xref: /netbsd-src/share/man/man4/intersil7170.4 (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1.\"	$NetBSD: intersil7170.4,v 1.11 2006/10/04 17:55:54 wiz Exp $
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3.\" Copyright (c) 2000 The NetBSD Foundation, Inc.
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6.\" This code is derived from software contributed to The NetBSD Foundation
7.\" by Paul Kranenburg.
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37.Dd October 1, 2006
38.Dt INTERSIL7170 4
39.Os
40.Sh NAME
41.Nm intersil7170
42.Nd
43.Tn Intersil ICM7170 time-of-day clock driver
44.Sh SYNOPSIS
45.In dev/ic/intersil7170reg.h
46.In dev/ic/intersil7170var.h
47.Cd "define intersil7170"
48.Cd "file   dev/ic/intersil7170.c    intersil7170"
49.Sh DESCRIPTION
50The
51.Nm
52driver provides access to the
53.Tn Intersil ICM7170
54time-of-day clock chip.
55Access methods to retrieve and set date and time
56are provided through the
57.Em TODR
58interface defined in
59.Xr todr 9 .
60.Pp
61To tie an instance of this device to the system, use the
62.Fn intersil7170_attach
63function and the
64.Fa intersil7170_softc
65structure defined as follows:
66.Pp
67.Ft "void"
68.Fn intersil7170_attach "struct intersil7170_softc *"
69.Pp
70.Bd -literal
71struct intersil7170_softc {
72	struct device	sc_dev;
73	bus_space_tag_t	sc_bst;
74	bus_space_handle_t sc_bsh;
75	struct todr_chip_handle sc_handle;
76	u_int		sc_year0;
77	u_int		sc_flag;
78};
79.Ed
80.Pp
81.Bl -tag -width Dv -offset indent
82.It Fa bus_tag
83.It Fa bus_handle
84Specify bus space access to the chip's non-volatile memory
85.Pq including the clock registers .
86.It Fa sc_handle
87TODR handle passed to the
88.Fn todr_attach
89function to register
90.Xr todr 9
91interface.
92.It Fa sc_year0
93The actual year represented by the clock's
94.Sq year
95counter.
96This is generally dependent on the system configuration in which
97the clock device is mounted.
98For instance, on Sun Microsystems machines
99the convention is to have clock's two-digit year represent the year 1968.
100.It Fa sc_flag
101This flag is used to specify machine-dependent features.
102.El
103.Pp
104Note that if the resulting date retrieved with the todr_gettime() method
105is earlier that January 1, 1970, the driver will assume that the chip's
106year counter actually represents a year in the 21st century.
107This behaviour can be overridden by setting the
108.Va INTERSIL7170_NO_CENT_ADJUST
109flag in
110.Fa sc_flag .
111.Sh SEE ALSO
112.Xr intro 4 ,
113.Xr todr 9
114.Sh HISTORY
115The
116.Nm
117driver first appeared in
118.Nx 1.5 .
119.Sh AUTHORS
120The
121.Nm
122driver was written by
123.An Paul Kranenburg
124.Aq pk@NetBSD.org .
125