/types.h>
29#include <sys/systm.h>
30#include <sys/bus.h>
31
32/**
33 * @defgroup BUS bus - KObj methods for drivers of devices with children
34 * @brief A set of methods required device drivers that support
35 * child devices.
36 * @{
37 */
38INTERFACE bus;
39
40#
41# Default implementations of some methods.
42#
43CODE {
44	static struct resource *
45	null_alloc_resource(device_t dev, device_t child,
46	    int type, int *rid, rman_res_t start, rman_res_t end,
47	    rman_res_t count, u_int flags)
48	{
49	    return (0);
50	}
51
52	static int
53	null_remap_intr(device_t bus, device_t dev, u_int irq)
54	{
55
56		if (dev != NULL)
57			return (BUS_REMAP_INTR(dev, NULL, irq));
58		return (ENXIO);
59	}
60
61	static device_t
62	null_add_child(device_t bus, int order, const char *name,
63	    int unit)
64	{
65
66		panic("%s: bus_add_child is not implemented, name '%s', "
67		    "unit %d", device_get_nameunit(bus), name, unit);
68	}
69
70	static int
71	null_reset_post(device_t bus, device_t dev)
72	{
73		return (0);
74	}
75
76	static int
77	null_reset_prepare(device_t bus, device_t dev)
78	{
79		return (0);
80	}
81
82	static struct rman *
83	null_get_rman(device_t bus, int type, u_int flags)
84	{
85		return (NULL);
86	}
87
88	static struct resource_list *
89	null_get_resource_list(device_t bus, device_t dev)
90	{
91		return (NULL);
92	}
93};
94
95/**
96 * @brief Print a description of a child device
97 *
98 * This is called from system code which prints out a description of a
99 * device. It should describe the attachment that the child has with
100 * the parent. For instance the TurboLaser bus prints which node the
101 * device is attached to. See bus_generic_print_child() for more
102 * information.
103 *
104 * @param _dev		the device whose child is being printed
105 * @param _child	the child device to describe
106 *
107 * @returns		the number of characters output.
108 */
109METHOD int print_child {
110	device_t _dev;
111	device_t _child;
112} DEFAULT bus_generic_print_child;
113
114/**
115 * @brief Print a notification about an unprobed child device.
116 *
117 * Called for each child device that did not succeed in probing for a
118 * driver.
119 *
120 * @param _dev		the device whose child was being probed
121 * @param _child	the child device which failed to probe
122 */
123METHOD void probe_nomatch {
124        device_t _dev;
125        device_t _child;
126};
127
128/**
129 * @brief Read the value of a bus-specific attribute of a device
130 *
131 * This method, along with BUS_WRITE_IVAR() manages a bus-specific set
132 * of instance variables of a child device.  The intention is that
133 * each different type of bus defines a set of appropriate instance
134 * variables (such as ports and irqs for ISA bus etc.)
135 *
136 * This information could be given to the child device as a struct but
137 * that makes it hard for a bus to add or remove variables without
138 * forcing an edit and recompile for all drivers which may not be
139 * possible for vendor supplied binary drivers.
140 *
141 * This method copies the value of an instance variable to the
142 * location specified by @p *_result.
143 *
144 * @param _dev		the device whose child was being examined
145 * @param _child	the child device whose instance variable is
146 *			being read
147 * @param _index	the instance variable to read
148 * @param _result	a location to receive the instance variable
149 *			value
150 *
151 * @retval 0		success
152 * @retval ENOENT	no such instance variable is supported by @p
153 *			_dev
154 */
155METHOD int read_ivar {
156	device_t _dev;
157	device_t _child;
158	int _index;
159	uintptr_t *_result;
160};
161
162/**
163 * @brief Write the value of a bus-specific attribute of a device
164 *
165 * This method sets the value of an instance variable to @p _value.
166 *
167 * @param _dev		the device whose child was being updated
168 * @param _child	the child device whose instance variable is
169 *			being written
170 * @param _index	the instance variable to write
171 * @param _value	the value to write to that instance variable
172 *
173 * @retval 0		success
174 * @retval ENOENT	no such instance variable is supported by @p
175 *			_dev
176 * @retval EINVAL	the instance variable was recognised but
177 *			contains a read-only value
178 */
179METHOD int write_ivar {
180	device_t _dev;
181	device_t _child;
182	int _indx;
183	uintptr_t _value;
184};
185
186/**
187 * @brief Notify a bus that a child was deleted
188 *
189 * Called at the beginning of device_delete_child() to allow the parent
190 * to teardown any bus-specific state for the child.
