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1// SPDX-License-Identifier: GPL-2.02/*3 * A driver for the I2C members of the Abracon AB x8xx RTC family,4 * and compatible: AB 1805 and AB 08055 *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/bitfield.h>15#include <linux/i2c.h>16#include <linux/kstrtox.h>17#include <linux/module.h>18#include <linux/of.h>19#include <linux/rtc.h>20#include <linux/watchdog.h>21 22#define ABX8XX_REG_HTH 0x0023#define ABX8XX_REG_SC 0x0124#define ABX8XX_REG_MN 0x0225#define ABX8XX_REG_HR 0x0326#define ABX8XX_REG_DA 0x0427#define ABX8XX_REG_MO 0x0528#define ABX8XX_REG_YR 0x0629#define ABX8XX_REG_WD 0x0730 31#define ABX8XX_REG_AHTH 0x0832#define ABX8XX_REG_ASC 0x0933#define ABX8XX_REG_AMN 0x0a34#define ABX8XX_REG_AHR 0x0b35#define ABX8XX_REG_ADA 0x0c36#define ABX8XX_REG_AMO 0x0d37#define ABX8XX_REG_AWD 0x0e38 39#define ABX8XX_REG_STATUS 0x0f40#define ABX8XX_STATUS_AF BIT(2)41#define ABX8XX_STATUS_BLF BIT(4)42#define ABX8XX_STATUS_WDT BIT(6)43 44#define ABX8XX_REG_CTRL1 0x1045#define ABX8XX_CTRL_WRITE BIT(0)46#define ABX8XX_CTRL_ARST BIT(2)47#define ABX8XX_CTRL_12_24 BIT(6)48 49#define ABX8XX_REG_CTRL2 0x1150#define ABX8XX_CTRL2_RSVD BIT(5)51 52#define ABX8XX_REG_IRQ 0x1253#define ABX8XX_IRQ_AIE BIT(2)54#define ABX8XX_IRQ_IM_1_4 (0x3 << 5)55 56#define ABX8XX_REG_CD_TIMER_CTL 0x1857 58#define ABX8XX_REG_OSC 0x1c59#define ABX8XX_OSC_FOS BIT(3)60#define ABX8XX_OSC_BOS BIT(4)61#define ABX8XX_OSC_ACAL_512 BIT(5)62#define ABX8XX_OSC_ACAL_1024 BIT(6)63 64#define ABX8XX_OSC_OSEL BIT(7)65 66#define ABX8XX_REG_OSS 0x1d67#define ABX8XX_OSS_OF BIT(1)68#define ABX8XX_OSS_OMODE BIT(4)69 70#define ABX8XX_REG_WDT 0x1b71#define ABX8XX_WDT_WDS BIT(7)72#define ABX8XX_WDT_BMB_MASK 0x7c73#define ABX8XX_WDT_BMB_SHIFT 274#define ABX8XX_WDT_MAX_TIME (ABX8XX_WDT_BMB_MASK >> ABX8XX_WDT_BMB_SHIFT)75#define ABX8XX_WDT_WRB_MASK 0x0376#define ABX8XX_WDT_WRB_1HZ 0x0277 78#define ABX8XX_REG_CFG_KEY 0x1f79#define ABX8XX_CFG_KEY_OSC 0xa180#define ABX8XX_CFG_KEY_MISC 0x9d81 82#define ABX8XX_REG_ID0 0x2883 84#define ABX8XX_REG_OUT_CTRL 0x3085#define ABX8XX_OUT_CTRL_EXDS BIT(4)86 87#define ABX8XX_REG_TRICKLE 0x2088#define ABX8XX_TRICKLE_CHARGE_ENABLE 0xa089#define ABX8XX_TRICKLE_STANDARD_DIODE 0x890#define ABX8XX_TRICKLE_SCHOTTKY_DIODE 0x491 92#define ABX8XX_REG_EXTRAM 0x3f93#define ABX8XX_EXTRAM_XADS GENMASK(1, 0)94 95#define ABX8XX_SRAM_BASE 0x4096#define ABX8XX_SRAM_WIN_SIZE 0x4097#define ABX8XX_RAM_SIZE 25698 99#define NVMEM_ADDR_LOWER GENMASK(5, 0)100#define NVMEM_ADDR_UPPER GENMASK(7, 6)101 102static u8 trickle_resistors[] = {0, 3, 6, 11};103 104enum abx80x_chip {AB0801, AB0803, AB0804, AB0805,105 AB1801, AB1803, AB1804, AB1805, RV1805, ABX80X};106 107struct abx80x_cap {108 u16 pn;109 bool has_tc;110 bool has_wdog;111};112 113static struct abx80x_cap abx80x_caps[] = {114 [AB0801] = {.pn = 0x0801},115 [AB0803] = {.pn = 0x0803},116 [AB0804] = {.pn = 0x0804, .has_tc = true, .has_wdog = true},117 [AB0805] = {.pn = 0x0805, .has_tc = true, .has_wdog = true},118 [AB1801] = {.pn = 0x1801},119 [AB1803] = {.pn = 0x1803},120 [AB1804] = {.pn = 0x1804, .has_tc = true, .has_wdog = true},121 [AB1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true},122 [RV1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true},123 [ABX80X] = {.pn = 0}124};125 126struct abx80x_priv {127 struct rtc_device *rtc;128 struct i2c_client *client;129 struct watchdog_device wdog;130};131 132static int abx80x_write_config_key(struct i2c_client *client, u8 key)133{134 if (i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY, key) < 0) {135 dev_err(&client->dev, "Unable to write configuration key\n");136 return -EIO;137 }138 139 return 0;140}141 142static int abx80x_is_rc_mode(struct i2c_client *client)143{144 int flags = 0;145 146 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);147 if (flags < 0) {148 dev_err(&client->dev,149 "Failed to read autocalibration attribute\n");150 return flags;151 }152 153 return (flags & ABX8XX_OSS_OMODE) ? 1 : 0;154}155 156static int abx80x_enable_trickle_charger(struct i2c_client *client,157 u8 trickle_cfg)158{159 int err;160 161 /*162 * Write the configuration key register to enable access to the Trickle163 * register164 */165 if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_MISC) < 0)166 return -EIO;167 168 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_TRICKLE,169 ABX8XX_TRICKLE_CHARGE_ENABLE |170 trickle_cfg);171 if (err < 0) {172 dev_err(&client->dev, "Unable to write trickle register\n");173 return -EIO;174 }175 176 return 0;177}178 179static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm)180{181 struct i2c_client *client = to_i2c_client(dev);182 unsigned char buf[8];183 int err, flags, rc_mode = 0;184 185 /* Read the Oscillator Failure only in XT mode */186 rc_mode = abx80x_is_rc_mode(client);187 if (rc_mode < 0)188 return rc_mode;189 190 if (!rc_mode) {191 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);192 if (flags < 0)193 return flags;194 195 if (flags & ABX8XX_OSS_OF) {196 dev_err(dev, "Oscillator failure, data is invalid.\n");197 return -EINVAL;198 }199 }200 201 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH,202 sizeof(buf), buf);203 if (err < 0) {204 dev_err(&client->dev, "Unable to read date\n");205 return -EIO;206 }207 208 tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F);209 tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F);210 tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F);211 tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7;212 tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F);213 tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F) - 1;214 tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 100;215 216 return 0;217}218 219static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm)220{221 struct i2c_client *client = to_i2c_client(dev);222 unsigned char buf[8];223 int err, flags;224 225 if (tm->tm_year < 100)226 return -EINVAL;227 228 buf[ABX8XX_REG_HTH] = 0;229 buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec);230 buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min);231 buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour);232 buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday);233 buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon + 1);234 buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 100);235 buf[ABX8XX_REG_WD] = tm->tm_wday;236 237 err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_HTH,238 sizeof(buf), buf);239 if (err < 0) {240 dev_err(&client->dev, "Unable