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_write_config_key(struct i2c_client *client, u8 key) 121 { 122 if (i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY, key) < 0) { 123 dev_err(&client->dev, "Unable to write configuration key\n"); 124 return -EIO; 125 } 126 127 return 0; 128 } 129 130 static int abx80x_is_rc_mode(struct i2c_client *client) 131 { 132 int flags = 0; 133 134 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); 135 if (flags < 0) { 136 dev_err(&client->dev, 137 "Failed to read autocalibration attribute\n"); 138 return flags; 139 } 140 141 return (flags & ABX8XX_OSS_OMODE) ? 1 : 0; 142 } 143 144 static int abx80x_enable_trickle_charger(struct i2c_client *client, 145 u8 trickle_cfg) 146 { 147 int err; 148 149 /* 150 * Write the configuration key register to enable access to the Trickle 151 * register 152 */ 153 if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_MISC) < 0) 154 return -EIO; 155 156 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_TRICKLE, 157 ABX8XX_TRICKLE_CHARGE_ENABLE | 158 trickle_cfg); 159 if (err < 0) { 160 dev_err(&client->dev, "Unable to write trickle register\n"); 161 return -EIO; 162 } 163 164 return 0; 165 } 166 167 static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm) 168 { 169 struct i2c_client *client = to_i2c_client(dev); 170 unsigned char buf[8]; 171 int err, flags, rc_mode = 0; 172 173 /* Read the Oscillator Failure only in XT mode */ 174 rc_mode = abx80x_is_rc_mode(client); 175 if (rc_mode < 0) 176 return rc_mode; 177 178 if (!rc_mode) { 179 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); 180 if (flags < 0) 181 return flags; 182 183 if (flags & ABX8XX_OSS_OF) { 184 dev_err(dev, "Oscillator failure, data is invalid.\n"); 185 return -EINVAL; 186 } 187 } 188 189 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH, 190 sizeof(buf), buf); 191 if (err < 0) { 192 dev_err(&client->dev, "Unable to read date\n"); 193 return -EIO; 194 } 195 196 tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F); 197 tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F); 198 tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F); 199 tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7; 200 tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F); 201 tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F) - 1; 202 tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 100; 203 204 return 0; 205 } 206 207 static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm) 208 { 209 struct i2c_client *client = to_i2c_client(dev); 210 unsigned char buf[8]; 211 int err, flags; 212 213 if (tm->tm_year < 100) 214 return -EINVAL; 215 216 buf[ABX8XX_REG_HTH] = 0; 217 buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec); 218 buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min); 219 buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour); 220 buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday); 221 buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon + 1); 222 buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 100); 223 buf[ABX8XX_REG_WD] = tm->tm_wday; 224 225 err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_HTH, 226 sizeof(buf), buf); 227 if (err < 0) { 228 dev_err(&client->dev, "Unable to write to date registers\n"); 229 return -EIO; 230 } 231 232 /* Clear the OF bit of Oscillator Status Register */ 233 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); 234 if (flags < 0) 235 return flags; 236 237 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSS, 238 flags & ~ABX8XX_OSS_OF); 239 if (err < 0) { 240 dev_err(&client->dev, "Unable to write oscillator