191 *
192 * @param _dev		the device whose child is being deleted
193 * @param _child	the child device which is being deleted
194 */
195METHOD void child_deleted {
196	device_t _dev;
197	device_t _child;
198};
199
200/**
201 * @brief Notify a bus that a child was detached
202 *
203 * Called after the child's DEVICE_DETACH() method to allow the parent
204 * to reclaim any resources allocated on behalf of the child.
205 *
206 * @param _dev		the device whose child changed state
207 * @param _child	the child device which changed state
208 */
209METHOD void child_detached {
210	device_t _dev;
211	device_t _child;
212};
213
214/**
215 * @brief Notify a bus that a new driver was added
216 *
217 * Called when a new driver is added to the devclass which owns this
218 * bus. The generic implementation of this method attempts to probe and
219 * attach any un-matched children of the bus.
220 *
221 * @param _dev		the device whose devclass had a new driver
222 *			added to it
223 * @param _driver	the new driver which was added
224 */
225METHOD void driver_added {
226	device_t _dev;
227	driver_t *_driver;
228} DEFAULT bus_generic_driver_added;
229
230/**
231 * @brief Create a new child device
232 *
233 * For buses which use use drivers supporting DEVICE_IDENTIFY() to
234 * enumerate their devices, this method is used to create new
235 * device instances. The new device will be added after the last
236 * existing child with the same order. Implementations of bus_add_child
237 * call device_add_child_ordered to add the child and often add
238 * a suitable ivar to the device specific to that bus.
239 *
240 * @param _dev		the bus device which will be the parent of the
241 *			new child device
242 * @param _order	a value which is used to partially sort the
243 *			children of @p _dev - devices created using
244 *			lower values of @p _order appear first in @p
245 *			_dev's list of children
246 * @param _name		devclass name for new device or @c NULL if not
247 *			specified
248 * @param _unit		unit number for new device or @c -1 if not
249 *			specified
250 */
251METHOD device_t add_child {
252	device_t _dev;
253	u_int _order;
254	const char *_name;
255	int _unit;
256} DEFAULT null_add_child;
257
258/**
259 * @brief Rescan the bus
260 *
261 * This method is called by a parent bridge or devctl to trigger a bus
262 * rescan.  The rescan should delete devices no longer present and
263 * enumerate devices that have newly arrived.
264 *
265 * @param _dev		the bus device
266 */
267METHOD int rescan {
268	device_t _dev;
269} DEFAULT bus_null_rescan;
270
271/**
272 * @brief Allocate a system resource
273 *
274 * This method is called by child devices of a bus to allocate resources.
275 * The types are defined in <machine/resource.h>; the meaning of the
276 * resource-ID field varies from bus to bus (but @p *rid == 0 is always
277 * valid if the resource type is). If a resource was allocated and the
278 * caller did not use the RF_ACTIVE to specify that it should be
279 * activated immediately, the caller is responsible for calling
280 * BUS_ACTIVATE_RESOURCE() when it actually uses the resource.
281 *
282 * @param _dev		the parent device of @p _child
283 * @param _child	the device which is requesting an allocation
284 * @param _type		the type of resource to allocate
285 * @param _rid		a pointer to the resource identifier
286 * @param _start	hint at the start of the resource range - pass
287 *			@c 0 for any start address
288 * @param _end		hint at the end of the resource range - pass
289 *			@c ~0 for any end address
290 * @param _count	hint at the size of range required - pass @c 1
291 *			for any size
292 * @param _flags	any extra flags to control the resource
293 *			allocation - see @c RF_XXX flags in
294 *			<sys/rman.h> for details
295 *
296 * @returns		the resource which was allocated or @c NULL if no
297 *			resource could be allocated
298 */
299METHOD struct resource * alloc_resource {
300	device_t	_dev;
301	device_t	_child;
302	int		_type;
303	int	       *_rid;
304	rman_res_t	_start;
305	rman_res_t	_end;
306	rman_res_t	_count;
307	u_int		_flags;
308} DEFAULT null_alloc_resource;
309
310/**
311 * @brief Activate a resource
312 *
313 * Activate a resource previously allocated with
314 * BUS_ALLOC_RESOURCE().  This may enable decoding of this resource in a
315 * device for instance.  It will also establish a mapping for the resource
316 * unless RF_UNMAPPED was set when allocating the resource.
