Alexandre Belloni | e6e7376 | 2019-02-13 00:21:36 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * RTC driver for the Micro Crystal RV3028 |
| 4 | * |
| 5 | * Copyright (C) 2019 Micro Crystal SA |
| 6 | * |
| 7 | * Alexandre Belloni <alexandre.belloni@bootlin.com> |
| 8 | * |
| 9 | */ |
| 10 | |
| 11 | #include <linux/bcd.h> |
| 12 | #include <linux/bitops.h> |
| 13 | #include <linux/i2c.h> |
| 14 | #include <linux/interrupt.h> |
| 15 | #include <linux/kernel.h> |
| 16 | #include <linux/log2.h> |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/of_device.h> |
| 19 | #include <linux/regmap.h> |
| 20 | #include <linux/rtc.h> |
| 21 | |
| 22 | #define RV3028_SEC 0x00 |
| 23 | #define RV3028_MIN 0x01 |
| 24 | #define RV3028_HOUR 0x02 |
| 25 | #define RV3028_WDAY 0x03 |
| 26 | #define RV3028_DAY 0x04 |
| 27 | #define RV3028_MONTH 0x05 |
| 28 | #define RV3028_YEAR 0x06 |
| 29 | #define RV3028_ALARM_MIN 0x07 |
| 30 | #define RV3028_ALARM_HOUR 0x08 |
| 31 | #define RV3028_ALARM_DAY 0x09 |
| 32 | #define RV3028_STATUS 0x0E |
| 33 | #define RV3028_CTRL1 0x0F |
| 34 | #define RV3028_CTRL2 0x10 |
| 35 | #define RV3028_EVT_CTRL 0x13 |
| 36 | #define RV3028_TS_COUNT 0x14 |
| 37 | #define RV3028_TS_SEC 0x15 |
| 38 | #define RV3028_RAM1 0x1F |
| 39 | #define RV3028_EEPROM_ADDR 0x25 |
| 40 | #define RV3028_EEPROM_DATA 0x26 |
| 41 | #define RV3028_EEPROM_CMD 0x27 |
| 42 | #define RV3028_CLKOUT 0x35 |
| 43 | #define RV3028_OFFSET 0x36 |
| 44 | #define RV3028_BACKUP 0x37 |
| 45 | |
| 46 | #define RV3028_STATUS_PORF BIT(0) |
| 47 | #define RV3028_STATUS_EVF BIT(1) |
| 48 | #define RV3028_STATUS_AF BIT(2) |
| 49 | #define RV3028_STATUS_TF BIT(3) |
| 50 | #define RV3028_STATUS_UF BIT(4) |
| 51 | #define RV3028_STATUS_BSF BIT(5) |
| 52 | #define RV3028_STATUS_CLKF BIT(6) |
| 53 | #define RV3028_STATUS_EEBUSY BIT(7) |
| 54 | |
| 55 | #define RV3028_CTRL1_EERD BIT(3) |
| 56 | #define RV3028_CTRL1_WADA BIT(5) |
| 57 | |
| 58 | #define RV3028_CTRL2_RESET BIT(0) |
| 59 | #define RV3028_CTRL2_12_24 BIT(1) |
| 60 | #define RV3028_CTRL2_EIE BIT(2) |
| 61 | #define RV3028_CTRL2_AIE BIT(3) |
| 62 | #define RV3028_CTRL2_TIE BIT(4) |
| 63 | #define RV3028_CTRL2_UIE BIT(5) |
| 64 | #define RV3028_CTRL2_TSE BIT(7) |
| 65 | |
| 66 | #define RV3028_EVT_CTRL_TSR BIT(2) |
| 67 | |
| 68 | #define RV3028_EEPROM_CMD_WRITE 0x21 |
| 69 | #define RV3028_EEPROM_CMD_READ 0x22 |
| 70 | |
| 71 | #define RV3028_EEBUSY_POLL 10000 |
| 72 | #define RV3028_EEBUSY_TIMEOUT 100000 |
| 73 | |
| 74 | #define RV3028_BACKUP_TCE BIT(5) |
| 75 | #define RV3028_BACKUP_TCR_MASK GENMASK(1,0) |
| 76 | |
| 77 | #define OFFSET_STEP_PPT 953674 |
| 78 | |
| 79 | enum rv3028_type { |
| 80 | rv_3028, |
| 81 | }; |
| 82 | |
| 83 | struct rv3028_data { |
| 84 | struct regmap *regmap; |
| 85 | struct rtc_device *rtc; |
| 86 | enum rv3028_type type; |
| 87 | }; |
| 88 | |
| 89 | static u16 rv3028_trickle_resistors[] = {1000, 3000, 6000, 11000}; |
| 90 | |
