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_OSCRUN BIT(5) 69 # define MCP794XX_BIT_VBATEN 0x08 70 #define DS1307_REG_MDAY 0x04 /* 01-31 */ 71 #define DS1307_REG_MONTH 0x05 /* 01-12 */ 72 # define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */ 73 #define DS1307_REG_YEAR 0x06 /* 00-99 */ 74 75 /* 76 * Other registers (control, status, alarms, trickle charge, NVRAM, etc) 77 * start at 7, and they differ a LOT. Only control and status matter for 78 * basic RTC date and time functionality; be careful using them. 79 */ 80 #define DS1307_REG_CONTROL 0x07 /* or ds1338 */ 81 # define DS1307_BIT_OUT 0x80 82 # define DS1338_BIT_OSF 0x20 83 # define DS1307_BIT_SQWE 0x10 84 # define DS1307_BIT_RS1 0x02 85 # define DS1307_BIT_RS0 0x01 86 #define DS1337_REG_CONTROL 0x0e 87 # define DS1337_BIT_nEOSC 0x80 88 # define DS1339_BIT_BBSQI 0x20 89 # define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */ 90 # define DS1337_BIT_RS2 0x10 91 # define DS1337_BIT_RS1 0x08 92 # define DS1337_BIT_INTCN 0x04 93 # define DS1337_BIT_A2IE 0x02 94 # define DS1337_BIT_A1IE 0x01 95 #define DS1340_REG_CONTROL 0x07 96 # define DS1340_BIT_OUT 0x80 97 # define DS1340_BIT_FT 0x40 98 # define DS1340_BIT_CALIB_SIGN 0x20 99 # define DS1340_M_CALIBRATION 0x1f 100 #define DS1340_REG_FLAG 0x09 101 # define DS1340_BIT_OSF 0x80 102 #define DS1337_REG_STATUS 0x0f 103 # define DS1337_BIT_OSF 0x80 104 # define DS3231_BIT_EN32KHZ 0x08 105 # define DS1337_BIT_A2I 0x02 106 # define DS1337_BIT_A1I 0x01 107 #define DS1339_REG_ALARM1_SECS 0x07 108 109 #define DS13XX_TRICKLE_CHARGER_MAGIC 0xa0 110 111 #define RX8025_REG_CTRL1 0x0e 112 # define RX8025_BIT_2412 0x20 113 #define RX8025_REG_CTRL2 0x0f 114 # define RX8025_BIT_PON 0x10 115 # define RX8025_BIT_VDET 0x40 116 # define RX8025_BIT_XST 0x20 117 118 #define RX8130_REG_ALARM_MIN 0x17 119 #define RX8130_REG_ALARM_HOUR 0x18 120 #define RX8130_REG_ALARM_WEEK_OR_DAY 0x19 121 #define RX8130_REG_EXTENSION 0x1c 122 #define RX8130_REG_EXTENSION_WADA BIT(3) 123 #define RX8130_REG_FLAG 0x1d 124 #define RX8130_REG_FLAG_VLF BIT(1) 125 #define RX8130_REG_FLAG_AF BIT(3) 126 #define RX8130_REG_CONTROL0 0x1e 127 #define RX8130_REG_CONTROL0_AIE BIT(3) 128 #define RX8130_REG_CONTROL1 0x1f 129 #define RX8130_REG_CONTROL1_INIEN BIT(4) 130 #define RX8130_REG_CONTROL1_CHGEN BIT(5) 131 132 #define MCP794XX_REG_CONTROL 0x07 133 # define MCP794XX_BIT_ALM0_EN 0x10 134 # define MCP794XX_BIT_ALM1_EN 0x20 135 #define MCP794XX_REG_ALARM0_BASE 0x0a 136 #define MCP794XX_REG_ALARM0_CTRL 0x0d 137 #define MCP794XX_REG_ALARM1_BASE 0x11 138 #define MCP794XX_REG_ALARM1_CTRL 0x14 139 # define MCP794XX_BIT_ALMX_IF BIT(3) 140 # define MCP794XX_BIT_ALMX_C0 BIT(4) 141 # define MCP794XX_BIT_ALMX_C1 BIT(5) 142 # define MCP794XX_BIT_ALMX_C2 BIT(6) 143 # define MCP794XX_BIT_ALMX_POL BIT(7) 144 # define MCP794XX_MSK_ALMX_MATCH (MCP794XX_BIT_ALMX_C0 | \ 145 MCP794XX_BIT_ALMX_C1 | \ 146 MCP794XX_BIT_ALMX_C2) 147 148 #define M41TXX_REG_CONTROL 0x07 149 # define M41TXX_BIT_OUT BIT(7) 150 # define M41TXX_BIT_FT BIT(6) 151 # define M41TXX_BIT_CALIB_SIGN BIT(5) 152 # define M41TXX_M_CALIBRATION GENMASK(4, 0) 153 154 #define DS1388_REG_WDOG_HUN_SECS 0x08 155 #define DS1388_REG_WDOG_SECS 0x09 156 #define DS1388_REG_FLAG 0x0b 157 # define DS1388_BIT_WF BIT(6) 158 # define DS1388_BIT_OSF BIT(7) 159 #define DS1388_REG_CONTROL 0x0c 160 # define DS1388_BIT_RST BIT(0) 161 # define DS1388_BIT_WDE BIT(1) 162 # define DS1388_BIT_nEOSC BIT(7) 163 164 /* negative offset step is -2.034ppm */ 165 #define M41TXX_NEG_OFFSET_STEP_PPB 2034 166 /* positive offset step is +4.068ppm */ 167 #define M41TXX_POS_OFFSET_STEP_PPB 4068 168 /* Min and max values supported with 'offset' interface by M41TXX */ 169 #define M41TXX_MIN_OFFSET ((-31) * M41TXX_NEG_OFFSET_STEP_PPB) 170 #define M41TXX_MAX_OFFSET ((31) * M41TXX_POS_OFFSET_STEP_PPB) 171 172 struct ds1307 { 173 enum ds_type type; 174 struct device *dev; 175 struct regmap *regmap; 176 const char *name; 177 struct rtc_device *rtc; 178 #ifdef CONFIG_COMMON_CLK 179 struct clk_hw clks[2]; 180 #endif 181 }; 182 183 struct chip_desc { 184 unsigned alarm:1; 185 u16 nvram_offset; 186 u16 nvram_size; 187 u8 offset; /* register's offset */ 188 u8 century_reg; 189 u8 century_enable_bit; 190 u8 century_bit; 191 u8 bbsqi_bit; 192 irq_handler_t irq_handler; 193 const struct rtc_class_ops *rtc_ops; 194 u16 trickle_charger_reg; 195 u8 (*do_trickle_setup)(struct ds1307 *, u32, 196 bool); 197 /* Does the RTC require trickle-resistor-ohms to select the value of 198 * the resistor between Vcc and Vbackup? 199 */ 200 bool requires_trickle_resistor; 201 /* Some RTC's batteries and supercaps were charged by default, others 202 * allow charging but were not configured previously to do so. 203 * Remember this behavior to stay backwards compatible. 204 */ 205 bool charge_default; 206 }; 207 208 static const struct chip_desc chips[last_ds_type]; 209 210 static int ds1307_get_time(struct device *dev, struct rtc_time *t) 211 { 212 struct ds1307 *ds1307 = dev_get_drvdata(dev); 213 int tmp, ret; 214 const struct chip_desc *chip = &chips[ds1307->type]; 215 u8 regs[7]; 216 217 if (ds1307->type == rx_8130) { 218 unsigned int regflag; 219 ret = regmap_read(ds1307->regmap, RX8130_REG_FLAG, ®flag); 220 if (ret) { 221 dev_err(dev, "%s error %d\n", "read", ret); 222 return ret; 223 } 224 225 if (regflag & RX8130_REG_FLAG_VLF) { 226 dev_warn_once(dev, "oscillator failed, set time!\n"); 227 return -EINVAL; 228 } 229 } 230 231 /* read the RTC date and time registers all at once */ 232 ret = regmap_bulk_read(ds1307->regmap, chip->offset, regs, 233 sizeof(regs)); 234 if (ret) { 235 dev_err(dev, "%s error %d\n", "read", ret); 236 return ret; 237 } 238 239 dev_dbg(dev, "%s: %7ph\n", "read", regs); 240 241 /* if oscillator fail bit is set, no data can be trusted */ 242 if (ds1307->type == m41t0 && 243 regs[DS1307_REG_MIN] & M41T0_BIT_OF) { 244 dev_warn_once(dev, "oscillator failed, set time!\n"); 245 return -EINVAL; 246 } else if (ds1307->type == mcp794xx && 247 !(regs[DS1307_REG_WDAY] & MCP794XX_BIT_OSCRUN)) { 248 dev_warn_once(dev, "oscillator failed, set time!\n"); 249 return -EINVAL; 250 } 251 252 tmp = regs[DS1307_REG_SECS]; 253 switch (ds1307->type) { 254 case ds_1307: 255 case m41t0: 256 case m41t00: 257 case m41t11: 258 if (tmp & DS1307_BIT_CH) 259 return -EINVAL; 260 break; 261 case ds_1308: 262 case ds_1338: 263 if (tmp & DS1307_BIT_CH) 264 return -EINVAL; 265 266 ret = regmap_read(ds1307->regmap, DS1307_REG_CONTROL, &tmp); 267 if (ret) 268 return ret; 269 if (tmp & DS1338_BIT_OSF) 270 return -EINVAL; 271 break; 272 case ds_1340: 273 if (tmp & DS1340_BIT_nEOSC) 274 return -EINVAL; 275 276 ret = regmap_read(ds1307->regmap, DS1340_REG_FLAG, &tmp); 277 if (ret) 278 return ret; 279 if (tmp & DS1340_BIT_OSF) 280 return -EINVAL; 281 break; 282 case ds_1341: 283 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &tmp); 284 if (ret) 285 return ret; 286 if (tmp & DS1337_BIT_OSF) 287 return -EINVAL; 288 break; 289 case ds_1388: 290 ret = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &tmp); 291 if (ret) 292 return ret; 293 if (tmp & DS1388_BIT_OSF) 294 return -EINVAL; 295 break; 296 case mcp794xx: 297 if (!