to write to date registers\n");241 return -EIO;242 }243 244 /* Clear the OF bit of Oscillator Status Register */245 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);246 if (flags < 0)247 return flags;248 249 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSS,250 flags & ~ABX8XX_OSS_OF);251 if (err < 0) {252 dev_err(&client->dev, "Unable to write oscillator status register\n");253 return err;254 }255 256 return 0;257}258 259static irqreturn_t abx80x_handle_irq(int irq, void *dev_id)260{261 struct i2c_client *client = dev_id;262 struct abx80x_priv *priv = i2c_get_clientdata(client);263 struct rtc_device *rtc = priv->rtc;264 int status;265 266 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);267 if (status < 0)268 return IRQ_NONE;269 270 if (status & ABX8XX_STATUS_AF)271 rtc_update_irq(rtc, 1, RTC_AF | RTC_IRQF);272 273 /*274 * It is unclear if we'll get an interrupt before the external275 * reset kicks in.276 */277 if (status & ABX8XX_STATUS_WDT)278 dev_alert(&client->dev, "watchdog timeout interrupt.\n");279 280 i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);281 282 return IRQ_HANDLED;283}284 285static int abx80x_read_alarm(struct device *dev, struct rtc_wkalrm *t)286{287 struct i2c_client *client = to_i2c_client(dev);288 unsigned char buf[7];289 290 int irq_mask, err;291 292 if (client->irq <= 0)293 return -EINVAL;294 295 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC,296 sizeof(buf), buf);297 if (err)298 return err;299 300 irq_mask = i2c_smbus_read_byte_data(client, ABX8XX_REG_IRQ);301 if (irq_mask < 0)302 return irq_mask;303 304 t->time.tm_sec = bcd2bin(buf[0] & 0x7F);305 t->time.tm_min = bcd2bin(buf[1] & 0x7F);306 t->time.tm_hour = bcd2bin(buf[2] & 0x3F);307 t->time.tm_mday = bcd2bin(buf[3] & 0x3F);308 t->time.tm_mon = bcd2bin(buf[4] & 0x1F) - 1;309 t->time.tm_wday = buf[5] & 0x7;310 311 t->enabled = !!(irq_mask & ABX8XX_IRQ_AIE);312 t->pending = (buf[6] & ABX8XX_STATUS_AF) && t->enabled;313 314 return err;315}316 317static int abx80x_set_alarm(struct device *dev, struct rtc_wkalrm *t)318{319 struct i2c_client *client = to_i2c_client(dev);320 u8 alarm[6];321 int err;322 323 if (client->irq <= 0)324 return -EINVAL;325 326 alarm[0] = 0x0;327 alarm[1] = bin2bcd(t->time.tm_sec);328 alarm[2] = bin2bcd(t->time.tm_min);329 alarm[3] = bin2bcd(t->time.tm_hour);330 alarm[4] = bin2bcd(t->time.tm_mday);331 alarm[5] = bin2bcd(t->time.tm_mon + 1);332 333 err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_AHTH,334 sizeof(alarm), alarm);335 if (err < 0) {336 dev_err(&client->dev, "Unable to write alarm registers\n");337 return -EIO;338 }339 340 if (t->enabled) {341 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,342 (ABX8XX_IRQ_IM_1_4 |343 ABX8XX_IRQ_AIE));344 if (err)345 return err;346 }347 348 return 0;349}350 351static int abx80x_rtc_set_autocalibration(struct device *dev,352 int autocalibration)353{354 struct i2c_client *client = to_i2c_client(dev);355 int retval, flags = 0;356 357 if ((autocalibration != 0) && (autocalibration != 1024) &&358 (autocalibration != 512)) {359 dev_err(dev, "autocalibration value outside permitted range\n");360 return -EINVAL;361 }362 363 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);364 if (flags < 0)365 return flags;366 367 