1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * rtc-ds1307.c - RTC driver for some mostly-compatible I2C chips. 4 * 5 * Copyright (C) 2005 James Chapman (ds1337 core) 6 * Copyright (C) 2006 David Brownell 7 * Copyright (C) 2009 Matthias Fuchs (rx8025 support) 8 * Copyright (C) 2012 Bertrand Achard (nvram access fixes) 9 */ 10 11 #include <linux/bcd.h> 12 #include <linux/i2c.h> 13 #include <linux/init.h> 14 #include <linux/kstrtox.h> 15 #include <linux/mod_devicetable.h> 16 #include <linux/module.h> 17 #include <linux/property.h> 18 #include <linux/rtc/ds1307.h> 19 #include <linux/rtc.h> 20 #include <linux/slab.h> 21 #include <linux/string.h> 22 #include <linux/hwmon.h> 23 #include <linux/hwmon-sysfs.h> 24 #include <linux/clk-provider.h> 25 #include <linux/regmap.h> 26 #include <linux/watchdog.h> 27 28 /* 29 * We can't determine type by probing, but if we expect pre-Linux code 30 * to have set the chip up as a clock (turning on the oscillator and 31 * setting the date and time), Linux can ignore the non-clock features. 32 * That's a natural job for a factory or repair bench. 33 */ 34 enum ds_type { 35 unknown_ds_type, /* always first and 0 */ 36 ds_1307, 37 ds_1308, 38 ds_1337, 39 ds_1338, 40 ds_1339, 41 ds_1340, 42 ds_1341, 43 ds_1388, 44 ds_3231, 45 m41t0, 46 m41t00, 47 m41t11, 48 mcp794xx, 49 rx_8025, 50 rx_8130, 51 last_ds_type /* always last */ 52 /* rs5c372 too? different address... */ 53 }; 54 55 /* RTC registers don't differ much, except for the century flag */ 56 #define DS1307_REG_SECS 0x00 /* 00-59 */ 57 # define DS1307_BIT_CH 0x80 58 # define DS1340_BIT_nEOSC 0x80 59 # define MCP794XX_BIT_ST 0x80 60 #define DS1307_REG_MIN 0x01 /* 00-59 */ 61 # define M41T0_BIT_OF 0x80 62 #define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */ 63 # define DS1307_BIT_12HR 0x40 /* in REG_HOUR */ 64 # define DS1307_BIT_PM 0x20 /* in REG_HOUR */ 65 # define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */ 66 # define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */ 67 #define DS1307_REG_WDAY 0x03 /* 01-07 */ 68 # define MCP794XX_BIT_VBATEN 0x08 69 #define DS1307_REG_MDAY 0x04 /* 01-31 */ 70 #define DS1307_REG_MONTH 0x05 /* 01-12 */ 71 # define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */ 72 #define DS1307_REG_YEAR 0x06 /* 00-99 */ 73 74 /* 75 * Other registers (control, status, alarms, trickle charge, NVRAM, etc) 76 * start at 7, and they differ a LOT. Only control and status matter for 77 * basic RTC date and time functionality; be careful using them. 78 */ 79 #define DS1307_REG_CONTROL 0x07 /* or ds1338 */ 80 # define DS1307_BIT_OUT 0x80 81 # define DS1338_BIT_OSF 0x20 82 # define DS1307_BIT_SQWE 0x10 83 # define DS1307_BIT_RS1 0x02 84 # define DS1307_BIT_RS0 0x01 85 #define DS1337_REG_CONTROL 0x0e 86 # define DS1337_BIT_nEOSC 0x80 87 # define DS1339_BIT_BBSQI 0x20 88 # define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */ 89 # define DS1337_BIT_RS2 0x10 90 # define DS1337_BIT_RS1 0x08 91 # define DS1337_BIT_INTCN 0x04 92 # define DS1337_BIT_A2IE 0x02 93 # define DS1337_BIT_A1IE 0x01 94 #define DS1340_REG_CONTROL 0x07 95 # define DS1340_BIT_OUT 0x80 96 # define DS1340_BIT_FT 0x40 97 # define DS1340_BIT_CALIB_SIGN 0x20 98 # define DS1340_M_CALIBRATION 0x1f 99 #define DS1340_REG_FLAG 0x09 100 # define DS1340_BIT_OSF 0x80 101 #define DS1337_REG_STATUS 0x0f 102 # define DS1337_BIT_OSF 0x80 103 # define DS3231_BIT_EN32KHZ 0x08 104 # define DS1337_BIT_A2I 0x02 105 # define DS1337_BIT_A1I 0x01 106 #define DS1339_REG_ALARM1_SECS 0x07 107 108 #define DS13XX_TRICKLE_CHARGER_MAGIC 0xa0 109 110 #define RX8025_REG_CTRL1 0x0e 111 # define RX8025_BIT_2412 0x20 112 #define RX8025_REG_CTRL2 0x0f 113 # define RX8025_BIT_PON 0x10 114 # define RX8025_BIT_VDET 0x40 115 # define RX8025_BIT_XST 0x20 116 117 #define RX8130_REG_ALARM_MIN 0x17 118 #define RX8130_REG_ALARM_HOUR 0x18 119 #define RX8130_REG_ALARM_WEEK_OR_DAY 0x19 120 #define RX8130_REG_EXTENSION 0x1c 121 #define RX8130_REG_EXTENSION_WADA BIT(3) 122 #define RX8130_REG_FLAG 0x1d 123 #define RX8130_REG_FLAG_VLF BIT(1) 124 #define RX8130_REG_FLAG_AF BIT(3) 125 #define RX8130_REG_CONTROL0 0x1e 126 #define RX8130_REG_CONTROL0_AIE BIT(3) 127 #define RX8130_REG_CONTROL1 0x1f 128 #define RX8130_REG_CONTROL1_INIEN BIT(4) 129 #define RX8130_REG_CONTROL1_CHGEN BIT(5) 130 131 #define MCP794XX_REG_CONTROL 0x07 132 # define MCP794XX_BIT_ALM0_EN 0x10 133 # define MCP794XX_BIT_ALM1_EN 0x20 134 #define MCP794XX_REG_ALARM0_BASE 0x0a 135 #define MCP794XX_REG_ALARM0_CTRL 0x0d 136 #define MCP794XX_REG_ALARM1_BASE 0x11 137 #define MCP794XX_REG_ALARM1_CTRL 0x14 138 # define MCP794XX_BIT_ALMX_IF BIT(3) 139 # define MCP794XX_BIT_ALMX_C0 BIT(4) 140 # define MCP794XX_BIT_ALMX_C1 BIT(5) 141 # define MCP794XX_BIT_ALMX_C2 BIT(6) 142 # define MCP794XX_BIT_ALMX_POL BIT(7) 143 # define MCP794XX_MSK_ALMX_MATCH (MCP794XX_BIT_ALMX_C0 | \ 144 MCP794XX_BIT_ALMX_C1 | \ 145 MCP794XX_BIT_ALMX_C2) 146 147 #define M41TXX_REG_CONTROL 0x07 148 # define M41TXX_BIT_OUT BIT(7) 149 # define M41TXX_BIT_FT BIT(6) 150 # define M41TXX_BIT_CALIB_SIGN BIT(5) 151 # define M41TXX_M_CALIBRATION GENMASK(4, 0) 152 153 #define DS1388_REG_WDOG_HUN_SECS 0x08 154 #define DS1388_REG_WDOG_SECS 0x09 155 #define DS1388_REG_FLAG 0x0b 156 # define DS1388_BIT_WF BIT(6) 157 # define DS1388_BIT_OSF BIT(7) 158 #define DS1388_REG_CONTROL 0x0c 159 # define DS1388_BIT_RST BIT(0) 160 # define DS1388_BIT_WDE BIT(1) 161 # define DS1388_BIT_nEOSC BIT(7) 162 163 /* negative offset step is -2.034ppm */ 164 #define M41TXX_NEG_OFFSET_STEP_PPB 2034 165 /* positive offset step is +4.068ppm */ 166 #define M41TXX_POS_OFFSET_STEP_PPB 4068 167 /* Min and max values supported with 'offset' interface by M41TXX */ 168 #define M41TXX_MIN_OFFSET ((-31) * M41TXX_NEG_OFFSET_STEP_PPB) 169 #define M41TXX_MAX_OFFSET ((31) * M41TXX_POS_OFFSET_STEP_PPB) 170 171 struct ds1307 { 172 enum ds_type type; 173 struct device *dev; 174 struct regmap *regmap; 175 const char *name; 176 struct rtc_device *rtc; 177 #ifdef CONFIG_COMMON_CLK 178 struct clk_hw clks[2]; 179 #endif 180 }; 181 182 struct chip_desc { 183 unsigned alarm:1; 184 u16 nvram_offset; 185 u16 nvram_size; 186 u8 offset; /* register's offset */ 187 u8 century_reg; 188 u8 century_enable_bit; 189 u8 century_bit; 190 u8 bbsqi_bit; 191 irq_handler_t irq_handler; 192 const struct rtc_class_ops *rtc_ops; 193 u16 trickle_charger_reg; 194 u8 (*do_trickle_setup)(struct ds1307 *, u32, 195 bool); 196 /* Does the RTC require trickle-resistor-ohms to select the value of 197 * the resistor between Vcc and Vbackup? 198 */ 199 bool requires_trickle_resistor; 200 /* Some RTC's batteries and supercaps were charged by default, others 201 * allow charging but were not configured previously to do so. 202 * Remember this behavior to stay backwards compatible. 203 */ 204 bool charge_default; 205 }; 206 207 static const struct chip_desc chips[last_ds_type]; 208 209 static int ds1307_get_time(struct device *dev, struct rtc_time *t) 210 { 211 struct ds1307 *ds1307 = dev_get_drvdata(dev); 212 int tmp, ret; 213 const struct chip_desc *chip = &chips[ds1307->type]; 214 u8 regs[7]; 215 216 if (ds1307->type == rx_8130) { 217 unsigned int regflag; 218 ret = regmap_read(ds1307->regmap, RX8130_REG_FLAG, ®flag); 219 if (ret) { 220 dev_err(dev, "%s error %d\n", "read", ret); 221 return ret; 222 } 223 224 if (regflag & RX8130_REG_FLAG_VLF) { 225 dev_warn_once(dev, "oscillator failed, set time!