(tmp & MCP794XX_BIT_ST)) 298 return -EINVAL; 299 300 break; 301 default: 302 break; 303 } 304 305 t->tm_sec = bcd2bin(regs[DS1307_REG_SECS] & 0x7f); 306 t->tm_min = bcd2bin(regs[DS1307_REG_MIN] & 0x7f); 307 tmp = regs[DS1307_REG_HOUR] & 0x3f; 308 t->tm_hour = bcd2bin(tmp); 309 /* rx8130 is bit position, not BCD */ 310 if (ds1307->type == rx_8130) 311 t->tm_wday = fls(regs[DS1307_REG_WDAY] & 0x7f); 312 else 313 t->tm_wday = bcd2bin(regs[DS1307_REG_WDAY] & 0x07) - 1; 314 t->tm_mday = bcd2bin(regs[DS1307_REG_MDAY] & 0x3f); 315 tmp = regs[DS1307_REG_MONTH] & 0x1f; 316 t->tm_mon = bcd2bin(tmp) - 1; 317 t->tm_year = bcd2bin(regs[DS1307_REG_YEAR]) + 100; 318 319 if (regs[chip->century_reg] & chip->century_bit && 320 IS_ENABLED(CONFIG_RTC_DRV_DS1307_CENTURY)) 321 t->tm_year += 100; 322 323 dev_dbg(dev, "%s secs=%d, mins=%d, " 324 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n", 325 "read", t->tm_sec, t->tm_min, 326 t->tm_hour, t->tm_mday, 327 t->tm_mon, t->tm_year, t->tm_wday); 328 329 return 0; 330 } 331 332 static int ds1307_set_time(struct device *dev, struct rtc_time *t) 333 { 334 struct ds1307 *ds1307 = dev_get_drvdata(dev); 335 const struct chip_desc *chip = &chips[ds1307->type]; 336 int result; 337 int tmp; 338 u8 regs[7]; 339 340 dev_dbg(dev, "%s secs=%d, mins=%d, " 341 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n", 342 "write", t->tm_sec, t->tm_min, 343 t->tm_hour, t->tm_mday, 344 t->tm_mon, t->tm_year, t->tm_wday); 345 346 if (t->tm_year < 100) 347 return -EINVAL; 348 349 #ifdef CONFIG_RTC_DRV_DS1307_CENTURY 350 if (t->tm_year > (chip->century_bit ? 299 : 199)) 351 return -EINVAL; 352 #else 353 if (t->tm_year > 199) 354 return -EINVAL; 355 #endif 356 357 regs[DS1307_REG_SECS] = bin2bcd(t->tm_sec); 358 regs[DS1307_REG_MIN] = bin2bcd(t->tm_min); 359 regs[DS1307_REG_HOUR] = bin2bcd(t->tm_hour); 360 /* rx8130 is bit position, not BCD */ 361 if (ds1307->type == rx_8130) 362 regs[DS1307_REG_WDAY] = 1 << t->tm_wday; 363 else 364 regs[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1); 365 regs[DS1307_REG_MDAY] = bin2bcd(t->tm_mday); 366 regs[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1); 367 368 /* assume 20YY not 19YY */ 369 tmp = t->tm_year % 100; 370 regs[DS1307_REG_YEAR] = bin2bcd(tmp); 371 372 if (chip->century_enable_bit) 373 regs[chip->century_reg] |= chip->century_enable_bit; 374 if (t->tm_year > 199 && chip->century_bit) 375 regs[chip->century_reg] |= chip->century_bit; 376 377 switch (ds1307->type) { 378 case ds_1308: 379 case ds_1338: 380 regmap_update_bits(ds1307->regmap, DS1307_REG_CONTROL, 381 DS1338_BIT_OSF, 0); 382 break; 383 case ds_1340: 384 regmap_update_bits(ds1307->regmap, DS1340_REG_FLAG, 385 DS1340_BIT_OSF, 0); 386 break; 387 case ds_1341: 388 regmap_update_bits(ds1307->regmap, DS1337_REG_STATUS, 389 DS1337_BIT_OSF, 0); 390 break; 391 case ds_1388: 392 regmap_update_bits(ds1307->regmap, DS1388_REG_FLAG, 393 DS1388_BIT_OSF, 0); 394 break; 395 case mcp794xx: 396 /* 397 * these bits were cleared when preparing the date/time 398 * values and need to be set again before writing the 399 * regsfer out to the device. 400 */ 401 regs[DS1307_REG_SECS] |= MCP794XX_BIT_ST; 402 regs[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN; 403 break; 404 default: 405 break; 406 } 407 408 dev_dbg(dev, "%s: %7ph\n", "write", regs); 409 410 result = regmap_bulk_write(ds1307->regmap, chip->offset, regs, 411 sizeof(regs)); 412 if (result) { 413 dev_err(dev, "%s error %d\n", "write", result); 414 return result; 415 } 416 417 if (ds1307->type == rx_8130) { 418 /* clear Voltage Loss Flag as data is available now */ 419 result = regmap_write(ds1307->regmap, RX8130_REG_FLAG, 420 ~(u8)RX8130_REG_FLAG_VLF); 421 if (result) { 422 dev_err(dev, "%s error %d\n", "write", result); 423 return result; 424 } 425 } 426 427 return 0; 428 } 429 430 static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t) 431 { 432 struct ds1307 *ds1307 = dev_get_drvdata(dev); 433 int ret; 434 u8 regs[9]; 435 436 /* read all ALARM1, ALARM2, and status registers at once */ 437 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, 438 regs, sizeof(regs)); 439 if (ret) { 440 dev_err(dev, "%s error %d\n", "alarm read", ret); 441 return ret; 442 } 443 444 dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read", 445 ®s[0], ®s[4], ®s[7]); 446 447 /* 448 * report alarm time (ALARM1); assume 24 hour and day-of-month modes, 449 * and that all four fields are checked matches 450 */ 451 t->time.tm_sec = bcd2bin(regs[0] & 0x7f); 452 t->time.tm_min = bcd2bin(regs[1] & 0x7f); 453 t->time.tm_hour = bcd2bin(regs[2] & 0x3f); 454 t->time.tm_mday = bcd2bin(regs[3] & 0x3f); 455 456 /* ... and status */ 457 t->enabled = !!(regs[7] & DS1337_BIT_A1IE); 458 t->pending = !!(regs[8] & DS1337_BIT_A1I); 459 460 dev_dbg(dev, "%s secs=%d, mins=%d, " 461 "hours=%d, mday=%d, enabled=%d, pending=%d\n", 462 "alarm read", t->time.tm_sec, t->time.tm_min, 463 t->time.tm_hour, t->time.tm_mday, 464 t->enabled, t->pending); 465 466 return 0; 467 } 468 469 static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t) 470 { 471 struct ds1307 *ds1307 = dev_get_drvdata(dev); 472 unsigned char regs[9]; 473 u8 control, status; 474 int ret; 475 476 dev_dbg(dev, "%s secs=%d, mins=%d, " 477 "hours=%d, mday=%d, enabled=%d, pending=%d\n", 478 "alarm set", t->time.tm_sec, t->time.tm_min, 479 t->time.tm_hour, t->time.tm_mday, 480 t->enabled, t->pending); 481 482 /* read current status of both alarms and the chip */ 483 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs, 484 sizeof(regs)); 485 if (ret) { 486 dev_err(dev, "%s error %d\n", "alarm write", ret); 487 return ret; 488 } 489 control = regs[7]; 490 status = regs[8]; 491 492 dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)", 493 ®s[0], ®s[4], control, status); 494 495 /* set ALARM1, using 24 hour and day-of-month modes */ 496 regs[0] = bin2bcd(t->time.tm_sec); 497 regs[1] = bin2bcd(t->time.tm_min); 498 regs[2] = bin2bcd(t->time.tm_hour); 499 regs[3] = bin2bcd(t->time.tm_mday); 500 501 /* set ALARM2 to non-garbage */ 502 regs[4] = 0; 503 regs[5] = 0; 504 regs[6] = 0; 505 506 /* disable alarms */ 507 regs[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE); 508 regs[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I); 509 510 ret = regmap_bulk_write(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs, 511 sizeof(regs)); 512 if (ret) { 513 dev_err(dev, "can't set alarm time\n"); 514 return ret; 515 } 516 517 /* optionally enable ALARM1 */ 518 if (t->enabled) { 519 dev_dbg(dev, "alarm IRQ armed\n"); 520 regs[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */ 521 