1 /* 2 * Intersil ISL1208 rtc class driver 3 * 4 * Copyright 2005,2006 Hebert Valerio Riedel <hvr@gnu.org> 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published by the 8 * Free Software Foundation; either version 2 of the License, or (at your 9 * option) any later version. 10 * 11 */ 12 13 #include <linux/bcd.h> 14 #include <linux/i2c.h> 15 #include <linux/module.h> 16 #include <linux/of_device.h> 17 #include <linux/of_irq.h> 18 #include <linux/rtc.h> 19 20 /* Register map */ 21 /* rtc section */ 22 #define ISL1208_REG_SC 0x00 23 #define ISL1208_REG_MN 0x01 24 #define ISL1208_REG_HR 0x02 25 #define ISL1208_REG_HR_MIL (1<<7) /* 24h/12h mode */ 26 #define ISL1208_REG_HR_PM (1<<5) /* PM/AM bit in 12h mode */ 27 #define ISL1208_REG_DT 0x03 28 #define ISL1208_REG_MO 0x04 29 #define ISL1208_REG_YR 0x05 30 #define ISL1208_REG_DW 0x06 31 #define ISL1208_RTC_SECTION_LEN 7 32 33 /* control/status section */ 34 #define ISL1208_REG_SR 0x07 35 #define ISL1208_REG_SR_ARST (1<<7) /* auto reset */ 36 #define ISL1208_REG_SR_XTOSCB (1<<6) /* crystal oscillator */ 37 #define ISL1208_REG_SR_WRTC (1<<4) /* write rtc */ 38 #define ISL1208_REG_SR_EVT (1<<3) /* event */ 39 #define ISL1208_REG_SR_ALM (1<<2) /* alarm */ 40 #define ISL1208_REG_SR_BAT (1<<1) /* battery */ 41 #define ISL1208_REG_SR_RTCF (1<<0) /* rtc fail */ 42 #define ISL1208_REG_INT 0x08 43 #define ISL1208_REG_INT_ALME (1<<6) /* alarm enable */ 44 #define ISL1208_REG_INT_IM (1<<7) /* interrupt/alarm mode */ 45 #define ISL1219_REG_EV 0x09 46 #define ISL1219_REG_EV_EVEN (1<<4) /* event detection enable */ 47 #define ISL1219_REG_EV_EVIENB (1<<7) /* event in pull-up disable */ 48 #define ISL1208_REG_ATR 0x0a 49 #define ISL1208_REG_DTR 0x0b 50 51 /* alarm section */ 52 #define ISL1208_REG_SCA 0x0c 53 #define ISL1208_REG_MNA 0x0d 54 #define ISL1208_REG_HRA 0x0e 55 #define ISL1208_REG_DTA 0x0f 56 #define ISL1208_REG_MOA 0x10 57 #define ISL1208_REG_DWA 0x11 58 #define ISL1208_ALARM_SECTION_LEN 6 59 60 /* user section */ 61 #define ISL1208_REG_USR1 0x12 62 #define ISL1208_REG_USR2 0x13 63 #define ISL1208_USR_SECTION_LEN 2 64 65 /* event section */ 66 #define ISL1219_REG_SCT 0x14 67 #define ISL1219_REG_MNT 0x15 68 #define ISL1219_REG_HRT 0x16 69 #define ISL1219_REG_DTT 0x17 70 #define ISL1219_REG_MOT 0x18 71 #define ISL1219_REG_YRT 0x19 72 #define ISL1219_EVT_SECTION_LEN 6 73 74 static struct i2c_driver isl1208_driver; 75 76 /* ISL1208 various variants */ 77 enum isl1208_id { 78 TYPE_ISL1208 = 0, 79 TYPE_ISL1209, 80 TYPE_ISL1218, 81 TYPE_ISL1219, 82 ISL_LAST_ID 83 }; 84 85 /* Chip capabilities table */ 86 static const struct isl1208_config { 87 const char name[8]; 88 unsigned int nvmem_length; 89 unsigned has_tamper:1; 90 unsigned has_timestamp:1; 91 } isl1208_configs[] = { 92 [TYPE_ISL1208] = { "isl1208", 2, false, false }, 93 [TYPE_ISL1209] = { "isl1209", 2, true, false }, 94 [TYPE_ISL1218] = { "isl1218", 8, false, false }, 95 [TYPE_ISL1219] = { "isl1219", 2, true, true }, 96 }; 97 98 static const struct i2c_device_id isl1208_id[] = { 99 { "isl1208", TYPE_ISL1208 }, 100 { "isl1209", TYPE_ISL1209 }, 101 { "isl1218", TYPE_ISL1218 }, 102 { "isl1219", TYPE_ISL1219 }, 103 { } 104 }; 105 MODULE_DEVICE_TABLE(i2c, isl1208_id); 106 107 static const struct of_device_id