if (autocalibration == 0) {368 flags &= ~(ABX8XX_OSC_ACAL_512 | ABX8XX_OSC_ACAL_1024);369 } else if (autocalibration == 1024) {370 /* 1024 autocalibration is 0x10 */371 flags |= ABX8XX_OSC_ACAL_1024;372 flags &= ~(ABX8XX_OSC_ACAL_512);373 } else {374 /* 512 autocalibration is 0x11 */375 flags |= (ABX8XX_OSC_ACAL_1024 | ABX8XX_OSC_ACAL_512);376 }377 378 /* Unlock write access to Oscillator Control Register */379 if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_OSC) < 0)380 return -EIO;381 382 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags);383 384 return retval;385}386 387static int abx80x_rtc_get_autocalibration(struct device *dev)388{389 struct i2c_client *client = to_i2c_client(dev);390 int flags = 0, autocalibration;391 392 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);393 if (flags < 0)394 return flags;395 396 if (flags & ABX8XX_OSC_ACAL_512)397 autocalibration = 512;398 else if (flags & ABX8XX_OSC_ACAL_1024)399 autocalibration = 1024;400 else401 autocalibration = 0;402 403 return autocalibration;404}405 406static ssize_t autocalibration_store(struct device *dev,407 struct device_attribute *attr,408 const char *buf, size_t count)409{410 int retval;411 unsigned long autocalibration = 0;412 413 retval = kstrtoul(buf, 10, &autocalibration);414 if (retval < 0) {415 dev_err(dev, "Failed to store RTC autocalibration attribute\n");416 return -EINVAL;417 }418 419 retval = abx80x_rtc_set_autocalibration(dev->parent, autocalibration);420 421 return retval ? retval : count;422}423 424static ssize_t autocalibration_show(struct device *dev,425 struct device_attribute *attr, char *buf)426{427 int autocalibration = 0;428 429 autocalibration = abx80x_rtc_get_autocalibration(dev->parent);430 if (autocalibration < 0) {431 dev_err(dev, "Failed to read RTC autocalibration\n");432 sprintf(buf, "0\n");433 return autocalibration;434 }435 436 return sprintf(buf, "%d\n", autocalibration);437}438 439static DEVICE_ATTR_RW(autocalibration);440 441static ssize_t oscillator_store(struct device *dev,442 struct device_attribute *attr,443 const char *buf, size_t count)444{445 struct i2c_client *client = to_i2c_client(dev->parent);446 int retval, flags, rc_mode = 0;447 448 if (strncmp(buf, "rc", 2) == 0) {449 rc_mode = 1;450 } else if (strncmp(buf, "xtal", 4) == 0) {451 rc_mode = 0;452 } else {453 dev_err(dev, "Oscillator selection value outside permitted ones\n");454 return -EINVAL;455 }456 457 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);458 if (flags < 0)459 return flags;460 461 if (rc_mode == 0)462 flags &= ~(ABX8XX_OSC_OSEL);463 else464 flags |= (ABX8XX_OSC_OSEL);465 466 /* Unlock write access on Oscillator Control register */467 if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_OSC) < 0)468 return -EIO;469 470 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags);471 if (retval < 0) {472 dev_err(dev, "Failed to write Oscillator Control register\n");473 return retval;474 }475 476 return retval ? retval : count;477}478 479static ssize_t oscillator_show(struct device *dev,480 struct device_attribute *attr, char *buf)481{482 int rc_mode = 0;483 struct i2c_client *client = to_i2c_client(dev->parent);484 485 rc_mode = abx80x_is_rc_mode(client);486 487 if (rc_mode < 0) {488 dev_err(dev, "Failed