regmap_write(ds1307->regmap, DS1337_REG_CONTROL, regs[7]); 522 } 523 524 return 0; 525 } 526 527 static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled) 528 { 529 struct ds1307 *ds1307 = dev_get_drvdata(dev); 530 531 return regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL, 532 DS1337_BIT_A1IE, 533 enabled ? DS1337_BIT_A1IE : 0); 534 } 535 536 static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307, u32 ohms, bool diode) 537 { 538 u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE : 539 DS1307_TRICKLE_CHARGER_NO_DIODE; 540 541 setup |= DS13XX_TRICKLE_CHARGER_MAGIC; 542 543 switch (ohms) { 544 case 250: 545 setup |= DS1307_TRICKLE_CHARGER_250_OHM; 546 break; 547 case 2000: 548 setup |= DS1307_TRICKLE_CHARGER_2K_OHM; 549 break; 550 case 4000: 551 setup |= DS1307_TRICKLE_CHARGER_4K_OHM; 552 break; 553 default: 554 dev_warn(ds1307->dev, 555 "Unsupported ohm value %u in dt\n", ohms); 556 return 0; 557 } 558 return setup; 559 } 560 561 static u8 do_trickle_setup_rx8130(struct ds1307 *ds1307, u32 ohms, bool diode) 562 { 563 /* make sure that the backup battery is enabled */ 564 u8 setup = RX8130_REG_CONTROL1_INIEN; 565 if (diode) 566 setup |= RX8130_REG_CONTROL1_CHGEN; 567 568 return setup; 569 } 570 571 static irqreturn_t rx8130_irq(int irq, void *dev_id) 572 { 573 struct ds1307 *ds1307 = dev_id; 574 u8 ctl[3]; 575 int ret; 576 577 rtc_lock(ds1307->rtc); 578 579 /* Read control registers. */ 580 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 581 sizeof(ctl)); 582 if (ret < 0) 583 goto out; 584 if (!(ctl[1] & RX8130_REG_FLAG_AF)) 585 goto out; 586 ctl[1] &= ~RX8130_REG_FLAG_AF; 587 ctl[2] &= ~RX8130_REG_CONTROL0_AIE; 588 589 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 590 sizeof(ctl)); 591 if (ret < 0) 592 goto out; 593 594 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); 595 596 out: 597 rtc_unlock(ds1307->rtc); 598 599 return IRQ_HANDLED; 600 } 601 602 static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t) 603 { 604 struct ds1307 *ds1307 = dev_get_drvdata(dev); 605 u8 ald[3], ctl[3]; 606 int ret; 607 608 /* Read alarm registers. */ 609 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_ALARM_MIN, ald, 610 sizeof(ald)); 611 if (ret < 0) 612 return ret; 613 614 /* Read control registers. */ 615 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 616 sizeof(ctl)); 617 if (ret < 0) 618 return ret; 619 620 t->enabled = !!(ctl[2] & RX8130_REG_CONTROL0_AIE); 621 t->pending = !!(ctl[1] & RX8130_REG_FLAG_AF); 622 623 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */ 624 t->time.tm_sec = -1; 625 t->time.tm_min = bcd2bin(ald[0] & 0x7f); 626 t->time.tm_hour = bcd2bin(ald[1] & 0x7f); 627 t->time.tm_wday = -1; 628 t->time.tm_mday = bcd2bin(ald[2] & 0x7f); 629 t->time.tm_mon = -1; 630 t->time.tm_year = -1; 631 t->time.tm_yday = -1; 632 t->time.tm_isdst = -1; 633 634 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d enabled=%d\n", 635 __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour, 636 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled); 637 638 return 0; 639 } 640 641 static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t) 642 { 643 struct ds1307 *ds1307 = dev_get_drvdata(dev); 644 u8 ald[3], ctl[3]; 645 int ret; 646 647 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d " 648 "enabled=%d pending=%d\n", __func__, 649 t->time.tm_sec, t->time.tm_min, t->time.tm_hour, 650 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, 651 t->enabled, t->pending); 652 653 /* Read control registers. */ 654 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 655 sizeof(ctl)); 656 if (ret < 0) 657 return ret; 658 659 ctl[0] &= RX8130_REG_EXTENSION_WADA; 660 ctl[1] &= ~RX8130_REG_FLAG_AF; 661 ctl[2] &= ~RX8130_REG_CONTROL0_AIE; 662 663 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl, 664 sizeof(ctl)); 665 if (ret < 0) 666 return ret; 667 668 /* Hardware alarm precision is 1 minute! */ 669 ald[0] = bin2bcd(t->time.tm_min); 670 ald[1] = bin2bcd(t->time.tm_hour); 671 ald[2] = bin2bcd(t->time.tm_mday); 672 673 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_ALARM_MIN, ald, 674 sizeof(ald)); 675 if (ret < 0) 676 return ret; 677 678 if (!t->enabled) 679 return 0; 680 681 ctl[2] |= RX8130_REG_CONTROL0_AIE; 682 683 return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, ctl[2]); 684 } 685 686 static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled) 687 { 688 struct ds1307 *ds1307 = dev_get_drvdata(dev); 689 int ret, reg; 690 691 ret = regmap_read(ds1307->regmap, RX8130_REG_CONTROL0, ®); 692 if (ret < 0) 693 return ret; 694 695 if (enabled) 696 reg |= RX8130_REG_CONTROL0_AIE; 697 else 698 reg &= ~RX8130_REG_CONTROL0_AIE; 699 700 return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, reg); 701 } 702 703 static irqreturn_t mcp794xx_irq(int irq, void *dev_id) 704 { 705 struct ds1307 *ds1307 = dev_id; 706 struct mutex *lock = &ds1307->rtc->ops_lock; 707 int reg, ret; 708 709 mutex_lock(lock); 710 711 /* Check and clear alarm 0 interrupt flag. */ 712 ret = regmap_read(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, ®); 713 if (ret) 714 goto out; 715 if (!(reg & MCP794XX_BIT_ALMX_IF)) 716 goto out; 717 reg &= ~MCP794XX_BIT_ALMX_IF; 718 ret = regmap_write(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, reg); 719 if (ret) 720 goto out; 721 722 /* Disable alarm 0. */ 723 ret = regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL, 724 MCP794XX_BIT_ALM0_EN, 0); 725 if (ret) 726 goto out; 727 728 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); 729 730 out: 731 mutex_unlock(lock); 732 733 return IRQ_HANDLED; 734 } 735 736 static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t) 737 { 738 struct ds1307 *ds1307 = dev_get_drvdata(dev); 739 u8 regs[10]; 740 int ret; 741 742 /* Read control and alarm 0 registers. */ 743 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs, 744 sizeof(regs)); 745 if (ret) 746 return ret; 747 748 t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN); 749 750 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */ 751 t->time.tm_sec = bcd2bin(regs[3] & 0x7f); 752 t->time.tm_min = bcd2bin(regs[4] & 0x7f); 753 t->time.tm_hour = bcd2bin(regs[5] & 0x3f); 754 t->time.tm_wday = bcd2bin(regs[6] & 0x7) - 1; 755 t->time.tm_mday = bcd2bin(regs[7] & 0x3f); 756 t->time.tm_mon = bcd2bin(regs[8] & 0x1f) - 1; 757 t->time.tm_year = -1; 758 t->time.tm_yday = -1; 759 t->time.tm_isdst = -1; 760 761 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d " 762 "enabled=%d polarity=%d irq=%d match=%lu\n", __func__, 763 t->time.tm_sec, t->time.tm_min, t->time.tm_hour, 764 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled, 765 !!(regs[6] & MCP794XX_BIT_ALMX_POL), 766 !!