1/*- 2 * Copyright (c) 2012 Marius Strobl <marius@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD$"); 29 30/* 31 * Driver for NXP PCF8563 real-time clock/calendar 32 */ 33 34#include <sys/param.h> 35#include <sys/systm.h> 36#include <sys/bus.h> 37#include <sys/clock.h> 38#include <sys/kernel.h> 39#include <sys/module.h> 40 41#include <dev/iicbus/iicbus.h> 42#include <dev/iicbus/iiconf.h> 43#include <dev/iicbus/pcf8563reg.h> 44 45#include "clock_if.h" 46#include "iicbus_if.h" 47 48#define PCF8563_NCLOCKREGS (PCF8563_R_YEAR - PCF8563_R_CS1 + 1) 49 50struct pcf8563_softc { 51 uint32_t sc_flags; 52#define PCF8563_CPOL (1 << 0) /* PCF8563_R_MONTH_C means 19xx */ 53 uint16_t sc_addr; /* PCF8563 slave address */ 54 uint16_t sc_year0; /* TOD clock year 0 */ 55}; 56 57static device_attach_t pcf8563_attach; 58static device_probe_t pcf8563_probe; 59static clock_gettime_t pcf8563_gettime; 60static clock_settime_t pcf8563_settime; 61 62static int 63pcf8563_probe(device_t dev) 64{ 65 66 device_set_desc(dev, "NXP PCF8563 RTC"); 67 return (BUS_PROBE_NOWILDCARD); 68} 69 70static int 71pcf8563_attach(device_t dev) 72{ 73 uint8_t reg = PCF8563_R_SECOND, val; 74 struct iic_msg msgs[] = { 75 { 0, IIC_M_WR, sizeof(reg), ® }, 76 { 0, IIC_M_RD, sizeof(val), &val } 77 }; 78 struct pcf8563_softc *sc; 79 int error; 80 81 sc = device_get_softc(dev); 82 sc->sc_addr = iicbus_get_addr(dev); 83 if (sc->sc_addr == 0) 84 sc->sc_addr = PCF8563_ADDR; 85 86 /* 87 * NB: PCF8563_R_SECOND_VL doesn't automatically clear when VDD 88 * rises above Vlow again and needs to be cleared manually. 89 * However, apparently this needs all of the time registers to be 90 * set, i.e. pcf8563_settime(), and not just PCF8563_R_SECOND in 91 * order for PCF8563_R_SECOND_VL to stick. Thus, we just issue a 92 * warning here rather than failing with ENXIO in case it is set. 93 * Note that pcf8563_settime() will also clear PCF8563_R_SECOND_VL 94 * as a side-effect. 95 */ 96 msgs[0].slave = msgs[1].slave = sc->sc_addr; 97 error = iicbus_transfer(device_get_parent(dev), msgs, sizeof(msgs) / 98 sizeof(*msgs)); 99 if (error != 0) { 100 device_printf(dev, "%s: cannot read RTC\n", __func__); 101 return (error); 102 } 103 if ((val & PCF8563_R_SECOND_VL) != 0) 104 device_printf(dev, "%s: battery low\n", __func__); 105 106 sc->sc_year0 = 1900; 107 clock_register(dev, 1000000); /* 1 second resolution */ 108 return (0); 109} 110 111static int 112pcf8563_gettime(device_t dev, struct timespec *ts) 113{ 114 struct clocktime ct; 115 uint8_t reg = PCF8563_R_SECOND, val[PCF8563_NCLOCKREGS]; 116 struct iic_msg msgs[] = { 117 { 0, IIC_M_WR, sizeof(reg), ® }, 118 { 0, IIC_M_RD, PCF8563_NCLOCKREGS, &val[PCF8563_R_SECOND] } 119 }; 120 struct pcf8563_softc *sc; 121 int error; 122 123 sc = device_get_softc(dev); 124 msgs[0].slave = msgs[1].slave = sc->sc_addr; 125 error = iicbus_transfer(device_get_parent(dev), msgs, sizeof(msgs) / 126 sizeof(*msgs)); 127 if (error != 0) { 128 device_printf(dev, "%s: cannot read RTC\n", __func__); 129 return (error); 130 } 131 132 ct.nsec = 0; 133 ct.sec = FROMBCD(val[PCF8563_R_SECOND] & PCF8563_M_SECOND); 134 ct.min = FROMBCD(val[PCF8563_R_MINUTE] & PCF8563_M_MINUTE); 135 ct.hour = FROMBCD(val[PCF8563_R_HOUR] & PCF8563_M_HOUR); 136 ct.day = FROMBCD(val[PCF8563_R_DAY] & PCF8563_M_DAY); 137 ct.dow = val[PCF8563_R_WEEKDAY] & PCF8563_M_WEEKDAY; 138 ct.mon = FROMBCD(val[PCF8563_R_MONTH] & PCF8563_M_MONTH); 139 ct.year = FROMBCD(val[PCF8563_R_YEAR] & PCF8563_M_YEAR); 140 ct.year += sc->sc_year0; 141 if (ct.year < POSIX_BASE_YEAR) 142 ct.year += 100; /* assume [1970, 2069] */ 143 if ((val[PCF8563_R_MONTH] & PCF8563_R_MONTH_C) != 0) { 144 if (ct.year >= 100 + sc->sc_year0) 145 sc->sc_flags |= PCF8563_CPOL; 146 } else if (ct.year < 100 + sc->sc_year0) 147 sc->sc_flags |= PCF8563_CPOL; 148 return (clock_ct_to_ts(&ct, ts)); 149} 150 151static int 152pcf8563_settime(device_t dev, struct timespec *ts) 153{ 154 struct clocktime ct; 155 uint8_t val[PCF8563_NCLOCKREGS]; 156 struct iic_msg msgs[] = { 157 { 0, IIC_M_WR, PCF8563_NCLOCKREGS - 1, &val[PCF8563_R_CS2] } 158 }; 159 struct pcf8563_softc *sc; 160 int error; 161 162 sc = device_get_softc(dev); 163 val[PCF8563_R_CS2] = PCF8563_R_SECOND; /* abuse */ 164 /* Accuracy is only one second. */ 165 if (ts->tv_nsec >= 500000000) 166 ts->tv_sec++; 167 ts->tv_nsec = 0; 168 clock_ts_to_ct(ts, &ct); 169 val[PCF8563_R_SECOND] = TOBCD(ct.sec); 170 val[PCF8563_R_MINUTE] = TOBCD(ct.min); 171 val[PCF8563_R_HOUR] = TOBCD(ct.hour); 172 val[PCF8563_R_DAY] = TOBCD(ct.day); 173 val[PCF8563_R_WEEKDAY] = ct.dow; 174 val[PCF8563_R_MONTH] = TOBCD(ct.mon); 175 val[PCF8563_R_YEAR] = TOBCD(ct.year % 100); 176 if ((sc->sc_flags & PCF8563_CPOL) != 0) { 177 if (ct.year >= 100 + sc->sc_year0) 178 val[PCF8563_R_MONTH] |= PCF8563_R_MONTH_C; 179 } else if (ct.year < 100 + sc->sc_year0) 180 val[PCF8563_R_MONTH] |= PCF8563_R_MONTH_C; 181 182 msgs[0].slave = sc->sc_addr; 183 error = iicbus_transfer(device_get_parent(dev), msgs, sizeof(msgs) / 184 sizeof(*msgs)); 185 if (error != 0) 186 device_printf(dev, "%s: cannot write RTC\n", __func__); 187 return (error); 188} 189 190static device_method_t pcf8563_methods[] = { 191 DEVMETHOD(device_probe, pcf8563_probe), 192 DEVMETHOD(device_attach, pcf8563_attach), 193 194 DEVMETHOD(clock_gettime, pcf8563_gettime), 195 DEVMETHOD(clock_settime, pcf8563_settime), 196 197 DEVMETHOD_END 198}; 199 200static driver_t pcf8563_driver = { 201 "pcf8563_rtc", 202 pcf8563_methods, 203 sizeof(struct pcf8563_softc), 204}; 205 206static devclass_t pcf8563_devclass; 207 208DRIVER_MODULE(pcf8563, iicbus, pcf8563_driver, pcf8563_devclass, NULL, NULL); 209MODULE_VERSION(pcf8563, 1); 210MODULE_DEPEND(pcf8563, iicbus, 1, 1, 1); 211