to read RTC oscillator selection\n");489 sprintf(buf, "\n");490 return rc_mode;491 }492 493 if (rc_mode)494 return sprintf(buf, "rc\n");495 else496 return sprintf(buf, "xtal\n");497}498 499static DEVICE_ATTR_RW(oscillator);500 501static struct attribute *rtc_calib_attrs[] = {502 &dev_attr_autocalibration.attr,503 &dev_attr_oscillator.attr,504 NULL,505};506 507static const struct attribute_group rtc_calib_attr_group = {508 .attrs = rtc_calib_attrs,509};510 511static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled)512{513 struct i2c_client *client = to_i2c_client(dev);514 int err;515 516 if (enabled)517 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,518 (ABX8XX_IRQ_IM_1_4 |519 ABX8XX_IRQ_AIE));520 else521 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,522 ABX8XX_IRQ_IM_1_4);523 return err;524}525 526static int abx80x_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)527{528 struct i2c_client *client = to_i2c_client(dev);529 int status, tmp;530 531 switch (cmd) {532 case RTC_VL_READ:533 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);534 if (status < 0)535 return status;536 537 tmp = status & ABX8XX_STATUS_BLF ? RTC_VL_BACKUP_LOW : 0;538 539 return put_user(tmp, (unsigned int __user *)arg);540 541 case RTC_VL_CLR:542 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);543 if (status < 0)544 return status;545 546 status &= ~ABX8XX_STATUS_BLF;547 548 tmp = i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);549 if (tmp < 0)550 return tmp;551 552 return 0;553 554 default:555 return -ENOIOCTLCMD;556 }557}558 559static const struct rtc_class_ops abx80x_rtc_ops = {560 .read_time = abx80x_rtc_read_time,561 .set_time = abx80x_rtc_set_time,562 .read_alarm = abx80x_read_alarm,563 .set_alarm = abx80x_set_alarm,564 .alarm_irq_enable = abx80x_alarm_irq_enable,565 .ioctl = abx80x_ioctl,566};567 568static int abx80x_dt_trickle_cfg(struct i2c_client *client)569{570 struct device_node *np = client->dev.of_node;571 const char *diode;572 int trickle_cfg = 0;573 int i, ret;574 u32 tmp;575 576 ret = of_property_read_string(np, "abracon,tc-diode", &diode);577 if (ret)578 return ret;579 580 if (!strcmp(diode, "standard")) {581 trickle_cfg |= ABX8XX_TRICKLE_STANDARD_DIODE;582 } else if (!strcmp(diode, "schottky")) {583 trickle_cfg |= ABX8XX_TRICKLE_SCHOTTKY_DIODE;584 } else {585 dev_dbg(&client->dev, "Invalid tc-diode value: %s\n", diode);586 return -EINVAL;587 }588 589 ret = of_property_read_u32(np, "abracon,tc-resistor", &tmp);590 if (ret)591 return ret;592 593 for (i = 0; i < sizeof(trickle_resistors); i++)594 if (trickle_resistors[i] == tmp)595 break;596 597 if (i == sizeof(trickle_resistors)) {598 dev_dbg(&client->dev, "Invalid tc-resistor value: %u\n", tmp);599 return -EINVAL;600 }601 602 return (trickle_cfg | i);603}604 605#ifdef CONFIG_WATCHDOG606 607static inline u8 timeout_bits(unsigned int timeout)608{609 return ((timeout << ABX8XX_WDT_BMB_SHIFT) & ABX8XX_WDT_BMB_MASK) |610 ABX8XX_WDT_WRB_1HZ;611}612 613static int __abx80x_wdog_set_timeout(struct watchdog_device *wdog,614 unsigned int timeout)615{616 struct abx80x_priv *priv = watchdog_get_drvdata(wdog);617 u8 val = ABX8XX_WDT_WDS | timeout_bits(timeout);618 619 /*620 * Writing any timeout to the WDT register resets the watchdog timer.621 * Writing 0 disables it.622 */623 return i2c_smbus_write_byte_data(priv->client, ABX8XX_REG_WDT, val);624}625 626static int abx80x_wdog_set_timeout(struct watchdog_device *wdog,627 unsigned int new_timeout)628{629 int err = 0;630 631 if (watchdog_hw_running(wdog))632 err = __abx80x_wdog_set_timeout(wdog, new_timeout);633 634 if (err == 0)635 wdog->timeout = new_timeout;636 637 return err;638}639 640static int abx80x_wdog_ping(struct watchdog_device *wdog)641{642 return __abx80x_wdog_set_timeout(wdog, wdog->timeout);643}644 645static int abx80x_wdog_start(struct watchdog_device *wdog)646{647 return __abx80x_wdog_set_timeout(wdog, wdog->timeout);648}649 650static int abx80x_wdog_stop(struct watchdog_device *wdog)651{652 return __abx80x_wdog_set_timeout(wdog, 0);653}654 655static const struct watchdog_info abx80x_wdog_info = {656 .identity = "abx80x watchdog",657 .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,658};659 660static const struct watchdog_ops abx80x_wdog_ops = {661 .owner = THIS_MODULE,662 .start = abx80x_wdog_start,663 .stop = abx80x_wdog_stop,664 .ping = abx80x_wdog_ping,665 .set_timeout = abx80x_wdog_set_timeout,666};667 668static int abx80x_setup_watchdog(struct abx80x_priv *priv)669{670 priv->wdog.parent = &priv->client->dev;671 priv->wdog.ops = &abx80x_wdog_ops;672 priv->wdog.info = &abx80x_wdog_info;673 priv->wdog.min_timeout = 1;674 priv->wdog.max_timeout = ABX8XX_WDT_MAX_TIME;675 priv->wdog.timeout = ABX8XX_WDT_MAX_TIME;676 677 watchdog_set_drvdata(&priv->wdog, priv);678 679 return devm_watchdog_register_device(&priv->client->dev, &priv->wdog);680}681#else682static int abx80x_setup_watchdog(struct abx80x_priv *priv)683{684 return 0;685}686#endif687 688static int abx80x_nvmem_xfer(struct abx80x_priv *priv, unsigned int offset,689 void *val, size_t bytes, bool write)690{691 int ret;692 693 while (bytes) {694 u8 extram, reg, len, lower, upper;695 696 lower = FIELD_GET(NVMEM_ADDR_LOWER, offset);697 upper = FIELD_GET(NVMEM_ADDR_UPPER, offset);698 extram = FIELD_PREP(ABX8XX_EXTRAM_XADS, upper);699 reg = ABX8XX_SRAM_BASE + lower;700 len = min(lower + bytes, (size_t)ABX8XX_SRAM_WIN_SIZE) - lower;701 len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX);702 703 ret = i2c_smbus_write_byte_data(priv->client, ABX8XX_REG_EXTRAM,704 extram);705 if (ret)706 return ret;707 708 if (write) {709 ret = i2c_smbus_write_i2c_block_data(priv->client, reg,710 len, val);711 if (ret)712 return ret;713 } else {714 ret = i2c_smbus_read_i2c_block_data(priv->client, reg,715 len, val);716 if (ret <= 0)717 return ret ? ret : -EIO;718 len = ret;719 }720 721 offset += len;722 val += len;723 bytes -= len;724 }725 726 return 0;727}728 729static int abx80x_nvmem_read(void *priv, unsigned int offset, void *val,730 size_t bytes)731{732 return abx80x_nvmem_xfer(priv, offset, val, bytes, false);733}734 735static int abx80x_nvmem_write(void *priv, unsigned int offset, void *val,736 size_t bytes)737{738 return abx80x_nvmem_xfer(priv, offset, val, bytes, true);739}740 741static int abx80x_setup_nvmem(struct abx80x_priv *priv)742{743 struct nvmem_config config = {744 .type = NVMEM_TYPE_BATTERY_BACKED,745 .reg_read = abx80x_nvmem_read,746 .reg_write = abx80x_nvmem_write,747 .size = ABX8XX_RAM_SIZE,748 .priv = priv,749 };750 