(regs[6] & MCP794XX_BIT_ALMX_IF), 767 (regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4); 768 769 return 0; 770 } 771 772 /* 773 * We may have a random RTC weekday, therefore calculate alarm weekday based 774 * on current weekday we read from the RTC timekeeping regs 775 */ 776 static int mcp794xx_alm_weekday(struct device *dev, struct rtc_time *tm_alarm) 777 { 778 struct rtc_time tm_now; 779 int days_now, days_alarm, ret; 780 781 ret = ds1307_get_time(dev, &tm_now); 782 if (ret) 783 return ret; 784 785 days_now = div_s64(rtc_tm_to_time64(&tm_now), 24 * 60 * 60); 786 days_alarm = div_s64(rtc_tm_to_time64(tm_alarm), 24 * 60 * 60); 787 788 return (tm_now.tm_wday + days_alarm - days_now) % 7 + 1; 789 } 790 791 static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t) 792 { 793 struct ds1307 *ds1307 = dev_get_drvdata(dev); 794 unsigned char regs[10]; 795 int wday, ret; 796 797 wday = mcp794xx_alm_weekday(dev, &t->time); 798 if (wday < 0) 799 return wday; 800 801 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d " 802 "enabled=%d pending=%d\n", __func__, 803 t->time.tm_sec, t->time.tm_min, t->time.tm_hour, 804 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, 805 t->enabled, t->pending); 806 807 /* Read control and alarm 0 registers. */ 808 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs, 809 sizeof(regs)); 810 if (ret) 811 return ret; 812 813 /* Set alarm 0, using 24-hour and day-of-month modes. */ 814 regs[3] = bin2bcd(t->time.tm_sec); 815 regs[4] = bin2bcd(t->time.tm_min); 816 regs[5] = bin2bcd(t->time.tm_hour); 817 regs[6] = wday; 818 regs[7] = bin2bcd(t->time.tm_mday); 819 regs[8] = bin2bcd(t->time.tm_mon + 1); 820 821 /* Clear the alarm 0 interrupt flag. */ 822 regs[6] &= ~MCP794XX_BIT_ALMX_IF; 823 /* Set alarm match: second, minute, hour, day, date, month. */ 824 regs[6] |= MCP794XX_MSK_ALMX_MATCH; 825 /* Disable interrupt. We will not enable until completely programmed */ 826 regs[0] &= ~MCP794XX_BIT_ALM0_EN; 827 828 ret = regmap_bulk_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs, 829 sizeof(regs)); 830 if (ret) 831 return ret; 832 833 if (!t->enabled) 834 return 0; 835 regs[0] |= MCP794XX_BIT_ALM0_EN; 836 return regmap_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs[0]); 837 } 838 839 static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled) 840 { 841 struct ds1307 *ds1307 = dev_get_drvdata(dev); 842 843 return regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL, 844 MCP794XX_BIT_ALM0_EN, 845 enabled ? MCP794XX_BIT_ALM0_EN : 0); 846 } 847 848 static int m41txx_rtc_read_offset(struct device *dev, long *offset) 849 { 850 struct ds1307 *ds1307 = dev_get_drvdata(dev); 851 unsigned int ctrl_reg; 852 u8 val; 853 854 regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg); 855 856 val = ctrl_reg & M41TXX_M_CALIBRATION; 857 858 /* check if positive */ 859 if (ctrl_reg & M41TXX_BIT_CALIB_SIGN) 860 *offset = (val * M41TXX_POS_OFFSET_STEP_PPB); 861 else 862 *offset = -(val * M41TXX_NEG_OFFSET_STEP_PPB); 863 864 return 0; 865 } 866 867 static int m41txx_rtc_set_offset(struct device *dev, long offset) 868 { 869 struct ds1307 *ds1307 = dev_get_drvdata(dev); 870 unsigned int ctrl_reg; 871 872 if ((offset < M41TXX_MIN_OFFSET) || (offset > M41TXX_MAX_OFFSET)) 873 return -ERANGE; 874 875 if (offset >= 0) { 876 ctrl_reg = DIV_ROUND_CLOSEST(offset, 877 M41TXX_POS_OFFSET_STEP_PPB); 878 ctrl_reg |= M41TXX_BIT_CALIB_SIGN; 879 } else { 880 ctrl_reg = DIV_ROUND_CLOSEST(abs(offset), 881 M41TXX_NEG_OFFSET_STEP_PPB); 882 } 883 884 return regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, 885 M41TXX_M_CALIBRATION | M41TXX_BIT_CALIB_SIGN, 886 ctrl_reg); 887 } 888 889 #ifdef CONFIG_WATCHDOG_CORE 890 static int ds1388_wdt_start(struct watchdog_device *wdt_dev) 891 { 892 struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); 893 u8 regs[2]; 894 int ret; 895 896 ret = regmap_update_bits(ds1307->regmap, DS1388_REG_FLAG, 897 DS1388_BIT_WF, 0); 898 if (ret) 899 return ret; 900 901 ret = regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL, 902 DS1388_BIT_WDE | DS1388_BIT_RST, 0); 903 if (ret) 904 return ret; 905 906 /* 907 * watchdog timeouts are measured in seconds. So ignore hundredths of 908 * seconds field. 909 */ 910 regs[0] = 0; 911 regs[1] = bin2bcd(wdt_dev->timeout); 912 913 ret = regmap_bulk_write(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs, 914 sizeof(regs)); 915 if (ret) 916 return ret; 917 918 return regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL, 919 DS1388_BIT_WDE | DS1388_BIT_RST, 920 DS1388_BIT_WDE | DS1388_BIT_RST); 921 } 922 923 static int ds1388_wdt_stop(struct watchdog_device *wdt_dev) 924 { 925 struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); 926 927 return regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL, 928 DS1388_BIT_WDE | DS1388_BIT_RST, 0); 929 } 930 931 static int ds1388_wdt_ping(struct watchdog_device *wdt_dev) 932 { 933 struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); 934 u8 regs[2]; 935 936 return regmap_bulk_read(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs, 937 sizeof(regs)); 938 } 939 940 static int ds1388_wdt_set_timeout(struct watchdog_device *wdt_dev, 941 unsigned int val) 942 { 943 struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); 944 u8 regs[2]; 945 946 wdt_dev->timeout = val; 947 regs[0] = 0; 948 regs[1] = bin2bcd(wdt_dev->timeout); 949 950 return regmap_bulk_write(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs, 951 sizeof(regs)); 952 } 953 #endif 954 955 static const struct rtc_class_ops rx8130_rtc_ops = { 956 .read_time = ds1307_get_time, 957 .set_time = ds1307_set_time, 958 .read_alarm = rx8130_read_alarm, 959 .set_alarm = rx8130_set_alarm, 960 .alarm_irq_enable = rx8130_alarm_irq_enable, 961 }; 962 963 static const struct rtc_class_ops mcp794xx_rtc_ops = { 964 .read_time = ds1307_get_time, 965 .set_time = ds1307_set_time, 966 .read_alarm = mcp794xx_read_alarm, 967 .set_alarm = mcp794xx_set_alarm, 968 .alarm_irq_enable = mcp794xx_alarm_irq_enable, 969 }; 970 971 static const struct rtc_class_ops m41txx_rtc_ops = { 972 .read_time = ds1307_get_time, 973 .set_time = ds1307_set_time, 974 .read_alarm = ds1337_read_alarm, 975 .set_alarm = ds1337_set_alarm, 976 .alarm_irq_enable = ds1307_alarm_irq_enable, 977 .read_offset = m41txx_rtc_read_offset, 978 .set_offset = m41txx_rtc_set_offset, 979 }; 980 981 static const struct chip_desc chips[last_ds_type] = { 982 [ds_1307] = { 983 .nvram_offset = 8, 984 .nvram_size = 56, 985 }, 986 [ds_1308] = { 987 .nvram_offset = 8, 988 .nvram_size = 56, 989 }, 990 [ds_1337] = { 991 .alarm = 1, 992 .century_reg = DS1307_REG_MONTH, 993 .century_bit = DS1337_BIT_CENTURY, 994 }, 995 [ds_1338] = { 996 .nvram_offset = 8, 997 .nvram_size = 56, 998 }, 999 [ds_1339] = { 1000 .alarm = 1, 1001 .century_reg = DS1307_REG_MONTH, 1002 .century_bit = DS1337_BIT_CENTURY, 1003 .bbsqi_bit = DS1339_BIT_BBSQI, 1004 .trickle_charger_reg = 0x10, 1005 .do_trickle_setup = &do_trickle_setup_ds1339, 1006 .requires_trickle_resistor = true, 1007 .charge_default = true, 1008 }, 1009 [ds_1340] = { 1010 .century_reg = DS1307_REG_HOUR, 1011 .century_enable_bit = DS1340_BIT_CENTURY_EN, 1012 .century_bit = DS1340_BIT_CENTURY, 1013 .do_trickle_setup = &do_trickle_setup_ds1339, 1014 .trickle_charger_reg = 0x08, 1015 .requires_trickle_resistor = true, 1016 .charge_default = true, 1017 }, 1018 [ds_1341] = { 1019 .century_reg = DS1307_REG_MONTH, 1020 .century_bit = DS1337_BIT_CENTURY, 1021 }, 1022 [ds_1388] = { 1023 .offset = 1, 1024 .trickle_charger_reg = 0x0a, 1025 }, 1026 [ds_3231] = { 1027 .alarm = 1, 1028 .century_reg = DS1307_REG_MONTH, 1029 .century_bit = DS1337_BIT_CENTURY, 1030 .bbsqi_bit = DS3231_BIT_BBSQW, 1031 }, 1032 [rx_8130] = { 1033 .alarm = 1, 1034 /* this is battery backed SRAM */ 1035 .nvram_offset = 0x20, 1036 .nvram_size = 4, /* 32bit (4 word x 8 bit) */ 1037 .offset = 0x10, 1038 .irq_handler = rx8130_irq, 1039 .rtc_ops = &rx8130_rtc_ops, 1040 .trickle_charger_reg = RX8130_REG_CONTROL1, 1041 .do_trickle_setup = &do_trickle_setup_rx8130, 1042 }, 1043 [m41t0] = { 1044 .rtc_ops = &m41txx_rtc_ops, 1045 }, 1046 [m41t00] = { 1047 .rtc_ops = &m41txx_rtc_ops, 1048 }, 1049 [m41t11] = { 1050 /* this is battery backed SRAM */ 1051 .nvram_offset = 8, 1052 .nvram_size = 56, 1053 .rtc_ops = &m41txx_rtc_ops, 1054 }, 1055 [mcp794xx] = { 1056 .alarm = 1, 1057 /* this is battery backed SRAM */ 1058 .nvram_offset = 0x20, 1059 .nvram_size = 0x40, 1060 .irq_handler = mcp794xx_irq, 1061 .rtc_ops = &mcp794xx_rtc_ops, 1062 }, 1063 }; 1064 1065 static const struct i2c_device_id ds1307_id[] = { 1066 { "ds1307", ds_1307 }, 1067 { "ds1308", ds_1308 }, 1068 { "ds1337", ds_1337 }, 1069 { "ds1338", ds_1338 }, 1070 { "ds1339", ds_1339 }, 1071 { "ds1388", ds_1388 }, 1072 { "ds1340", ds_1340 }, 1073 { "ds1341", ds_1341 }, 1074 { "ds3231", ds_3231 }, 1075 { "m41t0", m41t0 }, 1076 { "m41t00", m41t00 }, 1077 { "m41t11", m41t11 }, 1078 { "mcp7940x", mcp794xx }, 1079 { "mcp7941x", mcp794xx }, 1080 { "pt7c4338", ds_1307 }, 1081 { "rx8025", rx_8025 }, 1082 { "isl12057", ds_1337 }, 1083 { "rx8130", rx_8130 }, 1084 { } 1085 }; 1086 MODULE_DEVICE_TABLE(i2c, ds1307_id); 1087 1088 static const struct of_device_id ds1307_of_match[] = { 1089 { 1090 .compatible = "dallas,ds1307", 1091 .data = (void *)ds_1307 1092 }, 1093 { 1094 .compatible = "dallas,ds1308", 1095 .data = (void *)ds_1308 1096 }, 1097 { 1098 .compatible = "dallas,ds1337", 1099 .data = (void *)ds_1337 1100 }, 1101 { 1102 .compatible = "dallas,ds1338", 1103 .data = (void *)ds_1338 1104 }, 1105 { 1106 .compatible = "dallas,ds1339", 1107 .data = (void *)ds_1339 1108 }, 1109 { 1110 .compatible = "dallas,ds1388", 1111 .data = (void *)ds_1388 1112 }, 1113 { 1114 .compatible = "dallas,ds1340", 1115 .data = (void *)ds_1340 1116 }, 1117 { 1118 .compatible = "dallas,ds1341", 1119 .data = (void *)ds_1341 1120 }, 1121 { 1122 .compatible = "maxim,ds3231", 1123 .data = (void *)ds_3231 1124 }, 1125 { 1126 .compatible = "st,m41t0", 1127 .data = (void *)m41t0 1128 }, 1129 { 1130 .compatible = "st,m41t00", 1131 .data = (void *)m41t00 1132 }, 1133 { 1134 .compatible = "st,m41t11", 1135 .data = (void *)m41t11 1136 }, 1137 { 1138 .compatible = "microchip,mcp7940x", 1139 .data = (void *)mcp794xx 1140 }, 1141 { 1142 .compatible = "microchip,mcp7941x", 1143 .data = (void *)mcp794xx 1144 }, 1145 { 1146 .compatible = "pericom,pt7c4338", 1147 .data = (void *)ds_1307 1148 }, 1149 { 1150 .compatible = "epson,rx8025", 1151 .data = (void *)rx_8025 1152 }, 1153 { 1154 .compatible = "isil,isl12057", 1155 .data = (void *)ds_1337 1156 }, 1157 { 1158 .compatible = "epson,rx8130", 1159 .data = (void *)rx_8130 1160 }, 1161 { } 1162 }; 1163 MODULE_DEVICE_TABLE(of, ds1307_of_match); 1164 1165 /* 1166 * The ds1337 and ds1339 both have two alarms, but we only use the first 1167 * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm 1168 * signal; ds1339 chips have only one alarm signal. 1169 */ 1170 static irqreturn_t ds1307_irq(int irq, void *dev_id) 1171 { 1172 struct ds1307 *ds1307 = dev_id; 1173 struct mutex *lock = &ds1307->rtc->ops_lock; 1174 int stat, ret; 1175 1176 mutex_lock(lock); 1177 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &stat); 1178 if (ret) 1179 goto out; 1180 1181 if (stat & DS1337_BIT_A1I) { 1182 stat &= ~DS1337_BIT_A1I; 1183 regmap_write(ds1307->regmap, DS1337_REG_STATUS, stat); 1184 1185 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL, 1186 DS1337_BIT_A1IE, 0); 1187 if (ret) 1188 goto out; 1189 1190 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); 1191 } 1192 1193 out: 1194 mutex_unlock(lock); 1195 1196 return IRQ_HANDLED; 1197 } 1198 1199 /*----------------------------------------------------------------------*/ 1200 1201 static const struct rtc_class_ops ds13xx_rtc_ops = { 1202 .read_time = ds1307_get_time, 1203 .set_time = ds1307_set_time, 1204 .read_alarm = ds1337_read_alarm, 1205 .set_alarm = ds1337_set_alarm, 1206 .alarm_irq_enable = ds1307_alarm_irq_enable, 1207 }; 1208 1209 static ssize_t frequency_test_store(struct device *dev, 1210 struct device_attribute *attr, 1211 const char *buf, size_t count) 1212 { 1213 struct ds1307 *ds1307 = dev_get_drvdata(dev->parent); 1214 bool freq_test_en; 1215 int ret; 1216 1217 ret = kstrtobool(buf, &freq_test_en); 1218 if (ret) { 1219 dev_err(dev, "Failed to store RTC Frequency Test attribute\n"); 1220 return ret; 1221 } 1222 1223 regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, M41TXX_BIT_FT, 1224 freq_test_en ? M41TXX_BIT_FT : 0); 1225 1226 return count; 1227 } 1228 1229 static ssize_t frequency_test_show(struct device *dev, 1230 struct device_attribute *attr, 1231 char *buf) 1232 { 1233 struct ds1307 *ds1307 = dev_get_drvdata(dev->parent); 1234 unsigned int ctrl_reg; 1235 1236 regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg); 1237 1238 return sysfs_emit(buf, (ctrl_reg & M41TXX_BIT_FT) ? "on\n" : "off\n"); 1239 } 1240 1241 static DEVICE_ATTR_RW(frequency_test); 1242 1243 static struct attribute *rtc_freq_test_attrs[] = { 1244 &dev_attr_frequency_test.attr, 1245 NULL, 1246 }; 1247 1248 static const struct attribute_group rtc_freq_test_attr_group = { 1249 .attrs = rtc_freq_test_attrs, 1250 }; 1251 1252 static int ds1307_add_frequency_test(struct ds1307 *ds1307) 1253 { 1254 int err; 1255 1256 switch (ds1307->type) { 1257 case m41t0: 1258 case m41t00: 1259 case m41t11: 1260 err = rtc_add_group(ds1307->rtc, &rtc_freq_test_attr_group); 1261 if (err) 1262 return err; 1263 break; 1264 default: 1265 break; 1266 } 1267 1268 return 0; 1269 } 1270 1271 /*----------------------------------------------------------------------*/ 1272 1273 static int ds1307_nvram_read(void *priv, unsigned int offset, void *val, 1274 size_t bytes) 1275 { 1276 struct ds1307 *ds1307 = priv; 1277 const struct chip_desc *chip = &chips[ds1307->type]; 1278 1279 return regmap_bulk_read(ds1307->regmap, chip->nvram_offset + offset, 1280 val, bytes); 1281 } 1282 1283 static int ds1307_nvram_write(void *priv, unsigned int offset, void *val, 1284 size_t bytes) 1285 { 1286 struct