317 *
318 * @param _dev		the parent device of @p _child
319 * @param _child	the device which allocated the resource
320 * @param _r		the resource to activate
321 */
322METHOD int activate_resource {
323	device_t	_dev;
324	device_t	_child;
325	struct resource *_r;
326};
327
328
329/**
330 * @brief Map a resource
331 *
332 * Allocate a mapping for a range of an active resource.  The mapping
333 * is described by a struct resource_map object.  This may for instance
334 * map a memory region into the kernel's virtual address space.
335 *
336 * @param _dev		the parent device of @p _child
337 * @param _child	the device which allocated the resource
338 * @param _r		the resource to map
339 * @param _args		optional attributes of the mapping
340 * @param _map		the mapping
341 */
342METHOD int map_resource {
343	device_t	_dev;
344	device_t	_child;
345	struct resource *_r;
346	struct resource_map_request *_args;
347	struct resource_map *_map;
348} DEFAULT bus_generic_map_resource;
349
350
351/**
352 * @brief Unmap a resource
353 *
354 * Release a mapping previously allocated with
355 * BUS_MAP_RESOURCE(). This may for instance unmap a memory region
356 * from the kernel's virtual address space.
357 *
358 * @param _dev		the parent device of @p _child
359 * @param _child	the device which allocated the resource
360 * @param _r		the resource
361 * @param _map		the mapping to release
362 */
363METHOD int unmap_resource {
364	device_t	_dev;
365	device_t	_child;
366	struct resource *_r;
367	struct resource_map *_map;
368} DEFAULT bus_generic_unmap_resource;
369
370
371/**
372 * @brief Deactivate a resource
373 *
374 * Deactivate a resource previously allocated with
375 * BUS_ALLOC_RESOURCE().
376 *
377 * @param _dev		the parent device of @p _child
378 * @param _child	the device which allocated the resource
379 * @param _r		the resource to deactivate
380 */
381METHOD int deactivate_resource {
382	device_t	_dev;
383	device_t	_child;
384	struct resource *_r;
385};
386
387/**
388 * @brief Adjust a resource
389 *
390 * Adjust the start and/or end of a resource allocated by
391 * BUS_ALLOC_RESOURCE.  At least part of the new address range must overlap
392 * with the existing address range.  If the successful, the resource's range
393 * will be adjusted to [start, end] on return.
394 *
395 * @param _dev		the parent device of @p _child
396 * @param _child	the device which allocated the resource
397 * @param _res		the resource to adjust
398 * @param _start	the new starting address of the resource range
399 * @param _end		the new ending address of the resource range
400 */
401METHOD int adjust_resource {
402	device_t	_dev;
403	device_t	_child;
404	struct resource *_res;
405	rman_res_t	_start;
406	rman_res_t	_end;
407};
408
409/**
410 * @brief translate a resource value
411 *
412 * Give a bus driver the opportunity to translate resource ranges.  If
413 * successful, the host's view of the resource starting at @p _start is
414 * returned in @p _newstart, otherwise an error is returned.
415 *
416 * @param _dev		the device associated with the resource
417 * @param _type		the type of resource
418 * @param _start	the starting address of the resource range
419 * @param _newstart	the new starting address of the resource range
420 */
421METHOD int translate_resource {
422	device_t	_dev;
423	int		_type;
424	rman_res_t	_start;
425	rman_res_t	*_newstart;
426} DEFAULT bus_generic_translate_resource;
427
428/**
429 * @brief Release a resource
430 *
431 * Free a resource allocated by the BUS_ALLOC_RESOURCE.  The @p _rid
432 * value must be the same as the one returned by BUS_ALLOC_RESOURCE()
433 * (which is not necessarily the same as the one the client passed).