| 91 | static ssize_t timestamp0_store(struct device *dev, |
| 92 | struct device_attribute *attr, |
| 93 | const char *buf, size_t count) |
| 94 | { |
| 95 | struct rv3028_data *rv3028 = dev_get_drvdata(dev->parent); |
| 96 | |
| 97 | regmap_update_bits(rv3028->regmap, RV3028_EVT_CTRL, RV3028_EVT_CTRL_TSR, |
| 98 | RV3028_EVT_CTRL_TSR); |
| 99 | |
| 100 | return count; |
| 101 | }; |
| 102 | |
| 103 | static ssize_t timestamp0_show(struct device *dev, |
| 104 | struct device_attribute *attr, char *buf) |
| 105 | { |
| 106 | struct rv3028_data *rv3028 = dev_get_drvdata(dev->parent); |
| 107 | struct rtc_time tm; |
| 108 | int ret, count; |
| 109 | u8 date[6]; |
| 110 | |
| 111 | ret = regmap_read(rv3028->regmap, RV3028_TS_COUNT, &count); |
| 112 | if (ret) |
| 113 | return ret; |
| 114 | |
| 115 | if (!count) |
| 116 | return 0; |
| 117 | |
| 118 | ret = regmap_bulk_read(rv3028->regmap, RV3028_TS_SEC, date, |
| 119 | sizeof(date)); |
| 120 | if (ret) |
| 121 | return ret; |
| 122 | |
| 123 | tm.tm_sec = bcd2bin(date[0]); |
| 124 | tm.tm_min = bcd2bin(date[1]); |
| 125 | tm.tm_hour = bcd2bin(date[2]); |
| 126 | tm.tm_mday = bcd2bin(date[3]); |
| 127 | tm.tm_mon = bcd2bin(date[4]) - 1; |
| 128 | tm.tm_year = bcd2bin(date[5]) + 100; |
| 129 | |
| 130 | ret = rtc_valid_tm(&tm); |
| 131 | if (ret) |
| 132 | return ret; |
| 133 | |
| 134 | return sprintf(buf, "%llu\n", |
| 135 | (unsigned long long)rtc_tm_to_time64(&tm)); |
| 136 | }; |
| 137 | |
| 138 | static DEVICE_ATTR_RW(timestamp0); |
| 139 | |
| 140 | static ssize_t timestamp0_count_show(struct device *dev, |
| 141 | struct device_attribute *attr, char *buf) |
| 142 | { |
| 143 | struct rv3028_data *rv3028 = dev_get_drvdata(dev->parent); |
| 144 | int ret, count; |
| 145 | |
| 146 | ret = regmap_read(rv3028->regmap, RV3028_TS_COUNT, &count); |
| 147 | if (ret) |
| 148 | return ret; |
| 149 | |
| 150 | return sprintf(buf, "%u\n", count); |
| 151 | }; |
| 152 | |
| 153 | static DEVICE_ATTR_RO(timestamp0_count); |
| 154 | |
| 155 | static struct attribute *rv3028_attrs[] = { |
| 156 | &dev_attr_timestamp0.attr, |
| 157 | &dev_attr_timestamp0_count.attr, |
| 158 | NULL |
| 159 | }; |
| 160 | |
| 161 | static const struct attribute_group rv3028_attr_group = { |
| 162 | .attrs = rv3028_attrs, |
| 163 | }; |
| 164 | |
| 165 | static irqreturn_t rv3028_handle_irq(int irq, void *dev_id) |
| 166 | { |
| 167 | struct rv3028_data *rv3028 = dev_id; |
| 168 | unsigned long events = 0; |
| 169 | u32 status = 0, ctrl = 0; |
| 170 | |
| 171 | if (regmap_read(rv3028->regmap, RV3028_STATUS, &status) < 0 || |
| 172 | status == 0) { |
| 173 | return IRQ_NONE; |
| 174 | } |
| 175 | |
| 176 | if (status & RV3028_STATUS_PORF) |
| 177 | dev_warn(&rv3028->rtc->dev, "Voltage low, data loss detected.\n"); |
| 178 | |
| 179 | if (status & RV3028_STATUS_TF) { |
| 180 | status |= RV3028_STATUS_TF; |
| 181 | ctrl |= RV3028_CTRL2_TIE; |
| 182 | events |= RTC_PF; |
| 183 | } |
| 184 | |
| 185 | if (status & RV3028_STATUS_AF) { |