\n"); 226 return -EINVAL; 227 } 228 } 229 230 /* read the RTC date and time registers all at once */ 231 ret = regmap_bulk_read(ds1307->regmap, chip->offset, regs, 232 sizeof(regs)); 233 if (ret) { 234 dev_err(dev, "%s error %d\n", "read", ret); 235 return ret; 236 } 237 238 dev_dbg(dev, "%s: %7ph\n", "read", regs); 239 240 /* if oscillator fail bit is set, no data can be trusted */ 241 if (ds1307->type == m41t0 && 242 regs[DS1307_REG_MIN] & M41T0_BIT_OF) { 243 dev_warn_once(dev, "oscillator failed, set time!\n"); 244 return -EINVAL; 245 } 246 247 tmp = regs[DS1307_REG_SECS]; 248 switch (ds1307->type) { 249 case ds_1307: 250 case m41t0: 251 case m41t00: 252 case m41t11: 253 if (tmp & DS1307_BIT_CH) 254 return -EINVAL; 255 break; 256 case ds_1308: 257 case ds_1338: 258 if (tmp & DS1307_BIT_CH) 259 return -EINVAL; 260 261 ret = regmap_read(ds1307->regmap, DS1307_REG_CONTROL, &tmp); 262 if (ret) 263 return ret; 264 if (tmp & DS1338_BIT_OSF) 265 return -EINVAL; 266 break; 267 case ds_1340: 268 if (tmp & DS1340_BIT_nEOSC) 269 return -EINVAL; 270 271 ret = regmap_read(ds1307->regmap, DS1340_REG_FLAG, &tmp); 272 if (ret) 273 return ret; 274 if (tmp & DS1340_BIT_OSF) 275 return -EINVAL; 276 break; 277 case ds_1388: 278 ret = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &tmp); 279 if (ret) 280 return ret; 281 if (tmp & DS1388_BIT_OSF) 282 return -EINVAL; 283 break; 284 case mcp794xx: 285 if (!(tmp & MCP794XX_BIT_ST)) 286 return -EINVAL; 287 288 break; 289 default: 290 break; 291 } 292 293 t->tm_sec = bcd2bin(regs[DS1307_REG_SECS] & 0x7f); 294 t->tm_min = bcd2bin(regs[DS1307_REG_MIN] & 0x7f); 295 tmp = regs[DS1307_REG_HOUR] & 0x3f; 296 t->tm_hour = bcd2bin(tmp); 297 /* rx8130 is bit position, not BCD */ 298 if (ds1307->type == rx_8130) 299 t->tm_wday = fls(regs[DS1307_REG_WDAY] & 0x7f); 300 else 301 t->tm_wday = bcd2bin(regs[DS1307_REG_WDAY] & 0x07) - 1; 302 t->tm_mday = bcd2bin(regs[DS1307_REG_MDAY] & 0x3f); 303 tmp = regs[DS1307_REG_MONTH] & 0x1f; 304 t->tm_mon = bcd2bin(tmp) - 1; 305 t->tm_year = bcd2bin(regs[DS1307_REG_YEAR]) + 100; 306 307 if (regs[chip->century_reg] & chip->century_bit && 308 IS_ENABLED(CONFIG_RTC_DRV_DS1307_CENTURY)) 309 t->tm_year += 100; 310 311 dev_dbg(dev, "%s secs=%d, mins=%d, " 312 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n", 313 "read", t->tm_sec, t->tm_min, 314 t->tm_hour, t->tm_mday, 315 t->tm_mon, t->tm_year, t->tm_wday); 316 317 return 0; 318 } 319 320 static int ds1307_set_time(struct device *dev, struct rtc_time *t) 321 { 322 struct ds1307 *ds1307 = dev_get_drvdata(dev); 323 const struct chip_desc *chip = &chips[ds1307->type]; 324 int result; 325 int tmp; 326 u8 regs[7]; 327 328 dev_dbg(dev, "%s secs=%d, mins=%d, " 329 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n", 330 "write", t->tm_sec, t->tm_min, 331 t->tm_hour, t->tm_mday, 332 t->tm_mon, t->tm_year, t->tm_wday); 333 334 if (t->tm_year < 100) 335 return -EINVAL; 336 337 #ifdef CONFIG_RTC_DRV_DS1307_CENTURY 338 if (t->tm_year > (chip->century_bit ? 299 : 199)) 339 return -EINVAL; 340 #else 341 if (t->tm_year > 199) 342 return -EINVAL; 343 #endif 344 345 regs[DS1307_REG_SECS] = bin2bcd(t->tm_sec); 346 regs[DS1307_REG_MIN] = bin2bcd(t->tm_min); 347 regs[DS1307_REG_HOUR] = bin2bcd(t->tm_hour); 348 /* rx8130 is bit position, not BCD */ 349 if (ds1307->type == rx_8130) 350 regs[DS1307_REG_WDAY] = 1 << t->tm_wday; 351 else 352 regs[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1); 353 regs[DS1307_REG_MDAY] = bin2bcd(t->tm_mday); 354 regs[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1); 355 356 /* assume 20YY not 19YY */ 357 tmp = t->tm_year - 100; 358 regs[DS1307_REG_YEAR] = bin2bcd(tmp); 359 360 if (chip->century_enable_bit) 361 regs[chip->century_reg] |= chip->century_enable_bit; 362 if (t->tm_year > 199 && chip->century_bit) 363 regs[chip->century_reg] |= chip->century_bit; 364 365 switch (ds1307->type) { 366 case ds_1308: 367 case ds_1338: 368 regmap_update_bits(ds1307->regmap, DS1307_REG_CONTROL, 369 DS1338_BIT_OSF, 0); 370 break; 371 case ds_1340: 372 regmap_update_bits(ds1307->regmap, DS1340_REG_FLAG, 373 DS1340_BIT_OSF, 0); 374 break; 375 case ds_1388: 376 regmap_update_bits(ds1307->regmap, DS1388_REG_FLAG, 377 DS1388_BIT_OSF, 0); 378 break; 379 case mcp794xx: 380 /* 381 * these bits were cleared when preparing the date/time 382 * values and need to be set again before writing the 383 * regsfer out to the device. 384 */ 385 regs[DS1307_REG_SECS] |= MCP794XX_BIT_ST; 386 regs[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN; 387 break; 388 default: 389 break; 390 } 391 392 dev_dbg(dev, "%s: %7ph\n", "write", regs); 393 394 result = regmap_bulk_write(ds1307->regmap, chip->offset, regs, 395 sizeof(regs)); 396 if (result) { 397 dev_err(dev, "%s error %d\n", "write", result); 398 return result; 399 } 400 401 if (ds1307->type == rx_8130) { 402 /* clear Voltage Loss Flag as data is available now */ 403 result = regmap_write(ds1307->regmap, RX8130_REG_FLAG, 404 ~(u8)RX8130_REG_FLAG_VLF); 405 if (result) { 406 dev_err(dev, "%s error %d\n", "write", result); 407 return result; 408 } 409 } 410 411 return 0; 412 } 413 414 static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t) 415 { 416 struct ds1307 *ds1307 = dev_get_drvdata(dev); 417 int ret; 418 u8 regs[9]; 419 420 /* read all ALARM1, ALARM2, and status registers at once */ 421 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, 422 regs, sizeof(regs)); 423 if (ret) { 424 dev_err(dev, "%s error %d\n", "alarm read", ret); 425 return ret; 426 } 427 428 dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read", 429 ®s[0], ®s[4], ®s[7]); 430 431 /* 432 * report alarm time (ALARM1); assume 24 hour and day-of-month modes, 433 * and that all four fields are checked matches 434 */ 435 t->time.tm_sec = bcd2bin(regs[0] & 0x7f); 436 t->time.tm_min = bcd2bin(regs[1] & 0x7f); 437 t->time.tm_hour = bcd2bin(regs[2] & 0x3f); 438 t->time.tm_mday = bcd2bin(regs[3] & 0x3f); 439 440 /* ... and status */ 441 t->enabled = !!(regs[7] & DS1337_BIT_A1IE); 442 t->pending = !!