1 /*- 2 * Copyright (c) 2015 Luiz Otavio O Souza <loos@FreeBSD.org> 3 * Copyright (c) 2022 Mathew McBride <matt@traverse.com.au> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 /* 30 * Driver for Maxim DS1307 I2C real-time clock/calendar. 31 */ 32 33 #include "opt_platform.h" 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/bus.h> 38 #include <sys/clock.h> 39 #include <sys/kernel.h> 40 #include <sys/module.h> 41 #include <sys/sysctl.h> 42 43 #include <dev/iicbus/iicbus.h> 44 #include <dev/iicbus/iiconf.h> 45 #ifdef FDT 46 #include <dev/ofw/openfirm.h> 47 #include <dev/ofw/ofw_bus.h> 48 #include <dev/ofw/ofw_bus_subr.h> 49 #endif 50 51 #include <dev/iicbus/rtc/ds1307reg.h> 52 53 #include "clock_if.h" 54 #include "iicbus_if.h" 55 56 enum { 57 TYPE_DS1307, 58 TYPE_MAXIM1307, 59 TYPE_MICROCHIP_MCP7491X, 60 TYPE_EPSON_RX8035, 61 TYPE_COUNT 62 }; 63 64 struct ds1307_softc { 65 device_t sc_dev; 66 struct intr_config_hook enum_hook; 67 uint32_t chiptype; 68 uint8_t sc_ctrl; 69 bool sc_use_ampm; 70 }; 71 72 static void ds1307_start(void *); 73 74 #ifdef FDT 75 static const struct ofw_compat_data ds1307_compat_data[] = { 76 {"dallas,ds1307", TYPE_DS1307}, 77 {"maxim,ds1307", TYPE_MAXIM1307}, 78 {"microchip,mcp7941x", TYPE_MICROCHIP_MCP7491X}, 79 {"epson,rx8035", TYPE_EPSON_RX8035}, 80 { NULL, 0 } 81 }; 82 #endif 83 84 static int 85 ds1307_read1(device_t dev, uint8_t reg, uint8_t *data) 86 { 87 88 return (iicdev_readfrom(dev, reg, data, 1, IIC_INTRWAIT)); 89 } 90 91 static int 92 ds1307_write1(device_t dev, uint8_t reg, uint8_t data) 93 { 94 95 return (iicdev_writeto(dev, reg, &data, 1, IIC_INTRWAIT)); 96 } 97 98 static int 99 ds1307_ctrl_read(struct ds1307_softc *sc) 100 { 101 int error; 102 103 sc->sc_ctrl = 0; 104 error = ds1307_read1(sc->sc_dev, DS1307_CONTROL, &sc->sc_ctrl); 105 if (error) { 106 device_printf(sc->sc_dev, "%s: cannot read from RTC: %d\n", 107 __func__, error); 108 return (error); 109 } 110 111 return (0); 112 } 113 114 static int 115 ds1307_ctrl_write(struct ds1307_softc *sc) 116 { 117 int error; 118 uint8_t ctrl; 119 120 ctrl = sc->sc_ctrl & DS1307_CTRL_MASK; 121 error = ds1307_write1(sc->sc_dev, DS1307_CONTROL, ctrl); 122 if (error != 0) 123 device_printf(sc->sc_dev, "%s: cannot write to RTC: %d\n", 124 __func__, error); 125 126 return (error); 127 } 128 129 static int 130 ds1307_sqwe_sysctl(SYSCTL_HANDLER_ARGS) 131 { 132 int sqwe, error, newv, sqwe_bit; 133 struct ds1307_softc *sc; 134 135 sc = (struct ds1307_softc *)arg1; 136 error = ds1307_ctrl_read(sc); 137 if (error != 0) 138 return (error); 139 if (sc->chiptype == TYPE_MICROCHIP_MCP7491X) 140 sqwe_bit = MCP7941X_CTRL_SQWE; 141 else 142 sqwe_bit = DS1307_CTRL_SQWE; 143 sqwe = newv = (sc->sc_ctrl & sqwe_bit) ? 