1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * A driver for the I2C members of the Abracon AB x8xx RTC family, 4 * and compatible: AB 1805 and AB 0805 5 * 6 * Copyright 2014-2015 Macq S.A. 7 * 8 * Author: Philippe De Muyter <phdm@macqel.be> 9 * Author: Alexandre Belloni <alexandre.belloni@bootlin.com> 10 * 11 */ 12 13 #include <linux/bcd.h> 14 #include <linux/i2c.h> 15 #include <linux/module.h> 16 #include <linux/of_device.h> 17 #include <linux/rtc.h> 18 #include <linux/watchdog.h> 19 20 #define ABX8XX_REG_HTH 0x00 21 #define ABX8XX_REG_SC 0x01 22 #define ABX8XX_REG_MN 0x02 23 #define ABX8XX_REG_HR 0x03 24 #define ABX8XX_REG_DA 0x04 25 #define ABX8XX_REG_MO 0x05 26 #define ABX8XX_REG_YR 0x06 27 #define ABX8XX_REG_WD 0x07 28 29 #define ABX8XX_REG_AHTH 0x08 30 #define ABX8XX_REG_ASC 0x09 31 #define ABX8XX_REG_AMN 0x0a 32 #define ABX8XX_REG_AHR 0x0b 33 #define ABX8XX_REG_ADA 0x0c 34 #define ABX8XX_REG_AMO 0x0d 35 #define ABX8XX_REG_AWD 0x0e 36 37 #define ABX8XX_REG_STATUS 0x0f 38 #define ABX8XX_STATUS_AF BIT(2) 39 #define ABX8XX_STATUS_BLF BIT(4) 40 #define ABX8XX_STATUS_WDT BIT(6) 41 42 #define ABX8XX_REG_CTRL1 0x10 43 #define ABX8XX_CTRL_WRITE BIT(0) 44 #define ABX8XX_CTRL_ARST BIT(2) 45 #define ABX8XX_CTRL_12_24 BIT(6) 46 47 #define ABX8XX_REG_CTRL2 0x11 48 #define ABX8XX_CTRL2_RSVD BIT(5) 49 50 #define ABX8XX_REG_IRQ 0x12 51 #define ABX8XX_IRQ_AIE BIT(2) 52 #define ABX8XX_IRQ_IM_1_4 (0x3 << 5) 53 54 #define ABX8XX_REG_CD_TIMER_CTL 0x18 55 56 #define ABX8XX_REG_OSC 0x1c 57 #define ABX8XX_OSC_FOS BIT(3) 58 #define ABX8XX_OSC_BOS BIT(4) 59 #define ABX8XX_OSC_ACAL_512 BIT(5) 60 #define ABX8XX_OSC_ACAL_1024 BIT(6) 61 62 #define ABX8XX_OSC_OSEL BIT(7) 63 64 #define ABX8XX_REG_OSS 0x1d 65 #define ABX8XX_OSS_OF BIT(1) 66 #define ABX8XX_OSS_OMODE BIT(4) 67 68 #define ABX8XX_REG_WDT 0x1b 69 #define ABX8XX_WDT_WDS BIT(7) 70 #define ABX8XX_WDT_BMB_MASK 0x7c 71 #define ABX8XX_WDT_BMB_SHIFT 2 72 #define ABX8XX_WDT_MAX_TIME (ABX8XX_WDT_BMB_MASK >> ABX8XX_WDT_BMB_SHIFT) 73 #define ABX8XX_WDT_WRB_MASK 0x03 74 #define ABX8XX_WDT_WRB_1HZ 0x02 75 76 #define ABX8XX_REG_CFG_KEY 0x1f 77 #define ABX8XX_CFG_KEY_OSC 0xa1 78 #define ABX8XX_CFG_KEY_MISC 0x9d 79 80 #define ABX8XX_REG_ID0 0x28 81 82 #define ABX8XX_REG_OUT_CTRL 0x30 83 #define ABX8XX_OUT_CTRL_EXDS BIT(4) 84 85 #define ABX8XX_REG_TRICKLE 0x20 86 #define ABX8XX_TRICKLE_CHARGE_ENABLE 0xa0 87 #define ABX8XX_TRICKLE_STANDARD_DIODE 0x8 88 #define ABX8XX_TRICKLE_SCHOTTKY_DIODE 0x4 89 90 static u8 trickle_resistors[] = {0, 3, 6, 11}; 91 92 enum abx80x_chip {AB0801, AB0803, AB0804, AB0805, 93 AB1801, AB1803, AB1804, AB1805, RV1805, ABX80X}; 94 95 struct abx80x_cap { 96 u16 pn; 97 bool has_tc; 98 bool has_wdog; 99 }; 100 101 static struct abx80x_cap abx80x_caps[] = { 102 [AB0801] = {.pn = 0x0801}, 103 [AB0803] = {.pn = 0x0803}, 104 [AB0804] = {.pn = 0x0804, .has_tc = true, .has_wdog = true}, 105 [AB0805] = {.pn = 0x0805, .has_tc = true, .has_wdog = true}, 106 [AB1801] = {.pn = 0x1801}, 107 [AB1803] = {.pn = 0x1803}, 108 [AB1804] = {.pn = 0x1804, .has_tc = true, .has_wdog = true}, 109 [AB1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true}, 110 [RV1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true}, 111 [ABX80X] = {.pn = 0} 112 }; 113 114 struct abx80x_priv { 115 struct rtc_device *rtc; 116 struct i2c_client *client; 117 struct watchdog_device wdog; 118 }; 119 120 static int abx80x_is_rc_mode(struct i2c_client *client) 121 { 122 int flags = 0; 123 124 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); 125 if (flags < 0) { 126 dev_err(&client->dev, 127 "Failed to read autocalibration attribute\n"); 128 return flags; 129 } 130 131 return (flags & ABX8XX_OSS_OMODE) ? 1 : 0; 132 } 133 134 static int abx80x_enable_trickle_charger(struct i2c_client *client, 135 u8 trickle_cfg) 136 { 137 int err; 138 139 /* 140 * Write the configuration key register to enable access to the Trickle 141 * register 142 */ 143 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY, 144 ABX8XX_CFG_KEY_MISC); 145 if (err < 0) { 146 dev_err(&client->dev, "Unable to write configuration key\n"); 147 return -EIO; 148 } 149 150 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_TRICKLE, 151 ABX8XX_TRICKLE_CHARGE_ENABLE | 152 trickle_cfg); 153 if (err < 0) { 154 dev_err(&client->dev, "Unable to write trickle register\n"); 155 return -EIO; 156 } 157 158 return 0; 159 } 160 161 static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm) 162 { 163 struct i2c_client *client = to_i2c_client(dev); 164 unsigned char buf[8]; 165 int err, flags, rc_mode = 0; 166 167 /* Read the Oscillator Failure only in XT mode */ 168 rc_mode = abx80x_is_rc_mode(client); 169 if (rc_mode < 0) 170 return rc_mode; 171 172 if (!rc_mode) { 173 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); 174 if (flags < 0) 175 return flags; 176 177 if (flags & ABX8XX_OSS_OF) { 178 dev_err(dev, "Oscillator failure, data is invalid.\n"); 179 return -EINVAL; 180 } 181 } 182 183 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH, 184 sizeof(buf), buf); 185 if (err < 0) { 186 dev_err(&client->dev, "Unable to read date\n"); 187 return -EIO; 188 } 189 190 tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F); 191 tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F); 192 tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F); 193 tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7; 194 tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F); 195 tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F) - 1; 196 tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 100; 197 198 return 0; 199 } 200 201 static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm) 202 { 203 struct i2c_client *client = to_i2c_client(dev); 204 unsigned char buf[8]; 205 int err, flags; 206 207 if (tm->tm_year < 100) 208 return -EINVAL; 209 210 buf[ABX8XX_REG_HTH] = 0; 211 buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec); 212 buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min); 213 buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour); 214 buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday); 215 buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon + 1); 216 buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 100); 217 buf[ABX8XX_REG_WD] = tm->tm_wday; 218 219 