434 *
435 * @param _dev		the parent device of @p _child
436 * @param _child	the device which allocated the resource
437 * @param _r		the resource to release
438 */
439METHOD int release_resource {
440	device_t	_dev;
441	device_t	_child;
442	struct resource *_res;
443};
444
445/**
446 * @brief Install an interrupt handler
447 *
448 * This method is used to associate an interrupt handler function with
449 * an irq resource. When the interrupt triggers, the function @p _intr
450 * will be called with the value of @p _arg as its single
451 * argument. The value returned in @p *_cookiep is used to cancel the
452 * interrupt handler - the caller should save this value to use in a
453 * future call to BUS_TEARDOWN_INTR().
454 *
455 * @param _dev		the parent device of @p _child
456 * @param _child	the device which allocated the resource
457 * @param _irq		the resource representing the interrupt
458 * @param _flags	a set of bits from enum intr_type specifying
459 *			the class of interrupt
460 * @param _intr		the function to call when the interrupt
461 *			triggers
462 * @param _arg		a value to use as the single argument in calls
463 *			to @p _intr
464 * @param _cookiep	a pointer to a location to receive a cookie
465 *			value that may be used to remove the interrupt
466 *			handler
467 */
468METHOD int setup_intr {
469	device_t	_dev;
470	device_t	_child;
471	struct resource *_irq;
472	int		_flags;
473	driver_filter_t	*_filter;
474	driver_intr_t	*_intr;
475	void		*_arg;
476	void		**_cookiep;
477};
478
479/**
480 * @brief Uninstall an interrupt handler
481 *
482 * This method is used to disassociate an interrupt handler function
483 * with an irq resource. The value of @p _cookie must be the value
484 * returned from a previous call to BUS_SETUP_INTR().
485 *
486 * @param _dev		the parent device of @p _child
487 * @param _child	the device which allocated the resource
488 * @param _irq		the resource representing the interrupt
489 * @param _cookie	the cookie value returned when the interrupt
490 *			was originally registered
491 */
492METHOD int teardown_intr {
493	device_t	_dev;
494	device_t	_child;
495	struct resource	*_irq;
496	void		*_cookie;
497};
498
499/**
500 * @brief Suspend an interrupt handler
501 *
502 * This method is used to mark a handler as suspended in the case
503 * that the associated device is powered down and cannot be a source
504 * for the, typically shared, interrupt.
505 * The value of @p _irq must be the interrupt resource passed
506 * to a previous call to BUS_SETUP_INTR().
507 *
508 * @param _dev		the parent device of @p _child
509 * @param _child	the device which allocated the resource
510 * @param _irq		the resource representing the interrupt
511 */
512METHOD int suspend_intr {
513	device_t	_dev;
514	device_t	_child;
515	struct resource *_irq;
516} DEFAULT bus_generic_suspend_intr;
517
518/**
519 * @brief Resume an interrupt handler
520 *
521 * This method is used to clear suspended state of a handler when
522 * the associated device is powered up and can be an interrupt source
523 * again.
524 * The value of @p _irq must be the interrupt resource passed
525 * to a previous call to BUS_SETUP_INTR().
526 *
527 * @param _dev		the parent device of @p _child
528 * @param _child	the device which allocated the resource
529 * @param _irq		the resource representing the interrupt
530 */
531METHOD int resume_intr {
532	device_t	_dev;
533	device_t	_child;
534	struct resource *_irq;
535} DEFAULT bus_generic_resume_intr;
536
537/**
538 * @brief Define a resource which can be allocated with
539 * BUS_ALLOC_RESOURCE().
540 *
541 * This method is used by some buses (typically ISA) to allow a
542 * driver to describe a resource range that it would like to
543 * allocate. The resource defined by @p _type and @p _rid is defined
544 * to start at @p _start and to include @p _count indices in its
545 * range.
546 *
547 * @param _dev		the parent device of @p _child
548 * @param _child	the device which owns the resource
549 * @param _type		the type of resource
550 * @param _rid		the resource identifier
551 * @param _start	the start of the resource range
552 * @param _count	the size of the resource range
553 */
554METHOD int set_resource {
555	device_t	_dev;
556	device_t	_child;
557	int		_type;
558	int		_rid;
559	rman_res_t	_start;
560	rman_res_t	_count;
561};
562
563/**
564 * @brief Describe a resource
565 *
566 * This method allows a driver to examine the range used for a given
567 * resource without actually allocating it.