ds1307 *ds1307 = priv; 1287 const struct chip_desc *chip = &chips[ds1307->type]; 1288 1289 return regmap_bulk_write(ds1307->regmap, chip->nvram_offset + offset, 1290 val, bytes); 1291 } 1292 1293 /*----------------------------------------------------------------------*/ 1294 1295 static u8 ds1307_trickle_init(struct ds1307 *ds1307, 1296 const struct chip_desc *chip) 1297 { 1298 u32 ohms, chargeable; 1299 bool diode = chip->charge_default; 1300 1301 if (!chip->do_trickle_setup) 1302 return 0; 1303 1304 if (device_property_read_u32(ds1307->dev, "trickle-resistor-ohms", 1305 &ohms) && chip->requires_trickle_resistor) 1306 return 0; 1307 1308 /* aux-voltage-chargeable takes precedence over the deprecated 1309 * trickle-diode-disable 1310 */ 1311 if (!device_property_read_u32(ds1307->dev, "aux-voltage-chargeable", 1312 &chargeable)) { 1313 switch (chargeable) { 1314 case 0: 1315 diode = false; 1316 break; 1317 case 1: 1318 diode = true; 1319 break; 1320 default: 1321 dev_warn(ds1307->dev, 1322 "unsupported aux-voltage-chargeable value\n"); 1323 break; 1324 } 1325 } else if (device_property_read_bool(ds1307->dev, 1326 "trickle-diode-disable")) { 1327 diode = false; 1328 } 1329 1330 return chip->do_trickle_setup(ds1307, ohms, diode); 1331 } 1332 1333 /*----------------------------------------------------------------------*/ 1334 1335 #if IS_REACHABLE(CONFIG_HWMON) 1336 1337 /* 1338 * Temperature sensor support for ds3231 devices. 1339 */ 1340 1341 #define DS3231_REG_TEMPERATURE 0x11 1342 1343 /* 1344 * A user-initiated temperature conversion is not started by this function, 1345 * so the temperature is updated once every 64 seconds. 1346 */ 1347 static int ds3231_hwmon_read_temp(struct device *dev, s32 *mC) 1348 { 1349 struct ds1307 *ds1307 = dev_get_drvdata(dev); 1350 u8 temp_buf[2]; 1351 s16 temp; 1352 int ret; 1353 1354 ret = regmap_bulk_read(ds1307->regmap, DS3231_REG_TEMPERATURE, 1355 temp_buf, sizeof(temp_buf)); 1356 if (ret) 1357 return ret; 1358 /* 1359 * Temperature is represented as a 10-bit code with a resolution of 1360 * 0.25 degree celsius and encoded in two's complement format. 1361 */ 1362 temp = (temp_buf[0] << 8) | temp_buf[1]; 1363 temp >>= 6; 1364 *mC = temp * 250; 1365 1366 return 0; 1367 } 1368 1369 static ssize_t ds3231_hwmon_show_temp(struct device *dev, 1370 struct device_attribute *attr, char *buf) 1371 { 1372 int ret; 1373 s32 temp; 1374 1375 ret = ds3231_hwmon_read_temp(dev, &temp); 1376 if (ret) 1377 return ret; 1378 1379 return sprintf(buf, "%d\n", temp); 1380 } 1381 static SENSOR_DEVICE_ATTR(temp1_input, 0444, ds3231_hwmon_show_temp, 1382 NULL, 0); 1383 1384 static struct attribute *ds3231_hwmon_attrs[] = { 1385 &sensor_dev_attr_temp1_input.dev_attr.attr, 1386 NULL, 1387 }; 1388 ATTRIBUTE_GROUPS(ds3231_hwmon); 1389 1390 static void ds1307_hwmon_register(struct ds1307 *ds1307) 1391 { 1392 struct device *dev; 1393 1394 if (ds1307->type != ds_3231) 1395 return; 1396 1397 dev = devm_hwmon_device_register_with_groups(ds1307->dev, ds1307->name, 1398 ds1307, 1399 ds3231_hwmon_groups); 1400 if (IS_ERR(dev)) { 1401 dev_warn(ds1307->dev, "unable to register hwmon device %ld\n", 1402 PTR_ERR(dev)); 1403 } 1404 } 1405 1406 #else 1407 1408 static void ds1307_hwmon_register(struct ds1307 *ds1307) 1409 { 1410 } 1411 1412 #endif /* CONFIG_RTC_DRV_DS1307_HWMON */ 1413 1414 /*----------------------------------------------------------------------*/ 1415 1416 /* 1417 * Square-wave output support for DS3231 1418 * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3231.pdf 1419 */ 1420 #ifdef CONFIG_COMMON_CLK 1421 1422 enum { 1423 DS3231_CLK_SQW = 0, 1424 DS3231_CLK_32KHZ, 1425 }; 1426 1427 #define clk_sqw_to_ds1307(clk) \ 1428 container_of(clk, struct ds1307, clks[DS3231_CLK_SQW]) 1429 #define clk_32khz_to_ds1307(clk) \ 1430 container_of(clk, struct ds1307, clks[DS3231_CLK_32KHZ]) 1431 1432 static int ds3231_clk_sqw_rates[] = { 1433 1, 1434 1024, 1435 4096, 1436 8192, 1437 }; 1438 1439 static int ds1337_write_control(struct ds1307 *ds1307, u8 mask, u8 value) 1440 { 1441 struct mutex *lock = &ds1307->rtc->ops_lock; 1442 int ret; 1443 1444 mutex_lock(lock); 1445 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL, 1446 mask, value); 1447 mutex_unlock(lock); 1448 1449 return ret; 1450 } 1451 1452 static unsigned long ds3231_clk_sqw_recalc_rate(struct clk_hw *hw, 1453 unsigned long parent_rate) 1454 { 1455 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1456 int control, ret; 1457 int rate_sel = 0; 1458 1459 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control); 1460 if (ret) 1461 return ret; 1462 if (control & DS1337_BIT_RS1) 1463 rate_sel += 1; 1464 if (control & DS1337_BIT_RS2) 1465 rate_sel += 2; 1466 1467 return ds3231_clk_sqw_rates[rate_sel]; 1468 } 1469 1470 static int ds3231_clk_sqw_determine_rate(struct clk_hw *hw, 1471 struct clk_rate_request *req) 1472 { 1473 int i; 1474 1475 for (i = ARRAY_SIZE(ds3231_clk_sqw_rates) - 1; i >= 0; i--) { 1476 if (ds3231_clk_sqw_rates[i] <= req->rate) { 1477 req->rate = ds3231_clk_sqw_rates[i]; 1478 1479 return 0; 1480 } 1481 } 1482 1483 req->rate = ds3231_clk_sqw_rates[ARRAY_SIZE(ds3231_clk_sqw_rates) - 1]; 1484 1485 return 0; 1486 } 1487 1488 static int ds3231_clk_sqw_set_rate(struct clk_hw *hw, unsigned long rate, 1489 unsigned long parent_rate) 1490 { 1491 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1492 int control = 0; 1493 int rate_sel; 1494 1495 for (rate_sel = 0; rate_sel < ARRAY_SIZE(ds3231_clk_sqw_rates); 1496 rate_sel++) { 1497 if (ds3231_clk_sqw_rates[rate_sel] == rate) 1498 break; 1499 } 1500 1501 if (rate_sel == ARRAY_SIZE(ds3231_clk_sqw_rates)) 1502 return -EINVAL; 1503 1504 if (rate_sel & 1) 1505 control |= DS1337_BIT_RS1; 1506 if (rate_sel & 2) 1507 control |= DS1337_BIT_RS2; 1508 1509 return ds1337_write_control(ds1307, DS1337_BIT_RS1 | DS1337_BIT_RS2, 1510 control); 1511 } 1512 1513 static int ds3231_clk_sqw_prepare(struct clk_hw *hw) 1514 { 1515 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1516 1517 return ds1337_write_control(ds1307, DS1337_BIT_INTCN, 0); 1518 } 1519 1520 static void ds3231_clk_sqw_unprepare(struct clk_hw *hw) 1521 { 1522 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1523 1524 ds1337_write_control(ds1307, DS1337_BIT_INTCN, DS1337_BIT_INTCN); 1525 } 1526 1527 static int ds3231_clk_sqw_is_prepared(struct clk_hw *hw) 1528 { 1529 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); 1530 int control, ret; 1531 1532 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control); 1533 if (ret) 1534 return ret; 1535 1536 return !