err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_HTH, 220 sizeof(buf), buf); 221 if (err < 0) { 222 dev_err(&client->dev, "Unable to write to date registers\n"); 223 return -EIO; 224 } 225 226 /* Clear the OF bit of Oscillator Status Register */ 227 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); 228 if (flags < 0) 229 return flags; 230 231 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSS, 232 flags & ~ABX8XX_OSS_OF); 233 if (err < 0) { 234 dev_err(&client->dev, "Unable to write oscillator status register\n"); 235 return err; 236 } 237 238 return 0; 239 } 240 241 static irqreturn_t abx80x_handle_irq(int irq, void *dev_id) 242 { 243 struct i2c_client *client = dev_id; 244 struct abx80x_priv *priv = i2c_get_clientdata(client); 245 struct rtc_device *rtc = priv->rtc; 246 int status; 247 248 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS); 249 if (status < 0) 250 return IRQ_NONE; 251 252 if (status & ABX8XX_STATUS_AF) 253 rtc_update_irq(rtc, 1, RTC_AF | RTC_IRQF); 254 255 /* 256 * It is unclear if we'll get an interrupt before the external 257 * reset kicks in. 258 */ 259 if (status & ABX8XX_STATUS_WDT) 260 dev_alert(&client->dev, "watchdog timeout interrupt.\n"); 261 262 i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0); 263 264 return IRQ_HANDLED; 265 } 266 267 static int abx80x_read_alarm(struct device *dev, struct rtc_wkalrm *t) 268 { 269 struct i2c_client *client = to_i2c_client(dev); 270 unsigned char buf[7]; 271 272 int irq_mask, err; 273 274 if (client->irq <= 0) 275 return -EINVAL; 276 277 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC, 278 sizeof(buf), buf); 279 if (err) 280 return err; 281 282 irq_mask = i2c_smbus_read_byte_data(client, ABX8XX_REG_IRQ); 283 if (irq_mask < 0) 284 return irq_mask; 285 286 t->time.tm_sec = bcd2bin(buf[0] & 0x7F); 287 t->time.tm_min = bcd2bin(buf[1] & 0x7F); 288 t->time.tm_hour = bcd2bin(buf[2] & 0x3F); 289 t->time.tm_mday = bcd2bin(buf[3] & 0x3F); 290 t->time.tm_mon = bcd2bin(buf[4] & 0x1F) - 1; 291 t->time.tm_wday = buf[5] & 0x7; 292 293 t->enabled = !!(irq_mask & ABX8XX_IRQ_AIE); 294 t->pending = (buf[6] & ABX8XX_STATUS_AF) && t->enabled; 295 296 return err; 297 } 298 299 static int abx80x_set_alarm(struct device *dev, struct rtc_wkalrm *t) 300 { 301 struct i2c_client *client = to_i2c_client(dev); 302 u8 alarm[6]; 303 int err; 304 305 if (client->irq <= 0) 306 return -EINVAL; 307 308 alarm[0] = 0x0; 309 alarm[1] = bin2bcd(t->time.tm_sec); 310 alarm[2] = bin2bcd(t->time.tm_min); 311 alarm[3] = bin2bcd(t->time.tm_hour); 312 alarm[4] = bin2bcd(t->time.tm_mday); 313 alarm[5] = bin2bcd(t->time.tm_mon + 1); 314 315 err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_AHTH, 316 sizeof(alarm), alarm); 317 if (err < 0) { 318 dev_err(&client->dev, "Unable to write alarm registers\n"); 319 return -EIO; 320 } 321 322 if (t->enabled) { 323 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ, 324 (ABX8XX_IRQ_IM_1_4 | 325 ABX8XX_IRQ_AIE)); 326 if (err) 327 return err; 328 } 329 330 return 0; 331 } 332 333 static int abx80x_rtc_set_autocalibration(struct device *dev, 334 int autocalibration) 335 { 336 struct i2c_client *client = to_i2c_client(dev); 337 int