| 186 | status |= RV3028_STATUS_AF; |
| 187 | ctrl |= RV3028_CTRL2_AIE; |
| 188 | events |= RTC_AF; |
| 189 | } |
| 190 | |
| 191 | if (status & RV3028_STATUS_UF) { |
| 192 | status |= RV3028_STATUS_UF; |
| 193 | ctrl |= RV3028_CTRL2_UIE; |
| 194 | events |= RTC_UF; |
| 195 | } |
| 196 | |
| 197 | if (events) { |
| 198 | rtc_update_irq(rv3028->rtc, 1, events); |
| 199 | regmap_update_bits(rv3028->regmap, RV3028_STATUS, status, 0); |
| 200 | regmap_update_bits(rv3028->regmap, RV3028_CTRL2, ctrl, 0); |
| 201 | } |
| 202 | |
| 203 | if (status & RV3028_STATUS_EVF) { |
| 204 | sysfs_notify(&rv3028->rtc->dev.kobj, NULL, |
| 205 | dev_attr_timestamp0.attr.name); |
| 206 | dev_warn(&rv3028->rtc->dev, "event detected"); |
| 207 | } |
| 208 | |
| 209 | return IRQ_HANDLED; |
| 210 | } |
| 211 | |
| 212 | static int rv3028_get_time(struct device *dev, struct rtc_time *tm) |
| 213 | { |
| 214 | struct rv3028_data *rv3028 = dev_get_drvdata(dev); |
| 215 | u8 date[7]; |
| 216 | int ret, status; |
| 217 | |
| 218 | ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status); |
| 219 | if (ret < 0) |
| 220 | return ret; |
| 221 | |
| 222 | if (status & RV3028_STATUS_PORF) { |
| 223 | dev_warn(dev, "Voltage low, data is invalid.\n"); |
| 224 | return -EINVAL; |
| 225 | } |
| 226 | |
| 227 | ret = regmap_bulk_read(rv3028->regmap, RV3028_SEC, date, sizeof(date)); |
| 228 | if (ret) |
| 229 | return ret; |
| 230 | |
| 231 | tm->tm_sec = bcd2bin(date[RV3028_SEC] & 0x7f); |
| 232 | tm->tm_min = bcd2bin(date[RV3028_MIN] & 0x7f); |
| 233 | tm->tm_hour = bcd2bin(date[RV3028_HOUR] & 0x3f); |
| 234 | tm->tm_wday = ilog2(date[RV3028_WDAY] & 0x7f); |
| 235 | tm->tm_mday = bcd2bin(date[RV3028_DAY] & 0x3f); |
| 236 | tm->tm_mon = bcd2bin(date[RV3028_MONTH] & 0x1f) - 1; |
| 237 | tm->tm_year = bcd2bin(date[RV3028_YEAR]) + 100; |
| 238 | |
| 239 | return 0; |
| 240 | } |
| 241 | |
| 242 | static int rv3028_set_time(struct device *dev, struct rtc_time *tm) |
| 243 | { |
| 244 | struct rv3028_data *rv3028 = dev_get_drvdata(dev); |
| 245 | u8 date[7]; |
| 246 | int ret; |
| 247 | |
| 248 | date[RV3028_SEC] = bin2bcd(tm->tm_sec); |
| 249 | date[RV3028_MIN] = bin2bcd(tm->tm_min); |
| 250 | date[RV3028_HOUR] = bin2bcd(tm->tm_hour); |
| 251 | date[RV3028_WDAY] = 1 << (tm->tm_wday); |
| 252 | date[RV3028_DAY] = bin2bcd(tm->tm_mday); |
| 253 | date[RV3028_MONTH] = bin2bcd(tm->tm_mon + 1); |
| 254 | date[RV3028_YEAR] = bin2bcd(tm->tm_year - 100); |
| 255 | |
| 256 | /* |
| 257 | * Writing to the Seconds register has the same effect as setting RESET |
| 258 | * bit to 1 |
| 259 | */ |
| 260 | ret = regmap_bulk_write(rv3028->regmap, RV3028_SEC, date, |
| 261 | sizeof(date)); |
| 262 | if (ret) |
| 263 | return ret; |
| 264 | |
| 265 | ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS, |
| 266 | RV3028_STATUS_PORF, 0); |
| 267 | |
| 268 | return ret; |
| 269 | } |
| 270 | |
| 271 | static int rv3028_get_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