isl1208_of_match[] = { 108 { .compatible = "isil,isl1208", .data = &isl1208_configs[TYPE_ISL1208] }, 109 { .compatible = "isil,isl1209", .data = &isl1208_configs[TYPE_ISL1209] }, 110 { .compatible = "isil,isl1218", .data = &isl1208_configs[TYPE_ISL1218] }, 111 { .compatible = "isil,isl1219", .data = &isl1208_configs[TYPE_ISL1219] }, 112 { } 113 }; 114 MODULE_DEVICE_TABLE(of, isl1208_of_match); 115 116 /* Device state */ 117 struct isl1208_state { 118 struct nvmem_config nvmem_config; 119 struct rtc_device *rtc; 120 const struct isl1208_config *config; 121 }; 122 123 /* block read */ 124 static int 125 isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[], 126 unsigned len) 127 { 128 int ret; 129 130 WARN_ON(reg > ISL1219_REG_YRT); 131 WARN_ON(reg + len > ISL1219_REG_YRT + 1); 132 133 ret = i2c_smbus_read_i2c_block_data(client, reg, len, buf); 134 return (ret < 0) ? ret : 0; 135 } 136 137 /* block write */ 138 static int 139 isl1208_i2c_set_regs(struct i2c_client *client, u8 reg, u8 const buf[], 140 unsigned len) 141 { 142 int ret; 143 144 WARN_ON(reg > ISL1219_REG_YRT); 145 WARN_ON(reg + len > ISL1219_REG_YRT + 1); 146 147 ret = i2c_smbus_write_i2c_block_data(client, reg, len, buf); 148 return (ret < 0) ? ret : 0; 149 } 150 151 /* simple check to see whether we have a isl1208 */ 152 static int 153 isl1208_i2c_validate_client(struct i2c_client *client) 154 { 155 u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, }; 156 u8 zero_mask[ISL1208_RTC_SECTION_LEN] = { 157 0x80, 0x80, 0x40, 0xc0, 0xe0, 0x00, 0xf8 158 }; 159 int i; 160 int ret; 161 162 ret = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN); 163 if (ret < 0) 164 return ret; 165 166 for (i = 0; i < ISL1208_RTC_SECTION_LEN; ++i) { 167 if (regs[i] & zero_mask[i]) /* check if bits are cleared */ 168 return -ENODEV; 169 } 170 171 return 0; 172 } 173 174 static int 175 isl1208_i2c_get_sr(struct i2c_client *client) 176 { 177 return i2c_smbus_read_byte_data(client, ISL1208_REG_SR); 178 } 179 180 static int 181 isl1208_i2c_get_atr(struct i2c_client *client) 182 { 183 int atr = i2c_smbus_read_byte_data(client, ISL1208_REG_ATR); 184 if (atr < 0) 185 return atr; 186 187 /* The 6bit value in the ATR register controls the load 188 * capacitance C_load * in steps of 0.25pF 189 * 190 * bit (1<<5) of the ATR register is inverted 191 * 192 * C_load(ATR=0x20) = 4.50pF 193 * C_load(ATR=0x00) = 12.50pF 194 * C_load(ATR=0x1f) = 20.25pF 195 * 196 */ 197 198 atr &= 0x3f; /* mask out lsb */ 199 atr ^= 1 << 5; /* invert 6th bit */ 200 atr += 2 * 9; /* add offset of 4.5pF; unit[atr] = 0.25pF */ 201 202 return atr; 203 } 204 205 /* returns adjustment value + 100 */ 206 static int 207 isl1208_i2c_get_dtr(struct i2c_client *client) 208 { 209 int dtr = i2c_smbus_read_byte_data(client, ISL1208_REG_DTR); 210 if (dtr < 0) 211 return -EIO; 212 213 /* dtr encodes adjustments of {-60,-40,-20,0,20,40,60} ppm */ 214 dtr = ((dtr & 0x3) * 20) * (dtr & (1 << 2) ? -1 : 1); 215 216 return dtr + 100; 217 } 218 219 static int 220 isl1208_i2c_get_usr(struct i2c_client *client) 221 { 222 u8 buf[ISL1208_USR_SECTION_LEN] = { 0, }; 223 int ret; 224 225 ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1, buf, 226 ISL1208_USR_SECTION_LEN); 227 if (ret < 0) 228 return ret; 