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_MCP7941X, 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_MCP7941X}, 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_MCP7941X) 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 switch(compat->ocd_data) { 230 case TYPE_DS1307: 231 device_set_desc(dev, "Dallas DS1307"); 232 break; 233 case TYPE_MAXIM1307: 234 device_set_desc(dev, "Maxim DS1307"); 235 break; 236 case TYPE_MICROCHIP_MCP7941X: 237 device_set_desc(dev, "Microchip MCP7941X"); 238 break; 239 case TYPE_EPSON_RX8035: 240 device_set_desc(dev, "Epson RX-8035"); 241 break; 242 default: 243 device_set_desc(dev, "Unknown DS1307-like device"); 244 break; 245 } 246 return (BUS_PROBE_DEFAULT); 247 } 248 #endif 249 250 device_set_desc(dev, "Maxim DS1307"); 251 return (BUS_PROBE_NOWILDCARD); 252 } 253 254 static int 255 ds1307_attach(device_t dev) 256 { 257 #ifdef FDT 258 const struct ofw_compat_data *compat; 259 #endif 260 struct ds1307_softc *sc; 261 262 sc = device_get_softc(dev); 263 sc->sc_dev = dev; 264 sc->enum_hook.ich_func = ds1307_start; 265 sc->enum_hook.ich_arg = dev; 266 #ifdef FDT 267 compat = ofw_bus_search_compatible(dev, ds1307_compat_data); 268 sc->chiptype = compat->ocd_data; 269 /* Unify the chiptypes to DS1307 where possible. */ 270 if (sc->chiptype == TYPE_MAXIM1307) 271 sc->chiptype = TYPE_DS1307; 272 #else 273 sc->chiptype = TYPE_DS1307; 274 #endif 275 276 /* 277 * We have to wait until interrupts are enabled. Usually I2C read 278 * and write only works when the interrupts are available. 279 */ 280 if (config_intrhook_establish(&sc->enum_hook) != 0) 281 return (ENOMEM); 282 283 return (0); 284 } 285 286 static int 287 ds1307_detach(device_t dev) 288 { 289 290 clock_unregister(dev); 291 return (0); 292 } 293 294 static bool 295 is_epson_time_valid(struct ds1307_softc *sc) 296 { 297 device_t dev; 298 int error; 299 uint8_t ctrl2; 300 301 dev = sc->sc_dev; 302 303 /* 304 * The RX-8035 single register read is non-standard 305 * Refer to section 8.9.5 of the RX-8035 application manual: 306 * "I2C bus basic transfer format", under "Standard Read Method". 307 * Basically, register to read goes into the top 4 bits. 308 */ 309 error = ds1307_read1(dev, (RX8035_CTRL_2 << 4), &ctrl2); 310 if (error) { 311 device_printf(dev, "%s cannot read Control 2 register: %d\n", 312 __func__, error); 313 return (false); 314 } 315 316 if (ctrl2 & RX8035_CTRL_2_XSTP) { 317 device_printf(dev, "Oscillation stop detected (ctrl2=%#02x)\n", 318 ctrl2); 319 return (false); 320 } 321 322 /* 323 * Power on reset (PON) generally implies oscillation stop, 324 * but catch it as well to be sure. 325 */ 326 if (ctrl2 & RX8035_CTRL_2_PON) { 327 device_printf(dev, "Power-on reset detected (ctrl2=%#02x)\n", 328 ctrl2); 329 return (false); 330 } 331 332 return (true); 333 } 334 335 static int 336 mark_epson_time_valid(struct ds1307_softc *sc) 337 { 338 device_t dev; 339 int error; 340 uint8_t ctrl2; 341 uint8_t control_mask; 342 343 dev = sc->sc_dev; 344 345 error = ds1307_read1(dev, (RX8035_CTRL_2 << 4), &ctrl2); 346 if (error) { 347 device_printf(dev, "%s cannot read Control 2 register: %d\n", 348 __func__, error); 349 return (false); 350 } 351 352 control_mask = (RX8035_CTRL_2_PON | RX8035_CTRL_2_XSTP | RX8035_CTRL_2_VDET); 353 ctrl2 = ctrl2 & ~(control_mask); 354 355 error = ds1307_write1(dev, (RX8035_CTRL_2 << 4), ctrl2); 