| 272 | { |
| 273 | struct rv3028_data *rv3028 = dev_get_drvdata(dev); |
| 274 | u8 alarmvals[3]; |
| 275 | int status, ctrl, ret; |
| 276 | |
| 277 | ret = regmap_bulk_read(rv3028->regmap, RV3028_ALARM_MIN, alarmvals, |
| 278 | sizeof(alarmvals)); |
| 279 | if (ret) |
| 280 | return ret; |
| 281 | |
| 282 | ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status); |
| 283 | if (ret < 0) |
| 284 | return ret; |
| 285 | |
| 286 | ret = regmap_read(rv3028->regmap, RV3028_CTRL2, &ctrl); |
| 287 | if (ret < 0) |
| 288 | return ret; |
| 289 | |
| 290 | alrm->time.tm_sec = 0; |
| 291 | alrm->time.tm_min = bcd2bin(alarmvals[0] & 0x7f); |
| 292 | alrm->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f); |
| 293 | alrm->time.tm_mday = bcd2bin(alarmvals[2] & 0x3f); |
| 294 | |
| 295 | alrm->enabled = !!(ctrl & RV3028_CTRL2_AIE); |
| 296 | alrm->pending = (status & RV3028_STATUS_AF) && alrm->enabled; |
| 297 | |
| 298 | return 0; |
| 299 | } |
| 300 | |
| 301 | static int rv3028_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
| 302 | { |
| 303 | struct rv3028_data *rv3028 = dev_get_drvdata(dev); |
| 304 | u8 alarmvals[3]; |
| 305 | u8 ctrl = 0; |
| 306 | int ret; |
| 307 | |
| 308 | /* The alarm has no seconds, round up to nearest minute */ |
| 309 | if (alrm->time.tm_sec) { |
| 310 | time64_t alarm_time = rtc_tm_to_time64(&alrm->time); |
| 311 | |
| 312 | alarm_time += 60 - alrm->time.tm_sec; |
| 313 | rtc_time64_to_tm(alarm_time, &alrm->time); |
| 314 | } |
| 315 | |
| 316 | ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2, |
| 317 | RV3028_CTRL2_AIE | RV3028_CTRL2_UIE, 0); |
| 318 | if (ret) |
| 319 | return ret; |
| 320 | |
| 321 | alarmvals[0] = bin2bcd(alrm->time.tm_min); |
| 322 | alarmvals[1] = bin2bcd(alrm->time.tm_hour); |
| 323 | alarmvals[2] = bin2bcd(alrm->time.tm_mday); |
| 324 | |
| 325 | ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS, |
| 326 | RV3028_STATUS_AF, 0); |
| 327 | if (ret) |
| 328 | return ret; |
| 329 | |
| 330 | ret = regmap_bulk_write(rv3028->regmap, RV3028_ALARM_MIN, alarmvals, |
| 331 | sizeof(alarmvals)); |
| 332 | if (ret) |
| 333 | return ret; |
| 334 | |
| 335 | if (alrm->enabled) { |
| 336 | if (rv3028->rtc->uie_rtctimer.enabled) |
| 337 | ctrl |= RV3028_CTRL2_UIE; |
| 338 | if (rv3028->rtc->aie_timer.enabled) |
| 339 | ctrl |= RV3028_CTRL2_AIE; |
| 340 | } |
| 341 | |
| 342 | ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2, |
| 343 | RV3028_CTRL2_UIE | RV3028_CTRL2_AIE, ctrl); |
| 344 | |
| 345 | return ret; |
| 346 | } |
| 347 | |
| 348 | static int rv3028_alarm_irq_enable(struct device *dev, unsigned int enabled) |
| 349 | { |
| 350 | struct rv3028_data *rv3028 = dev_get_drvdata(dev); |
| 351 | int ctrl = 0, ret; |
| 352 | |
| 353 | if (enabled) { |
| 354 | if (rv3028->rtc->uie_rtctimer.enabled) |
| 355 | ctrl |= RV3028_CTRL2_UIE; |
| 356 | if (rv3028->rtc->aie_timer.enabled) |
| 357 | ctrl |= RV3028_CTRL2_AIE; |