1 : 0; 144 error = sysctl_handle_int(oidp, &newv, 0, req); 145 if (error != 0 || req->newptr == NULL) 146 return (error); 147 if (sqwe != newv) { 148 sc->sc_ctrl &= ~sqwe_bit; 149 if (newv) 150 sc->sc_ctrl |= sqwe_bit; 151 error = ds1307_ctrl_write(sc); 152 if (error != 0) 153 return (error); 154 } 155 156 return (error); 157 } 158 159 static int 160 ds1307_sqw_freq_sysctl(SYSCTL_HANDLER_ARGS) 161 { 162 int ds1307_sqw_freq[] = { 1, 4096, 8192, 32768 }; 163 int error, freq, i, newf, tmp; 164 struct ds1307_softc *sc; 165 166 sc = (struct ds1307_softc *)arg1; 167 error = ds1307_ctrl_read(sc); 168 if (error != 0) 169 return (error); 170 tmp = (sc->sc_ctrl & DS1307_CTRL_RS_MASK); 171 if (tmp >= nitems(ds1307_sqw_freq)) 172 tmp = nitems(ds1307_sqw_freq) - 1; 173 freq = ds1307_sqw_freq[tmp]; 174 error = sysctl_handle_int(oidp, &freq, 0, req); 175 if (error != 0 || req->newptr == NULL) 176 return (error); 177 if (freq != ds1307_sqw_freq[tmp]) { 178 newf = 0; 179 for (i = 0; i < nitems(ds1307_sqw_freq); i++) 180 if (freq >= ds1307_sqw_freq[i]) 181 newf = i; 182 sc->sc_ctrl &= ~DS1307_CTRL_RS_MASK; 183 sc->sc_ctrl |= newf; 184 error = ds1307_ctrl_write(sc); 185 if (error != 0) 186 return (error); 187 } 188 189 return (error); 190 } 191 192 static int 193 ds1307_sqw_out_sysctl(SYSCTL_HANDLER_ARGS) 194 { 195 int sqwe, error, newv; 196 struct ds1307_softc *sc; 197 198 sc = (struct ds1307_softc *)arg1; 199 error = ds1307_ctrl_read(sc); 200 if (error != 0) 201 return (error); 202 sqwe = newv = (sc->sc_ctrl & DS1307_CTRL_OUT) ? 1 : 0; 203 error = sysctl_handle_int(oidp, &newv, 0, req); 204 if (error != 0 || req->newptr == NULL) 205 return (error); 206 if (sqwe != newv) { 207 sc->sc_ctrl &= ~DS1307_CTRL_OUT; 208 if (newv) 209 sc->sc_ctrl |= DS1307_CTRL_OUT; 210 error = ds1307_ctrl_write(sc); 211 if (error != 0) 212 return (error); 213 } 214 215 return (error); 216 } 217 218 static int 219 ds1307_probe(device_t dev) 220 { 221 #ifdef FDT 222 const struct ofw_compat_data *compat; 223 224 if (!ofw_bus_status_okay(dev)) 225 return (ENXIO); 226 227 compat = ofw_bus_search_compatible(dev, ds1307_compat_data); 228 if (compat->ocd_str == NULL) 229 return (ENXIO); 230 231 switch(compat->ocd_data) { 232 case TYPE_DS1307: 233 device_set_desc(dev, "Dallas DS1307"); 234 break; 235 case TYPE_MAXIM1307: 236 device_set_desc(dev, "Maxim DS1307"); 237 break; 238 case TYPE_MICROCHIP_MCP7491X: 239 device_set_desc(dev, "Microchip MCP7491X"); 240 break; 241 case TYPE_EPSON_RX8035: 242 device_set_desc(dev, "Epson RX-8035"); 243 break; 244 default: 245 device_set_desc(dev, "Unknown DS1307-like device"); 246 break; 247 } 248 return (BUS_PROBE_DEFAULT); 249 #endif 250 251 device_set_desc(dev, "Maxim DS1307 RTC"); 252 return (BUS_PROBE_NOWILDCARD); 253 } 254 255 static int 256 ds1307_attach(device_t dev) 257 { 258 #ifdef FDT 259 const struct ofw_compat_data *compat; 260 #endif 261 struct ds1307_softc *sc; 262 263 sc = device_get_softc(dev); 264 sc->sc_dev = dev; 265 sc->enum_hook.ich_func = ds1307_start; 266 sc->enum_hook.ich_arg = dev; 267 #ifdef FDT 268 compat = ofw_bus_search_compatible(dev, ds1307_compat_data); 269 sc->chiptype = compat->ocd_data; 270 /* Unify the chiptypes to DS1307 where possible. */ 271 if (sc->chiptype == TYPE_MAXIM1307) 272 sc->chiptype = TYPE_DS1307; 273 #else 274 sc->chiptype = TYPE_DS1307; 275 #endif 276 277 /* 278 * We have to wait until interrupts are enabled. Usually I2C read 279 * and write only works when the interrupts are available. 