retval, flags = 0; 338 339 if ((autocalibration != 0) && (autocalibration != 1024) && 340 (autocalibration != 512)) { 341 dev_err(dev, "autocalibration value outside permitted range\n"); 342 return -EINVAL; 343 } 344 345 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC); 346 if (flags < 0) 347 return flags; 348 349 if (autocalibration == 0) { 350 flags &= ~(ABX8XX_OSC_ACAL_512 | ABX8XX_OSC_ACAL_1024); 351 } else if (autocalibration == 1024) { 352 /* 1024 autocalibration is 0x10 */ 353 flags |= ABX8XX_OSC_ACAL_1024; 354 flags &= ~(ABX8XX_OSC_ACAL_512); 355 } else { 356 /* 512 autocalibration is 0x11 */ 357 flags |= (ABX8XX_OSC_ACAL_1024 | ABX8XX_OSC_ACAL_512); 358 } 359 360 /* Unlock write access to Oscillator Control Register */ 361 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY, 362 ABX8XX_CFG_KEY_OSC); 363 if (retval < 0) { 364 dev_err(dev, "Failed to write CONFIG_KEY register\n"); 365 return retval; 366 } 367 368 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags); 369 370 return retval; 371 } 372 373 static int abx80x_rtc_get_autocalibration(struct device *dev) 374 { 375 struct i2c_client *client = to_i2c_client(dev); 376 int flags = 0, autocalibration; 377 378 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC); 379 if (flags < 0) 380 return flags; 381 382 if (flags & ABX8XX_OSC_ACAL_512) 383 autocalibration = 512; 384 else if (flags & ABX8XX_OSC_ACAL_1024) 385 autocalibration = 1024; 386 else 387 autocalibration = 0; 388 389 return autocalibration; 390 } 391 392 static ssize_t autocalibration_store(struct device *dev, 393 struct device_attribute *attr, 394 const char *buf, size_t count) 395 { 396 int retval; 397 unsigned long autocalibration = 0; 398 399 retval = kstrtoul(buf, 10, &autocalibration); 400 if (retval < 0) { 401 dev_err(dev, "Failed to store RTC autocalibration attribute\n"); 402 return -EINVAL; 403 } 404 405 retval = abx80x_rtc_set_autocalibration(dev->parent, autocalibration); 406 407 return retval ? retval : count; 408 } 409 410 static ssize_t autocalibration_show(struct device *dev, 411 struct device_attribute *attr, char *buf) 412 { 413 int autocalibration = 0; 414 415 autocalibration = abx80x_rtc_get_autocalibration(dev->parent); 416 if (autocalibration < 0) { 417 dev_err(dev, "Failed to read RTC autocalibration\n"); 418 sprintf(buf, "0\n"); 419 return autocalibration; 420 } 421 422 return sprintf(buf, "%d\n", autocalibration); 423 } 424 425 static DEVICE_ATTR_RW(autocalibration); 426 427 static ssize_t oscillator_store(struct device *dev, 428 struct device_attribute *attr, 429 const char *buf, size_t count) 430 { 431 struct i2c_client *client = to_i2c_client(dev->parent); 432 int retval, flags, rc_mode = 0; 433 434 if (strncmp(buf, "rc", 2) == 0) { 435 rc_mode = 1; 436 } else if (strncmp(buf, "xtal", 4) == 0) { 437 rc_mode = 0; 438 } else { 439 dev_err(dev, "Oscillator selection value outside permitted ones\n"); 440 return -EINVAL; 441 } 442 443 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC); 444 if (flags < 0) 445 return flags; 446 447 if (rc_mode == 0) 448 flags &= ~(ABX8XX_OSC_OSEL); 449 else 450 flags |= (ABX8XX_OSC_OSEL); 451 452 /* Unlock write