356 if (error) { 357 device_printf(dev, "%s cannot write to Control 2 register: %d\n", 358 __func__, error); 359 return (false); 360 } 361 return (true); 362 } 363 364 static bool is_dev_time_valid(struct ds1307_softc *sc) 365 { 366 device_t dev; 367 int error; 368 uint8_t osc_en; 369 uint8_t secs; 370 371 /* Epson RTCs have different control/status registers. */ 372 if (sc->chiptype == TYPE_EPSON_RX8035) 373 return (is_epson_time_valid(sc)); 374 375 dev = sc->sc_dev; 376 /* Check if the oscillator is disabled. */ 377 error = ds1307_read1(dev, DS1307_SECS, &secs); 378 if (error) { 379 device_printf(dev, "%s: cannot read from RTC: %d\n", 380 __func__, error); 381 return (false); 382 } 383 384 switch (sc->chiptype) { 385 case TYPE_MICROCHIP_MCP7941X: 386 osc_en = 0x80; 387 break; 388 default: 389 osc_en = 0x00; 390 break; 391 } 392 if (((secs & DS1307_SECS_CH) ^ osc_en) != 0) 393 return (false); 394 395 return (true); 396 } 397 398 static void 399 ds1307_start(void *xdev) 400 { 401 device_t dev; 402 struct ds1307_softc *sc; 403 struct sysctl_ctx_list *ctx; 404 struct sysctl_oid *tree_node; 405 struct sysctl_oid_list *tree; 406 407 dev = (device_t)xdev; 408 sc = device_get_softc(dev); 409 410 config_intrhook_disestablish(&sc->enum_hook); 411 412 if (!is_dev_time_valid(sc)) 413 device_printf(dev, 414 "WARNING: RTC clock stopped, check the battery.\n"); 415 416 /* 417 * Configuration parameters: 418 * square wave output cannot be changed or inhibited on the RX-8035, 419 * so don't present the sysctls there. 420 */ 421 if (sc->chiptype == TYPE_EPSON_RX8035) 422 goto skip_sysctl; 423 424 ctx = device_get_sysctl_ctx(dev); 425 tree_node = device_get_sysctl_tree(dev); 426 tree = SYSCTL_CHILDREN(tree_node); 427 428 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "sqwe", 429 CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_MPSAFE, sc, 0, 430 ds1307_sqwe_sysctl, "IU", "DS1307 square-wave enable"); 431 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "sqw_freq", 432 CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_MPSAFE, sc, 0, 433 ds1307_sqw_freq_sysctl, "IU", 434 "DS1307 square-wave output frequency"); 435 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "sqw_out", 436 CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_MPSAFE, sc, 0, 437 ds1307_sqw_out_sysctl, "IU", "DS1307 square-wave output state"); 438 skip_sysctl: 439 440 /* 441 * Register as a clock with 1 second resolution. Schedule the 442 * clock_settime() method to be called just after top-of-second; 443 * resetting the time resets top-of-second in the hardware. 444 */ 445 clock_register_flags(dev, 1000000, CLOCKF_SETTIME_NO_ADJ); 446 clock_schedule(dev, 1); 447 } 448 449 static int 450 ds1307_gettime(device_t dev, struct timespec *ts) 451 { 452 struct bcd_clocktime bct; 453 struct ds1307_softc *sc; 454 int error; 455 uint8_t data[7], hourmask, ampm_mode; 456 457 sc = device_get_softc(dev); 458 error = iicdev_readfrom(sc->sc_dev, DS1307_SECS, data, sizeof(data), 459 IIC_INTRWAIT); 460 if (error != 0) { 461 device_printf(dev, "%s: cannot read from RTC: %d\n", 462 __func__, error); 463 return (error); 464 } 465 466 if (!is_dev_time_valid(sc)) { 467 device_printf(dev, "Device time not valid.\n"); 468 return (EINVAL); 469 } 470 471 /* 472 * If the chip is in AM/PM mode remember that. 473 * The EPSON uses a 1 to signify 24 hour mode, while the DS uses a 0, 474 * in slightly different positions. 