(regs[8] & DS1337_BIT_A1I); 443 444 dev_dbg(dev, "%s secs=%d, mins=%d, " 445 "hours=%d, mday=%d, enabled=%d, pending=%d\n", 446 "alarm read", t->time.tm_sec, t->time.tm_min, 447 t->time.tm_hour, t->time.tm_mday, 448 t->enabled, t->pending); 449 450 return 0; 451 } 452 453 static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t) 454 { 455 struct ds1307 *ds1307 = dev_get_drvdata(dev); 456 unsigned char regs[9]; 457 u8 control, status; 458 int ret; 459 460 dev_dbg(dev, "%s secs=%d, mins=%d, " 461 "hours=%d, mday=%d, enabled=%d, pending=%d\n", 462 "alarm set", t->time.tm_sec, t->time.tm_min, 463 t->time.tm_hour, t->time.tm_mday, 464 t->enabled, t->pending); 465 466 /* read current status of both alarms and the chip */ 467 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs, 468 sizeof(regs)); 469 if (ret) { 470 dev_err(dev, "%s error %d\n", "alarm write", ret); 471 return ret; 472 } 473 control = regs[7]; 474 status = regs[8]; 475 476 dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)", 477 ®s[0], ®s[4], control, status); 478 479 /* set ALARM1, using 24 hour and day-of-month modes */ 480 regs[0] = bin2bcd(t->time.tm_sec); 481 regs[1] = bin2bcd(t->time.tm_min); 482 regs[2] = bin2bcd(t->time.tm_hour); 483 regs[3] = bin2bcd(t->time.tm_mday); 484 485 /* set ALARM2 to non-garbage */ 486 regs[4] = 0; 487 regs[5] = 0; 488 regs[6] = 0; 489 490 /* disable alarms */ 491 regs[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE); 492 regs[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I); 493 494 ret = regmap_bulk_write(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs, 495 sizeof(regs)); 496 if (ret) { 497 dev_err(dev, "can't set alarm time\n"); 498 return ret; 499 } 500 501 /* optionally enable ALARM1 */ 502 if (t->enabled) { 503 dev_dbg(dev, "alarm IRQ armed\n"); 504 regs[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */ 505 regmap_write(ds1307->regmap, DS1337_REG_CONTROL, regs[7]); 506 } 507 508 return 0; 509 } 510 511 static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled) 512 { 513 struct ds1307 *ds1307 = dev_get_drvdata(dev); 514 515 return regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL, 516 DS1337_BIT_A1IE, 517 enabled ? DS1337_BIT_A1IE : 0); 518 } 519 520 static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307, u32 ohms, bool diode) 521 { 522 u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE : 523 DS1307_TRICKLE_CHARGER_NO_DIODE; 524 525 setup |= DS13XX_TRICKLE_CHARGER_MAGIC; 526 527 switch (ohms) { 528 case 250: 529 setup |= DS1307_TRICKLE_CHARGER_250_OHM; 530 break; 531 case 2000: 532 setup |= DS1307_TRICKLE_CHARGER_2K_OHM; 533 break; 534 case 4000: 535 setup |= DS1307_TRICKLE_CHARGER_4K_OHM; 536 break; 537 default: 538 dev_warn(ds1307->dev, 539 "Unsupported ohm value %u in dt\n", ohms); 540 return 0; 541 } 542 return setup; 543 } 544 545 static u8 do_trickle_setup_rx8130(struct ds1307 *ds1307, u32 ohms, bool diode) 546 { 547 /* make sure that the backup battery is enabled */ 548 u8 setup = RX8130_REG_CONTROL1_INIEN; 549 if (diode) 550 setup |= RX8130_REG_CONTROL1_CHGEN; 551 552 return setup; 553 } 554 555 static irqreturn_t rx8130_irq(int irq, void *dev_id) 556 { 557 struct ds1307 *ds1307 = dev_id; 558 u8 ctl[3]; 559 int ret; 560 561 rtc_lock(ds1307->rtc); 562 563 /* Read control registers. */ 564 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 565 sizeof(ctl)); 566 if (ret < 0) 567 goto out; 568 if (!(ctl[1] & RX8130_REG_FLAG_AF)) 569 goto out; 570 ctl[1] &= ~RX8130_REG_FLAG_AF; 571 ctl[2] &= ~RX8130_REG_CONTROL0_AIE; 572 573 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 574 sizeof(ctl)); 575 if (ret < 0) 576 goto out; 577 578 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); 579 580 out: 581 rtc_unlock(ds1307->rtc); 582 583 return IRQ_HANDLED; 584 } 585 586 static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t) 587 { 588 struct ds1307 *ds1307 = dev_get_drvdata(dev); 589 u8 ald[3], ctl[3]; 590 int ret; 591 592 /* Read alarm registers. */ 593 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_ALARM_MIN, ald, 594 sizeof(ald)); 595 if (ret < 0) 596 return ret; 597 598 /* Read control registers. */ 599 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 600 sizeof(ctl)); 601 if (ret < 0) 602 return ret; 603 604 t->enabled = !!(ctl[2] & RX8130_REG_CONTROL0_AIE); 605 t->pending = !!(ctl[1] & RX8130_REG_FLAG_AF); 606 607 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */ 608 t->time.tm_sec = -1; 609 t->time.tm_min = bcd2bin(ald[0] & 0x7f); 610 t->time.tm_hour = bcd2bin(ald[1] & 0x7f); 611 t->time.tm_wday = -1; 612 t->time.tm_mday = bcd2bin(ald[2] & 0x7f); 613 t->time.tm_mon = -1; 614 t->time.tm_year = -1; 615 t->time.tm_yday = -1; 616 t->time.tm_isdst = -1; 617 618 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d enabled=%d\n", 619 __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour, 620 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled); 621 622 return 0; 623 } 624 625 static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t) 626 { 627 struct ds1307 *ds1307 = dev_get_drvdata(dev); 628 u8 ald[3], ctl[3]; 629 int ret; 630 631 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d " 632 "enabled=%d pending=%d\n", __func__, 633 t->time.tm_sec, t->time.tm_min, t->time.tm_hour, 634 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, 635 t->enabled, t->pending); 636 637 /* Read control registers. */ 638 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 639 sizeof(ctl)); 640 if (ret < 0) 641 return ret; 642 643 ctl[0] &= RX8130_REG_EXTENSION_WADA; 644 ctl[1] &= ~RX8130_REG_FLAG_AF; 645 ctl[2] &= ~RX8130_REG_CONTROL0_AIE; 646 647 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 648 sizeof(ctl)); 649 if (ret < 0) 650 return ret; 651 652 /* Hardware alarm precision is 1 minute! */ 653 ald[0] = bin2bcd(t->time.tm_min); 654 ald[1] = bin2bcd(t->time.tm_hour); 655 ald[2] = bin2bcd(t->time.tm_mday); 656 657 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_ALARM_MIN, ald, 658 sizeof(ald)); 659 if (ret < 0) 660 return ret; 661 662 if (!t->enabled) 663 return 0; 664 665 ctl[2] |= RX8130_REG_CONTROL0_AIE; 666 667 return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, ctl[2]); 668 } 669 670 static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled) 671 { 672 struct ds1307 *ds1307 = dev_get_drvdata(dev); 673 int ret, reg; 674 675 ret = regmap_read(ds1307->regmap, RX8130_REG_CONTROL0, ®); 676 if (ret < 0) 677 return ret; 678 679 if (enabled) 680 reg |= RX8130_REG_CONTROL0_AIE; 681 else 682 reg &= ~RX8130_REG_CONTROL0_AIE; 683 684 return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, reg); 685 } 686 687 static irqreturn_t mcp794xx_irq(int irq, void *dev_id) 688 { 689 struct ds1307 *ds1307 = dev_id; 690 struct mutex *lock = &ds1307->rtc->ops_lock; 691 int reg, ret; 692 693 mutex_lock(lock); 694 695 /* Check and clear alarm 0 interrupt flag. */ 696 ret = regmap_read(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, ®); 697 if (ret) 698 goto out; 699 if (!(reg & MCP794XX_BIT_ALMX_IF)) 700 goto out; 701 reg &= ~MCP794XX_BIT_ALMX_IF; 702 ret = regmap_write(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, reg); 703 if (ret) 704 goto out; 705 706 /* Disable alarm 0. */ 707 ret = regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL, 708 MCP794XX_BIT_ALM0_EN, 0); 709 if (ret) 710 goto out; 711 712 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); 713 714 out: 715 mutex_unlock(lock); 716 717 return IRQ_HANDLED; 718 } 719 720 static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t) 721 { 722 struct ds1307 *ds1307 = dev_get_drvdata(dev); 723 u8 regs[10]; 724 int ret; 725 726 /* Read control and alarm 0 registers. */ 727 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs, 728 sizeof(regs)); 729 if (ret) 730 return ret; 731 732 t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN); 733 734 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */ 735 t->time.tm_sec = bcd2bin(regs[3] & 0x7f); 736 t->time.tm_min = bcd2bin(regs[4] & 0x7f); 737 t->time.tm_hour = bcd2bin(regs[5] & 0x3f); 738 t->time.tm_wday = bcd2bin(regs[6] & 0x7) - 1; 739 t->time.tm_mday = bcd2bin(regs[7] & 0x3f); 740 t->time.tm_mon = bcd2bin(regs[8] & 0x1f) - 1; 741 t->time.tm_year = -1; 742 t->time.tm_yday = -1; 743 t->time.tm_isdst = -1; 744 745 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d " 746 "enabled=%d polarity=%d irq=%d match=%lu\n", __func__, 747 t->time.tm_sec, t->time.tm_min, t->time.tm_hour, 748 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled, 749 !!