access on Oscillator Control register */ 453 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY, 454 ABX8XX_CFG_KEY_OSC); 455 if (retval < 0) { 456 dev_err(dev, "Failed to write CONFIG_KEY register\n"); 457 return retval; 458 } 459 460 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags); 461 if (retval < 0) { 462 dev_err(dev, "Failed to write Oscillator Control register\n"); 463 return retval; 464 } 465 466 return retval ? retval : count; 467 } 468 469 static ssize_t oscillator_show(struct device *dev, 470 struct device_attribute *attr, char *buf) 471 { 472 int rc_mode = 0; 473 struct i2c_client *client = to_i2c_client(dev->parent); 474 475 rc_mode = abx80x_is_rc_mode(client); 476 477 if (rc_mode < 0) { 478 dev_err(dev, "Failed to read RTC oscillator selection\n"); 479 sprintf(buf, "\n"); 480 return rc_mode; 481 } 482 483 if (rc_mode) 484 return sprintf(buf, "rc\n"); 485 else 486 return sprintf(buf, "xtal\n"); 487 } 488 489 static DEVICE_ATTR_RW(oscillator); 490 491 static struct attribute *rtc_calib_attrs[] = { 492 &dev_attr_autocalibration.attr, 493 &dev_attr_oscillator.attr, 494 NULL, 495 }; 496 497 static const struct attribute_group rtc_calib_attr_group = { 498 .attrs = rtc_calib_attrs, 499 }; 500 501 static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled) 502 { 503 struct i2c_client *client = to_i2c_client(dev); 504 int err; 505 506 if (enabled) 507 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ, 508 (ABX8XX_IRQ_IM_1_4 | 509 ABX8XX_IRQ_AIE)); 510 else 511 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ, 512 ABX8XX_IRQ_IM_1_4); 513 return err; 514 } 515 516 static int abx80x_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) 517 { 518 struct i2c_client *client = to_i2c_client(dev); 519 int status, tmp; 520 521 switch (cmd) { 522 case RTC_VL_READ: 523 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS); 524 if (status < 0) 525 return status; 526 527 tmp = status & ABX8XX_STATUS_BLF ? RTC_VL_BACKUP_LOW : 0; 528 529 return put_user(tmp, (unsigned int __user *)arg); 530 531 case RTC_VL_CLR: 532 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS); 533 if (status < 0) 534 return status; 535 536 status &= ~ABX8XX_STATUS_BLF; 537 538 tmp = i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0); 539 if (tmp < 0) 540 return tmp; 541 542 return 0; 543 544 default: 545 return -ENOIOCTLCMD; 546 } 547 } 548 549 static const struct rtc_class_ops abx80x_rtc_ops = { 550 .read_time = abx80x_rtc_read_time, 551 .set_time = abx80x_rtc_set_time, 552 .read_alarm = abx80x_read_alarm, 553 .set_alarm = abx80x_set_alarm, 554 .alarm_irq_enable = abx80x_alarm_irq_enable, 555 .ioctl = abx80x_ioctl, 556 }; 557 558 static int abx80x_dt_trickle_cfg(struct i2c_client *client) 559 { 560 struct device_node *np = client->dev.of_node; 561 const char *diode; 562 int trickle_cfg = 0; 563 int i, ret; 564 u32 tmp; 565 566 ret = of_property_read_string(np, "abracon,tc-diode", &diode); 567 if (ret) 568 return ret; 569 570 if (!strcmp(diode, "standard")) { 571 trickle_cfg |= ABX8XX_TRICKLE_STANDARD_DIODE; 572 } else if (!strcmp(diode, "schottky")) { 573 trickle_cfg |= ABX8XX_TRICKLE_SCHOTTKY_DIODE; 