1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2012 Yusuke Tanaka 5 * All rights reserved. 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, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 /*- 30 * Copyright (c) 2011 Frank Wille. 31 * All rights reserved. 32 * 33 * Written by Frank Wille for The NetBSD Project. 34 * 35 * Redistribution and use in source and binary forms, with or without 36 * modification, are permitted provided that the following conditions 37 * are met: 38 * 1. Redistributions of source code must retain the above copyright 39 * notice, this list of conditions and the following disclaimer. 40 * 2. Redistributions in binary form must reproduce the above copyright 41 * notice, this list of conditions and the following disclaimer in the 42 * documentation and/or other materials provided with the distribution. 43 * 44 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 45 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 46 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 47 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 48 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 49 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 50 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 51 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 52 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 53 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 54 * POSSIBILITY OF SUCH DAMAGE. 55 */ 56 57 #include <sys/cdefs.h> 58 /* 59 * Driver for Seiko Instruments S-35390A Real-time Clock 60 */ 61 62 #include "opt_platform.h" 63 64 #include <sys/param.h> 65 #include <sys/systm.h> 66 #include <sys/bus.h> 67 #include <sys/clock.h> 68 #include <sys/kernel.h> 69 #include <sys/module.h> 70 71 #include <dev/iicbus/iicbus.h> 72 #include <dev/iicbus/iiconf.h> 73 74 #ifdef FDT 75 #include <dev/ofw/openfirm.h> 76 #include <dev/ofw/ofw_bus.h> 77 #include <dev/ofw/ofw_bus_subr.h> 78 #endif 79 80 #include "clock_if.h" 81 #include "iicbus_if.h" 82 83 #define S390_DEVNAME "s35390a_rtc" 84 #define S390_DEVCODE 0x6 /* 0110 */ 85 /* 86 * S-35390A uses 4-bit device code + 3-bit command in the slave address 87 * field. The possible combination is 0x60-0x6f including the R/W bit. 88 * 0x60 means an write access to status register 1. 89 */ 90 #define S390_ADDR (S390_DEVCODE << 4) 91 92 /* Registers are encoded into the slave address */ 93 #define S390_STATUS1 (0 << 1) 94 #define S390_STATUS2 (1 << 1) 95 #define S390_REALTIME1 (2 << 1) 96 #define S390_REALTIME2 (3 << 1) 97 #define S390_INT1_1 (4 << 1) 98 #define S390_INT1_2 (5 << 1) 99 #define S390_CLOCKADJ (6 << 1) 100 #define S390_FREE (7 << 1) 101 102 /* Status1 bits */ 103 #define S390_ST1_POC (1 << 7) 104 #define S390_ST1_BLD (1 << 6) 105 #define S390_ST1_24H (1 << 1) 106 #define S390_ST1_RESET (1 << 0) 107 108 /* Status2 bits */ 109 #define S390_ST2_TEST (1 << 7) 110 111 /* Realtime1 data bytes */ 112 #define S390_RT1_NBYTES 7 113 #define S390_RT1_YEAR 0 114 #define S390_RT1_MONTH 1 115 #define S390_RT1_DAY 2 116 #define S390_RT1_WDAY 3 117 #define S390_RT1_HOUR 4 118 #define S390_RT1_MINUTE 5 119 #define S390_RT1_SECOND 6 120 121 struct s390rtc_softc { 122 device_t sc_dev; 123 uint16_t sc_addr; 124 }; 125 126 /* 127 * S-35390A interprets bits in each byte on SDA in reverse order. 