status register\n"); 241 return err; 242 } 243 244 return 0; 245 } 246 247 static irqreturn_t abx80x_handle_irq(int irq, void *dev_id) 248 { 249 struct i2c_client *client = dev_id; 250 struct abx80x_priv *priv = i2c_get_clientdata(client); 251 struct rtc_device *rtc = priv->rtc; 252 int status; 253 254 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS); 255 if (status < 0) 256 return IRQ_NONE; 257 258 if (status & ABX8XX_STATUS_AF) 259 rtc_update_irq(rtc, 1, RTC_AF | RTC_IRQF); 260 261 /* 262 * It is unclear if we'll get an interrupt before the external 263 * reset kicks in. 264 */ 265 if (status & ABX8XX_STATUS_WDT) 266 dev_alert(&client->dev, "watchdog timeout interrupt.\n"); 267 268 i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0); 269 270 return IRQ_HANDLED; 271 } 272 273 static int abx80x_read_alarm(struct device *dev, struct rtc_wkalrm *t) 274 { 275 struct i2c_client *client = to_i2c_client(dev); 276 unsigned char buf[7]; 277 278 int irq_mask, err; 279 280 if (client->irq <= 0) 281 return -EINVAL; 282 283 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC, 284 sizeof(buf), buf); 285 if (err) 286 return err; 287 288 irq_mask = i2c_smbus_read_byte_data(client, ABX8XX_REG_IRQ); 289 if (irq_mask < 0) 290 return irq_mask; 291 292 t->time.tm_sec = bcd2bin(buf[0] & 0x7F); 293 t->time.tm_min = bcd2bin(buf[1] & 0x7F); 294 t->time.tm_hour = bcd2bin(buf[2] & 0x3F); 295 t->time.tm_mday = bcd2bin(buf[3] & 0x3F); 296 t->time.tm_mon = bcd2bin(buf[4] & 0x1F) - 1; 297 t->time.tm_wday = buf[5] & 0x7; 298 299 t->enabled = !!(irq_mask & ABX8XX_IRQ_AIE); 300 t->pending = (buf[6] & ABX8XX_STATUS_AF) && t->enabled; 301 302 return err; 303 } 304 305 static int abx80x_set_alarm(struct device *dev, struct rtc_wkalrm *t) 306 { 307 struct i2c_client *client = to_i2c_client(dev); 308 u8 alarm[6]; 309 int err; 310 311 if (client->irq <= 0) 312 return -EINVAL; 313 314 alarm[0] = 0x0; 315 alarm[1] = bin2bcd(t->time.tm_sec); 316 alarm[2] = bin2bcd(t->time.tm_min); 317 alarm[3] = bin2bcd(t->time.tm_hour); 318 alarm[4] = bin2bcd(t->time.tm_mday); 319 alarm[5] = bin2bcd(t->time.tm_mon + 1); 320 321 err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_AHTH, 322 sizeof(alarm), alarm); 323 if (err < 0) { 324 dev_err(&client->dev, "Unable to write alarm registers\n"); 325 return -EIO; 326 } 327 328 if (t->enabled) { 329 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ, 330 (ABX8XX_IRQ_IM_1_4 | 331 ABX8XX_IRQ_AIE)); 332 if (err) 333 return err; 334 } 335 336 return 0; 337 } 338 339 static int abx80x_rtc_set_autocalibration(struct device *dev, 340 int autocalibration) 341 { 342 struct i2c_client *client = to_i2c_client(dev); 343 int retval, flags = 0; 344 345 if ((autocalibration != 0) && (autocalibration != 1024) && 346 (autocalibration != 512)) { 347 dev_err(dev, "autocalibration value outside permitted range\n"); 348 return -EINVAL; 349 } 350 351 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC); 352 if (flags < 0) 353 return flags; 354 355 if (autocalibration == 0) { 356 flags &= ~(ABX8XX_OSC_ACAL_512 | ABX8XX_OSC_ACAL_1024); 357 } else if (autocalibration == 1024) { 358 /* 1024 autocalibration is 0x10 */ 359 flags |= ABX8XX_OSC_ACAL_1024; 360 flags &= ~(ABX8XX_OSC_ACAL_512); 361 } else { 362 /* 512 autocalibration is 0x11 */ 363 flags |= (ABX8XX_OSC_ACAL_1024 | ABX8XX_OSC_ACAL_512); 364 } 365 366 /* Unlock write access to Oscillator Control Register */ 367 if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_OSC) < 0) 368 return -EIO; 369 370 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags); 371 372 return retval; 373 } 374 375 static int