568 *
569 * @param _dev		the parent device of @p _child
570 * @param _child	the device which owns the resource
571 * @param _type		the type of resource
572 * @param _rid		the resource identifier
573 * @param _start	the address of a location to receive the start
574 *			index of the resource range
575 * @param _count	the address of a location to receive the size
576 *			of the resource range
577 */
578METHOD int get_resource {
579	device_t	_dev;
580	device_t	_child;
581	int		_type;
582	int		_rid;
583	rman_res_t	*_startp;
584	rman_res_t	*_countp;
585};
586
587/**
588 * @brief Delete a resource.
589 *
590 * Use this to delete a resource (possibly one previously added with
591 * BUS_SET_RESOURCE()).
592 *
593 * @param _dev		the parent device of @p _child
594 * @param _child	the device which owns the resource
595 * @param _type		the type of resource
596 * @param _rid		the resource identifier
597 */
598METHOD void delete_resource {
599	device_t	_dev;
600	device_t	_child;
601	int		_type;
602	int		_rid;
603};
604
605/**
606 * @brief Return a struct resource_list.
607 *
608 * Used by drivers which use bus_generic_rl_alloc_resource() etc. to
609 * implement their resource handling. It should return the resource
610 * list of the given child device.
611 *
612 * @param _dev		the parent device of @p _child
613 * @param _child	the device which owns the resource list
614 */
615METHOD struct resource_list * get_resource_list {
616	device_t	_dev;
617	device_t	_child;
618} DEFAULT null_get_resource_list;
619
620/**
621 * @brief Return a struct rman.
622 *
623 * Used by drivers which use bus_generic_rman_alloc_resource() etc. to
624 * implement their resource handling. It should return the resource
625 * manager used for the given resource type.
626 *
627 * @param _dev		the bus device
628 * @param _type		the resource type
629 * @param _flags	resource flags (@c RF_XXX flags in
630 *			<sys/rman.h>)
631 */
632METHOD struct rman * get_rman {
633	device_t	_dev;
634	int		_type;
635	u_int		_flags;
636} DEFAULT null_get_rman;
637
638/**
639 * @brief Is the hardware described by @p _child still attached to the
640 * system?
641 *
642 * This method should return 0 if the device is not present.  It
643 * should return -1 if it is present.  Any errors in determining
644 * should be returned as a normal errno value.  Client drivers are to
645 * assume that the device is present, even if there is an error
646 * determining if it is there.  Buses are to try to avoid returning
647 * errors, but newcard will return an error if the device fails to
648 * implement this method.
649 *
650 * @param _dev		the parent device of @p _child
651 * @param _child	the device which is being examined
652 */
653METHOD int child_present {
654	device_t	_dev;
655	device_t	_child;
656} DEFAULT bus_generic_child_present;
657
658/**
659 * @brief Returns the pnp info for this device.
660 *
661 * Return it as a string, appended to @p _sb
662 *
663 * The string must be formatted as a space-separated list of
664 * name=value pairs.  Names may only contain alphanumeric characters,
665 * underscores ('_') and hyphens ('-').  Values can contain any
666 * non-whitespace characters.  Values containing whitespace can be
667 * quoted with double quotes ('"').  Double quotes and backslashes in
668 * quoted values can be escaped with backslashes ('\').
669 *
670 * @param _dev		the parent device of @p _child
671 * @param _child	the device which is being examined
672 * @param _sb		sbuf for results string
673 */
674METHOD int child_pnpinfo {
675	device_t	_dev;
676	device_t	_child;
677	struct sbuf	*_sb;
678} DEFAULT bus_generic_child_pnpinfo;
679
680/**
681 * @brief Returns the location for this device.
682 *
683 * Return it as a string, appended to @p _sb
684 *
685 * The string must be formatted as a space-separated list of
686 * name=value pairs.  Names may only contain alphanumeric characters,
687 * underscores ('_') and hyphens ('-').  Values can contain any
688 * non-whitespace characters.  Values containing whitespace can be
689 * quoted with double quotes ('"').  Double quotes and backslashes in
690 * quoted values can be escaped with backslashes ('\').