128 * bitreverse() reverses the bits in uint8_t. 129 */ 130 static const uint8_t nibbletab[] = { 131 /* 0x0 0000 -> 0000 */ 0x0, 132 /* 0x1 0001 -> 1000 */ 0x8, 133 /* 0x2 0010 -> 0100 */ 0x4, 134 /* 0x3 0011 -> 1100 */ 0xc, 135 /* 0x4 0100 -> 0010 */ 0x2, 136 /* 0x5 0101 -> 1010 */ 0xa, 137 /* 0x6 0110 -> 0110 */ 0x6, 138 /* 0x7 0111 -> 1110 */ 0xe, 139 /* 0x8 1000 -> 0001 */ 0x1, 140 /* 0x9 1001 -> 1001 */ 0x9, 141 /* 0xa 1010 -> 0101 */ 0x5, 142 /* 0xb 1011 -> 1101 */ 0xd, 143 /* 0xc 1100 -> 0011 */ 0x3, 144 /* 0xd 1101 -> 1011 */ 0xb, 145 /* 0xe 1110 -> 0111 */ 0x7, 146 /* 0xf 1111 -> 1111 */ 0xf, }; 147 148 static uint8_t 149 bitreverse(uint8_t x) 150 { 151 152 return (nibbletab[x & 0xf] << 4) | nibbletab[x >> 4]; 153 } 154 155 static int 156 s390rtc_read(device_t dev, uint8_t reg, uint8_t *buf, size_t len) 157 { 158 struct s390rtc_softc *sc = device_get_softc(dev); 159 struct iic_msg msg[] = { 160 { 161 .slave = sc->sc_addr | reg, 162 .flags = IIC_M_RD, 163 .len = len, 164 .buf = buf, 165 }, 166 }; 167 int i; 168 int error; 169 170 error = iicbus_transfer_excl(dev, msg, 1, IIC_WAIT); 171 if (error) 172 return (error); 173 174 /* this chip returns each byte in reverse order */ 175 for (i = 0; i < len; ++i) 176 buf[i] = bitreverse(buf[i]); 177 178 return (0); 179 } 180 181 static int 182 s390rtc_write(device_t dev, uint8_t reg, uint8_t *buf, size_t len) 183 { 184 struct s390rtc_softc *sc = device_get_softc(dev); 185 struct iic_msg msg[] = { 186 { 187 .slave = sc->sc_addr | reg, 188 .flags = IIC_M_WR, 189 .len = len, 190 .buf = buf, 191 }, 192 }; 193 int i; 194 195 /* this chip expects each byte in reverse order */ 196 for (i = 0; i < len; ++i) 197 buf[i] = bitreverse(buf[i]); 198 199 return (iicbus_transfer_excl(dev, msg, 1, IIC_WAIT)); 200 } 201 202 static int 203 s390rtc_probe(device_t dev) 204 { 205 206 #ifdef FDT 207 if (!ofw_bus_status_okay(dev)) 208 return (ENXIO); 209 210 if (!ofw_bus_is_compatible(dev, "sii,s35390a")) 211 return (ENXIO); 212 #else 213 if (iicbus_get_addr(dev) != S390_ADDR) { 214 if (bootverbose) 215 device_printf(dev, "slave address mismatch. " 216 "(%02x != %02x)\n", iicbus_get_addr(dev), 217 S390_ADDR); 218 return (ENXIO); 219 } 220 #endif 221 device_set_desc(dev, "Seiko Instruments S-35390A RTC"); 222 223 return (BUS_PROBE_DEFAULT); 224 } 225 226 static void 227 s390rtc_start(void *arg) 228 { 229 device_t dev; 230 uint8_t reg; 231 int error; 232 233 dev = arg; 234 235 /* Reset the chip and turn on 24h mode, after power-off or battery. */ 236 error = s390rtc_read(dev, S390_STATUS1, ®, 1); 237 if (error) { 238 device_printf(dev, "%s: cannot read status1 register\n", 239 __func__); 240 return; 241 } 242 if (reg & (S390_ST1_POC | S390_ST1_BLD)) { 243 reg |= S390_ST1_24H | S390_ST1_RESET; 244 error = s390rtc_write(dev, S390_STATUS1, ®, 1); 