abx80x_rtc_get_autocalibration(struct device *dev) 376 { 377 struct i2c_client *client = to_i2c_client(dev); 378 int flags = 0, autocalibration; 379 380 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC); 381 if (flags < 0) 382 return flags; 383 384 if (flags & ABX8XX_OSC_ACAL_512) 385 autocalibration = 512; 386 else if (flags & ABX8XX_OSC_ACAL_1024) 387 autocalibration = 1024; 388 else 389 autocalibration = 0; 390 391 return autocalibration; 392 } 393 394 static ssize_t autocalibration_store(struct device *dev, 395 struct device_attribute *attr, 396 const char *buf, size_t count) 397 { 398 int retval; 399 unsigned long autocalibration = 0; 400 401 retval = kstrtoul(buf, 10, &autocalibration); 402 if (retval < 0) { 403 dev_err(dev, "Failed to store RTC autocalibration attribute\n"); 404 return -EINVAL; 405 } 406 407 retval = abx80x_rtc_set_autocalibration(dev->parent, autocalibration); 408 409 return retval ? retval : count; 410 } 411 412 static ssize_t autocalibration_show(struct device *dev, 413 struct device_attribute *attr, char *buf) 414 { 415 int autocalibration = 0; 416 417 autocalibration = abx80x_rtc_get_autocalibration(dev->parent); 418 if (autocalibration < 0) { 419 dev_err(dev, "Failed to read RTC autocalibration\n"); 420 sprintf(buf, "0\n"); 421 return autocalibration; 422 } 423 424 return sprintf(buf, "%d\n", autocalibration); 425 } 426 427 static DEVICE_ATTR_RW(autocalibration); 428 429 static ssize_t oscillator_store(struct device *dev, 430 struct device_attribute *attr, 431 const char *buf, size_t count) 432 { 433 struct i2c_client *client = to_i2c_client(dev->parent); 434 int retval, flags, rc_mode = 0; 435 436 if (strncmp(buf, "rc", 2) == 0) { 437 rc_mode = 1; 438 } else if (strncmp(buf, "xtal", 4) == 0) { 439 rc_mode = 0; 440 } else { 441 dev_err(dev, "Oscillator selection value outside permitted ones\n"); 442 return -EINVAL; 443 } 444 445 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC); 446 if (flags < 0) 447 return flags; 448 449 if (rc_mode == 0) 450 flags &= ~(ABX8XX_OSC_OSEL); 451 else 452 flags |= (ABX8XX_OSC_OSEL); 453 454 /* Unlock write access on Oscillator Control register */ 455 if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_OSC) < 0) 456 return -EIO; 457 458 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags); 459 if (retval < 0) { 460 dev_err(dev, "Failed to write Oscillator Control register\n"); 461 return retval; 462 } 463 464 return retval ? retval : count; 465 } 466 467 static ssize_t oscillator_show(struct device *dev, 468 struct device_attribute *attr, char *buf) 469 { 470 int rc_mode = 0; 471 struct i2c_client *client = to_i2c_client(dev->parent); 472 473 rc_mode = abx80x_is_rc_mode(client); 474 475 if (rc_mode < 0) { 476 dev_err(dev, "Failed to read RTC oscillator selection\n"); 477 sprintf(buf, "\n"); 478 return rc_mode; 479 } 480 481 if (rc_mode) 482 return sprintf(buf, "rc\n"); 483 else 484 return sprintf(buf, "xtal\n"); 485 } 486 487 static DEVICE_ATTR_RW(oscillator); 488 489 static struct attribute *rtc_calib_attrs[] = { 490 &dev_attr_autocalibration.attr, 491 &dev_attr_oscillator.attr, 492 NULL, 493 }; 494 495 static const struct attribute_group rtc_calib_attr_group = { 496 .attrs = rtc_calib_attrs, 497 }; 498 499 static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled) 500 { 501 struct i2c_client *client = to_i2c_client(dev); 502 int err; 503 504 if (enabled) 505 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ, 506 (ABX8XX_IRQ_IM_1_4 | 507 ABX8XX_IRQ_AIE)); 508 else 509 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ, 510 ABX8XX_IRQ_IM_1_4); 511 return err; 512 } 513 514 static int