(control & DS1337_BIT_INTCN); 1537 } 1538 1539 static const struct clk_ops ds3231_clk_sqw_ops = { 1540 .prepare = ds3231_clk_sqw_prepare, 1541 .unprepare = ds3231_clk_sqw_unprepare, 1542 .is_prepared = ds3231_clk_sqw_is_prepared, 1543 .recalc_rate = ds3231_clk_sqw_recalc_rate, 1544 .determine_rate = ds3231_clk_sqw_determine_rate, 1545 .set_rate = ds3231_clk_sqw_set_rate, 1546 }; 1547 1548 static unsigned long ds3231_clk_32khz_recalc_rate(struct clk_hw *hw, 1549 unsigned long parent_rate) 1550 { 1551 return 32768; 1552 } 1553 1554 static int ds3231_clk_32khz_control(struct ds1307 *ds1307, bool enable) 1555 { 1556 struct mutex *lock = &ds1307->rtc->ops_lock; 1557 int ret; 1558 1559 mutex_lock(lock); 1560 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_STATUS, 1561 DS3231_BIT_EN32KHZ, 1562 enable ? DS3231_BIT_EN32KHZ : 0); 1563 mutex_unlock(lock); 1564 1565 return ret; 1566 } 1567 1568 static int ds3231_clk_32khz_prepare(struct clk_hw *hw) 1569 { 1570 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw); 1571 1572 return ds3231_clk_32khz_control(ds1307, true); 1573 } 1574 1575 static void ds3231_clk_32khz_unprepare(struct clk_hw *hw) 1576 { 1577 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw); 1578 1579 ds3231_clk_32khz_control(ds1307, false); 1580 } 1581 1582 static int ds3231_clk_32khz_is_prepared(struct clk_hw *hw) 1583 { 1584 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw); 1585 int status, ret; 1586 1587 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &status); 1588 if (ret) 1589 return ret; 1590 1591 return !!(status & DS3231_BIT_EN32KHZ); 1592 } 1593 1594 static const struct clk_ops ds3231_clk_32khz_ops = { 1595 .prepare = ds3231_clk_32khz_prepare, 1596 .unprepare = ds3231_clk_32khz_unprepare, 1597 .is_prepared = ds3231_clk_32khz_is_prepared, 1598 .recalc_rate = ds3231_clk_32khz_recalc_rate, 1599 }; 1600 1601 static const char *ds3231_clks_names[] = { 1602 [DS3231_CLK_SQW] = "ds3231_clk_sqw", 1603 [DS3231_CLK_32KHZ] = "ds3231_clk_32khz", 1604 }; 1605 1606 static struct clk_init_data ds3231_clks_init[] = { 1607 [DS3231_CLK_SQW] = { 1608 .ops = &ds3231_clk_sqw_ops, 1609 }, 1610 [DS3231_CLK_32KHZ] = { 1611 .ops = &ds3231_clk_32khz_ops, 1612 }, 1613 }; 1614 1615 static int ds3231_clks_register(struct ds1307 *ds1307) 1616 { 1617 struct device_node *node = ds1307->dev->of_node; 1618 struct clk_onecell_data *onecell; 1619 int i; 1620 1621 onecell = devm_kzalloc(ds1307->dev, sizeof(*onecell), GFP_KERNEL); 1622 if (!onecell) 1623 return -ENOMEM; 1624 1625 onecell->clk_num = ARRAY_SIZE(ds3231_clks_init); 1626 onecell->clks = devm_kcalloc(ds1307->dev, onecell->clk_num, 1627 sizeof(onecell->clks[0]), GFP_KERNEL); 1628 if (!onecell->clks) 1629 return -ENOMEM; 1630 1631 /* optional override of the clockname */ 1632 device_property_read_string_array(ds1307->dev, "clock-output-names", 1633 ds3231_clks_names, 1634 ARRAY_SIZE(ds3231_clks_names)); 1635 1636 for (i = 0; i < ARRAY_SIZE(ds3231_clks_init); i++) { 1637 struct clk_init_data init = ds3231_clks_init[i]; 1638 1639 /* 1640 * Interrupt signal due to alarm conditions and square-wave 1641 * output share same pin, so don't initialize both. 1642 */ 1643 if (i == DS3231_CLK_SQW && test_bit(RTC_FEATURE_ALARM, ds1307->rtc->features)) 1644 continue; 1645 1646 init.name = ds3231_clks_names[i]; 1647 ds1307->clks[i].init = &init; 1648 1649 onecell->clks[i] = devm_clk_register(ds1307->dev, 1650 &ds1307->clks[i]); 1651 if (IS_ERR(onecell->clks[i])) 1652 return PTR_ERR(onecell->clks[i]); 1653 } 1654 1655 if (node) 1656 of_clk_add_provider(node, of_clk_src_onecell_get, onecell); 1657 1658 return 0; 1659 } 1660 1661 static void ds1307_clks_register(struct ds1307 *ds1307) 1662 { 1663 int ret; 1664 1665 if (ds1307->type != ds_3231) 1666 return; 1667 1668 ret = ds3231_clks_register(ds1307); 1669 if (ret) { 1670 dev_warn(ds1307->dev, "unable to register clock device %d\n", 1671 ret); 1672 } 1673 } 1674 1675 #else 1676 1677 static void ds1307_clks_register(struct ds1307 *ds1307) 1678 { 1679 } 1680 1681 #endif /* CONFIG_COMMON_CLK */ 1682 1683 #ifdef CONFIG_WATCHDOG_CORE 1684 static const struct watchdog_info ds1388_wdt_info = { 1685 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, 1686 .identity = "DS1388 watchdog", 1687 }; 1688 1689 static const struct watchdog_ops ds1388_wdt_ops = { 1690 .owner = THIS_MODULE, 1691 .start = ds1388_wdt_start, 1692 .stop = ds1388_wdt_stop, 1693 .ping = ds1388_wdt_ping, 1694 .set_timeout = ds1388_wdt_set_timeout, 1695 1696 }; 1697 1698 static void ds1307_wdt_register(struct ds1307 *ds1307) 1699 { 1700 struct watchdog_device *wdt; 1701 int err; 1702 int val; 1703 1704 if (ds1307->type != ds_1388) 1705 return; 1706 1707 wdt = devm_kzalloc(ds1307->dev, sizeof(*wdt), GFP_KERNEL); 1708 if (!wdt) 1709 return; 1710 1711 err = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &val); 1712 if (!err && val & DS1388_BIT_WF) 1713 wdt->bootstatus = WDIOF_CARDRESET; 1714 1715 wdt->info = &ds1388_wdt_info; 1716 wdt->ops = &ds1388_wdt_ops; 1717 wdt->timeout = 99; 1718 wdt->max_timeout = 99; 1719 wdt->min_timeout = 1; 1720 1721 watchdog_init_timeout(wdt, 0, ds1307->dev); 1722 watchdog_set_drvdata(wdt, ds1307); 1723 devm_watchdog_register_device(ds1307->dev, wdt); 1724 } 1725 #else 1726 static void ds1307_wdt_register(struct ds1307 *ds1307) 1727 { 1728 } 1729 #endif /* CONFIG_WATCHDOG_CORE */ 1730 1731 static const struct regmap_config regmap_config = { 1732 .reg_bits = 8, 1733 .val_bits = 8, 1734 }; 1735 1736 static int ds1307_probe(struct i2c_client *client) 1737 { 1738 const struct i2c_device_id *id = i2c_client_get_device_id(client); 1739 struct ds1307 *ds1307; 1740 const void *match; 1741 int err = -ENODEV; 1742 int tmp; 1743 const struct chip_desc *chip; 1744 bool want_irq; 1745 bool ds1307_can_wakeup_device = false; 1746 unsigned char regs[8]; 1747 struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev); 1748 u8 trickle_charger_setup = 0; 1749 1750 ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL); 1751 if (!ds1307) 1752 return -ENOMEM; 1753 1754 dev_set_drvdata(&client->dev, ds1307); 1755 ds1307->dev = &client->dev; 1756 ds1307->name = client->name; 1757 1758 ds1307->regmap = devm_regmap_init_i2c(client, ®map_config); 1759 if (IS_ERR(ds1307->regmap)) { 1760 dev_err(ds1307->dev, "regmap allocation failed\n"); 1761 return PTR_ERR(ds1307->regmap); 1762 } 1763 1764 i2c_set_clientdata(client, ds1307); 1765 1766 match = device_get_match_data(&client->dev); 1767 if (match) { 1768 ds1307->type = (uintptr_t)match; 1769 chip = &chips[ds1307->type]; 1770 } else if (id) { 1771 chip = &chips[id->driver_data]; 1772 ds1307->type = id->driver_data; 1773 } else { 1774 return -ENODEV; 1775 } 1776 1777 want_irq = client->irq > 0 && chip->alarm; 1778 1779 if (!pdata) 1780 trickle_charger_setup = ds1307_trickle_init(ds1307, chip); 1781 else if (pdata->trickle_charger_setup) 1782 trickle_charger_setup = pdata->trickle_charger_setup; 1783 1784 if (trickle_charger_setup && chip->trickle_charger_reg) { 1785 dev_dbg(ds1307->dev, 1786 "writing trickle charger info 0x%x to 0x%x\n", 1787 trickle_charger_setup, chip->trickle_charger_reg); 1788 regmap_write(ds1307->regmap, chip->trickle_charger_reg, 1789 trickle_charger_setup); 1790 } 1791 1792 /* 1793 * For devices with no IRQ directly connected to the SoC, the RTC chip 1794 * can be forced as a wakeup source by stating that explicitly in 1795 * the device's .dts file using the "wakeup-source" boolean property. 