691 *
692 * @param _dev		the parent device of @p _child
693 * @param _child	the device which is being examined
694 * @param _sb		sbuf for results string
695 */
696METHOD int child_location {
697	device_t	_dev;
698	device_t	_child;
699	struct sbuf	*_sb;
700} DEFAULT bus_generic_child_location;
701
702/**
703 * @brief Allow drivers to request that an interrupt be bound to a specific
704 * CPU.
705 *
706 * @param _dev		the parent device of @p _child
707 * @param _child	the device which allocated the resource
708 * @param _irq		the resource representing the interrupt
709 * @param _cpu		the CPU to bind the interrupt to
710 */
711METHOD int bind_intr {
712	device_t	_dev;
713	device_t	_child;
714	struct resource *_irq;
715	int		_cpu;
716} DEFAULT bus_generic_bind_intr;
717
718/**
719 * @brief Allow (bus) drivers to specify the trigger mode and polarity
720 * of the specified interrupt.
721 *
722 * @param _dev		the bus device
723 * @param _irq		the interrupt number to modify
724 * @param _trig		the trigger mode required
725 * @param _pol		the interrupt polarity required
726 */
727METHOD int config_intr {
728	device_t	_dev;
729	int		_irq;
730	enum intr_trigger _trig;
731	enum intr_polarity _pol;
732} DEFAULT bus_generic_config_intr;
733
734/**
735 * @brief Allow drivers to associate a description with an active
736 * interrupt handler.
737 *
738 * @param _dev		the parent device of @p _child
739 * @param _child	the device which allocated the resource
740 * @param _irq		the resource representing the interrupt
741 * @param _cookie	the cookie value returned when the interrupt
742 *			was originally registered
743 * @param _descr	the description to associate with the interrupt
744 */
745METHOD int describe_intr {
746	device_t	_dev;
747	device_t	_child;
748	struct resource *_irq;
749	void		*_cookie;
750	const char	*_descr;
751} DEFAULT bus_generic_describe_intr;
752
753/**
754 * @brief Notify a (bus) driver about a child that the hints mechanism
755 * believes it has discovered.
756 *
757 * The bus is responsible for then adding the child in the right order
758 * and discovering other things about the child.  The bus driver is
759 * free to ignore this hint, to do special things, etc.  It is all up
760 * to the bus driver to interpret.
761 *
762 * This method is only called in response to the parent bus asking for
763 * hinted devices to be enumerated.
764 *
765 * @param _dev		the bus device
766 * @param _dname	the name of the device w/o unit numbers
767 * @param _dunit	the unit number of the device
768 */
769METHOD void hinted_child {
770	device_t	_dev;
771	const char	*_dname;
772	int		_dunit;
773};
774
775/**
776 * @brief Returns bus_dma_tag_t for use w/ devices on the bus.
777 *
778 * @param _dev		the parent device of @p _child
779 * @param _child	the device to which the tag will belong
780 */
781METHOD bus_dma_tag_t get_dma_tag {
782	device_t	_dev;
783	device_t	_child;
784} DEFAULT bus_generic_get_dma_tag;
785
786/**
787 * @brief Returns bus_space_tag_t for use w/ devices on the bus.
788 *
789 * @param _dev		the parent device of @p _child
790 * @param _child	the device to which the tag will belong
791 */
792METHOD bus_space_tag_t get_bus_tag {
793	device_t	_dev;
794	device_t	_child;
795} DEFAULT bus_generic_get_bus_tag;
796
797/**
798 * @brief Allow the bus to determine the unit number of a device.
799 *
800 * @param _dev		the parent device of @p _child
801 * @param _child	the device whose unit is to be wired
802 * @param _name		the name of the device's new devclass
803 * @param _unitp	a pointer to the device's new unit value
804 */
805METHOD void hint_device_unit {
806	device_t	_dev;
807	device_t	_child;
808	const char	*_name;
809	int		*_unitp;
810};
811
812/**
813 * @brief Notify a bus that the bus pass level has been changed
814 *
815 * @param _dev		the bus device
816 */
817METHOD void new_pass {
818	device_t	_dev;
819} DEFAULT bus_generic_new_pass;
820
821/**
822 * @brief Notify a bus that specified child's IRQ should be remapped.