245 if (error) { 246 device_printf(dev, 247 "%s: cannot initialize\n", __func__); 248 return; 249 } 250 } 251 252 /* Disable the test mode, when enabled. */ 253 error = s390rtc_read(dev, S390_STATUS2, ®, 1); 254 if (error) { 255 device_printf(dev, "%s: cannot read status2 register\n", 256 __func__); 257 return; 258 } 259 if (reg & S390_ST2_TEST) { 260 reg &= ~S390_ST2_TEST; 261 error = s390rtc_write(dev, S390_STATUS2, ®, 1); 262 if (error) { 263 device_printf(dev, 264 "%s: cannot disable the test mode\n", __func__); 265 return; 266 } 267 } 268 269 clock_register(dev, 1000000); /* 1 second resolution */ 270 } 271 272 static int 273 s390rtc_attach(device_t dev) 274 { 275 struct s390rtc_softc *sc; 276 277 sc = device_get_softc(dev); 278 sc->sc_dev = dev; 279 sc->sc_addr = iicbus_get_addr(dev); 280 281 config_intrhook_oneshot(s390rtc_start, dev); 282 283 return (0); 284 } 285 286 static int 287 s390rtc_detach(device_t dev) 288 { 289 290 clock_unregister(dev); 291 return (0); 292 } 293 294 static int 295 s390rtc_gettime(device_t dev, struct timespec *ts) 296 { 297 uint8_t bcd[S390_RT1_NBYTES]; 298 struct bcd_clocktime bct; 299 int error; 300 301 error = s390rtc_read(dev, S390_REALTIME1, bcd, S390_RT1_NBYTES); 302 if (error) { 303 device_printf(dev, "%s: cannot read realtime1 register\n", 304 __func__); 305 return (error); 306 } 307 308 /* 309 * Convert the register values into something useable. 310 */ 311 bct.nsec = 0; 312 bct.sec = bcd[S390_RT1_SECOND]; 313 bct.min = bcd[S390_RT1_MINUTE]; 314 bct.hour = bcd[S390_RT1_HOUR] & 0x3f; 315 bct.day = bcd[S390_RT1_DAY]; 316 bct.dow = bcd[S390_RT1_WDAY] & 0x07; 317 bct.mon = bcd[S390_RT1_MONTH]; 318 bct.year = bcd[S390_RT1_YEAR]; 319 320 clock_dbgprint_bcd(dev, CLOCK_DBG_READ, &bct); 321 return (clock_bcd_to_ts(&bct, ts, false)); 322 } 323 324 static int 325 s390rtc_settime(device_t dev, struct timespec *ts) 326 { 327 uint8_t bcd[S390_RT1_NBYTES]; 328 struct bcd_clocktime bct; 329 330 clock_ts_to_bcd(ts, &bct, false); 331 clock_dbgprint_bcd(dev, CLOCK_DBG_WRITE, &bct); 332 333 /* 334 * Convert our time representation into something the S-xx390 335 * can understand. 336 */ 337 bcd[S390_RT1_SECOND] = bct.sec; 338 bcd[S390_RT1_MINUTE] = bct.min; 339 bcd[S390_RT1_HOUR] = bct.hour; 340 bcd[S390_RT1_DAY] = bct.day; 341 bcd[S390_RT1_WDAY] = bct.dow; 342 bcd[S390_RT1_MONTH] = bct.mon; 343 bcd[S390_RT1_YEAR] = bct.year & 0xff; 344 345 return (s390rtc_write(dev, S390_REALTIME1, bcd, S390_RT1_NBYTES)); 346 } 347 348 static device_method_t s390rtc_methods[] = { 349 DEVMETHOD(device_probe, s390rtc_probe), 350 DEVMETHOD(device_attach, s390rtc_attach), 351 DEVMETHOD(device_detach, s390rtc_detach), 352 353 DEVMETHOD(clock_gettime, s390rtc_gettime), 354 DEVMETHOD(clock_settime, s390rtc_settime), 355 356 DEVMETHOD_END 357 }; 358 359 static driver_t s390rtc_driver = { 360 S390_DEVNAME, 361 s390rtc_methods, 362 sizeof(struct s390rtc_softc), 363 }; 364 365 DRIVER_MODULE(s35390a, iicbus, s390rtc_driver, NULL, NULL); 366 MODULE_VERSION(s35390a, 1); 367 MODULE_DEPEND(s35390a, iicbus, 1, 1, 1); 368