229 230 return (buf[1] << 8) | buf[0]; 231 } 232 233 static int 234 isl1208_i2c_set_usr(struct i2c_client *client, u16 usr) 235 { 236 u8 buf[ISL1208_USR_SECTION_LEN]; 237 238 buf[0] = usr & 0xff; 239 buf[1] = (usr >> 8) & 0xff; 240 241 return isl1208_i2c_set_regs(client, ISL1208_REG_USR1, buf, 242 ISL1208_USR_SECTION_LEN); 243 } 244 245 static int 246 isl1208_rtc_toggle_alarm(struct i2c_client *client, int enable) 247 { 248 int icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT); 249 250 if (icr < 0) { 251 dev_err(&client->dev, "%s: reading INT failed\n", __func__); 252 return icr; 253 } 254 255 if (enable) 256 icr |= ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM; 257 else 258 icr &= ~(ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM); 259 260 icr = i2c_smbus_write_byte_data(client, ISL1208_REG_INT, icr); 261 if (icr < 0) { 262 dev_err(&client->dev, "%s: writing INT failed\n", __func__); 263 return icr; 264 } 265 266 return 0; 267 } 268 269 static int 270 isl1208_rtc_proc(struct device *dev, struct seq_file *seq) 271 { 272 struct i2c_client *const client = to_i2c_client(dev); 273 int sr, dtr, atr, usr; 274 275 sr = isl1208_i2c_get_sr(client); 276 if (sr < 0) { 277 dev_err(&client->dev, "%s: reading SR failed\n", __func__); 278 return sr; 279 } 280 281 seq_printf(seq, "status_reg\t:%s%s%s%s%s%s (0x%.2x)\n", 282 (sr & ISL1208_REG_SR_RTCF) ? " RTCF" : "", 283 (sr & ISL1208_REG_SR_BAT) ? " BAT" : "", 284 (sr & ISL1208_REG_SR_ALM) ? " ALM" : "", 285 (sr & ISL1208_REG_SR_WRTC) ? " WRTC" : "", 286 (sr & ISL1208_REG_SR_XTOSCB) ? " XTOSCB" : "", 287 (sr & ISL1208_REG_SR_ARST) ? " ARST" : "", sr); 288 289 seq_printf(seq, "batt_status\t: %s\n", 290 (sr & ISL1208_REG_SR_RTCF) ? "bad" : "okay"); 291 292 dtr = isl1208_i2c_get_dtr(client); 293 if (dtr >= 0) 294 seq_printf(seq, "digital_trim\t: %d ppm\n", dtr - 100); 295 296 atr = isl1208_i2c_get_atr(client); 297 if (atr >= 0) 298 seq_printf(seq, "analog_trim\t: %d.%.2d pF\n", 299 atr >> 2, (atr & 0x3) * 25); 300 301 usr = isl1208_i2c_get_usr(client); 302 if (usr >= 0) 303 seq_printf(seq, "user_data\t: 0x%.4x\n", usr); 304 305 return 0; 306 } 307 308 static int 309 isl1208_i2c_read_time(struct i2c_client *client, struct rtc_time *tm) 310 { 311 int sr; 312 u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, }; 313 314 sr = isl1208_i2c_get_sr(client); 315 if (sr < 0) { 316 dev_err(&client->dev, "%s: reading SR failed\n", __func__); 317 return -EIO; 318 } 319 320 sr = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN); 321 if (sr < 0) { 322 dev_err(&client->dev, "%s: reading RTC section failed\n", 323 __func__); 324 return sr; 325 } 326 327 tm->tm_sec = bcd2bin(regs[ISL1208_REG_SC]); 328 tm->tm_min = bcd2bin(regs[ISL1208_REG_MN]); 329 330 /* HR field has a more complex interpretation */ 331 { 332 const u8 _hr = regs[ISL1208_REG_HR]; 333 if (_hr & ISL1208_REG_HR_MIL) /* 24h format */ 334 tm->tm_hour = bcd2bin(_hr & 0x3f); 335 else { 336 /* 12h format */ 337 tm->tm_hour = bcd2bin(_hr & 0x1f); 338 if (_hr & ISL1208_REG_HR_PM) /* PM flag set */ 339 tm->tm_hour += 12; 340 } 341 } 342 343 tm->tm_mday = bcd2bin(regs[ISL1208_REG_DT]); 344 tm->tm_mon = bcd2bin(regs[ISL1208_REG_MO]) - 1; /* rtc starts at 1 */ 345 tm->tm_year = bcd2bin(regs[ISL1208_REG_YR]) + 