280 */ 281 if (config_intrhook_establish(&sc->enum_hook) != 0) 282 return (ENOMEM); 283 284 return (0); 285 } 286 287 static int 288 ds1307_detach(device_t dev) 289 { 290 291 clock_unregister(dev); 292 return (0); 293 } 294 295 static bool 296 is_epson_time_valid(struct ds1307_softc *sc) 297 { 298 device_t dev; 299 int error; 300 uint8_t ctrl2; 301 302 dev = sc->sc_dev; 303 304 /* 305 * The RX-8035 single register read is non-standard 306 * Refer to section 8.9.5 of the RX-8035 application manual: 307 * "I2C bus basic transfer format", under "Standard Read Method". 308 * Basically, register to read goes into the top 4 bits. 309 */ 310 error = ds1307_read1(dev, (RX8035_CTRL_2 << 4), &ctrl2); 311 if (error) { 312 device_printf(dev, "%s cannot read Control 2 register: %d\n", 313 __func__, error); 314 return (false); 315 } 316 317 if (ctrl2 & RX8035_CTRL_2_XSTP) { 318 device_printf(dev, "Oscillation stop detected (ctrl2=%#02x)\n", 319 ctrl2); 320 return (false); 321 } 322 323 /* 324 * Power on reset (PON) generally implies oscillation stop, 325 * but catch it as well to be sure. 326 */ 327 if (ctrl2 & RX8035_CTRL_2_PON) { 328 device_printf(dev, "Power-on reset detected (ctrl2=%#02x)\n", 329 ctrl2); 330 return (false); 331 } 332 333 return (true); 334 } 335 336 static int 337 mark_epson_time_valid(struct ds1307_softc *sc) 338 { 339 device_t dev; 340 int error; 341 uint8_t ctrl2; 342 uint8_t control_mask; 343 344 dev = sc->sc_dev; 345 346 error = ds1307_read1(dev, (RX8035_CTRL_2 << 4), &ctrl2); 347 if (error) { 348 device_printf(dev, "%s cannot read Control 2 register: %d\n", 349 __func__, error); 350 return (false); 351 } 352 353 control_mask = (RX8035_CTRL_2_PON | RX8035_CTRL_2_XSTP | RX8035_CTRL_2_VDET); 354 ctrl2 = ctrl2 & ~(control_mask); 355 356 error = ds1307_write1(dev, (RX8035_CTRL_2 << 4), ctrl2); 357 if (error) { 358 device_printf(dev, "%s cannot write to Control 2 register: %d\n", 359 __func__, error); 360 return (false); 361 } 362 return (true); 363 } 364 365 static bool is_dev_time_valid(struct ds1307_softc *sc) 366 { 367 device_t dev; 368 int error; 369 uint8_t osc_en; 370 uint8_t secs; 371 372 /* Epson RTCs have different control/status registers. */ 373 if (sc->chiptype == TYPE_EPSON_RX8035) 374 return (is_epson_time_valid(sc)); 375 376 dev = sc->sc_dev; 377 /* Check if the oscillator is disabled. */ 378 error = ds1307_read1(dev, DS1307_SECS, &secs); 379 if (error) { 380 device_printf(dev, "%s: cannot read from RTC: %d\n", 381 __func__, error); 382 return (false); 383 } 384 385 switch (sc->chiptype) { 386 case TYPE_MICROCHIP_MCP7491X: 387 osc_en = 0x80; 388 break; 389 default: 390 osc_en = 0x00; 391 break; 392 } 393 if (((secs & DS1307_SECS_CH) ^ osc_en) != 0) 394 return (false); 395 396 return (true); 397 } 398 399 static void 400 ds1307_start(void *xdev) 401 { 402 device_t dev; 403 struct ds1307_softc *sc; 404 struct sysctl_ctx_list *ctx; 405 struct sysctl_oid *tree_node; 406 struct sysctl_oid_list *tree; 407 408 dev = (device_t)xdev; 409 sc = device_get_softc(dev); 410 411 config_intrhook_disestablish(&sc->enum_hook); 412 413 if (!is_dev_time_valid(sc)) 414 device_printf(dev, 415 "WARNING: RTC clock stopped, check the battery.\n"); 416 417 /* 418 * Configuration parameters: 419 * square wave output cannot be changed or inhibited on the RX-8035, 420 * so don't present the sysctls there. 421 */ 422 if (sc->chiptype == TYPE_EPSON_RX8035) 423 goto skip_sysctl; 424 425 ctx = device_get_sysctl_ctx(dev); 426 tree_node = device_get_sysctl_tree(dev); 427 tree = SYSCTL_CHILDREN(tree_node); 428 429 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "sqwe", 430 CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_MPSAFE, sc, 0, 431 ds1307_sqwe_sysctl, "IU", "DS1307 square-wave enable"); 432 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "sqw_freq", 433 CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_MPSAFE, sc, 0, 434 ds1307_sqw_freq_sysctl, "IU", 435 "DS1307 square-wave output frequency"); 436 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "sqw_out", 437 CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_MPSAFE, sc, 0, 438 ds1307_sqw_out_sysctl, "IU", "DS1307 square-wave output state"); 439 skip_sysctl: 440 441 /* 442 * Register as a clock with 1 second resolution. Schedule the 443 * clock_settime() method to be called just after top-of-second; 444 * resetting the time resets top-of-second in the hardware. 445 */ 446 clock_register_flags(dev, 1000000, CLOCKF_SETTIME_NO_ADJ); 447 clock_schedule(dev, 1); 448 } 449 450 static int 451 ds1307_gettime(device_t dev, struct timespec *ts) 452 { 453 struct bcd_clocktime bct; 454 struct ds1307_softc *sc; 455 int error; 456 uint8_t data[7], hourmask, ampm_mode; 457 458 sc = device_get_softc(dev); 459 error = iicdev_readfrom(sc->sc_dev, DS1307_SECS, data, sizeof(data), 460 IIC_INTRWAIT); 461 if (error != 0) { 462 device_printf(dev, "%s: cannot read from RTC: %d\n", 463 __func__, error); 464 return (error); 465 } 466 467 if (!is_dev_time_valid(sc)) { 468 device_printf(dev, "Device time not valid.\n"); 469 return (EINVAL); 470 } 471 472 /* 473 * If the chip is in AM/PM mode remember that. 474 * The EPSON uses a 1 to signify 24 hour mode, while the DS uses a 0, 475 * in slighly different positions. 476 */ 477 if (sc->chiptype == TYPE_EPSON_RX8035) 478 ampm_mode = !