(regs[6] & MCP794XX_BIT_ALMX_POL), 750 !!(regs[6] & MCP794XX_BIT_ALMX_IF), 751 (regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4); 752 753 return 0; 754 } 755 756 /* 757 * We may have a random RTC weekday, therefore calculate alarm weekday based 758 * on current weekday we read from the RTC timekeeping regs 759 */ 760 static int mcp794xx_alm_weekday(struct device *dev, struct rtc_time *tm_alarm) 761 { 762 struct rtc_time tm_now; 763 int days_now, days_alarm, ret; 764 765 ret = ds1307_get_time(dev, &tm_now); 766 if (ret) 767 return ret; 768 769 days_now = div_s64(rtc_tm_to_time64(&tm_now), 24 * 60 * 60); 770 days_alarm = div_s64(rtc_tm_to_time64(tm_alarm), 24 * 60 * 60); 771 772 return (tm_now.tm_wday + days_alarm - days_now) % 7 + 1; 773 } 774 775 static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t) 776 { 777 struct ds1307 *ds1307 = dev_get_drvdata(dev); 778 unsigned char regs[10]; 779 int wday, ret; 780 781 wday = mcp794xx_alm_weekday(dev, &t->time); 782 if (wday < 0) 783 return wday; 784 785 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d " 786 "enabled=%d pending=%d\n", __func__, 787 t->time.tm_sec, t->time.tm_min, t->time.tm_hour, 788 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, 789 t->enabled, t->pending); 790 791 /* Read control and alarm 0 registers. */ 792 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs, 793 sizeof(regs)); 794 if (ret) 795 return ret; 796 797 /* Set alarm 0, using 24-hour and day-of-month modes. */ 798 regs[3] = bin2bcd(t->time.tm_sec); 799 regs[4] = bin2bcd(t->time.tm_min); 800 regs[5] = bin2bcd(t->time.tm_hour); 801 regs[6] = wday; 802 regs[7] = bin2bcd(t->time.tm_mday); 803 regs[8] = bin2bcd(t->time.tm_mon + 1); 804 805 /* Clear the alarm 0 interrupt flag. */ 806 regs[6] &= ~MCP794XX_BIT_ALMX_IF; 807 /* Set alarm match: second, minute, hour, day, date, month. */ 808 regs[6] |= MCP794XX_MSK_ALMX_MATCH; 809 /* Disable interrupt. We will not enable until completely programmed */ 810 regs[0] &= ~MCP794XX_BIT_ALM0_EN; 811 812 ret = regmap_bulk_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs, 813 sizeof(regs)); 814 if (ret) 815 return ret; 816 817 if (!t->enabled) 818 return 0; 819 regs[0] |= MCP794XX_BIT_ALM0_EN; 820 return regmap_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs[0]); 821 } 822 823 static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled) 824 { 825 struct ds1307 *ds1307 = dev_get_drvdata(dev); 826 827 return regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL, 828 MCP794XX_BIT_ALM0_EN, 829 enabled ? MCP794XX_BIT_ALM0_EN : 0); 830 } 831 832 static int m41txx_rtc_read_offset(struct device *dev, long *offset) 833 { 834 struct ds1307 *ds1307 = dev_get_drvdata(dev); 835 unsigned int ctrl_reg; 836 u8 val; 837 838 regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg); 839 840 val = ctrl_reg & M41TXX_M_CALIBRATION; 841 842 /* check if positive */ 843 if (ctrl_reg & M41TXX_BIT_CALIB_SIGN) 844 *offset = (val * M41TXX_POS_OFFSET_STEP_PPB); 845 else 846 *offset = -(val * M41TXX_NEG_OFFSET_STEP_PPB); 847 848 return 0; 849 } 850 851 static int m41txx_rtc_set_offset(struct device *dev, long offset) 852 { 853 struct ds1307 *ds1307 = dev_get_drvdata(dev); 854 unsigned int ctrl_reg; 855 856 if ((offset < M41TXX_MIN_OFFSET) || (offset > M41TXX_MAX_OFFSET)) 857 return -ERANGE; 858 859 if (offset >= 0) { 860 ctrl_reg = DIV_ROUND_CLOSEST(offset, 861 M41TXX_POS_OFFSET_STEP_PPB); 862 ctrl_reg |= M41TXX_BIT_CALIB_SIGN; 863 } else { 864 ctrl_reg = DIV_ROUND_CLOSEST(abs(offset), 865 M41TXX_NEG_OFFSET_STEP_PPB); 866 } 867 868 return regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, 869 M41TXX_M_CALIBRATION | M41TXX_BIT_CALIB_SIGN, 870 ctrl_reg); 871 } 872 873 #ifdef CONFIG_WATCHDOG_CORE 874 static int ds1388_wdt_start(struct watchdog_device *wdt_dev) 875 { 876 struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); 877 u8 regs[2]; 878 int ret; 879 880 ret = regmap_update_bits(ds1307->regmap, DS1388_REG_FLAG, 881 DS1388_BIT_WF, 0); 882 if (ret) 883 return ret; 884 885 ret = regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL, 886 DS1388_BIT_WDE | DS1388_BIT_RST, 0); 887 if (ret) 888 return ret; 889 890 /* 891 * watchdog timeouts are measured in seconds. So ignore hundredths of 892 * seconds field. 893 */ 894 regs[0] = 0; 895 regs[1] = bin2bcd(wdt_dev->timeout); 896 897 ret = regmap_bulk_write(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs, 898 sizeof(regs)); 899 if (ret) 900 return ret; 901 902 return regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL, 903 DS1388_BIT_WDE | DS1388_BIT_RST, 904 DS1388_BIT_WDE | DS1388_BIT_RST); 905 } 906 907 static int ds1388_wdt_stop(struct watchdog_device *wdt_dev) 908 { 909 struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); 910 911 return regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL, 912 DS1388_BIT_WDE | DS1388_BIT_RST, 0); 913 } 914 915 static int ds1388_wdt_ping(struct watchdog_device *wdt_dev) 916 { 917 struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); 918 u8 regs[2]; 919 920 return regmap_bulk_read(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs, 921 sizeof(regs)); 922 } 923 924 static int ds1388_wdt_set_timeout(struct watchdog_device *wdt_dev, 925 unsigned int val) 926 { 927 struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); 928 u8 regs[2]; 929 930 wdt_dev->timeout = val; 931 regs[0] = 0; 932 regs[1] = bin2bcd(wdt_dev->timeout); 933 934 return regmap_bulk_write(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs, 935 sizeof(regs)); 936 } 937 #endif 938 939 static const struct rtc_class_ops rx8130_rtc_ops = { 940 .read_time = ds1307_get_time, 941 .set_time = ds1307_set_time, 942 .read_alarm = rx8130_read_alarm, 943 .set_alarm = rx8130_set_alarm, 944 .alarm_irq_enable = rx8130_alarm_irq_enable, 945 }; 946 947 static const struct rtc_class_ops mcp794xx_rtc_ops = { 948 .read_time = ds1307_get_time, 949 .set_time = ds1307_set_time, 950 .read_alarm = mcp794xx_read_alarm, 951 .set_alarm = mcp794xx_set_alarm, 952 .alarm_irq_enable = mcp794xx_alarm_irq_enable, 953 }; 954 955 static const struct rtc_class_ops m41txx_rtc_ops = { 956 .read_time = ds1307_get_time, 957 .set_time = ds1307_set_time, 958 .read_alarm = ds1337_read_alarm, 959 .set_alarm = ds1337_set_alarm, 960 .alarm_irq_enable = ds1307_alarm_irq_enable, 961 .read_offset = m41txx_rtc_read_offset, 962 .set_offset = m41txx_rtc_set_offset, 963 }; 964 965 static const