751 return devm_rtc_nvmem_register(priv->rtc, &config);752}753 754static const struct i2c_device_id abx80x_id[] = {755 { "abx80x", ABX80X },756 { "ab0801", AB0801 },757 { "ab0803", AB0803 },758 { "ab0804", AB0804 },759 { "ab0805", AB0805 },760 { "ab1801", AB1801 },761 { "ab1803", AB1803 },762 { "ab1804", AB1804 },763 { "ab1805", AB1805 },764 { "rv1805", RV1805 },765 { }766};767MODULE_DEVICE_TABLE(i2c, abx80x_id);768 769static int abx80x_probe(struct i2c_client *client)770{771 struct device_node *np = client->dev.of_node;772 struct abx80x_priv *priv;773 int i, data, err, trickle_cfg = -EINVAL;774 char buf[7];775 const struct i2c_device_id *id = i2c_match_id(abx80x_id, client);776 unsigned int part = id->driver_data;777 unsigned int partnumber;778 unsigned int majrev, minrev;779 unsigned int lot;780 unsigned int wafer;781 unsigned int uid;782 783 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))784 return -ENODEV;785 786 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ID0,787 sizeof(buf), buf);788 if (err < 0) {789 dev_err(&client->dev, "Unable to read partnumber\n");790 return -EIO;791 }792 793 partnumber = (buf[0] << 8) | buf[1];794 majrev = buf[2] >> 3;795 minrev = buf[2] & 0x7;796 lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3];797 uid = ((buf[4] & 0x7f) << 8) | buf[5];798 wafer = (buf[6] & 0x7c) >> 2;799 dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n",800 partnumber, majrev, minrev, lot, wafer, uid);801 802 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL1);803 if (data < 0) {804 dev_err(&client->dev, "Unable to read control register\n");805 return -EIO;806 }807 808 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1,809 ((data & ~(ABX8XX_CTRL_12_24 |810 ABX8XX_CTRL_ARST)) |811 ABX8XX_CTRL_WRITE));812 if (err < 0) {813 dev_err(&client->dev, "Unable to write control register\n");814 return -EIO;815 }816 817 /* Configure RV1805 specifics */818 if (part == RV1805) {819 /*820 * Avoid accidentally entering test mode. This can happen821 * on the RV1805 in case the reserved bit 5 in control2822 * register is set. RV-1805-C3 datasheet indicates that823 * the bit should be cleared in section 11h - Control2.824 */825 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL2);826 if (data < 0) {827 dev_err(&client->dev,828 "Unable to read control2 register\n");829 return -EIO;830 }831 832 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL2,833 data & ~ABX8XX_CTRL2_RSVD);834 if (err < 0) {835 dev_err(&client->dev,836 "Unable to write control2 register\n");837 return -EIO;838 }839 840 /*841 * Avoid extra power leakage. The RV1805 uses smaller842 * 10pin package and the EXTI input is not present.843 * Disable it to avoid leakage.844 */845 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_OUT_CTRL);846 if (data < 0) {847 dev_err(&client->dev,848 "Unable to read output control register\n");849 return -EIO;850 }851 852 /*853 * Write the configuration key register to enable access to854 * the config2 register855 */856 if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_MISC) < 0)857 return -EIO;858 859 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OUT_CTRL,860 data | ABX8XX_OUT_CTRL_EXDS);861 if (err < 0) {862 dev_err(&client->dev,863 "Unable to write output control