(data[DS1307_HOUR] & RX8035_HOUR_USE_24); 479 else 480 ampm_mode = data[DS1307_HOUR] & DS1307_HOUR_USE_AMPM; 481 482 if (ampm_mode) { 483 sc->sc_use_ampm = true; 484 hourmask = DS1307_HOUR_MASK_12HR; 485 } else 486 hourmask = DS1307_HOUR_MASK_24HR; 487 488 bct.nsec = 0; 489 bct.ispm = (data[DS1307_HOUR] & DS1307_HOUR_IS_PM) != 0; 490 bct.sec = data[DS1307_SECS] & DS1307_SECS_MASK; 491 bct.min = data[DS1307_MINS] & DS1307_MINS_MASK; 492 bct.hour = data[DS1307_HOUR] & hourmask; 493 bct.day = data[DS1307_DATE] & DS1307_DATE_MASK; 494 bct.mon = data[DS1307_MONTH] & DS1307_MONTH_MASK; 495 bct.year = data[DS1307_YEAR] & DS1307_YEAR_MASK; 496 497 clock_dbgprint_bcd(sc->sc_dev, CLOCK_DBG_READ, &bct); 498 return (clock_bcd_to_ts(&bct, ts, sc->sc_use_ampm)); 499 } 500 501 static int 502 ds1307_settime(device_t dev, struct timespec *ts) 503 { 504 struct bcd_clocktime bct; 505 struct ds1307_softc *sc; 506 int error, year; 507 uint8_t data[7]; 508 uint8_t pmflags; 509 510 sc = device_get_softc(dev); 511 512 /* 513 * We request a timespec with no resolution-adjustment. That also 514 * disables utc adjustment, so apply that ourselves. 515 */ 516 ts->tv_sec -= utc_offset(); 517 clock_ts_to_bcd(ts, &bct, sc->sc_use_ampm); 518 clock_dbgprint_bcd(sc->sc_dev, CLOCK_DBG_WRITE, &bct); 519 520 /* 521 * If the chip is in AM/PM mode, adjust hour and set flags as needed. 522 * The AM/PM bit polarity and position is different on the EPSON. 523 */ 524 if (sc->sc_use_ampm) { 525 pmflags = (sc->chiptype != TYPE_EPSON_RX8035) ? 526 DS1307_HOUR_USE_AMPM : 0; 527 if (bct.ispm) 528 pmflags |= DS1307_HOUR_IS_PM; 529 530 } else if (sc->chiptype == TYPE_EPSON_RX8035) 531 pmflags = RX8035_HOUR_USE_24; 532 else 533 pmflags = 0; 534 535 data[DS1307_SECS] = bct.sec; 536 data[DS1307_MINS] = bct.min; 537 data[DS1307_HOUR] = bct.hour | pmflags; 538 data[DS1307_DATE] = bct.day; 539 data[DS1307_WEEKDAY] = bct.dow; 540 data[DS1307_MONTH] = bct.mon; 541 data[DS1307_YEAR] = bct.year & 0xff; 542 if (sc->chiptype == TYPE_MICROCHIP_MCP7491X) { 543 data[DS1307_SECS] |= MCP7941X_SECS_ST; 544 data[DS1307_WEEKDAY] |= MCP7941X_WEEKDAY_VBATEN; 545 year = bcd2bin(bct.year >> 8) * 100 + bcd2bin(bct.year & 0xff); 546 if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0) 547 data[DS1307_MONTH] |= MCP7941X_MONTH_LPYR; 548 } 549 550 /* Write the time back to RTC. */ 551 error = iicdev_writeto(sc->sc_dev, DS1307_SECS, data, sizeof(data), 552 IIC_INTRWAIT); 553 if (error != 0) 554 device_printf(dev, "%s: cannot write to RTC: %d\n", 555 __func__, error); 556 557 if (sc->chiptype == TYPE_EPSON_RX8035) 558 error = mark_epson_time_valid(sc); 559 560 return (error); 561 } 562 563 static device_method_t ds1307_methods[] = { 564 DEVMETHOD(device_probe, ds1307_probe), 565 DEVMETHOD(device_attach, ds1307_attach), 566 DEVMETHOD(device_detach, ds1307_detach), 567 568 DEVMETHOD(clock_gettime, ds1307_gettime), 569 DEVMETHOD(clock_settime, ds1307_settime), 570 571 DEVMETHOD_END 572 }; 573 574 static driver_t ds1307_driver = { 575 "ds1307", 576 ds1307_methods, 577 sizeof(struct ds1307_softc), 578 }; 579 580 DRIVER_MODULE(ds1307, iicbus, ds1307_driver, NULL, NULL); 581 MODULE_VERSION(ds1307, 1); 582 MODULE_DEPEND(ds1307, iicbus, 1, 1, 1); 583 IICBUS_FDT_PNP_INFO(ds1307_compat_data); 584