struct chip_desc chips[last_ds_type] = { 966 [ds_1307] = { 967 .nvram_offset = 8, 968 .nvram_size = 56, 969 }, 970 [ds_1308] = { 971 .nvram_offset = 8, 972 .nvram_size = 56, 973 }, 974 [ds_1337] = { 975 .alarm = 1, 976 .century_reg = DS1307_REG_MONTH, 977 .century_bit = DS1337_BIT_CENTURY, 978 }, 979 [ds_1338] = { 980 .nvram_offset = 8, 981 .nvram_size = 56, 982 }, 983 [ds_1339] = { 984 .alarm = 1, 985 .century_reg = DS1307_REG_MONTH, 986 .century_bit = DS1337_BIT_CENTURY, 987 .bbsqi_bit = DS1339_BIT_BBSQI, 988 .trickle_charger_reg = 0x10, 989 .do_trickle_setup = &do_trickle_setup_ds1339, 990 .requires_trickle_resistor = true, 991 .charge_default = true, 992 }, 993 [ds_1340] = { 994 .century_reg = DS1307_REG_HOUR, 995 .century_enable_bit = DS1340_BIT_CENTURY_EN, 996 .century_bit = DS1340_BIT_CENTURY, 997 .do_trickle_setup = &do_trickle_setup_ds1339, 998 .trickle_charger_reg = 0x08, 999 .requires_trickle_resistor = true, 1000 .charge_default = true, 1001 }, 1002 [ds_1341] = { 1003 .century_reg = DS1307_REG_MONTH, 1004 .century_bit = DS1337_BIT_CENTURY, 1005 }, 1006 [ds_1388] = { 1007 .offset = 1, 1008 .trickle_charger_reg = 0x0a, 1009 }, 1010 [ds_3231] = { 1011 .alarm = 1, 1012 .century_reg = DS1307_REG_MONTH, 1013 .century_bit = DS1337_BIT_CENTURY, 1014 .bbsqi_bit = DS3231_BIT_BBSQW, 1015 }, 1016 [rx_8130] = { 1017 .alarm = 1, 1018 /* this is battery backed SRAM */ 1019 .nvram_offset = 0x20, 1020 .nvram_size = 4, /* 32bit (4 word x 8 bit) */ 1021 .offset = 0x10, 1022 .irq_handler = rx8130_irq, 1023 .rtc_ops = &rx8130_rtc_ops, 1024 .trickle_charger_reg = RX8130_REG_CONTROL1, 1025 .do_trickle_setup = &do_trickle_setup_rx8130, 1026 }, 1027 [m41t0] = { 1028 .rtc_ops = &m41txx_rtc_ops, 1029 }, 1030 [m41t00] = { 1031 .rtc_ops = &m41txx_rtc_ops, 1032 }, 1033 [m41t11] = { 1034 /* this is battery backed SRAM */ 1035 .nvram_offset = 8, 1036 .nvram_size = 56, 1037 .rtc_ops = &m41txx_rtc_ops, 1038 }, 1039 [mcp794xx] = { 1040 .alarm = 1, 1041 /* this is battery backed SRAM */ 1042 .nvram_offset = 0x20, 1043 .nvram_size = 0x40, 1044 .irq_handler = mcp794xx_irq, 1045 .rtc_ops = &mcp794xx_rtc_ops, 1046 }, 1047 }; 1048 1049 static const struct i2c_device_id ds1307_id[] = { 1050 { "ds1307", ds_1307 }, 1051 { "ds1308", ds_1308 }, 1052 { "ds1337", ds_1337 }, 1053 { "ds1338", ds_1338 }, 1054 { "ds1339", ds_1339 }, 1055 { "ds1388", ds_1388 }, 1056 { "ds1340", ds_1340 }, 1057 { "ds1341", ds_1341 }, 1058 { "ds3231", ds_3231 }, 1059 { "m41t0", m41t0 }, 1060 { "m41t00", m41t00 }, 1061 { "m41t11", m41t11 }, 1062 { "mcp7940x", mcp794xx }, 1063 { "mcp7941x", mcp794xx }, 1064 { "pt7c4338", ds_1307 }, 1065 { "rx8025", rx_8025 }, 1066 { "isl12057", ds_1337 }, 1067 { "rx8130", rx_8130 }, 1068 { } 1069 }; 1070 MODULE_DEVICE_TABLE(i2c, ds1307_id); 1071 1072 static const struct of_device_id ds1307_of_match[] = { 1073 { 1074 .compatible = "dallas,ds1307", 1075 .data = (void *)ds_1307 1076 }, 1077 { 1078 .compatible = "dallas,ds1308", 1079 .data = (void *)ds_1308 1080 }, 1081 { 1082 .compatible = "dallas,ds1337", 1083 .data = (void *)ds_1337 1084 }, 1085 { 1086 .compatible = "dallas,ds1338", 1087 .data = (void *)ds_1338 1088 }, 1089 { 1090 .compatible = "dallas,ds1339", 1091 .data = (void *)ds_1339 1092 }, 1093 { 1094 .compatible = "dallas,ds1388", 1095 .data = (void *)ds_1388 1096 }, 1097 { 1098 .compatible = "dallas,ds1340", 1099 .data = (void *)ds_1340 1100 }, 1101 { 1102 .compatible = "dallas,ds1341", 1103 .data = (void *)ds_1341 1104 }, 1105 { 1106 .compatible = "maxim,ds3231", 1107 .data = (void *)ds_3231 1108 }, 1109 { 1110 .compatible = "st,m41t0", 1111 .data = (void *)m41t0 1112 }, 1113 { 1114 .compatible = "st,m41t00", 1115 .data = (void *)m41t00 1116 }, 1117 { 1118 .compatible = "st,m41t11", 1119 .data = (void *)m41t11 1120 }, 1121 { 1122 .compatible = "microchip,mcp7940x", 1123 .data = (void *)mcp794xx 1124 }, 1125 { 1126 .compatible = "microchip,mcp7941x", 1127 .data = (void *)mcp794xx 1128 }, 1129 { 1130 .compatible = "pericom,pt7c4338", 1131 .data = (void *)ds_1307 1132 }, 1133 { 1134 .compatible = "epson,rx8025", 1135 .data = (void *)rx_8025 1136 }, 1137 { 1138 .compatible = "isil,isl12057", 1139 .data = (void *)ds_1337 1140 }, 1141 { 1142 .compatible = "epson,rx8130", 1143 .data = (void *)rx_8130 1144 }, 1145 { } 1146 }; 1147 MODULE_DEVICE_TABLE(of, ds1307_of_match); 1148 1149 /* 1150 * The ds1337 and ds1339 both have two alarms, but we only use the first 1151 * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm 1152 * signal; ds1339 chips have only one alarm signal. 1153 */ 1154 static irqreturn_t ds1307_irq(int irq, void *dev_id) 1155 { 1156 struct ds1307 *ds1307 = dev_id; 1157 struct mutex *lock = &ds1307->rtc->ops_lock; 1158 int stat, ret; 1159 1160 mutex_lock(lock); 1161 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &stat); 1162 if (ret) 1163 goto out; 1164 1165 if (stat & DS1337_BIT_A1I) { 1166 stat &= ~DS1337_BIT_A1I; 1167 regmap_write(ds1307->regmap, DS1337_REG_STATUS, stat); 1168 1169 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL, 1170 DS1337_BIT_A1IE, 0); 1171 if (ret) 1172 goto out; 1173 1174 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); 1175 } 1176 1177 out: 1178 mutex_unlock(lock); 1179 1180 return IRQ_HANDLED; 1181 } 1182 1183 /*----------------------------------------------------------------------*/ 1184 1185 static const struct rtc_class_ops ds13xx_rtc_ops = { 1186 .read_time = ds1307_get_time, 1187 .set_time = ds1307_set_time, 1188 .read_alarm = ds1337_read_alarm, 1189 .set_alarm = ds1337_set_alarm, 1190 .alarm_irq_enable = ds1307_alarm_irq_enable, 1191 }; 1192 1193 static ssize_t frequency_test_store(struct device *dev, 1194 struct device_attribute *attr, 1195 const char *buf, size_t count) 1196 { 1197 struct ds1307 *ds1307 = dev_get_drvdata(dev->parent); 1198 bool freq_test_en; 1199 int ret; 1200 1201 ret = kstrtobool(buf, &freq_test_en); 1202 if (ret) { 1203 dev_err(dev, "Failed to store RTC Frequency Test attribute\n"); 1204 return ret; 1205 } 1206 1207 regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, M41TXX_BIT_FT, 1208 freq_test_en ? M41TXX_BIT_FT : 0); 1209 1210 return count; 1211 } 1212 1213 static ssize_t frequency_test_show(struct device *dev, 1214 struct device_attribute *attr, 1215 char *buf) 1216 { 1217 struct ds1307 *ds1307 = dev_get_drvdata(dev->parent); 1218 unsigned int ctrl_reg; 1219 1220 regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg); 1221 1222 return sysfs_emit(buf, (ctrl_reg & M41TXX_BIT_FT) ? "on\n" : "off\n"); 1223 } 1224 1225 static DEVICE_ATTR_RW(frequency_test); 1226 1227 static struct attribute *rtc_freq_test_attrs[] = { 1228 &dev_attr_frequency_test.attr, 1229 NULL, 1230 }; 1231 1232 static const struct attribute_group rtc_freq_test_attr_group = { 1233 .attrs = rtc_freq_test_attrs, 1234 }; 1235 1236 static int ds1307_add_frequency_test(struct ds1307 *ds1307) 1237 { 1238 int err; 1239 1240 switch (ds1307->type) { 1241 case m41t0: 1242 case m41t00: 1243 case m41t11: 1244 err = rtc_add_group(ds1307->rtc, &rtc_freq_test_attr_group); 1245 if (err) 1246 return err; 1247 break; 1248 default: 1249 break; 1250 } 1251 