100; 346 tm->tm_wday = bcd2bin(regs[ISL1208_REG_DW]); 347 348 return 0; 349 } 350 351 static int 352 isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) 353 { 354 struct rtc_time *const tm = &alarm->time; 355 u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, }; 356 int icr, yr, sr = isl1208_i2c_get_sr(client); 357 358 if (sr < 0) { 359 dev_err(&client->dev, "%s: reading SR failed\n", __func__); 360 return sr; 361 } 362 363 sr = isl1208_i2c_read_regs(client, ISL1208_REG_SCA, regs, 364 ISL1208_ALARM_SECTION_LEN); 365 if (sr < 0) { 366 dev_err(&client->dev, "%s: reading alarm section failed\n", 367 __func__); 368 return sr; 369 } 370 371 /* MSB of each alarm register is an enable bit */ 372 tm->tm_sec = bcd2bin(regs[ISL1208_REG_SCA - ISL1208_REG_SCA] & 0x7f); 373 tm->tm_min = bcd2bin(regs[ISL1208_REG_MNA - ISL1208_REG_SCA] & 0x7f); 374 tm->tm_hour = bcd2bin(regs[ISL1208_REG_HRA - ISL1208_REG_SCA] & 0x3f); 375 tm->tm_mday = bcd2bin(regs[ISL1208_REG_DTA - ISL1208_REG_SCA] & 0x3f); 376 tm->tm_mon = 377 bcd2bin(regs[ISL1208_REG_MOA - ISL1208_REG_SCA] & 0x1f) - 1; 378 tm->tm_wday = bcd2bin(regs[ISL1208_REG_DWA - ISL1208_REG_SCA] & 0x03); 379 380 /* The alarm doesn't store the year so get it from the rtc section */ 381 yr = i2c_smbus_read_byte_data(client, ISL1208_REG_YR); 382 if (yr < 0) { 383 dev_err(&client->dev, "%s: reading RTC YR failed\n", __func__); 384 return yr; 385 } 386 tm->tm_year = bcd2bin(yr) + 100; 387 388 icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT); 389 if (icr < 0) { 390 dev_err(&client->dev, "%s: reading INT failed\n", __func__); 391 return icr; 392 } 393 alarm->enabled = !!(icr & ISL1208_REG_INT_ALME); 394 395 return 0; 396 } 397 398 static int 399 isl1208_i2c_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) 400 { 401 struct rtc_time *alarm_tm = &alarm->time; 402 u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, }; 403 const int offs = ISL1208_REG_SCA; 404 struct rtc_time rtc_tm; 405 int err, enable; 406 407 err = isl1208_i2c_read_time(client, &rtc_tm); 408 if (err) 409 return err; 410 411 /* If the alarm time is before the current time disable the alarm */ 412 if (!alarm->enabled || rtc_tm_sub(alarm_tm, &rtc_tm) <= 0) 413 enable = 0x00; 414 else 415 enable = 0x80; 416 417 /* Program the alarm and enable it for each setting */ 418 regs[ISL1208_REG_SCA - offs] = bin2bcd(alarm_tm->tm_sec) | enable; 419 regs[ISL1208_REG_MNA - offs] = bin2bcd(alarm_tm->tm_min) | enable; 420 regs[ISL1208_REG_HRA - offs] = bin2bcd(alarm_tm->tm_hour) | 421 ISL1208_REG_HR_MIL | enable; 422 423 regs[ISL1208_REG_DTA - offs] = bin2bcd(alarm_tm->tm_mday) | enable; 424 regs[ISL1208_REG_MOA - offs] = bin2bcd(alarm_tm->tm_mon + 1) | enable; 425 regs[ISL1208_REG_DWA - offs] = bin2bcd(alarm_tm->tm_wday & 7) | enable; 426 427 /* write ALARM registers */ 428 err = isl1208_i2c_set_regs(client, offs, regs, 429 ISL1208_ALARM_SECTION_LEN); 430 if (err < 0) { 431 dev_err(&client->dev, "%s: writing ALARM section failed\n", 432 __func__); 433 return err; 434 } 435 436 err = isl1208_rtc_toggle_alarm(client, enable); 437 if (err) 438 return err; 439 440 return 0; 441 } 442 443 static int 444 isl1208_rtc_read_time(struct device *dev, struct rtc_time *tm) 445 { 446 return isl1208_i2c_read_time(to_i2c_client(dev), tm); 447 } 448 449 static int 450 isl1208_i2c_set_time(struct i2c_client *client, struct rtc_time const *tm) 451 { 452 int sr; 453 u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, }; 454 455 /* The clock has an 8 bit wide bcd-coded register (they never learn) 456 * for the year. tm_year is an offset from 1900 and we are interested 457 * in the 2000-2099 range, so any value less than 100 is invalid. 