1/*- 2 * Copyright (c) 2006 Sam Leffler. 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 ``AS IS'' AND ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23 */ 24 25#include <sys/cdefs.h> 26__FBSDID("$FreeBSD$"); 27/* 28 * Dallas Semiconductor DS1672 RTC sitting on the I2C bus. 29 */ 30#include <sys/param.h> 31#include <sys/systm.h> 32#include <sys/kernel.h> 33#include <sys/module.h> 34#include <sys/clock.h> 35#include <sys/time.h> 36#include <sys/bus.h> 37#include <sys/resource.h> 38#include <sys/rman.h> 39 40#include <dev/iicbus/iiconf.h> 41 42#include "iicbus_if.h" 43#include "clock_if.h" 44 45#define IIC_M_WR 0 /* write operation */ 46 47#define DS1672_ADDR 0xd0 /* slave address */ 48 49#define DS1672_COUNTER 0 /* counter (bytes 0-3) */ 50#define DS1672_CTRL 4 /* control (1 byte) */ 51#define DS1672_TRICKLE 5 /* trickle charger (1 byte) */ 52 53#define DS1672_CTRL_EOSC (1 << 7) /* Stop/start flag. */ 54 55#define NANOSEC 1000000000 56 57#define MAX_IIC_DATA_SIZE 4 58 59struct ds1672_softc { 60 device_t sc_dev; 61}; 62 63static int 64ds1672_probe(device_t dev) 65{ 66 /* XXX really probe? */ 67 device_set_desc(dev, "Dallas Semiconductor DS1672 RTC"); 68 return (BUS_PROBE_NOWILDCARD); 69} 70 71static int 72ds1672_read(device_t dev, uint8_t addr, uint8_t *data, uint8_t size) 73{ 74 struct iic_msg msgs[2] = { 75 { DS1672_ADDR, IIC_M_WR, 1, &addr }, 76 { DS1672_ADDR, IIC_M_RD, size, data } 77 }; 78 79 return (iicbus_transfer(dev, msgs, 2)); 80} 81 82static int 83ds1672_write(device_t dev, uint8_t addr, uint8_t *data, uint8_t size) 84{ 85 uint8_t buffer[MAX_IIC_DATA_SIZE + 1]; 86 struct iic_msg msgs[1] = { 87 { DS1672_ADDR, IIC_M_WR, size + 1, buffer }, 88 }; 89 90 if (size > MAX_IIC_DATA_SIZE) 91 return (ENOMEM); 92 /* NB: register pointer precedes actual data */ 93 buffer[0] = addr; 94 memcpy(buffer + 1, data, size); 95 return (iicbus_transfer(dev, msgs, 1)); 96} 97 98static int 99ds1672_init(device_t dev) 100{ 101 uint8_t ctrl; 102 int error; 103 104 error = ds1672_read(dev, DS1672_CTRL, &ctrl, 1); 105 if (error) 106 return (error); 107 108 /* 109 * Check if oscialltor is not runned. 110 */ 111 if (ctrl & DS1672_CTRL_EOSC) { 112 device_printf(dev, "RTC oscillator was stopped. Check system" 113 " time and RTC battery.\n"); 114 ctrl &= ~DS1672_CTRL_EOSC; /* Start oscillator. */ 115 error = ds1672_write(dev, DS1672_CTRL, &ctrl, 1); 116 } 117 return (error); 118} 119 120static int 121ds1672_attach(device_t dev) 122{ 123 struct ds1672_softc *sc = device_get_softc(dev); 124 int error; 125 126 sc->sc_dev = dev; 127 error = ds1672_init(dev); 128 if (error) 129 return (error); 130 clock_register(dev, 1000); 131 return (0); 132} 133 134static int 135ds1672_gettime(device_t dev, struct timespec *ts) 136{ 137 uint8_t secs[4]; 138 int error; 139 140 error = ds1672_read(dev, DS1672_COUNTER, secs, 4); 141 if (error == 0) { 142 /* counter has seconds since epoch */ 143 ts->tv_sec = (secs[3] << 24) | (secs[2] << 16) 144 | (secs[1] << 8) | (secs[0] << 0); 145 ts->tv_nsec = NANOSEC / 2; 146 } 147 return (error); 148} 149 150static int 151ds1672_settime(device_t dev, struct timespec *ts) 152{ 153 uint8_t data[4]; 154 155 data[0] = (ts->tv_sec >> 0) & 0xff; 156 data[1] = (ts->tv_sec >> 8) & 0xff; 157 data[2] = (ts->tv_sec >> 16) & 0xff; 158 data[3] = (ts->tv_sec >> 24) & 0xff; 159 160 return (ds1672_write(dev, DS1672_COUNTER, data, 4)); 161} 162 163static device_method_t ds1672_methods[] = { 164 DEVMETHOD(device_probe, ds1672_probe), 165 DEVMETHOD(device_attach, ds1672_attach), 166 167 DEVMETHOD(clock_gettime, ds1672_gettime), 168 DEVMETHOD(clock_settime, ds1672_settime), 169 170 DEVMETHOD_END 171}; 172 173static driver_t ds1672_driver = { 174 "ds1672_rtc", 175 ds1672_methods, 176 sizeof(struct ds1672_softc), 177}; 178static devclass_t ds1672_devclass; 179 180DRIVER_MODULE(ds1672, iicbus, ds1672_driver, ds1672_devclass, 0, 0); 181MODULE_VERSION(ds1672, 1); 182MODULE_DEPEND(ds1672, iicbus, 1, 1, 1); 183