1252 return 0; 1253 } 1254 1255 /*----------------------------------------------------------------------*/ 1256 1257 static int ds1307_nvram_read(void *priv, unsigned int offset, void *val, 1258 size_t bytes) 1259 { 1260 struct ds1307 *ds1307 = priv; 1261 const struct chip_desc *chip = &chips[ds1307->type]; 1262 1263 return regmap_bulk_read(ds1307->regmap, chip->nvram_offset + offset, 1264 val, bytes); 1265 } 1266 1267 static int ds1307_nvram_write(void *priv, unsigned int offset, void *val, 1268 size_t bytes) 1269 { 1270 struct ds1307 *ds1307 = priv; 1271 const struct chip_desc *chip = &chips[ds1307->type]; 1272 1273 return regmap_bulk_write(ds1307->regmap, chip->nvram_offset + offset, 1274 val, bytes); 1275 } 1276 1277 /*----------------------------------------------------------------------*/ 1278 1279 static u8 ds1307_trickle_init(struct ds1307 *ds1307, 1280 const struct chip_desc *chip) 1281 { 1282 u32 ohms, chargeable; 1283 bool diode = chip->charge_default; 1284 1285 if (!chip->do_trickle_setup) 1286 return 0; 1287 1288 if (device_property_read_u32(ds1307->dev, "trickle-resistor-ohms", 1289 &ohms) && chip->requires_trickle_resistor) 1290 return 0; 1291 1292 /* aux-voltage-chargeable takes precedence over the deprecated 1293 * trickle-diode-disable 1294 */ 1295 if (!device_property_read_u32(ds1307->dev, "aux-voltage-chargeable", 1296 &chargeable)) { 1297 switch (chargeable) { 1298 case 0: 1299 diode = false; 1300 break; 1301 case 1: 1302 diode = true; 1303 break; 1304 default: 1305 dev_warn(ds1307->dev, 1306 "unsupported aux-voltage-chargeable value\n"); 1307 break; 1308 } 1309 } else if (device_property_read_bool(ds1307->dev, 1310 "trickle-diode-disable")) { 1311 diode = false; 1312 } 1313 1314 return chip->do_trickle_setup(ds1307, ohms, diode); 1315 } 1316 1317 /*----------------------------------------------------------------------*/ 1318 1319 #if IS_REACHABLE(CONFIG_HWMON) 1320 1321 /* 1322 * Temperature sensor support for ds3231 devices. 1323 */ 1324 1325 #define DS3231_REG_TEMPERATURE 0x11 1326 1327 /* 1328 * A user-initiated temperature conversion is not started by this function, 1329 * so the temperature is updated once every 64 seconds. 1330 */ 1331 static int ds3231_hwmon_read_temp(struct device *dev, s32 *mC) 1332 { 1333 struct ds1307 *ds1307 = dev_get_drvdata(dev); 1334 u8 temp_buf[2]; 1335 s16 temp; 1336 int ret; 1337 1338 ret = regmap_bulk_read(ds1307->regmap, DS3231_REG_TEMPERATURE, 1339 temp_buf, sizeof(temp_buf)); 1340 if (ret) 1341 return ret; 1342 /* 1343 * Temperature is represented as a 10-bit code with a resolution of 1344 * 0.25 degree celsius and encoded in two's complement format. 1345 */ 1346 temp = (temp_buf[0] << 8) | temp_buf[1]; 1347 temp >>= 6; 1348 *mC = temp * 250; 1349 1350 return 0; 1351 } 1352 1353 static ssize_t ds3231_hwmon_show_temp(struct device *dev, 1354 struct device_attribute *attr, char *buf) 1355 { 1356 int ret; 1357 s32 temp; 1358 1359 ret = ds3231_hwmon_read_temp(dev, &temp); 1360 if (ret) 1361 return ret; 1362 1363 return sprintf(buf, "%d\n", temp); 1364 } 1365 static SENSOR_DEVICE_ATTR(temp1_input, 0444, ds3231_hwmon_show_temp, 1366 NULL, 0); 1367 1368 static struct attribute *ds3231_hwmon_attrs[] = { 1369 &sensor_dev_attr_temp1_input.dev_attr.attr, 1370 NULL, 1371 }; 1372 ATTRIBUTE_GROUPS(ds3231_hwmon); 1373 1374 static void ds1307_hwmon_register(struct ds1307 *ds1307) 1375 { 1376 struct device *dev; 1377 1378 if (ds1307->type != ds_3231) 1379 return; 1380 1381 dev = devm_hwmon_device_register_with_groups(ds1307->dev, ds1307->name, 1382 ds1307, 1383 ds3231_hwmon_groups); 1384 if (IS_ERR(dev)) { 1385 dev_warn(ds1307->dev, "unable to register hwmon device %ld\n", 1386 PTR_ERR(dev)); 1387 } 1388 } 1389 1390 #else 1391 1392 static void ds1307_hwmon_register(struct ds1307 *ds1307) 1393 { 1394 } 1395 1396 #endif /* CONFIG_RTC_DRV_DS1307_HWMON */ 1397 1398 /*----------------------------------------------------------------------*/ 1399 1400 /* 1401 * Square-wave output support for DS3231 1402 * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3231.pdf 1403 */ 1404 #ifdef CONFIG_COMMON_CLK 1405 1406 enum { 1407 DS3231_CLK_SQW = 0, 1408 DS3231_CLK_32KHZ, 1409 }; 1410 1411 #define clk_sqw_to_ds1307(clk) \ 1412 container_of(clk, struct ds1307, clks[DS3231_CLK_SQW]) 1413 #define clk_32khz_to_ds1307(clk) \ 1414 container_of(clk, struct ds1307, clks[DS3231_CLK_32KHZ]) 1415 1416 static int ds3231_clk_sqw_rates[] = { 1417 1, 1418 1024, 1419 4096, 1420 8192, 1421 }; 1422 1423 static int ds1337_write_control(struct ds1307 *ds1307, u8 mask, u8 value) 1424 { 1425 struct mutex *lock = &ds1307->rtc->ops_lock; 1426 int ret; 1427 1428 mutex_lock(lock); 1429 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL, 1430 mask, value); 1431 mutex_unlock(lock); 1432 1433 return ret; 1434 } 1435 1436 static unsigned long ds3231_clk_sqw_recalc_rate(struct clk_hw *hw, 1437 unsigned long parent_rate) 1438 { 1439 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1440 int control, ret; 1441 int rate_sel = 0; 1442 1443 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control); 1444 if (ret) 1445 return ret; 1446 if (control & DS1337_BIT_RS1) 1447 rate_sel += 1; 1448 if (control & DS1337_BIT_RS2) 1449 rate_sel += 2; 1450 1451 return ds3231_clk_sqw_rates[rate_sel]; 1452 } 1453 1454 static long ds3231_clk_sqw_round_rate(struct clk_hw *hw, unsigned long rate, 1455 unsigned long *prate) 1456 { 1457 int i; 1458 1459 for (i = ARRAY_SIZE(ds3231_clk_sqw_rates) - 1; i >= 0; i--) { 1460 if (ds3231_clk_sqw_rates[i] <= rate) 1461 return ds3231_clk_sqw_rates[i]; 1462 } 1463 1464 return 0; 1465 } 1466 1467 static int ds3231_clk_sqw_set_rate(struct clk_hw *hw, unsigned long rate, 1468 unsigned long parent_rate) 1469 { 1470 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1471 int control = 0; 1472 int rate_sel; 1473 1474 for (rate_sel = 0; rate_sel < ARRAY_SIZE(ds3231_clk_sqw_rates); 1475 rate_sel++) { 1476 if (ds3231_clk_sqw_rates[rate_sel] == rate) 1477 break; 1478 } 1479 1480 if (rate_sel == ARRAY_SIZE(ds3231_clk_sqw_rates)) 1481 return -EINVAL; 1482 1483 if (rate_sel & 1) 1484 control |= DS1337_BIT_RS1; 1485 if (rate_sel & 2) 1486 control |= DS1337_BIT_RS2; 1487 1488 return ds1337_write_control(ds1307, DS1337_BIT_RS1 | DS1337_BIT_RS2, 1489 control); 1490 } 1491 1492 static int ds3231_clk_sqw_prepare(struct clk_hw *hw) 1493 { 1494 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1495 1496 return ds1337_write_control(ds1307, DS1337_BIT_INTCN, 0); 1497 } 1498 1499 static void ds3231_clk_sqw_unprepare(struct clk_hw *hw) 1500 { 1501 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1502 1503 ds1337_write_control(ds1307, DS1337_BIT_INTCN, DS1337_BIT_INTCN); 1504 } 1505 1506 static int ds3231_clk_sqw_is_prepared(struct clk_hw *hw) 1507 { 1508 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1509 int control, ret; 1510 1511 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control); 1512 if (ret) 1513 return ret; 1514 1515 return !