823 *
824 * @param _dev		the bus device
825 * @param _child	the child device
826 * @param _irq		the irq number
827 */
828METHOD int remap_intr {
829	device_t	_dev;
830	device_t	_child;
831	u_int		_irq;
832} DEFAULT null_remap_intr;
833
834/**
835 * @brief Suspend a given child
836 *
837 * @param _dev		the parent device of @p _child
838 * @param _child	the device to suspend
839 */
840METHOD int suspend_child {
841	device_t	_dev;
842	device_t	_child;
843} DEFAULT bus_generic_suspend_child;
844
845/**
846 * @brief Resume a given child
847 *
848 * @param _dev		the parent device of @p _child
849 * @param _child	the device to resume
850 */
851METHOD int resume_child {
852	device_t	_dev;
853	device_t	_child;
854} DEFAULT bus_generic_resume_child;
855
856/**
857 * @brief Get the VM domain handle for the given bus and child.
858 *
859 * @param _dev		the bus device
860 * @param _child	the child device
861 * @param _domain	a pointer to the bus's domain handle identifier
862 */
863METHOD int get_domain {
864	device_t	_dev;
865	device_t	_child;
866	int		*_domain;
867} DEFAULT bus_generic_get_domain;
868
869/**
870 * @brief Request a set of CPUs
871 *
872 * @param _dev		the bus device
873 * @param _child	the child device
874 * @param _op		type of CPUs to request
875 * @param _setsize	the size of the set passed in _cpuset
876 * @param _cpuset	a pointer to a cpuset to receive the requested
877 *			set of CPUs
878 */
879METHOD int get_cpus {
880	device_t	_dev;
881	device_t	_child;
882	enum cpu_sets	_op;
883	size_t		_setsize;
884	struct _cpuset	*_cpuset;
885} DEFAULT bus_generic_get_cpus;
886
887/**
888 * @brief Prepares the given child of the bus for reset
889 *
890 * Typically bus detaches or suspends children' drivers, and then
891 * calls this method to save bus-specific information, for instance,
892 * PCI config space, which is damaged by reset.
893 *
894 * The bus_helper_reset_prepare() helper is provided to ease
895 * implementing bus reset methods.
896 *
897 * @param _dev		the bus device
898 * @param _child	the child device
899 */
900METHOD int reset_prepare {
901	device_t _dev;
902	device_t _child;
903} DEFAULT null_reset_prepare;
904
905/**
906 * @brief Restores the child operations after the reset
907 *
908 * The bus_helper_reset_post() helper is provided to ease
909 * implementing bus reset methods.
910 *
911 * @param _dev		the bus device
912 * @param _child	the child device
913 */
914METHOD int reset_post {
915	device_t _dev;
916	device_t _child;
917} DEFAULT null_reset_post;
918
919/**
920 * @brief Performs reset of the child
921 *
922 * @param _dev		the bus device
923 * @param _child	the child device
924 * @param _flags	DEVF_RESET_ flags
925 */
926METHOD int reset_child {
927	device_t _dev;
928	device_t _child;
929	int _flags;
930};
931
932/**
933 * @brief Gets child's specific property
934 *
935 * The bus_get_property can be used to access device
936 * specific properties stored on the bus. If _propvalue
937 * is NULL or _size is 0, then method only returns size
938 * of the property.
939 *
940 * @param _dev			the bus device
941 * @param _child		the child device
942 * @param _propname		property name
943 * @param _propvalue	property value destination
944 * @param _size			property value size
945 *
946 * @returns size of property if successful otherwise -1
947 */
948METHOD ssize_t get_property {
949	device_t _dev;
950	device_t _child;
951	const char *_propname;
952	void *_propvalue;
953	size_t _size;
954	device_property_type_t type;
955} DEFAULT bus_generic_get_property;
956
957/**
958 * @brief Gets a child's full path to the device
959 *
960 * The get_device_path method retrieves a device's
961 * full path to the device using one of several
962 * locators present in the system.
963 *
964 * @param _bus			the bus device
965 * @param _child		the child device
966 * @param _locator		locator name
967 * @param _sb			buffer loaction string
968 */
969METHOD int get_device_path {
970	device_t _bus;
971	device_t _child;
972	const char *_locator;
973	struct sbuf *_sb;
974} DEFAULT bus_generic_get_device_path;
975