458 */ 459 if (tm->tm_year < 100) 460 return -EINVAL; 461 462 regs[ISL1208_REG_SC] = bin2bcd(tm->tm_sec); 463 regs[ISL1208_REG_MN] = bin2bcd(tm->tm_min); 464 regs[ISL1208_REG_HR] = bin2bcd(tm->tm_hour) | ISL1208_REG_HR_MIL; 465 466 regs[ISL1208_REG_DT] = bin2bcd(tm->tm_mday); 467 regs[ISL1208_REG_MO] = bin2bcd(tm->tm_mon + 1); 468 regs[ISL1208_REG_YR] = bin2bcd(tm->tm_year - 100); 469 470 regs[ISL1208_REG_DW] = bin2bcd(tm->tm_wday & 7); 471 472 sr = isl1208_i2c_get_sr(client); 473 if (sr < 0) { 474 dev_err(&client->dev, "%s: reading SR failed\n", __func__); 475 return sr; 476 } 477 478 /* set WRTC */ 479 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, 480 sr | ISL1208_REG_SR_WRTC); 481 if (sr < 0) { 482 dev_err(&client->dev, "%s: writing SR failed\n", __func__); 483 return sr; 484 } 485 486 /* write RTC registers */ 487 sr = isl1208_i2c_set_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN); 488 if (sr < 0) { 489 dev_err(&client->dev, "%s: writing RTC section failed\n", 490 __func__); 491 return sr; 492 } 493 494 /* clear WRTC again */ 495 sr = isl1208_i2c_get_sr(client); 496 if (sr < 0) { 497 dev_err(&client->dev, "%s: reading SR failed\n", __func__); 498 return sr; 499 } 500 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, 501 sr & ~ISL1208_REG_SR_WRTC); 502 if (sr < 0) { 503 dev_err(&client->dev, "%s: writing SR failed\n", __func__); 504 return sr; 505 } 506 507 return 0; 508 } 509 510 511 static int 512 isl1208_rtc_set_time(struct device *dev, struct rtc_time *tm) 513 { 514 return isl1208_i2c_set_time(to_i2c_client(dev), tm); 515 } 516 517 static int 518 isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) 519 { 520 return isl1208_i2c_read_alarm(to_i2c_client(dev), alarm); 521 } 522 523 static int 524 isl1208_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) 525 { 526 return isl1208_i2c_set_alarm(to_i2c_client(dev), alarm); 527 } 528 529 static ssize_t timestamp0_store(struct device *dev, 530 struct device_attribute *attr, 531 const char *buf, size_t count) 532 { 533 struct i2c_client *client = to_i2c_client(dev->parent); 534 int sr; 535 536 sr = isl1208_i2c_get_sr(client); 537 if (sr < 0) { 538 dev_err(dev, "%s: reading SR failed\n", __func__); 539 return sr; 540 } 541 542 sr &= ~ISL1208_REG_SR_EVT; 543 544 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr); 545 if (sr < 0) 546 dev_err(dev, "%s: writing SR failed\n", 547 __func__); 548 549 return count; 550 }; 551 552 static ssize_t timestamp0_show(struct device *dev, 553 struct device_attribute *attr, char *buf) 554 { 555 struct i2c_client *client = to_i2c_client(dev->parent); 556 u8 regs[ISL1219_EVT_SECTION_LEN] = { 0, }; 557 struct rtc_time tm; 558 int sr; 559 560 sr = isl1208_i2c_get_sr(client); 561 if (sr < 0) { 562 dev_err(dev, "%s: reading SR failed\n", __func__); 563 return sr; 564 } 565 566 if (!