(control & DS1337_BIT_INTCN); 1516 } 1517 1518 static const struct clk_ops ds3231_clk_sqw_ops = { 1519 .prepare = ds3231_clk_sqw_prepare, 1520 .unprepare = ds3231_clk_sqw_unprepare, 1521 .is_prepared = ds3231_clk_sqw_is_prepared, 1522 .recalc_rate = ds3231_clk_sqw_recalc_rate, 1523 .round_rate = ds3231_clk_sqw_round_rate, 1524 .set_rate = ds3231_clk_sqw_set_rate, 1525 }; 1526 1527 static unsigned long ds3231_clk_32khz_recalc_rate(struct clk_hw *hw, 1528 unsigned long parent_rate) 1529 { 1530 return 32768; 1531 } 1532 1533 static int ds3231_clk_32khz_control(struct ds1307 *ds1307, bool enable) 1534 { 1535 struct mutex *lock = &ds1307->rtc->ops_lock; 1536 int ret; 1537 1538 mutex_lock(lock); 1539 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_STATUS, 1540 DS3231_BIT_EN32KHZ, 1541 enable ? DS3231_BIT_EN32KHZ : 0); 1542 mutex_unlock(lock); 1543 1544 return ret; 1545 } 1546 1547 static int ds3231_clk_32khz_prepare(struct clk_hw *hw) 1548 { 1549 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw); 1550 1551 return ds3231_clk_32khz_control(ds1307, true); 1552 } 1553 1554 static void ds3231_clk_32khz_unprepare(struct clk_hw *hw) 1555 { 1556 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw); 1557 1558 ds3231_clk_32khz_control(ds1307, false); 1559 } 1560 1561 static int ds3231_clk_32khz_is_prepared(struct clk_hw *hw) 1562 { 1563 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw); 1564 int status, ret; 1565 1566 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &status); 1567 if (ret) 1568 return ret; 1569 1570 return !!(status & DS3231_BIT_EN32KHZ); 1571 } 1572 1573 static const struct clk_ops ds3231_clk_32khz_ops = { 1574 .prepare = ds3231_clk_32khz_prepare, 1575 .unprepare = ds3231_clk_32khz_unprepare, 1576 .is_prepared = ds3231_clk_32khz_is_prepared, 1577 .recalc_rate = ds3231_clk_32khz_recalc_rate, 1578 }; 1579 1580 static const char *ds3231_clks_names[] = { 1581 [DS3231_CLK_SQW] = "ds3231_clk_sqw", 1582 [DS3231_CLK_32KHZ] = "ds3231_clk_32khz", 1583 }; 1584 1585 static struct clk_init_data ds3231_clks_init[] = { 1586 [DS3231_CLK_SQW] = { 1587 .ops = &ds3231_clk_sqw_ops, 1588 }, 1589 [DS3231_CLK_32KHZ] = { 1590 .ops = &ds3231_clk_32khz_ops, 1591 }, 1592 }; 1593 1594 static int ds3231_clks_register(struct ds1307 *ds1307) 1595 { 1596 struct device_node *node = ds1307->dev->of_node; 1597 struct clk_onecell_data *onecell; 1598 int i; 1599 1600 onecell = devm_kzalloc(ds1307->dev, sizeof(*onecell), GFP_KERNEL); 1601 if (!onecell) 1602 return -ENOMEM; 1603 1604 onecell->clk_num = ARRAY_SIZE(ds3231_clks_init); 1605 onecell->clks = devm_kcalloc(ds1307->dev, onecell->clk_num, 1606 sizeof(onecell->clks[0]), GFP_KERNEL); 1607 if (!onecell->clks) 1608 return -ENOMEM; 1609 1610 /* optional override of the clockname */ 1611 device_property_read_string_array(ds1307->dev, "clock-output-names", 1612 ds3231_clks_names, 1613 ARRAY_SIZE(ds3231_clks_names)); 1614 1615 for (i = 0; i < ARRAY_SIZE(ds3231_clks_init); i++) { 1616 struct clk_init_data init = ds3231_clks_init[i]; 1617 1618 /* 1619 * Interrupt signal due to alarm conditions and square-wave 1620 * output share same pin, so don't initialize both. 1621 */ 1622 if (i == DS3231_CLK_SQW && test_bit(RTC_FEATURE_ALARM, ds1307->rtc->features)) 1623 continue; 1624 1625 init.name = ds3231_clks_names[i]; 1626 ds1307->clks[i].init = &init; 1627 1628 onecell->clks[i] = devm_clk_register(ds1307->dev, 1629 &ds1307->clks[i]); 1630 if (IS_ERR(onecell->clks[i])) 1631 return PTR_ERR(onecell->clks[i]); 1632 } 1633 1634 if (node) 1635 of_clk_add_provider(node, of_clk_src_onecell_get, onecell); 1636 1637 return 0; 1638 } 1639 1640 static void ds1307_clks_register(struct ds1307 *ds1307) 1641 { 1642 int ret; 1643 1644 if (ds1307->type != ds_3231) 1645 return; 1646 1647 ret = ds3231_clks_register(ds1307); 1648 if (ret) { 1649 dev_warn(ds1307->dev, "unable to register clock device %d\n", 1650 ret); 1651 } 1652 } 1653 1654 #else 1655 1656 static void ds1307_clks_register(struct ds1307 *ds1307) 1657 { 1658 } 1659 1660 #endif /* CONFIG_COMMON_CLK */ 1661 1662 #ifdef CONFIG_WATCHDOG_CORE 1663 static const struct watchdog_info ds1388_wdt_info = { 1664 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, 1665 .identity = "DS1388 watchdog", 1666 }; 1667 1668 static const struct watchdog_ops ds1388_wdt_ops = { 1669 .owner = THIS_MODULE, 1670 .start = ds1388_wdt_start, 1671 .stop = ds1388_wdt_stop, 1672 .ping = ds1388_wdt_ping, 1673 .set_timeout = ds1388_wdt_set_timeout, 1674 1675 }; 1676 1677 static void ds1307_wdt_register(struct ds1307 *ds1307) 1678 { 1679 struct watchdog_device *wdt; 1680 int err; 1681 int val; 1682 1683 if (ds1307->type != ds_1388) 1684 return; 1685 1686 wdt = devm_kzalloc(ds1307->dev, sizeof(*wdt), GFP_KERNEL); 1687 if (!wdt) 1688 return; 1689 1690 err = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &val); 1691 if (!err && val & DS1388_BIT_WF) 1692 wdt->bootstatus = WDIOF_CARDRESET; 1693 1694 wdt->info = &ds1388_wdt_info; 1695 wdt->ops = &ds1388_wdt_ops; 1696 wdt->timeout = 99; 1697 wdt->max_timeout = 99; 1698 wdt->min_timeout = 1; 1699 1700 watchdog_init_timeout(wdt, 0, ds1307->dev); 1701 watchdog_set_drvdata(wdt, ds1307); 1702 devm_watchdog_register_device(ds1307->dev, wdt); 1703 } 1704 #else 1705 static void ds1307_wdt_register(struct ds1307 *ds1307) 1706 { 1707 } 1708 #endif /* CONFIG_WATCHDOG_CORE */ 1709 1710 static const struct regmap_config regmap_config = { 1711 .reg_bits = 8, 1712 .val_bits = 8, 1713 }; 1714 1715 static int ds1307_probe(struct i2c_client *client) 1716 { 1717 const struct i2c_device_id *id = i2c_client_get_device_id(client); 1718 struct ds1307 *ds1307; 1719 const void *match; 1720 int err = -ENODEV; 1721 int tmp; 1722 const struct chip_desc *chip; 1723 bool want_irq; 1724 bool ds1307_can_wakeup_device = false; 1725 unsigned char regs[8]; 1726 struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev); 1727 u8 trickle_charger_setup = 0; 1728 1729 ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL); 1730 if (!ds1307) 1731 return -ENOMEM; 1732 1733 dev_set_drvdata(&client->dev, ds1307); 1734 ds1307->dev = &client->dev; 1735 ds1307->name = client->name; 1736 1737 ds1307->regmap = devm_regmap_init_i2c(client, ®map_config); 1738 if (IS_ERR(ds1307->regmap)) { 1739 dev_err(ds1307->dev, "regmap allocation failed\n"); 1740 return PTR_ERR(ds1307->regmap); 1741 } 1742 1743 i2c_set_clientdata(client, ds1307); 1744 1745 match = device_get_match_data(&client->dev); 1746 if (match) { 1747 ds1307->type = (enum ds_type)match; 1748 chip = &chips[ds1307->type]; 1749 } else if (id) { 1750 chip = &chips[id->driver_data]; 1751 ds1307->type = id->driver_data; 1752 } else { 1753 return -ENODEV; 1754 } 1755 1756 want_irq = client->irq > 0 && chip->alarm; 1757 1758 if (!pdata) 1759 trickle_charger_setup = ds1307_trickle_init(ds1307, chip); 1760 else if (pdata->trickle_charger_setup) 1761 trickle_charger_setup = pdata->trickle_charger_setup; 1762 1763 if (trickle_charger_setup && chip->trickle_charger_reg) { 1764 dev_dbg(ds1307->dev, 1765 "writing trickle charger info 0x%x to 0x%x\n", 1766 trickle_charger_setup, chip->trickle_charger_reg); 1767 regmap_write(ds1307->regmap, chip->trickle_charger_reg, 1768 trickle_charger_setup); 1769 } 1770 1771 /* 1772 * For devices with no IRQ directly connected to the SoC, the RTC chip 1773 * can be forced as a wakeup source by stating that explicitly in 1774 * the device's .dts file using the "wakeup-source" boolean property. 