| 358 | } |
| 359 | |
| 360 | ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS, |
| 361 | RV3028_STATUS_AF | RV3028_STATUS_UF, 0); |
| 362 | if (ret) |
| 363 | return ret; |
| 364 | |
| 365 | ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2, |
| 366 | RV3028_CTRL2_UIE | RV3028_CTRL2_AIE, ctrl); |
| 367 | if (ret) |
| 368 | return ret; |
| 369 | |
| 370 | return 0; |
| 371 | } |
| 372 | |
| 373 | static int rv3028_read_offset(struct device *dev, long *offset) |
| 374 | { |
| 375 | struct rv3028_data *rv3028 = dev_get_drvdata(dev); |
| 376 | int ret, value, steps; |
| 377 | |
| 378 | ret = regmap_read(rv3028->regmap, RV3028_OFFSET, &value); |
| 379 | if (ret < 0) |
| 380 | return ret; |
| 381 | |
| 382 | steps = sign_extend32(value << 1, 8); |
| 383 | |
| 384 | ret = regmap_read(rv3028->regmap, RV3028_BACKUP, &value); |
| 385 | if (ret < 0) |
| 386 | return ret; |
| 387 | |
| 388 | steps += value >> 7; |
| 389 | |
| 390 | *offset = DIV_ROUND_CLOSEST(steps * OFFSET_STEP_PPT, 1000); |
| 391 | |
| 392 | return 0; |
| 393 | } |
| 394 | |
| 395 | static int rv3028_set_offset(struct device *dev, long offset) |
| 396 | { |
| 397 | struct rv3028_data *rv3028 = dev_get_drvdata(dev); |
| 398 | int ret; |
| 399 | |
| 400 | offset = clamp(offset, -244141L, 243187L) * 1000; |
| 401 | offset = DIV_ROUND_CLOSEST(offset, OFFSET_STEP_PPT); |
| 402 | |
| 403 | ret = regmap_write(rv3028->regmap, RV3028_OFFSET, offset >> 1); |
| 404 | if (ret < 0) |
| 405 | return ret; |
| 406 | |
| 407 | return regmap_update_bits(rv3028->regmap, RV3028_BACKUP, BIT(7), |
| 408 | offset << 7); |
| 409 | } |
| 410 | |
| 411 | static int rv3028_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) |
| 412 | { |
| 413 | struct rv3028_data *rv3028 = dev_get_drvdata(dev); |
| 414 | int status, ret = 0; |
| 415 | |
| 416 | switch (cmd) { |
| 417 | case RTC_VL_READ: |
| 418 | ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status); |
| 419 | if (ret < 0) |
| 420 | return ret; |
| 421 | |
| 422 | if (status & RV3028_STATUS_PORF) |
| 423 | dev_warn(&rv3028->rtc->dev, "Voltage low, data loss detected.\n"); |
| 424 | |
| 425 | status &= RV3028_STATUS_PORF; |
| 426 | |
| 427 | if (copy_to_user((void __user *)arg, &status, sizeof(int))) |
| 428 | return -EFAULT; |
| 429 | |
| 430 | return 0; |
| 431 | |
| 432 | case RTC_VL_CLR: |
| 433 | ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS, |
| 434 | RV3028_STATUS_PORF, 0); |
| 435 | |
| 436 | return ret; |
| 437 | |
| 438 | default: |
| 439 | return -ENOIOCTLCMD; |
| 440 | } |
| 441 | } |
| 442 | |
| 443 | static int rv3028_nvram_write(void *priv, unsigned int offset, void *val, |
| 444 | size_t bytes) |
| 445 | { |
| 446 | return regmap_bulk_write(priv, RV3028_RAM1 + offset, val, bytes); |
| 447 | } |
| 448 | |
| 449 | static int rv3028_nvram_read(void *priv, unsigned int offset, void *val, |
| 450 | size_t bytes) |
| 451 | { |
| 452 | return regmap_bulk_read(priv, RV3028_RAM1 + offset, val, bytes); |