574 } else { 575 dev_dbg(&client->dev, "Invalid tc-diode value: %s\n", diode); 576 return -EINVAL; 577 } 578 579 ret = of_property_read_u32(np, "abracon,tc-resistor", &tmp); 580 if (ret) 581 return ret; 582 583 for (i = 0; i < sizeof(trickle_resistors); i++) 584 if (trickle_resistors[i] == tmp) 585 break; 586 587 if (i == sizeof(trickle_resistors)) { 588 dev_dbg(&client->dev, "Invalid tc-resistor value: %u\n", tmp); 589 return -EINVAL; 590 } 591 592 return (trickle_cfg | i); 593 } 594 595 #ifdef CONFIG_WATCHDOG 596 597 static inline u8 timeout_bits(unsigned int timeout) 598 { 599 return ((timeout << ABX8XX_WDT_BMB_SHIFT) & ABX8XX_WDT_BMB_MASK) | 600 ABX8XX_WDT_WRB_1HZ; 601 } 602 603 static int __abx80x_wdog_set_timeout(struct watchdog_device *wdog, 604 unsigned int timeout) 605 { 606 struct abx80x_priv *priv = watchdog_get_drvdata(wdog); 607 u8 val = ABX8XX_WDT_WDS | timeout_bits(timeout); 608 609 /* 610 * Writing any timeout to the WDT register resets the watchdog timer. 611 * Writing 0 disables it. 612 */ 613 return i2c_smbus_write_byte_data(priv->client, ABX8XX_REG_WDT, val); 614 } 615 616 static int abx80x_wdog_set_timeout(struct watchdog_device *wdog, 617 unsigned int new_timeout) 618 { 619 int err = 0; 620 621 if (watchdog_hw_running(wdog)) 622 err = __abx80x_wdog_set_timeout(wdog, new_timeout); 623 624 if (err == 0) 625 wdog->timeout = new_timeout; 626 627 return err; 628 } 629 630 static int abx80x_wdog_ping(struct watchdog_device *wdog) 631 { 632 return __abx80x_wdog_set_timeout(wdog, wdog->timeout); 633 } 634 635 static int abx80x_wdog_start(struct watchdog_device *wdog) 636 { 637 return __abx80x_wdog_set_timeout(wdog, wdog->timeout); 638 } 639 640 static int abx80x_wdog_stop(struct watchdog_device *wdog) 641 { 642 return __abx80x_wdog_set_timeout(wdog, 0); 643 } 644 645 static const struct watchdog_info abx80x_wdog_info = { 646 .identity = "abx80x watchdog", 647 .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, 648 }; 649 650 static const struct watchdog_ops abx80x_wdog_ops = { 651 .owner = THIS_MODULE, 652 .start = abx80x_wdog_start, 653 .stop = abx80x_wdog_stop, 654 .ping = abx80x_wdog_ping, 655 .set_timeout = abx80x_wdog_set_timeout, 656 }; 657 658 static int abx80x_setup_watchdog(struct abx80x_priv *priv) 659 { 660 priv->wdog.parent = &priv->client->dev; 661 priv->wdog.ops = &abx80x_wdog_ops; 662 priv->wdog.info = &abx80x_wdog_info; 663 priv->wdog.min_timeout = 1; 664 priv->wdog.max_timeout = ABX8XX_WDT_MAX_TIME; 665 priv->wdog.timeout = ABX8XX_WDT_MAX_TIME; 666 667 watchdog_set_drvdata(&priv->wdog, priv); 668 669 return devm_watchdog_register_device(&priv->client->dev, &priv->wdog); 670 } 671 #else 672 static int abx80x_setup_watchdog(struct abx80x_priv *priv) 673 { 674 return 0; 675 } 676 #endif 677 678 static int abx80x_probe(struct i2c_client *client, 679 const struct i2c_device_id *id) 680 { 681 struct device_node *np = client->dev.of_node; 682 struct abx80x_priv *priv; 683 int i, data, err, trickle_cfg = -EINVAL; 684 char buf[7]; 685 unsigned int part = id->driver_data; 686 unsigned int partnumber; 687 unsigned int majrev, minrev; 688 unsigned int lot; 689 unsigned int wafer; 