(sr & ISL1208_REG_SR_EVT)) 567 return 0; 568 569 sr = isl1208_i2c_read_regs(client, ISL1219_REG_SCT, regs, 570 ISL1219_EVT_SECTION_LEN); 571 if (sr < 0) { 572 dev_err(dev, "%s: reading event section failed\n", 573 __func__); 574 return 0; 575 } 576 577 /* MSB of each alarm register is an enable bit */ 578 tm.tm_sec = bcd2bin(regs[ISL1219_REG_SCT - ISL1219_REG_SCT] & 0x7f); 579 tm.tm_min = bcd2bin(regs[ISL1219_REG_MNT - ISL1219_REG_SCT] & 0x7f); 580 tm.tm_hour = bcd2bin(regs[ISL1219_REG_HRT - ISL1219_REG_SCT] & 0x3f); 581 tm.tm_mday = bcd2bin(regs[ISL1219_REG_DTT - ISL1219_REG_SCT] & 0x3f); 582 tm.tm_mon = 583 bcd2bin(regs[ISL1219_REG_MOT - ISL1219_REG_SCT] & 0x1f) - 1; 584 tm.tm_year = bcd2bin(regs[ISL1219_REG_YRT - ISL1219_REG_SCT]) + 100; 585 586 sr = rtc_valid_tm(&tm); 587 if (sr) 588 return sr; 589 590 return sprintf(buf, "%llu\n", 591 (unsigned long long)rtc_tm_to_time64(&tm)); 592 }; 593 594 static DEVICE_ATTR_RW(timestamp0); 595 596 static irqreturn_t 597 isl1208_rtc_interrupt(int irq, void *data) 598 { 599 unsigned long timeout = jiffies + msecs_to_jiffies(1000); 600 struct i2c_client *client = data; 601 struct isl1208_state *isl1208 = i2c_get_clientdata(client); 602 int handled = 0, sr, err; 603 604 /* 605 * I2C reads get NAK'ed if we read straight away after an interrupt? 606 * Using a mdelay/msleep didn't seem to help either, so we work around 607 * this by continually trying to read the register for a short time. 608 */ 609 while (1) { 610 sr = isl1208_i2c_get_sr(client); 611 if (sr >= 0) 612 break; 613 614 if (time_after(jiffies, timeout)) { 615 dev_err(&client->dev, "%s: reading SR failed\n", 616 __func__); 617 return sr; 618 } 619 } 620 621 if (sr & ISL1208_REG_SR_ALM) { 622 dev_dbg(&client->dev, "alarm!\n"); 623 624 rtc_update_irq(isl1208->rtc, 1, RTC_IRQF | RTC_AF); 625 626 /* Clear the alarm */ 627 sr &= ~ISL1208_REG_SR_ALM; 628 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr); 629 if (sr < 0) 630 dev_err(&client->dev, "%s: writing SR failed\n", 631 __func__); 632 else 633 handled = 1; 634 635 /* Disable the alarm */ 636 err = isl1208_rtc_toggle_alarm(client, 0); 637 if (err) 638 return err; 639 } 640 641 if (isl1208->config->has_tamper && (sr & ISL1208_REG_SR_EVT)) { 642 dev_warn(&client->dev, "event detected"); 643 handled = 1; 644 if (isl1208->config->has_timestamp) 645 sysfs_notify(&isl1208->rtc->dev.kobj, NULL, 646 dev_attr_timestamp0.attr.name); 647 } 648 649 return handled ? IRQ_HANDLED : IRQ_NONE; 650 } 651 652 static const struct rtc_class_ops isl1208_rtc_ops = { 653 .proc = isl1208_rtc_proc, 654 .read_time = isl1208_rtc_read_time, 655 .set_time = isl1208_rtc_set_time, 656 .read_alarm = isl1208_rtc_read_alarm, 657 .set_alarm = isl1208_rtc_set_alarm, 658 }; 659 660 /* sysfs interface */ 661 662 static ssize_t 663 isl1208_sysfs_show_atrim(struct device *dev, 664 struct device_attribute *attr, char *buf) 665 { 666 int atr = isl1208_i2c_get_atr(to_i2c_client(dev->parent)); 667 if (atr < 0) 668 return atr; 669 670 return sprintf(buf, "%d.