| 453 | } |
| 454 | |
| 455 | static int rv3028_eeprom_write(void *priv, unsigned int offset, void *val, |
| 456 | size_t bytes) |
| 457 | { |
| 458 | u32 status, ctrl1; |
| 459 | int i, ret, err; |
| 460 | u8 *buf = val; |
| 461 | |
| 462 | ret = regmap_read(priv, RV3028_CTRL1, &ctrl1); |
| 463 | if (ret) |
| 464 | return ret; |
| 465 | |
| 466 | if (!(ctrl1 & RV3028_CTRL1_EERD)) { |
| 467 | ret = regmap_update_bits(priv, RV3028_CTRL1, |
| 468 | RV3028_CTRL1_EERD, RV3028_CTRL1_EERD); |
| 469 | if (ret) |
| 470 | return ret; |
| 471 | |
| 472 | ret = regmap_read_poll_timeout(priv, RV3028_STATUS, status, |
| 473 | !(status & RV3028_STATUS_EEBUSY), |
| 474 | RV3028_EEBUSY_POLL, |
| 475 | RV3028_EEBUSY_TIMEOUT); |
| 476 | if (ret) |
| 477 | goto restore_eerd; |
| 478 | } |
| 479 | |
| 480 | for (i = 0; i < bytes; i++) { |
| 481 | ret = regmap_write(priv, RV3028_EEPROM_ADDR, offset + i); |
| 482 | if (ret) |
| 483 | goto restore_eerd; |
| 484 | |
| 485 | ret = regmap_write(priv, RV3028_EEPROM_DATA, buf[i]); |
| 486 | if (ret) |
| 487 | goto restore_eerd; |
| 488 | |
| 489 | ret = regmap_write(priv, RV3028_EEPROM_CMD, 0x0); |
| 490 | if (ret) |
| 491 | goto restore_eerd; |
| 492 | |
| 493 | ret = regmap_write(priv, RV3028_EEPROM_CMD, |
| 494 | RV3028_EEPROM_CMD_WRITE); |
| 495 | if (ret) |
| 496 | goto restore_eerd; |
| 497 | |
| 498 | usleep_range(RV3028_EEBUSY_POLL, RV3028_EEBUSY_TIMEOUT); |
| 499 | |
| 500 | ret = regmap_read_poll_timeout(priv, RV3028_STATUS, status, |
| 501 | !(status & RV3028_STATUS_EEBUSY), |
| 502 | RV3028_EEBUSY_POLL, |
| 503 | RV3028_EEBUSY_TIMEOUT); |
| 504 | if (ret) |
| 505 | goto restore_eerd; |
| 506 | } |
| 507 | |
| 508 | restore_eerd: |
| 509 | if (!(ctrl1 & RV3028_CTRL1_EERD)) |
| 510 | { |
| 511 | err = regmap_update_bits(priv, RV3028_CTRL1, RV3028_CTRL1_EERD, |
| 512 | 0); |
| 513 | if (err && !ret) |
| 514 | ret = err; |
| 515 | } |
| 516 | |
| 517 | return ret; |
| 518 | } |
| 519 | |
| 520 | static int rv3028_eeprom_read(void *priv, unsigned int offset, void *val, |
| 521 | size_t bytes) |
| 522 | { |
| 523 | u32 status, ctrl1, data; |
| 524 | int i, ret, err; |
| 525 | u8 *buf = val; |
| 526 | |
| 527 | ret = regmap_read(priv, RV3028_CTRL1, &ctrl1); |
| 528 | if (ret) |
| 529 | return ret; |
| 530 | |
| 531 | if (!(ctrl1 & RV3028_CTRL1_EERD)) { |
| 532 | ret = regmap_update_bits(priv, RV3028_CTRL1, |
| 533 | RV3028_CTRL1_EERD, RV3028_CTRL1_EERD); |
| 534 | if (ret) |
| 535 | return ret; |
| 536 | |
| 537 | ret = regmap_read_poll_timeout(priv, RV3028_STATUS, status, |
| 538 | !(status & RV3028_STATUS_EEBUSY), |
| 539 | RV3028_EEBUSY_POLL, |
| 540 | RV3028_EEBUSY_TIMEOUT); |
| 541 | if (ret) |
| 542 | goto restore_eerd; |
| 543 | } |
| 544 | |
| 545 | for (i = 0; i < bytes; i++) { |
| 546 | ret = regmap_write(priv, RV3028_EEPROM_ADDR, offset + i); |
| 547 | if (ret) |
| 548 | goto restore_eerd; |
| 549 | |
| 550 | ret = regmap_write(priv, RV3028_EEPROM_CMD, 0x0); |