abx80x_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) 515 { 516 struct i2c_client *client = to_i2c_client(dev); 517 int status, tmp; 518 519 switch (cmd) { 520 case RTC_VL_READ: 521 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS); 522 if (status < 0) 523 return status; 524 525 tmp = status & ABX8XX_STATUS_BLF ? RTC_VL_BACKUP_LOW : 0; 526 527 return put_user(tmp, (unsigned int __user *)arg); 528 529 case RTC_VL_CLR: 530 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS); 531 if (status < 0) 532 return status; 533 534 status &= ~ABX8XX_STATUS_BLF; 535 536 tmp = i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0); 537 if (tmp < 0) 538 return tmp; 539 540 return 0; 541 542 default: 543 return -ENOIOCTLCMD; 544 } 545 } 546 547 static const struct rtc_class_ops abx80x_rtc_ops = { 548 .read_time = abx80x_rtc_read_time, 549 .set_time = abx80x_rtc_set_time, 550 .read_alarm = abx80x_read_alarm, 551 .set_alarm = abx80x_set_alarm, 552 .alarm_irq_enable = abx80x_alarm_irq_enable, 553 .ioctl = abx80x_ioctl, 554 }; 555 556 static int abx80x_dt_trickle_cfg(struct i2c_client *client) 557 { 558 struct device_node *np = client->dev.of_node; 559 const char *diode; 560 int trickle_cfg = 0; 561 int i, ret; 562 u32 tmp; 563 564 ret = of_property_read_string(np, "abracon,tc-diode", &diode); 565 if (ret) 566 return ret; 567 568 if (!strcmp(diode, "standard")) { 569 trickle_cfg |= ABX8XX_TRICKLE_STANDARD_DIODE; 570 } else if (!strcmp(diode, "schottky")) { 571 trickle_cfg |= ABX8XX_TRICKLE_SCHOTTKY_DIODE; 572 } else { 573 dev_dbg(&client->dev, "Invalid tc-diode value: %s\n", diode); 574 return -EINVAL; 575 } 576 577 ret = of_property_read_u32(np, "abracon,tc-resistor", &tmp); 578 if (ret) 579 return ret; 580 581 for (i = 0; i < sizeof(trickle_resistors); i++) 582 if (trickle_resistors[i] == tmp) 583 break; 584 585 if (i == sizeof(trickle_resistors)) { 586 dev_dbg(&client->dev, "Invalid tc-resistor value: %u\n", tmp); 587 return -EINVAL; 588 } 589 590 return (trickle_cfg | i); 591 } 592 593 #ifdef CONFIG_WATCHDOG 594 595 static inline u8 timeout_bits(unsigned int timeout) 596 { 597 return ((timeout << ABX8XX_WDT_BMB_SHIFT) & ABX8XX_WDT_BMB_MASK) | 598 ABX8XX_WDT_WRB_1HZ; 599 } 600 601 static int __abx80x_wdog_set_timeout(struct watchdog_device *wdog, 602 unsigned int timeout) 603 { 604 struct abx80x_priv *priv = watchdog_get_drvdata(wdog); 605 u8 val = ABX8XX_WDT_WDS | timeout_bits(timeout); 606 607 /* 608 * Writing any timeout to the WDT register resets the watchdog timer. 609 * Writing 0 disables it. 610 */ 611 return i2c_smbus_write_byte_data(priv->client, ABX8XX_REG_WDT, val); 612 } 613 614 static int abx80x_wdog_set_timeout(struct watchdog_device *wdog, 615 unsigned int new_timeout) 616 { 617 int err = 0; 618 619 if (watchdog_hw_running(wdog)) 620 err = __abx80x_wdog_set_timeout(wdog, new_timeout); 621 622 if (err == 0) 623 wdog->timeout = new_timeout; 624 625 return err; 626 } 627 628 static int abx80x_wdog_ping(struct watchdog_device *wdog) 629 { 630 return __abx80x_wdog_set_timeout(wdog, wdog->timeout); 631 } 632 633 static int abx80x_wdog_start(struct watchdog_device *wdog) 634 { 635 return __abx80x_wdog_set_timeout(wdog, wdog->timeout); 636 } 637 638 static int abx80x_wdog_stop(struct watchdog_device *wdog) 639 { 640 return __abx80x_wdog_set_timeout(wdog, 0); 641 } 642 643 static const struct watchdog_info abx80x_wdog_info = { 644 .identity = "abx80x watchdog", 645 .