690 unsigned int uid; 691 692 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) 693 return -ENODEV; 694 695 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ID0, 696 sizeof(buf), buf); 697 if (err < 0) { 698 dev_err(&client->dev, "Unable to read partnumber\n"); 699 return -EIO; 700 } 701 702 partnumber = (buf[0] << 8) | buf[1]; 703 majrev = buf[2] >> 3; 704 minrev = buf[2] & 0x7; 705 lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3]; 706 uid = ((buf[4] & 0x7f) << 8) | buf[5]; 707 wafer = (buf[6] & 0x7c) >> 2; 708 dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n", 709 partnumber, majrev, minrev, lot, wafer, uid); 710 711 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL1); 712 if (data < 0) { 713 dev_err(&client->dev, "Unable to read control register\n"); 714 return -EIO; 715 } 716 717 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1, 718 ((data & ~(ABX8XX_CTRL_12_24 | 719 ABX8XX_CTRL_ARST)) | 720 ABX8XX_CTRL_WRITE)); 721 if (err < 0) { 722 dev_err(&client->dev, "Unable to write control register\n"); 723 return -EIO; 724 } 725 726 /* Configure RV1805 specifics */ 727 if (part == RV1805) { 728 /* 729 * Avoid accidentally entering test mode. This can happen 730 * on the RV1805 in case the reserved bit 5 in control2 731 * register is set. RV-1805-C3 datasheet indicates that 732 * the bit should be cleared in section 11h - Control2. 733 */ 734 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL2); 735 if (data < 0) { 736 dev_err(&client->dev, 737 "Unable to read control2 register\n"); 738 return -EIO; 739 } 740 741 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL2, 742 data & ~ABX8XX_CTRL2_RSVD); 743 if (err < 0) { 744 dev_err(&client->dev, 745 "Unable to write control2 register\n"); 746 return -EIO; 747 } 748 749 /* 750 * Avoid extra power leakage. The RV1805 uses smaller 751 * 10pin package and the EXTI input is not present. 752 * Disable it to avoid leakage. 753 */ 754 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_OUT_CTRL); 755 if (data < 0) { 756 dev_err(&client->dev, 757 "Unable to read output control register\n"); 758 return -EIO; 759 } 760 761 /* 762 * Write the configuration key register to enable access to 763 * the config2 register 764 */ 765 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY, 766 ABX8XX_CFG_KEY_MISC); 767 if (err < 0) { 768 dev_err(&client->dev, 769 "Unable to write configuration key\n"); 770 return -EIO; 771 } 772 773 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OUT_CTRL, 774 data | ABX8XX_OUT_CTRL_EXDS); 775 if (err < 0) { 776 dev_err(&client->dev, 777 "Unable to write output control register\n"); 778 return -EIO; 779 } 780 } 781 782 /* part autodetection */ 783 if (part == ABX80X) { 784 for (i = 0; abx80x_caps[i].pn; i++) 785 if (partnumber == abx80x_caps[i].pn) 786 break; 787 if (abx80x_caps[i].pn == 0) { 788 dev_err(&client->dev, "Unknown part: %04x\n", 789 partnumber); 790 return -EINVAL; 791 } 792 part = i; 793 } 794 795 if (partnumber != abx80x_caps[part].pn) { 796 dev_err(&client->dev, "partnumber mismatch %04x != %04x\n", 797 partnumber, abx80x_caps[part].pn); 798 return -EINVAL; 799 } 800 801 if (np && abx80x_caps[part].has_tc) 802 trickle_cfg = abx80x_dt_trickle_cfg(client); 803 804 if (trickle_cfg > 0) { 805 dev_info(&client->dev, "Enabling trickle charger: %02x\n", 806 trickle_cfg); 807 abx80x_enable_trickle_charger(client, trickle_cfg); 808 } 809 810 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL, 811 BIT(2)); 812 if (err) 813 return err; 814 815 priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL); 816 if (priv == NULL) 817 return -ENOMEM; 818 819 priv->rtc = devm_rtc_allocate_device(&client->dev); 820 if (IS_ERR(priv->rtc)) 821 return PTR_ERR(priv->rtc); 822 823 priv->rtc->ops = &abx80x_rtc_ops; 824 priv->client = client; 825 826 i2c_set_clientdata(client, priv); 827 828 if (abx80x_caps[part].has_wdog) { 829 err = abx80x_setup_watchdog(priv); 830 if (err) 831 return err; 832 } 833 834 if (client->irq > 0) { 835 dev_info(&client->dev, "IRQ %d supplied\n", client->irq); 836 err = devm_request_threaded_irq(&client->dev, client->irq, NULL, 837 abx80x_handle_irq, 838 IRQF_SHARED | IRQF_ONESHOT, 839 "abx8xx", 840 client); 841 if (err) { 842 dev_err(&client->dev, "unable to request IRQ, alarms disabled\n"); 843 client->irq = 0; 844 } 845 } 846 847 err = rtc_add_group(priv->rtc, &rtc_calib_attr_group); 848 if (err) { 849 dev_err(&client->dev, "Failed to create sysfs group: %d\n", 850 err); 851 return err; 852 } 853 854 return rtc_register_device(priv->rtc); 855 } 856 857 static const struct i2c_device_id abx80x_id[] = { 858 { "abx80x", ABX80X }, 859 { "ab0801", AB0801 }, 860 { "ab0803", AB0803 }, 861 { "ab0804", AB0804 }, 862 { "ab0805", AB0805 }, 863 { "ab1801", AB1801 }, 864 { "ab1803", AB1803 }, 865 { "ab1804", AB1804 }, 866 { "ab1805", AB1805 }, 867 { "rv1805", RV1805 }, 868 { } 869 }; 870 MODULE_DEVICE_TABLE(i2c, abx80x_id); 871 872 #ifdef CONFIG_OF 873 static const struct of_device_id abx80x_of_match[] = { 874 { 875 .compatible = "abracon,abx80x", 876 .data = (void *)ABX80X 877 }, 878 { 879 .compatible = "abracon,ab0801", 880 .data = (void *)AB0801 881 }, 882 { 883 .compatible = "abracon,ab0803", 884 .data = (void *)AB0803 885 }, 886 { 887 .compatible = "abracon,ab0804", 888 .data = (void *)AB0804 889 }, 890 { 891 .compatible = "abracon,ab0805", 892 .data = (void *)AB0805 893 }, 894 { 895 .compatible = "abracon,ab1801", 896 .data = (void *)AB1801 897 }, 898 { 899 .compatible = "abracon,ab1803", 900 .data = (void *)AB1803 901 }, 902 { 903 .compatible = "abracon,ab1804", 904 .data = (void *)AB1804 905 }, 906 { 907 .compatible = "abracon,ab1805", 908 .data = (void *)AB1805 909 }, 910 { 911 .compatible = "microcrystal,rv1805", 912 .data = (void *)RV1805 913 }, 914 { } 915 }; 916 MODULE_DEVICE_TABLE(of, abx80x_of_match); 917 #endif 918 919 static struct i2c_driver abx80x_driver = { 920 .driver = { 921 .name = "rtc-abx80x", 922 .of_match_table = of_match_ptr(abx80x_of_match), 923 }, 924 .probe = abx80x_probe, 925 .id_table = abx80x_id, 926 }; 927 928 module_i2c_driver(abx80x_driver); 929 930 MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>"); 931 MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>"); 932 MODULE_DESCRIPTION("Abracon ABX80X RTC driver"); 933 MODULE_LICENSE("GPL v2"); 934