%.2d pF\n", atr >> 2, (atr & 0x3) * 25); 671 } 672 673 static DEVICE_ATTR(atrim, S_IRUGO, isl1208_sysfs_show_atrim, NULL); 674 675 static ssize_t 676 isl1208_sysfs_show_dtrim(struct device *dev, 677 struct device_attribute *attr, char *buf) 678 { 679 int dtr = isl1208_i2c_get_dtr(to_i2c_client(dev->parent)); 680 if (dtr < 0) 681 return dtr; 682 683 return sprintf(buf, "%d ppm\n", dtr - 100); 684 } 685 686 static DEVICE_ATTR(dtrim, S_IRUGO, isl1208_sysfs_show_dtrim, NULL); 687 688 static ssize_t 689 isl1208_sysfs_show_usr(struct device *dev, 690 struct device_attribute *attr, char *buf) 691 { 692 int usr = isl1208_i2c_get_usr(to_i2c_client(dev->parent)); 693 if (usr < 0) 694 return usr; 695 696 return sprintf(buf, "0x%.4x\n", usr); 697 } 698 699 static ssize_t 700 isl1208_sysfs_store_usr(struct device *dev, 701 struct device_attribute *attr, 702 const char *buf, size_t count) 703 { 704 int usr = -1; 705 706 if (buf[0] == '0' && (buf[1] == 'x' || buf[1] == 'X')) { 707 if (sscanf(buf, "%x", &usr) != 1) 708 return -EINVAL; 709 } else { 710 if (sscanf(buf, "%d", &usr) != 1) 711 return -EINVAL; 712 } 713 714 if (usr < 0 || usr > 0xffff) 715 return -EINVAL; 716 717 if (isl1208_i2c_set_usr(to_i2c_client(dev->parent), usr)) 718 return -EIO; 719 720 return count; 721 } 722 723 static DEVICE_ATTR(usr, S_IRUGO | S_IWUSR, isl1208_sysfs_show_usr, 724 isl1208_sysfs_store_usr); 725 726 static struct attribute *isl1208_rtc_attrs[] = { 727 &dev_attr_atrim.attr, 728 &dev_attr_dtrim.attr, 729 &dev_attr_usr.attr, 730 NULL 731 }; 732 733 static const struct attribute_group isl1208_rtc_sysfs_files = { 734 .attrs = isl1208_rtc_attrs, 735 }; 736 737 static struct attribute *isl1219_rtc_attrs[] = { 738 &dev_attr_timestamp0.attr, 739 NULL 740 }; 741 742 static const struct attribute_group isl1219_rtc_sysfs_files = { 743 .attrs = isl1219_rtc_attrs, 744 }; 745 746 static int isl1208_nvmem_read(void *priv, unsigned int off, void *buf, 747 size_t count) 748 { 749 struct isl1208_state *isl1208 = priv; 750 struct i2c_client *client = to_i2c_client(isl1208->rtc->dev.parent); 751 int ret; 752 753 /* nvmem sanitizes offset/count for us, but count==0 is possible */ 754 if (!count) 755 return count; 756 ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1 + off, buf, 757 count); 758 return ret == 0 ? count : ret; 759 } 760 761 static int isl1208_nvmem_write(void *priv, unsigned int off, void *buf, 762 size_t count) 763 { 764 struct isl1208_state *isl1208 = priv; 765 struct i2c_client *client = to_i2c_client(isl1208->rtc->dev.parent); 766 int ret; 767 768 /* nvmem sanitizes off/count for us, but count==0 is possible */ 769 if (!count) 770 return count; 771 ret = isl1208_i2c_set_regs(client, ISL1208_REG_USR1 + off, buf, 772 count); 773 774 return ret == 0 ? count : ret; 775 } 776 777 static const struct nvmem_config isl1208_nvmem_config = { 778 .name = "isl1208_nvram", 779 .word_size = 1, 780 .stride = 1, 781 /* .size from chip specific config */ 782 .reg_read = isl1208_nvmem_read, 783 .reg_write = isl1208_nvmem_write, 784 }; 785 786 static int isl1208_setup_irq(struct i2c_client *client, int irq) 787 { 788 int rc = devm_request_threaded_irq(&client->dev, irq, NULL, 789 isl1208_rtc_interrupt, 790 IRQF_SHARED | IRQF_ONESHOT, 791 isl1208_driver.driver.name, 792 client); 793 if (!rc) { 794 device_init_wakeup(&client->dev, 1); 795 enable_irq_wake(irq); 796 } else { 797 dev_err(&client->dev, 798 "Unable to request irq %d, no alarm support\n", 