xref: /freebsd/share/man/man9/BUS_SETUP_INTR.9 (revision d056fa046c6a91b90cd98165face0e42a33a5173)
1.\" Copyright (c) 2000 Jeroen Ruigrok van der Werven
2.\" All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\"    notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\"    notice, this list of conditions and the following disclaimer in the
11.\"    documentation and/or other materials provided with the distribution.
12.\"
13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23.\" SUCH DAMAGE.
24.\"
25.\" $FreeBSD$
26.\"
27.Dd January 6, 2005
28.Dt BUS_SETUP_INTR 9
29.Os
30.Sh NAME
31.Nm BUS_SETUP_INTR ,
32.Nm bus_setup_intr ,
33.Nm BUS_TEARDOWN_INTR ,
34.Nm bus_teardown_intr
35.Nd create, attach and teardown an interrupt handler
36.Sh SYNOPSIS
37.In sys/param.h
38.In sys/bus.h
39.Ft int
40.Fn BUS_SETUP_INTR "device_t dev" "device_t child" "struct resource *irq" "int flags" "driver_intr_t *intr" "void *arg" "void **cookiep"
41.Ft int
42.Fn bus_setup_intr "device_t dev" "struct resource *r" "int flags" "driver_intr_t handler" "void *arg" "void **cookiep"
43.Ft int
44.Fn BUS_TEARDOWN_INTR "device_t dev" "device_t child" "struct resource *irq" "void *cookiep"
45.Ft int
46.Fn bus_teardown_intr "device_t dev" "struct resource *r" "void *cookiep"
47.Sh DESCRIPTION
48The
49.Fn BUS_SETUP_INTR
50method
51will create and attach an interrupt handler to an interrupt
52previously allocated by the resource manager's
53.Xr BUS_ALLOC_RESOURCE 9
54method.
55The
56.Fa flags
57are found in
58.In sys/bus.h ,
59and give the broad category of interrupt.
60The
61.Fa flags
62also tell the interrupt handlers about certain
63device driver characteristics.
64.Dv INTR_FAST
65means the handler is for a timing-critical function.
66Extra care is take to speed up these handlers.
67Use of this implies
68.Dv INTR_EXCL .
69.Dv INTR_EXCL
70marks the handler as being
71an exclusive handler for this interrupt.
72.Dv INTR_MPSAFE
73tells the scheduler that the interrupt handler
74is well behaved in a preemptive environment
75(``SMP safe''),
76and does not need
77to be protected by the ``Giant Lock'' mutex.
78.Dv INTR_ENTROPY
79marks the interrupt as being a good source of entropy -
80this may be used by the entropy device
81.Pa /dev/random .
82The handler
83.Fa intr
84will be called with the value
85.Fa arg
86as its only argument.
87.Pp
88The
89.Fa cookiep
90argument is a pointer to a
91.Vt "void *"
92that
93.Fn BUS_SETUP_INTR
94will write a cookie for the parent bus' use to if it is successful in
95establishing an interrupt.
96Driver writers may assume that this cookie will be non-zero.
97The nexus driver will write 0 on failure to
98.Fa cookiep .
99.Pp
100The interrupt handler will be detached by
101.Fn BUS_TEARDOWN_INTR .
102The cookie needs to be passed to
103.Fn BUS_TEARDOWN_INTR
104in order to tear down the correct interrupt handler.
105Once
106.Fn BUS_TEARDOWN_INTR
107returns, it is guaranteed that the interrupt function is not active and
108will no longer be called.
109.Pp
110Mutexes are not allowed to be held across calls to these functions.
111.Sh RETURN VALUES
112Zero is returned on success,
113otherwise an appropriate error is returned.
114.Sh SEE ALSO
115.Xr random 4 ,
116.Xr device 9 ,
117.Xr driver 9
118.Sh AUTHORS
119.An -nosplit
120This manual page was written by
121.An Jeroen Ruigrok van der Werven
122.Aq asmodai@FreeBSD.org
123based on the manual pages for
124.Fn BUS_CREATE_INTR
125and
126.Fn BUS_CONNECT_INTR
127written by
128.An Doug Rabson
129.Aq dfr@FreeBSD.org .
130