475 */ 476 if (sc->chiptype == TYPE_EPSON_RX8035) 477 ampm_mode = !(data[DS1307_HOUR] & RX8035_HOUR_USE_24); 478 else 479 ampm_mode = data[DS1307_HOUR] & DS1307_HOUR_USE_AMPM; 480 481 if (ampm_mode) { 482 sc->sc_use_ampm = true; 483 hourmask = DS1307_HOUR_MASK_12HR; 484 } else 485 hourmask = DS1307_HOUR_MASK_24HR; 486 487 bct.nsec = 0; 488 bct.ispm = (data[DS1307_HOUR] & DS1307_HOUR_IS_PM) != 0; 489 bct.sec = data[DS1307_SECS] & DS1307_SECS_MASK; 490 bct.min = data[DS1307_MINS] & DS1307_MINS_MASK; 491 bct.hour = data[DS1307_HOUR] & hourmask; 492 bct.day = data[DS1307_DATE] & DS1307_DATE_MASK; 493 bct.mon = data[DS1307_MONTH] & DS1307_MONTH_MASK; 494 bct.year = data[DS1307_YEAR] & DS1307_YEAR_MASK; 495 496 clock_dbgprint_bcd(sc->sc_dev, CLOCK_DBG_READ, &bct); 497 return (clock_bcd_to_ts(&bct, ts, sc->sc_use_ampm)); 498 } 499 500 static int 501 ds1307_settime(device_t dev, struct timespec *ts) 502 { 503 struct bcd_clocktime bct; 504 struct ds1307_softc *sc; 505 int error, year; 506 uint8_t data[7]; 507 uint8_t pmflags; 508 509 sc = device_get_softc(dev); 510 511 /* 512 * We request a timespec with no resolution-adjustment. That also 513 * disables utc adjustment, so apply that ourselves. 514 */ 515 ts->tv_sec -= utc_offset(); 516 clock_ts_to_bcd(ts, &bct, sc->sc_use_ampm); 517 clock_dbgprint_bcd(sc->sc_dev, CLOCK_DBG_WRITE, &bct); 518 519 /* 520 * If the chip is in AM/PM mode, adjust hour and set flags as needed. 521 * The AM/PM bit polarity and position is different on the EPSON. 522 */ 523 if (sc->sc_use_ampm) { 524 pmflags = (sc->chiptype != TYPE_EPSON_RX8035) ? 525 DS1307_HOUR_USE_AMPM : 0; 526 if (bct.ispm) 527 pmflags |= DS1307_HOUR_IS_PM; 528 529 } else if (sc->chiptype == TYPE_EPSON_RX8035) 530 pmflags = RX8035_HOUR_USE_24; 531 else 532 pmflags = 0; 533 534 data[DS1307_SECS] = bct.sec; 535 data[DS1307_MINS] = bct.min; 536 data[DS1307_HOUR] = bct.hour | pmflags; 537 data[DS1307_DATE] = bct.day; 538 data[DS1307_WEEKDAY] = bct.dow; 539 data[DS1307_MONTH] = bct.mon; 540 data[DS1307_YEAR] = bct.year & 0xff; 541 if (sc->chiptype == TYPE_MICROCHIP_MCP7941X) { 542 data[DS1307_SECS] |= MCP7941X_SECS_ST; 543 data[DS1307_WEEKDAY] |= MCP7941X_WEEKDAY_VBATEN; 544 year = bcd2bin(bct.year >> 8) * 100 + bcd2bin(bct.year & 0xff); 545 if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0) 546 data[DS1307_MONTH] |= MCP7941X_MONTH_LPYR; 547 } 548 549 /* Write the time back to RTC. */ 550 error = iicdev_writeto(sc->sc_dev, DS1307_SECS, data, sizeof(data), 551 IIC_INTRWAIT); 552 if (error != 0) 553 device_printf(dev, "%s: cannot write to RTC: %d\n", 554 __func__, error); 555 556 if (sc->chiptype == TYPE_EPSON_RX8035) 557 error = mark_epson_time_valid(sc); 558 559 return (error); 560 } 561 562 static device_method_t ds1307_methods[] = { 563 DEVMETHOD(device_probe, ds1307_probe), 564 DEVMETHOD(device_attach, ds1307_attach), 565 DEVMETHOD(device_detach, ds1307_detach), 566 567 DEVMETHOD(clock_gettime, ds1307_gettime), 568 DEVMETHOD(clock_settime, ds1307_settime), 569 570 DEVMETHOD_END 571 }; 572 573 static driver_t ds1307_driver = { 574 "ds1307", 575 ds1307_methods, 576 sizeof(struct ds1307_softc), 577 }; 578 579 DRIVER_MODULE(ds1307, iicbus, ds1307_driver, NULL, NULL); 580 MODULE_VERSION(ds1307, 1); 581 MODULE_DEPEND(ds1307, iicbus, 1, 1, 1); 582 IICBUS_FDT_PNP_INFO(ds1307_compat_data); 583