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, 646 }; 647 648 static const struct watchdog_ops abx80x_wdog_ops = { 649 .owner = THIS_MODULE, 650 .start = abx80x_wdog_start, 651 .stop = abx80x_wdog_stop, 652 .ping = abx80x_wdog_ping, 653 .set_timeout = abx80x_wdog_set_timeout, 654 }; 655 656 static int abx80x_setup_watchdog(struct abx80x_priv *priv) 657 { 658 priv->wdog.parent = &priv->client->dev; 659 priv->wdog.ops = &abx80x_wdog_ops; 660 priv->wdog.info = &abx80x_wdog_info; 661 priv->wdog.min_timeout = 1; 662 priv->wdog.max_timeout = ABX8XX_WDT_MAX_TIME; 663 priv->wdog.timeout = ABX8XX_WDT_MAX_TIME; 664 665 watchdog_set_drvdata(&priv->wdog, priv); 666 667 return devm_watchdog_register_device(&priv->client->dev, &priv->wdog); 668 } 669 #else 670 static int abx80x_setup_watchdog(struct abx80x_priv *priv) 671 { 672 return 0; 673 } 674 #endif 675 676 static int abx80x_probe(struct i2c_client *client, 677 const struct i2c_device_id *id) 678 { 679 struct device_node *np = client->dev.of_node; 680 struct abx80x_priv *priv; 681 int i, data, err, trickle_cfg = -EINVAL; 682 char buf[7]; 683 unsigned int part = id->driver_data; 684 unsigned int partnumber; 685 unsigned int majrev, minrev; 686 unsigned int lot; 687 unsigned int wafer; 688 unsigned int uid; 689 690 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) 691 return -ENODEV; 692 693 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ID0, 694 sizeof(buf), buf); 695 if (err < 0) { 696 dev_err(&client->dev, "Unable to read partnumber\n"); 697 return -EIO; 698 } 699 700 partnumber = (buf[0] << 8) | buf[1]; 701 majrev = buf[2] >> 3; 702 minrev = buf[2] & 0x7; 703 lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3]; 704 uid = ((buf[4] & 0x7f) << 8) | buf[5]; 705 wafer = (buf[6] & 0x7c) >> 2; 706 dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n", 707 partnumber, majrev, minrev, lot, wafer, uid); 708 709 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL1); 710 if (data < 0) { 711 dev_err(&client->dev, "Unable to read control register\n"); 712 return -EIO; 713 } 714 715 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1, 716 ((data & ~(ABX8XX_CTRL_12_24 | 717 ABX8XX_CTRL_ARST)) | 718 ABX8XX_CTRL_WRITE)); 719 if (err < 0) { 720 dev_err(&client->dev, "Unable to write control register\n"); 721 return -EIO; 722 } 723 724 /* Configure RV1805 specifics */ 725 if (part == RV1805) { 726 /* 727 * Avoid accidentally entering test mode. This can happen 728 * on the RV1805 in case the reserved bit 5 in control2 729 * register is set. RV-1805-C3 datasheet indicates that 730 * the bit should be cleared in section 11h - Control2. 731 */ 732 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL2); 733 if (data < 0) { 734 dev_err(&client->dev, 735 "Unable to read control2 register\n"); 736 return -EIO; 737 } 738 739 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL2, 740 data & ~ABX8XX_CTRL2_RSVD); 741 if (err < 0) { 742 dev_err(&client->dev, 743 "Unable to write control2 register\n"); 744 return -EIO; 745 } 746 747 /* 748 * Avoid extra power leakage. The RV1805 uses smaller 749 * 10pin package and the EXTI input is not present. 750 * Disable it to avoid leakage. 751 */ 752 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_OUT_CTRL); 753 if (data < 0) { 754 dev_err(&client->dev, 755 "Unable to read output control register\n"); 756 return -EIO; 757 } 758 759 /* 760 * Write the configuration key register to enable access to 761 * the config2 register 762 */ 763 if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_MISC) < 0) 764 return -EIO; 765 766 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OUT_CTRL, 767 data | ABX8XX_OUT_CTRL_EXDS); 768 if (err < 0) { 769 dev_err(&client->dev, 770 "Unable to write output control register\n"); 771 return -EIO; 772 } 773 } 774 775 /* part autodetection */ 