799 irq); 800 } 801 return rc; 802 } 803 804 static int 805 isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id) 806 { 807 int rc = 0; 808 struct isl1208_state *isl1208; 809 int evdet_irq = -1; 810 811 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) 812 return -ENODEV; 813 814 if (isl1208_i2c_validate_client(client) < 0) 815 return -ENODEV; 816 817 /* Allocate driver state, point i2c client data to it */ 818 isl1208 = devm_kzalloc(&client->dev, sizeof(*isl1208), GFP_KERNEL); 819 if (!isl1208) 820 return -ENOMEM; 821 i2c_set_clientdata(client, isl1208); 822 823 /* Determine which chip we have */ 824 if (client->dev.of_node) { 825 isl1208->config = of_device_get_match_data(&client->dev); 826 if (!isl1208->config) 827 return -ENODEV; 828 } else { 829 if (id->driver_data >= ISL_LAST_ID) 830 return -ENODEV; 831 isl1208->config = &isl1208_configs[id->driver_data]; 832 } 833 834 isl1208->rtc = devm_rtc_allocate_device(&client->dev); 835 if (IS_ERR(isl1208->rtc)) 836 return PTR_ERR(isl1208->rtc); 837 838 isl1208->rtc->ops = &isl1208_rtc_ops; 839 840 /* Setup nvmem configuration in driver state struct */ 841 isl1208->nvmem_config = isl1208_nvmem_config; 842 isl1208->nvmem_config.size = isl1208->config->nvmem_length; 843 isl1208->nvmem_config.priv = isl1208; 844 845 rc = isl1208_i2c_get_sr(client); 846 if (rc < 0) { 847 dev_err(&client->dev, "reading status failed\n"); 848 return rc; 849 } 850 851 if (rc & ISL1208_REG_SR_RTCF) 852 dev_warn(&client->dev, "rtc power failure detected, " 853 "please set clock.\n"); 854 855 if (isl1208->config->has_tamper) { 856 struct device_node *np = client->dev.of_node; 857 u32 evienb; 858 859 rc = i2c_smbus_read_byte_data(client, ISL1219_REG_EV); 860 if (rc < 0) { 861 dev_err(&client->dev, "failed to read EV reg\n"); 862 return rc; 863 } 864 rc |= ISL1219_REG_EV_EVEN; 865 if (!of_property_read_u32(np, "isil,ev-evienb", &evienb)) { 866 if (evienb) 867 rc |= ISL1219_REG_EV_EVIENB; 868 else 869 rc &= ~ISL1219_REG_EV_EVIENB; 870 } 871 rc = i2c_smbus_write_byte_data(client, ISL1219_REG_EV, rc); 872 if (rc < 0) { 873 dev_err(&client->dev, "could not enable tamper detection\n"); 874 return rc; 875 } 876 evdet_irq = of_irq_get_byname(np, "evdet"); 877 } 878 if (isl1208->config->has_timestamp) { 879 rc = rtc_add_group(isl1208->rtc, &isl1219_rtc_sysfs_files); 880 if (rc) 881 return rc; 882 } 883 884 rc = rtc_add_group(isl1208->rtc, &isl1208_rtc_sysfs_files); 885 if (rc) 886 return rc; 887 888 if (client->irq > 0) 889 rc = isl1208_setup_irq(client, client->irq); 890 if (rc) 891 return rc; 892 893 if (evdet_irq > 0 && evdet_irq != client->irq) 894 rc = isl1208_setup_irq(client, evdet_irq); 895 if (rc) 896 return rc; 897 898 rc = rtc_nvmem_register(isl1208->rtc, &isl1208->nvmem_config); 899 if (rc) 900 return rc; 901 902 return rtc_register_device(isl1208->rtc); 903 } 904 905 static struct i2c_driver isl1208_driver = { 906 .driver = { 907 .name = "rtc-isl1208", 908 .of_match_table = of_match_ptr(isl1208_of_match), 909 }, 910 .probe = isl1208_probe, 911 .id_table = isl1208_id, 912 }; 913 914 module_i2c_driver(isl1208_driver); 915 916 MODULE_AUTHOR("Herbert Valerio Riedel <hvr@gnu.org>"); 917 MODULE_DESCRIPTION("Intersil ISL1208 RTC driver"); 918 MODULE_LICENSE("GPL"); 919