| 551 | if (ret) |
| 552 | goto restore_eerd; |
| 553 | |
| 554 | ret = regmap_write(priv, RV3028_EEPROM_CMD, |
| 555 | RV3028_EEPROM_CMD_READ); |
| 556 | if (ret) |
| 557 | goto restore_eerd; |
| 558 | |
| 559 | ret = regmap_read_poll_timeout(priv, RV3028_STATUS, status, |
| 560 | !(status & RV3028_STATUS_EEBUSY), |
| 561 | RV3028_EEBUSY_POLL, |
| 562 | RV3028_EEBUSY_TIMEOUT); |
| 563 | if (ret) |
| 564 | goto restore_eerd; |
| 565 | |
| 566 | ret = regmap_read(priv, RV3028_EEPROM_DATA, &data); |
| 567 | if (ret) |
| 568 | goto restore_eerd; |
| 569 | buf[i] = data; |
| 570 | } |
| 571 | |
| 572 | restore_eerd: |
| 573 | if (!(ctrl1 & RV3028_CTRL1_EERD)) |
| 574 | { |
| 575 | err = regmap_update_bits(priv, RV3028_CTRL1, RV3028_CTRL1_EERD, |
| 576 | 0); |
| 577 | if (err && !ret) |
| 578 | ret = err; |
| 579 | } |
| 580 | |
| 581 | return ret; |
| 582 | } |
| 583 | |
| 584 | static struct rtc_class_ops rv3028_rtc_ops = { |
| 585 | .read_time = rv3028_get_time, |
| 586 | .set_time = rv3028_set_time, |
| 587 | .read_offset = rv3028_read_offset, |
| 588 | .set_offset = rv3028_set_offset, |
| 589 | .ioctl = rv3028_ioctl, |
| 590 | }; |
| 591 | |
| 592 | static const struct regmap_config regmap_config = { |
| 593 | .reg_bits = 8, |
| 594 | .val_bits = 8, |
| 595 | .max_register = 0x37, |
| 596 | }; |
| 597 | |
| 598 | static int rv3028_probe(struct i2c_client *client) |
| 599 | { |
| 600 | struct rv3028_data *rv3028; |
| 601 | int ret, status; |
| 602 | u32 ohms; |
| 603 | struct nvmem_config nvmem_cfg = { |
| 604 | .name = "rv3028_nvram", |
| 605 | .word_size = 1, |
| 606 | .stride = 1, |
| 607 | .size = 2, |
| 608 | .type = NVMEM_TYPE_BATTERY_BACKED, |
| 609 | .reg_read = rv3028_nvram_read, |
| 610 | .reg_write = rv3028_nvram_write, |
| 611 | }; |
| 612 | struct nvmem_config eeprom_cfg = { |
| 613 | .name = "rv3028_eeprom", |
| 614 | .word_size = 1, |
| 615 | .stride = 1, |
| 616 | .size = 43, |
| 617 | .type = NVMEM_TYPE_EEPROM, |
| 618 | .reg_read = rv3028_eeprom_read, |
| 619 | .reg_write = rv3028_eeprom_write, |
| 620 | }; |
| 621 | |
| 622 | rv3028 = devm_kzalloc(&client->dev, sizeof(struct rv3028_data), |
| 623 | GFP_KERNEL); |
| 624 | if (!rv3028) |
| 625 | return -ENOMEM; |
| 626 | |
| 627 | rv3028->regmap = devm_regmap_init_i2c(client, ®map_config); |
| 628 | |
| 629 | i2c_set_clientdata(client, rv3028); |
| 630 | |
| 631 | ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status); |
| 632 | if (ret < 0) |
| 633 | return ret; |
| 634 | |
| 635 | if (status & RV3028_STATUS_PORF) |
| 636 | dev_warn(&client->dev, "Voltage low, data loss detected.\n"); |
| 637 | |
| 638 | if (status & RV3028_STATUS_AF) |
| 639 | dev_warn(&client->dev, "An alarm may have been missed.\n"); |
| 640 | |
| 641 | rv3028->rtc = devm_rtc_allocate_device(&client->dev); |
| 642 | if (IS_ERR(rv3028->rtc)) { |
| 643 | return PTR_ERR(rv3028->rtc); |
| 644 | } |
| 645 | |
| 646 | if (client->irq > 0) { |