1796 * If the "wakeup-source" property is set, don't request an IRQ. 1797 * This will guarantee the 'wakealarm' sysfs entry is available on the device, 1798 * if supported by the RTC. 1799 */ 1800 if (chip->alarm && device_property_read_bool(&client->dev, "wakeup-source")) 1801 ds1307_can_wakeup_device = true; 1802 1803 switch (ds1307->type) { 1804 case ds_1337: 1805 case ds_1339: 1806 case ds_1341: 1807 case ds_3231: 1808 /* get registers that the "rtc" read below won't read... */ 1809 err = regmap_bulk_read(ds1307->regmap, DS1337_REG_CONTROL, 1810 regs, 2); 1811 if (err) { 1812 dev_dbg(ds1307->dev, "read error %d\n", err); 1813 goto exit; 1814 } 1815 1816 /* oscillator off? turn it on, so clock can tick. */ 1817 if (regs[0] & DS1337_BIT_nEOSC) 1818 regs[0] &= ~DS1337_BIT_nEOSC; 1819 1820 /* 1821 * Using IRQ or defined as wakeup-source? 1822 * Disable the square wave and both alarms. 1823 * For some variants, be sure alarms can trigger when we're 1824 * running on Vbackup (BBSQI/BBSQW) 1825 */ 1826 if (want_irq || ds1307_can_wakeup_device) 1827 regs[0] |= DS1337_BIT_INTCN | chip->bbsqi_bit; 1828 1829 regmap_write(ds1307->regmap, DS1337_REG_CONTROL, 1830 regs[0]); 1831 1832 /* oscillator fault? warn */ 1833 if (regs[1] & DS1337_BIT_OSF) { 1834 dev_warn(ds1307->dev, "SET TIME!\n"); 1835 } 1836 break; 1837 1838 case rx_8025: 1839 err = regmap_bulk_read(ds1307->regmap, 1840 RX8025_REG_CTRL1 << 4 | 0x08, regs, 2); 1841 if (err) { 1842 dev_dbg(ds1307->dev, "read error %d\n", err); 1843 goto exit; 1844 } 1845 1846 /* oscillator off? turn it on, so clock can tick. */ 1847 if (!(regs[1] & RX8025_BIT_XST)) { 1848 regs[1] |= RX8025_BIT_XST; 1849 regmap_write(ds1307->regmap, 1850 RX8025_REG_CTRL2 << 4 | 0x08, 1851 regs[1]); 1852 dev_warn(ds1307->dev, 1853 "oscillator stop detected - SET TIME!\n"); 1854 } 1855 1856 if (regs[1] & RX8025_BIT_PON) { 1857 regs[1] &= ~RX8025_BIT_PON; 1858 regmap_write(ds1307->regmap, 1859 RX8025_REG_CTRL2 << 4 | 0x08, 1860 regs[1]); 1861 dev_warn(ds1307->dev, "power-on detected\n"); 1862 } 1863 1864 if (regs[1] & RX8025_BIT_VDET) { 1865 regs[1] &= ~RX8025_BIT_VDET; 1866 regmap_write(ds1307->regmap, 1867 RX8025_REG_CTRL2 << 4 | 0x08, 1868 regs[1]); 1869 dev_warn(ds1307->dev, "voltage drop detected\n"); 1870 } 1871 1872 /* make sure we are running in 24hour mode */ 1873 if (!(regs[0] & RX8025_BIT_2412)) { 1874 u8 hour; 1875 1876 /* switch to 24 hour mode */ 1877 regmap_write(ds1307->regmap, 1878 RX8025_REG_CTRL1 << 4 | 0x08, 1879 regs[0] | RX8025_BIT_2412); 1880 1881 err = regmap_bulk_read(ds1307->regmap, 1882 RX8025_REG_CTRL1 << 4 | 0x08, 1883 regs, 2); 1884 if (err) { 1885 dev_dbg(ds1307->dev, "read error %d\n", err); 1886 goto exit; 1887 } 1888 1889 /* correct hour */ 1890 hour = bcd2bin(regs[DS1307_REG_HOUR]); 1891 if (hour == 12) 1892 hour = 0; 1893 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM) 1894 hour += 12; 1895 1896 regmap_write(ds1307->regmap, 1897 DS1307_REG_HOUR << 4 | 0x08, hour); 1898 } 1899 break; 1900 case ds_1388: 1901 err = regmap_read(ds1307->regmap, DS1388_REG_CONTROL, &tmp); 1902 if (err) { 1903 dev_dbg(ds1307->dev, "read error %d\n", err); 1904 goto exit; 1905 } 1906 1907 /* oscillator off? turn it on, so clock can tick. */ 1908 if (tmp & DS1388_BIT_nEOSC) { 1909 tmp &= ~DS1388_BIT_nEOSC; 1910 regmap_write(ds1307->regmap, DS1388_REG_CONTROL, tmp); 1911 } 1912 break; 1913 default: 1914 break; 1915 } 1916 1917 /* read RTC registers */ 1918 err = regmap_bulk_read(ds1307->regmap, chip->offset, regs, 1919 sizeof(regs)); 1920 if (err) { 1921 dev_dbg(ds1307->dev, "read error %d\n", err); 1922 goto exit; 1923 } 1924 1925 if (ds1307->type == mcp794xx && 1926 !(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) { 1927 regmap_write(ds1307->regmap, DS1307_REG_WDAY, 1928 regs[DS1307_REG_WDAY] | 1929 MCP794XX_BIT_VBATEN); 1930 } 1931 1932 tmp = regs[DS1307_REG_HOUR]; 1933 switch (ds1307->type) { 1934 case ds_1340: 1935 case m41t0: 1936 case m41t00: 1937 case m41t11: 1938 /* 1939 * NOTE: ignores century bits; fix before deploying 1940 * systems that will run through year 2100. 1941 */ 1942 break; 1943 case rx_8025: 1944 break; 1945 default: 1946 if (!(tmp & DS1307_BIT_12HR)) 1947 break; 1948 1949 /* 1950 * Be sure we're in 24 hour mode. Multi-master systems 1951 * take note... 1952 */ 1953 tmp = bcd2bin(tmp & 0x1f); 1954 if (tmp == 12) 1955 tmp = 0; 1956 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM) 1957 tmp += 12; 1958 regmap_write(ds1307->regmap, chip->offset + DS1307_REG_HOUR, 1959 bin2bcd(tmp)); 1960 } 1961 1962 ds1307->rtc = devm_rtc_allocate_device(ds1307->dev); 1963 if (IS_ERR(ds1307->rtc)) 1964 return PTR_ERR(ds1307->rtc); 1965 1966 if (want_irq || ds1307_can_wakeup_device) 1967 device_set_wakeup_capable(ds1307->dev, true); 1968 else 1969 clear_bit(RTC_FEATURE_ALARM, ds1307->rtc->features); 1970 1971 if (ds1307_can_wakeup_device && !want_irq) { 1972 dev_info(ds1307->dev, 1973 "'wakeup-source' is set, request for an IRQ is disabled!\n"); 1974 /* We cannot support UIE mode if we do not have an IRQ line */ 1975 clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, ds1307->rtc->features); 1976 } 1977 1978 if (want_irq) { 1979 err = devm_request_threaded_irq(ds1307->dev, client->irq, NULL, 1980 chip->irq_handler ?: ds1307_irq, 1981 IRQF_SHARED | IRQF_ONESHOT, 1982 ds1307->name, ds1307); 1983 if (err) { 1984 client->irq = 0; 1985 device_set_wakeup_capable(ds1307->dev, false); 1986 clear_bit(RTC_FEATURE_ALARM, ds1307->rtc->features); 1987 dev_err(ds1307->dev, "unable to request IRQ!\n"); 1988 } else { 1989 dev_dbg(ds1307->dev, "got IRQ %d\n", client->irq); 1990 } 1991 } 1992 1993 ds1307->rtc->ops = chip->rtc_ops ?: &ds13xx_rtc_ops; 1994 err = ds1307_add_frequency_test(ds1307); 1995 if (err) 1996 return err; 1997 1998 err = devm_rtc_register_device(ds1307->rtc); 1999 if (err) 2000 return err; 2001 2002 if (chip->nvram_size) { 2003 struct nvmem_config nvmem_cfg = { 2004 .name = "ds1307_nvram", 2005 .word_size = 1, 2006 .stride = 1, 2007 .size = chip->nvram_size, 2008 .reg_read = ds1307_nvram_read, 2009 .reg_write = ds1307_nvram_write, 2010 .priv = ds1307, 2011 }; 2012 2013 devm_rtc_nvmem_register(ds1307->rtc, &nvmem_cfg); 2014 } 2015 2016 ds1307_hwmon_register(ds1307); 2017 ds1307_clks_register(ds1307); 2018 ds1307_wdt_register(ds1307); 2019 2020 return 0; 2021 2022 exit: 2023 return err; 2024 } 2025 2026 static struct i2c_driver ds1307_driver = { 2027 .driver = { 2028 .name = "rtc-ds1307", 2029 .of_match_table = ds1307_of_match, 2030 }, 2031 .probe = ds1307_probe, 2032 .id_table = ds1307_id, 2033 }; 2034 2035 module_i2c_driver(ds1307_driver); 2036 2037 MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips"); 2038 MODULE_LICENSE("GPL"); 2039