776 if (part == ABX80X) { 777 for (i = 0; abx80x_caps[i].pn; i++) 778 if (partnumber == abx80x_caps[i].pn) 779 break; 780 if (abx80x_caps[i].pn == 0) { 781 dev_err(&client->dev, "Unknown part: %04x\n", 782 partnumber); 783 return -EINVAL; 784 } 785 part = i; 786 } 787 788 if (partnumber != abx80x_caps[part].pn) { 789 dev_err(&client->dev, "partnumber mismatch %04x != %04x\n", 790 partnumber, abx80x_caps[part].pn); 791 return -EINVAL; 792 } 793 794 if (np && abx80x_caps[part].has_tc) 795 trickle_cfg = abx80x_dt_trickle_cfg(client); 796 797 if (trickle_cfg > 0) { 798 dev_info(&client->dev, "Enabling trickle charger: %02x\n", 799 trickle_cfg); 800 abx80x_enable_trickle_charger(client, trickle_cfg); 801 } 802 803 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL, 804 BIT(2)); 805 if (err) 806 return err; 807 808 priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL); 809 if (priv == NULL) 810 return -ENOMEM; 811 812 priv->rtc = devm_rtc_allocate_device(&client->dev); 813 if (IS_ERR(priv->rtc)) 814 return PTR_ERR(priv->rtc); 815 816 priv->rtc->ops = &abx80x_rtc_ops; 817 priv->client = client; 818 819 i2c_set_clientdata(client, priv); 820 821 if (abx80x_caps[part].has_wdog) { 822 err = abx80x_setup_watchdog(priv); 823 if (err) 824 return err; 825 } 826 827 if (client->irq > 0) { 828 dev_info(&client->dev, "IRQ %d supplied\n", client->irq); 829 err = devm_request_threaded_irq(&client->dev, client->irq, NULL, 830 abx80x_handle_irq, 831 IRQF_SHARED | IRQF_ONESHOT, 832 "abx8xx", 833 client); 834 if (err) { 835 dev_err(&client->dev, "unable to request IRQ, alarms disabled\n"); 836 client->irq = 0; 837 } 838 } 839 840 err = rtc_add_group(priv->rtc, &rtc_calib_attr_group); 841 if (err) { 842 dev_err(&client->dev, "Failed to create sysfs group: %d\n", 843 err); 844 return err; 845 } 846 847 return devm_rtc_register_device(priv->rtc); 848 } 849 850 static const struct i2c_device_id abx80x_id[] = { 851 { "abx80x", ABX80X }, 852 { "ab0801", AB0801 }, 853 { "ab0803", AB0803 }, 854 { "ab0804", AB0804 }, 855 { "ab0805", AB0805 }, 856 { "ab1801", AB1801 }, 857 { "ab1803", AB1803 }, 858 { "ab1804", AB1804 }, 859 { "ab1805", AB1805 }, 860 { "rv1805", RV1805 }, 861 { } 862 }; 863 MODULE_DEVICE_TABLE(i2c, abx80x_id); 864 865 #ifdef CONFIG_OF 866 static const struct of_device_id abx80x_of_match[] = { 867 { 868 .compatible = "abracon,abx80x", 869 .data = (void *)ABX80X 870 }, 871 { 872 .compatible = "abracon,ab0801", 873 .data = (void *)AB0801 874 }, 875 { 876 .compatible = "abracon,ab0803", 877 .data = (void *)AB0803 878 }, 879 { 880 .compatible = "abracon,ab0804", 881 .data = (void *)AB0804 882 }, 883 { 884 .compatible = "abracon,ab0805", 885 .data = (void *)AB0805 886 }, 887 { 888 .compatible = "abracon,ab1801", 889 .data = (void *)AB1801 890 }, 891 { 892 .compatible = "abracon,ab1803", 893 .data = (void *)AB1803 894 }, 895 { 896 .compatible = "abracon,ab1804", 897 .data = (void *)AB1804 898 }, 899 { 900 .compatible = "abracon,ab1805", 901 .data = (void *)AB1805 902 }, 903 { 904 .compatible = "microcrystal,rv1805", 905 .data = (void *)RV1805 906 }, 907 { } 908 }; 909 MODULE_DEVICE_TABLE(of, abx80x_of_match); 910 #endif 911 912 static struct i2c_driver abx80x_driver = { 913 .driver = { 914 .name = "rtc-abx80x", 915 .of_match_table = of_match_ptr(abx80x_of_match), 916 }, 917 .probe = abx80x_probe, 918 .id_table = abx80x_id, 919 }; 920 921 module_i2c_driver(abx80x_driver); 922 923 MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>"); 924 MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>"); 925 MODULE_DESCRIPTION("Abracon ABX80X RTC driver"); 926 MODULE_LICENSE("GPL v2"); 927