| 647 | ret = devm_request_threaded_irq(&client->dev, client->irq, |
| 648 | NULL, rv3028_handle_irq, |
| 649 | IRQF_TRIGGER_LOW | IRQF_ONESHOT, |
| 650 | "rv3028", rv3028); |
| 651 | if (ret) { |
| 652 | dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n"); |
| 653 | client->irq = 0; |
| 654 | } else { |
| 655 | rv3028_rtc_ops.read_alarm = rv3028_get_alarm; |
| 656 | rv3028_rtc_ops.set_alarm = rv3028_set_alarm; |
| 657 | rv3028_rtc_ops.alarm_irq_enable = rv3028_alarm_irq_enable; |
| 658 | } |
| 659 | } |
| 660 | |
| 661 | ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL1, |
| 662 | RV3028_CTRL1_WADA, RV3028_CTRL1_WADA); |
| 663 | if (ret) |
| 664 | return ret; |
| 665 | |
| 666 | /* setup timestamping */ |
| 667 | ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2, |
| 668 | RV3028_CTRL2_EIE | RV3028_CTRL2_TSE, |
| 669 | RV3028_CTRL2_EIE | RV3028_CTRL2_TSE); |
| 670 | if (ret) |
| 671 | return ret; |
| 672 | |
| 673 | /* setup trickle charger */ |
| 674 | if (!device_property_read_u32(&client->dev, "trickle-resistor-ohms", |
| 675 | &ohms)) { |
| 676 | int i; |
| 677 | |
| 678 | for (i = 0; i < ARRAY_SIZE(rv3028_trickle_resistors); i++) |
| 679 | if (ohms == rv3028_trickle_resistors[i]) |
| 680 | break; |
| 681 | |
| 682 | if (i < ARRAY_SIZE(rv3028_trickle_resistors)) { |
| 683 | ret = regmap_update_bits(rv3028->regmap, RV3028_BACKUP, |
| 684 | RV3028_BACKUP_TCE | |
| 685 | RV3028_BACKUP_TCR_MASK, |
| 686 | RV3028_BACKUP_TCE | i); |
| 687 | if (ret) |
| 688 | return ret; |
| 689 | } else { |
| 690 | dev_warn(&client->dev, "invalid trickle resistor value\n"); |
| 691 | } |
| 692 | } |
| 693 | |
| 694 | ret = rtc_add_group(rv3028->rtc, &rv3028_attr_group); |
| 695 | if (ret) |
| 696 | return ret; |
| 697 | |
| 698 | rv3028->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; |
| 699 | rv3028->rtc->range_max = RTC_TIMESTAMP_END_2099; |
| 700 | rv3028->rtc->ops = &rv3028_rtc_ops; |
| 701 | ret = rtc_register_device(rv3028->rtc); |
| 702 | if (ret) |
| 703 | return ret; |
| 704 | |
| 705 | nvmem_cfg.priv = rv3028->regmap; |
| 706 | rtc_nvmem_register(rv3028->rtc, &nvmem_cfg); |
| 707 | eeprom_cfg.priv = rv3028->regmap; |
| 708 | rtc_nvmem_register(rv3028->rtc, &eeprom_cfg); |
| 709 | |
| 710 | rv3028->rtc->max_user_freq = 1; |
| 711 | |
| 712 | return 0; |
| 713 | } |
| 714 | |
| 715 | static const struct of_device_id rv3028_of_match[] = { |
| 716 | { .compatible = "microcrystal,rv3028", }, |
| 717 | { } |
| 718 | }; |
| 719 | MODULE_DEVICE_TABLE(of, rv3028_of_match); |
| 720 | |
| 721 | static struct i2c_driver rv3028_driver = { |
| 722 | .driver = { |
| 723 | .name = "rtc-rv3028", |
| 724 | .of_match_table = of_match_ptr(rv3028_of_match), |
| 725 | }, |
| 726 | .probe_new = rv3028_probe, |
| 727 | }; |
| 728 | module_i2c_driver(rv3028_driver); |
| 729 | |
| 730 | MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>"); |
| 731 | MODULE_DESCRIPTION("Micro Crystal RV3028 RTC driver"); |
| 732 | MODULE_LICENSE("GPL v2"); |