1.\" $NetBSD: todr.9,v 1.6 2003/04/16 13:35:34 wiz Exp $ 2.\" 3.\" Copyright (c) 2000 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Paul Kranenburg. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the NetBSD 20.\" Foundation, Inc. and its contributors. 21.\" 4. Neither the name of The NetBSD Foundation nor the names of its 22.\" contributors may be used to endorse or promote products derived 23.\" from this software without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 29.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35.\" POSSIBILITY OF SUCH DAMAGE. 36.\" 37.Dd July 22, 2000 38.Dt TODR 9 39.Os 40.Sh NAME 41.Nm todr_gettime 42.Nm todr_settime 43.Nm todr_getcal 44.Nm todr_setcal 45.Nm clock_ymdhms_to_secs 46.Nm clock_secs_to_ymdhms 47.Nd time-of-day clock support 48.Sh SYNOPSIS 49.In dev/clock_subr.h 50.Ft int 51.Fn todr_gettime "todr_chip_handle_t" "struct timeval *" 52.Ft int 53.Fn todr_settime "todr_chip_handle_t" "struct timeval *" 54.Ft int 55.Fn todr_getcal "todr_chip_handle_t" "int *" 56.Ft int 57.Fn todr_setcal "todr_chip_handle_t" "int" 58.Ft void 59.Fn clock_secs_to_ymdhms "int" "struct clock_ymdhms *" 60.Ft time_t 61.Fn clock_ymdhms_to_secs "struct clock_ymdhms *" 62.Sh DESCRIPTION 63The 64.Fn todr_* 65functions provide an interface to read, set and control 66.Ql time-of-day 67devices. 68The 69.Fa todr_chip_handle_t 70should be obtained from a driver for a particular hardware device that 71implements this interface. 72Examples of such drivers currently include 73.Xr mk48txx 4 74and 75.Xr intersil7170 4 . 76.Pp 77The 78.Fn todr_gettime 79retrieves the current data and time from the TODR device and returns it 80in the 81.Fa struct timeval 82storage provided by the caller. 83.Fn todr_settime 84sets the date and time in the TODR device represented by 85.Fa todr_chip_handle_t 86according to the 87.Fa struct timeval 88argument. 89.Pp 90.Fn todr_setcal 91specifies a calibration value in PPM units to be programmed in the TODR 92device. 93Positive values shall speed up the TODR clock, negative values 94shall slow it down. 95If the device in not capable of handling calibration, 96this function shall return 97.Va EOPNOTSUPP . 98The measurement and calculations necessary to use this method is 99expected to be provided by higher-level software modules. 100.Fn todr_getcal 101returns the current calibration (in PPM units) in effect on the TODR device. 102.Pp 103The utilities 104.Fn clock_secs_to_ymdhms 105and 106.Fn clock_ymdhms_to_secs 107are provided to convert a time value in seconds to and from a structure 108representing the date and time as a 109.Aq year,month,day,weekday,hour,minute,seconds 110tuple. 111This structure is defined as follows: 112.Bd -literal 113struct clock_ymdhms { 114 u_short dt_year; /* Year */ 115 u_char dt_mon; /* Month (1-12) */ 116 u_char dt_day; /* Day (0-365) */ 117 u_char dt_wday; /* Day of week (0-6) */ 118 u_char dt_hour; /* Hour (0-23) */ 119 u_char dt_min; /* Minute (0-59) */ 120 u_char dt_sec; /* Second (0-59) */ 121}; 122.Ed 123.Pp 124Note: leap years are recognised by these conversion routines. 125.Sh RETURN VALUES 126The 127.Fn todr_* 128functions return 0 if the requested operation was successful; 129otherwise an error code from 130.Aq Pa sys/errno.h 131shall be returned. 132However, behaviour is undefined if an invalid 133.Fa todr_chip_handle_t 134is passed to any of these functions. 135The 136.Fn clock_secs_to_ymdhms 137and 138.Fn clock_ymdhms_to_secs 139functions never fail. 140.Sh SEE ALSO 141.Xr inittodr 9 , 142.Xr resettodr 9 , 143.Xr time 9 144