register\n");864 return -EIO;865 }866 }867 868 /* part autodetection */869 if (part == ABX80X) {870 for (i = 0; abx80x_caps[i].pn; i++)871 if (partnumber == abx80x_caps[i].pn)872 break;873 if (abx80x_caps[i].pn == 0) {874 dev_err(&client->dev, "Unknown part: %04x\n",875 partnumber);876 return -EINVAL;877 }878 part = i;879 }880 881 if (partnumber != abx80x_caps[part].pn) {882 dev_err(&client->dev, "partnumber mismatch %04x != %04x\n",883 partnumber, abx80x_caps[part].pn);884 return -EINVAL;885 }886 887 if (np && abx80x_caps[part].has_tc)888 trickle_cfg = abx80x_dt_trickle_cfg(client);889 890 if (trickle_cfg > 0) {891 dev_info(&client->dev, "Enabling trickle charger: %02x\n",892 trickle_cfg);893 abx80x_enable_trickle_charger(client, trickle_cfg);894 }895 896 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL,897 BIT(2));898 if (err)899 return err;900 901 priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);902 if (priv == NULL)903 return -ENOMEM;904 905 priv->rtc = devm_rtc_allocate_device(&client->dev);906 if (IS_ERR(priv->rtc))907 return PTR_ERR(priv->rtc);908 909 priv->rtc->ops = &abx80x_rtc_ops;910 priv->client = client;911 912 i2c_set_clientdata(client, priv);913 914 if (abx80x_caps[part].has_wdog) {915 err = abx80x_setup_watchdog(priv);916 if (err)917 return err;918 }919 920 err = abx80x_setup_nvmem(priv);921 if (err)922 return err;923 924 if (client->irq > 0) {925 dev_info(&client->dev, "IRQ %d supplied\n", client->irq);926 err = devm_request_threaded_irq(&client->dev, client->irq, NULL,927 abx80x_handle_irq,928 IRQF_SHARED | IRQF_ONESHOT,929 "abx8xx",930 client);931 if (err) {932 dev_err(&client->dev, "unable to request IRQ, alarms disabled\n");933 client->irq = 0;934 }935 }936 937 err = rtc_add_group(priv->rtc, &rtc_calib_attr_group);938 if (err) {939 dev_err(&client->dev, "Failed to create sysfs group: %d\n",940 err);941 return err;942 }943 944 return devm_rtc_register_device(priv->rtc);945}946 947#ifdef CONFIG_OF948static const struct of_device_id abx80x_of_match[] = {949 {950 .compatible = "abracon,abx80x",951 .data = (void *)ABX80X952 },953 {954 .compatible = "abracon,ab0801",955 .data = (void *)AB0801956 },957 {958 .compatible = "abracon,ab0803",959 .data = (void *)AB0803960 },961 {962 .compatible = "abracon,ab0804",963 .data = (void *)AB0804964 },965 {966 .compatible = "abracon,ab0805",967 .data = (void *)AB0805968 },969 {970 .compatible = "abracon,ab1801",971 .data = (void *)AB1801972 },973 {974 .compatible = "abracon,ab1803",975 .data = (void *)AB1803976 },977 {978 .compatible = "abracon,ab1804",979 .data = (void *)AB1804980 },981 {982 .compatible = "abracon,ab1805",983 .data = (void *)AB1805984 },985 {986 .compatible = "microcrystal,rv1805",987 .data = (void *)RV1805988 },989 { }990};991MODULE_DEVICE_TABLE(of, abx80x_of_match);992#endif993 994static struct i2c_driver abx80x_driver = {995 .driver = {996 .name = "rtc-abx80x",997 .of_match_table = of_match_ptr(abx80x_of_match),998 },999 .probe = abx80x_probe,1000 .id_table = abx80x_id,1001};1002 1003module_i2c_driver(abx80x_driver);1004 1005MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>");1006MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");1007MODULE_DESCRIPTION("Abracon ABX80X RTC driver");1008MODULE_LICENSE("GPL v2");1009