1775 * If the "wakeup-source" property is set, don't request an IRQ. 1776 * This will guarantee the 'wakealarm' sysfs entry is available on the device, 1777 * if supported by the RTC. 1778 */ 1779 if (chip->alarm && device_property_read_bool(&client->dev, "wakeup-source")) 1780 ds1307_can_wakeup_device = true; 1781 1782 switch (ds1307->type) { 1783 case ds_1337: 1784 case ds_1339: 1785 case ds_1341: 1786 case ds_3231: 1787 /* get registers that the "rtc" read below won't read... */ 1788 err = regmap_bulk_read(ds1307->regmap, DS1337_REG_CONTROL, 1789 regs, 2); 1790 if (err) { 1791 dev_dbg(ds1307->dev, "read error %d\n", err); 1792 goto exit; 1793 } 1794 1795 /* oscillator off? turn it on, so clock can tick. */ 1796 if (regs[0] & DS1337_BIT_nEOSC) 1797 regs[0] &= ~DS1337_BIT_nEOSC; 1798 1799 /* 1800 * Using IRQ or defined as wakeup-source? 1801 * Disable the square wave and both alarms. 1802 * For some variants, be sure alarms can trigger when we're 1803 * running on Vbackup (BBSQI/BBSQW) 1804 */ 1805 if (want_irq || ds1307_can_wakeup_device) { 1806 regs[0] |= DS1337_BIT_INTCN | chip->bbsqi_bit; 1807 regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE); 1808 } 1809 1810 regmap_write(ds1307->regmap, DS1337_REG_CONTROL, 1811 regs[0]); 1812 1813 /* oscillator fault? clear flag, and warn */ 1814 if (regs[1] & DS1337_BIT_OSF) { 1815 regmap_write(ds1307->regmap, DS1337_REG_STATUS, 1816 regs[1] & ~DS1337_BIT_OSF); 1817 dev_warn(ds1307->dev, "SET TIME!\n"); 1818 } 1819 break; 1820 1821 case rx_8025: 1822 err = regmap_bulk_read(ds1307->regmap, 1823 RX8025_REG_CTRL1 << 4 | 0x08, regs, 2); 1824 if (err) { 1825 dev_dbg(ds1307->dev, "read error %d\n", err); 1826 goto exit; 1827 } 1828 1829 /* oscillator off? turn it on, so clock can tick. */ 1830 if (!(regs[1] & RX8025_BIT_XST)) { 1831 regs[1] |= RX8025_BIT_XST; 1832 regmap_write(ds1307->regmap, 1833 RX8025_REG_CTRL2 << 4 | 0x08, 1834 regs[1]); 1835 dev_warn(ds1307->dev, 1836 "oscillator stop detected - SET TIME!\n"); 1837 } 1838 1839 if (regs[1] & RX8025_BIT_PON) { 1840 regs[1] &= ~RX8025_BIT_PON; 1841 regmap_write(ds1307->regmap, 1842 RX8025_REG_CTRL2 << 4 | 0x08, 1843 regs[1]); 1844 dev_warn(ds1307->dev, "power-on detected\n"); 1845 } 1846 1847 if (regs[1] & RX8025_BIT_VDET) { 1848 regs[1] &= ~RX8025_BIT_VDET; 1849 regmap_write(ds1307->regmap, 1850 RX8025_REG_CTRL2 << 4 | 0x08, 1851 regs[1]); 1852 dev_warn(ds1307->dev, "voltage drop detected\n"); 1853 } 1854 1855 /* make sure we are running in 24hour mode */ 1856 if (!(regs[0] & RX8025_BIT_2412)) { 1857 u8 hour; 1858 1859 /* switch to 24 hour mode */ 1860 regmap_write(ds1307->regmap, 1861 RX8025_REG_CTRL1 << 4 | 0x08, 1862 regs[0] | RX8025_BIT_2412); 1863 1864 err = regmap_bulk_read(ds1307->regmap, 1865 RX8025_REG_CTRL1 << 4 | 0x08, 1866 regs, 2); 1867 if (err) { 1868 dev_dbg(ds1307->dev, "read error %d\n", err); 1869 goto exit; 1870 } 1871 1872 /* correct hour */ 1873 hour = bcd2bin(regs[DS1307_REG_HOUR]); 1874 if (hour == 12) 1875 hour = 0; 1876 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM) 1877 hour += 12; 1878 1879 regmap_write(ds1307->regmap, 1880 DS1307_REG_HOUR << 4 | 0x08, hour); 1881 } 1882 break; 1883 case ds_1388: 1884 err = regmap_read(ds1307->regmap, DS1388_REG_CONTROL, &tmp); 1885 if (err) { 1886 dev_dbg(ds1307->dev, "read error %d\n", err); 1887 goto exit; 1888 } 1889 1890 /* oscillator off? turn it on, so clock can tick. */ 1891 if (tmp & DS1388_BIT_nEOSC) { 1892 tmp &= ~DS1388_BIT_nEOSC; 1893 regmap_write(ds1307->regmap, DS1388_REG_CONTROL, tmp); 1894 } 1895 break; 1896 default: 1897 break; 1898 } 1899 1900 /* read RTC registers */ 1901 err = regmap_bulk_read(ds1307->regmap, chip->offset, regs, 1902 sizeof(regs)); 1903 if (err) { 1904 dev_dbg(ds1307->dev, "read error %d\n", err); 1905 goto exit; 1906 } 1907 1908 if (ds1307->type == mcp794xx && 1909 !(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) { 1910 regmap_write(ds1307->regmap, DS1307_REG_WDAY, 1911 regs[DS1307_REG_WDAY] | 1912 MCP794XX_BIT_VBATEN); 1913 } 1914 1915 tmp = regs[DS1307_REG_HOUR]; 1916 switch (ds1307->type) { 1917 case ds_1340: 1918 case m41t0: 1919 case m41t00: 1920 case m41t11: 1921 /* 1922 * NOTE: ignores century bits; fix before deploying 1923 * systems that will run through year 2100. 1924 */ 1925 break; 1926 case rx_8025: 1927 break; 1928 default: 1929 if (!(tmp & DS1307_BIT_12HR)) 1930 break; 1931 1932 /* 1933 * Be sure we're in 24 hour mode. Multi-master systems 1934 * take note... 1935 */ 1936 tmp = bcd2bin(tmp & 0x1f); 1937 if (tmp == 12) 1938 tmp = 0; 1939 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM) 1940 tmp += 12; 1941 regmap_write(ds1307->regmap, chip->offset + DS1307_REG_HOUR, 1942 bin2bcd(tmp)); 1943 } 1944 1945 ds1307->rtc = devm_rtc_allocate_device(ds1307->dev); 1946 if (IS_ERR(ds1307->rtc)) 1947 return PTR_ERR(ds1307->rtc); 1948 1949 if (want_irq || ds1307_can_wakeup_device) 1950 device_set_wakeup_capable(ds1307->dev, true); 1951 else 1952 clear_bit(RTC_FEATURE_ALARM, ds1307->rtc->features); 1953 1954 if (ds1307_can_wakeup_device && !want_irq) { 1955 dev_info(ds1307->dev, 1956 "'wakeup-source' is set, request for an IRQ is disabled!\n"); 1957 /* We cannot support UIE mode if we do not have an IRQ line */ 1958 clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, ds1307->rtc->features); 1959 } 1960 1961 if (want_irq) { 1962 err = devm_request_threaded_irq(ds1307->dev, client->irq, NULL, 1963 chip->irq_handler ?: ds1307_irq, 1964 IRQF_SHARED | IRQF_ONESHOT, 1965 ds1307->name, ds1307); 1966 if (err) { 1967 client->irq = 0; 1968 device_set_wakeup_capable(ds1307->dev, false); 1969 clear_bit(RTC_FEATURE_ALARM, ds1307->rtc->features); 1970 dev_err(ds1307->dev, "unable to request IRQ!\n"); 1971 } else { 1972 dev_dbg(ds1307->dev, "got IRQ %d\n", client->irq); 1973 } 1974 } 1975 1976 ds1307->rtc->ops = chip->rtc_ops ?: &ds13xx_rtc_ops; 1977 err = ds1307_add_frequency_test(ds1307); 1978 if (err) 1979 return err; 1980 1981 err = devm_rtc_register_device(ds1307->rtc); 1982 if (err) 1983 return err; 1984 1985 if (chip->nvram_size) { 1986 struct nvmem_config nvmem_cfg = { 1987 .name = "ds1307_nvram", 1988 .word_size = 1, 1989 .stride = 1, 1990 .size = chip->nvram_size, 1991 .reg_read = ds1307_nvram_read, 1992 .reg_write = ds1307_nvram_write, 1993 .priv = ds1307, 1994 }; 1995 1996 devm_rtc_nvmem_register(ds1307->rtc, &nvmem_cfg); 1997 } 1998 1999 ds1307_hwmon_register(ds1307); 2000 ds1307_clks_register(ds1307); 2001 ds1307_wdt_register(ds1307); 2002 2003 return 0; 2004 2005 exit: 2006 return err; 2007 } 2008 2009 static struct i2c_driver ds1307_driver = { 2010 .driver = { 2011 .name = "rtc-ds1307", 2012 .of_match_table = ds1307_of_match, 2013 }, 2014 .probe = ds1307_probe, 2015 .id_table = ds1307_id, 2016 }; 2017 2018 module_i2c_driver(ds1307_driver); 2019 2020 MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips"); 2021 MODULE_LICENSE("GPL"); 2022