1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2020 Alstom Group. 5 * Copyright (c) 2020 Semihalf. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include <sys/param.h> 32 #include <sys/systm.h> 33 #include <sys/bus.h> 34 #include <sys/clock.h> 35 #include <sys/kernel.h> 36 #include <sys/lock.h> 37 #include <sys/module.h> 38 39 #include <dev/ofw/ofw_bus.h> 40 #include <dev/ofw/ofw_bus_subr.h> 41 42 #include <dev/iicbus/iiconf.h> 43 #include <dev/iicbus/iicbus.h> 44 45 #include "clock_if.h" 46 #include "iicbus_if.h" 47 48 #define BIT(x) (1 << (x)) 49 50 #define RX8803_TIME 0x0 51 #define RX8803_FLAGS 0xE 52 #define RX8803_CTRL 0xF 53 54 #define RX8803_FLAGS_V1F BIT(0) 55 #define RX8803_FLAGS_V2F BIT(1) 56 57 #define RX8803_CTRL_DISABLE BIT(0) 58 59 #define HALF_OF_SEC_NS 500000000 60 #define MAX_WRITE_LEN 16 61 62 struct rx8803_time { 63 uint8_t sec; 64 uint8_t min; 65 uint8_t hour; 66 uint8_t dow; 67 uint8_t day; 68 uint8_t mon; 69 uint8_t year; 70 }; 71 72 static int rx8803_probe(device_t dev); 73 static int rx8803_attach(device_t dev); 74 static int rx8803_detach(device_t dev); 75 76 static int rx8803_gettime(device_t dev, struct timespec *ts); 77 static int rx8803_settime(device_t dev, struct timespec *ts); 78 79 static int rx8803_check_status(device_t dev); 80 81 static int 82 rx8803_check_status(device_t dev) 83 { 84 uint8_t flags; 85 int rc; 86 87 rc = iicdev_readfrom(dev, RX8803_FLAGS, &flags, 1, IIC_WAIT); 88 if (rc != 0) 89 return (rc); 90 91 if (flags & RX8803_FLAGS_V2F) { 92 device_printf(dev, "Low voltage flag set, date is incorrect\n"); 93 return (ENXIO); 94 } 95 96 return (0); 97 } 98 99 static int 100 rx8803_gettime(device_t dev, struct timespec *ts) 101 { 102 struct rx8803_time data; 103 struct bcd_clocktime bcd; 104 int rc; 105 106 rc = rx8803_check_status(dev); 107 if (rc != 0) 108 return (rc); 109 110 rc = iicdev_readfrom(dev, 111 RX8803_TIME, 112 &data, sizeof(struct rx8803_time), 113 IIC_WAIT); 114 if (rc != 0) 115 return (rc); 116 117 bcd.nsec = 0; 118 bcd.sec = data.sec & 0x7F; 119 bcd.min = data.min & 0x7F; 120 bcd.hour = data.hour & 0x3F; 121 bcd.dow = flsl(data.dow & 0x7F) - 1; 122 bcd.day = data.day & 0x3F; 123 bcd.mon = (data.mon & 0x1F); 124 bcd.year = data.year; 125 126 clock_dbgprint_bcd(dev, CLOCK_DBG_READ, &bcd); 127 128 rc = clock_bcd_to_ts(&bcd, ts, false); 129 return (rc); 130 } 131 132 static int 133 rx8803_settime(device_t dev, struct timespec *ts) 134 { 135 struct rx8803_time data; 136 struct bcd_clocktime bcd; 137 uint8_t reg; 138 int rc; 139 140 ts->tv_sec -= utc_offset(); 141 clock_ts_to_bcd(ts, &bcd, false); 142 clock_dbgprint_bcd(dev, CLOCK_DBG_WRITE, &bcd); 143 144 data.sec = bcd.sec; 145 data.min = bcd.min; 146 data.hour = bcd.hour; 147 data.dow = 1 << bcd.dow; 148 data.day = bcd.day; 149 data.mon = bcd.mon; 150 data.year = bcd.year; 151 152 if (ts->tv_nsec > HALF_OF_SEC_NS) 153 data.sec++; 154 155 /* First disable clock. */ 156 rc = iicdev_readfrom(dev, RX8803_CTRL, ®, sizeof(uint8_t), IIC_WAIT); 157 if (rc != 0) 158 return (rc); 159 160 reg |= RX8803_CTRL_DISABLE; 161 162 rc = iicdev_writeto(dev, RX8803_CTRL, ®, sizeof(uint8_t), IIC_WAIT); 163 if (rc != 0) 164 return (rc); 165 166 /* Update the date. */ 167 rc = iicdev_writeto(dev, 168 RX8803_TIME, 169 &data, sizeof(struct rx8803_time), 170 IIC_WAIT); 171 if (rc != 0) 172 return (rc); 173 174 /* Now restart it. */ 175 reg &= ~RX8803_CTRL_DISABLE; 176 rc = iicdev_writeto(dev, RX8803_CTRL, ®, sizeof(uint8_t), IIC_WAIT); 177 if (rc != 0) 178 return (rc); 179 180 /* Clear low voltage flags, as we have just updated the clock. */ 181 rc = iicdev_readfrom(dev, RX8803_FLAGS, ®, sizeof(uint8_t), IIC_WAIT); 182 if (rc != 0) 183 return (rc); 184 185 reg &= ~(RX8803_FLAGS_V1F | RX8803_FLAGS_V2F); 186 rc = iicdev_writeto(dev, RX8803_FLAGS, ®, sizeof(uint8_t), IIC_WAIT); 187 return (rc); 188 } 189 190 static int 191 rx8803_probe(device_t dev) 192 { 193 194 if (!ofw_bus_is_compatible(dev, "epson,rx8803")) 195 return (ENXIO); 196 197 device_set_desc(dev, "Epson RX8803 Real Time Clock"); 198 199 return (BUS_PROBE_GENERIC); 200 } 201 202 static int 203 rx8803_attach(device_t dev) 204 { 205 206 /* Set 1 sec resolution. */ 207 clock_register_flags(dev, 1000000, 0); 208 clock_schedule(dev, 1); 209 210 return (0); 211 212 } 213 214 static int 215 rx8803_detach(device_t dev) 216 { 217 218 clock_unregister(dev); 219 220 return (0); 221 } 222 223 static device_method_t rx8803_methods[] = { 224 DEVMETHOD(device_probe, rx8803_probe), 225 DEVMETHOD(device_attach, rx8803_attach), 226 DEVMETHOD(device_detach, rx8803_detach), 227 228 DEVMETHOD(clock_gettime, rx8803_gettime), 229 DEVMETHOD(clock_settime, rx8803_settime), 230 231 DEVMETHOD_END, 232 }; 233 234 static driver_t rx8803_driver = { 235 "rx8803", 236 rx8803_methods, 237 0, /* We don't need softc for this one. */ 238 }; 239 240 DRIVER_MODULE(rx8803, iicbus, rx8803_driver, NULL, NULL); 241 MODULE_DEPEND(rx8803, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER); 242