1 /* 2 * Driver for the Epson RTC module RX-8010 SJ 3 * 4 * Copyright(C) Timesys Corporation 2015 5 * Copyright(C) General Electric Company 2015 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 */ 12 13 #include <linux/bcd.h> 14 #include <linux/bitops.h> 15 #include <linux/i2c.h> 16 #include <linux/kernel.h> 17 #include <linux/module.h> 18 #include <linux/rtc.h> 19 20 #define RX8010_SEC 0x10 21 #define RX8010_MIN 0x11 22 #define RX8010_HOUR 0x12 23 #define RX8010_WDAY 0x13 24 #define RX8010_MDAY 0x14 25 #define RX8010_MONTH 0x15 26 #define RX8010_YEAR 0x16 27 #define RX8010_RESV17 0x17 28 #define RX8010_ALMIN 0x18 29 #define RX8010_ALHOUR 0x19 30 #define RX8010_ALWDAY 0x1A 31 #define RX8010_TCOUNT0 0x1B 32 #define RX8010_TCOUNT1 0x1C 33 #define RX8010_EXT 0x1D 34 #define RX8010_FLAG 0x1E 35 #define RX8010_CTRL 0x1F 36 /* 0x20 to 0x2F are user registers */ 37 #define RX8010_RESV30 0x30 38 #define RX8010_RESV31 0x31 39 #define RX8010_IRQ 0x32 40 41 #define RX8010_EXT_WADA BIT(3) 42 43 #define RX8010_FLAG_VLF BIT(1) 44 #define RX8010_FLAG_AF BIT(3) 45 #define RX8010_FLAG_TF BIT(4) 46 #define RX8010_FLAG_UF BIT(5) 47 48 #define RX8010_CTRL_AIE BIT(3) 49 #define RX8010_CTRL_UIE BIT(5) 50 #define RX8010_CTRL_STOP BIT(6) 51 #define RX8010_CTRL_TEST BIT(7) 52 53 #define RX8010_ALARM_AE BIT(7) 54 55 static const struct i2c_device_id rx8010_id[] = { 56 { "rx8010", 0 }, 57 { } 58 }; 59 MODULE_DEVICE_TABLE(i2c, rx8010_id); 60 61 static const struct of_device_id rx8010_of_match[] = { 62 { .compatible = "epson,rx8010" }, 63 { } 64 }; 65 MODULE_DEVICE_TABLE(of, rx8010_of_match); 66 67 struct rx8010_data { 68 struct i2c_client *client; 69 struct rtc_device *rtc; 70 u8 ctrlreg; 71 }; 72 73 static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id) 74 { 75 struct i2c_client *client = dev_id; 76 struct rx8010_data *rx8010 = i2c_get_clientdata(client); 77 int flagreg; 78 79 mutex_lock(&rx8010->rtc->ops_lock); 80 81 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); 82 83 if (flagreg <= 0) { 84 mutex_unlock(&rx8010->rtc->ops_lock); 85 return IRQ_NONE; 86 } 87 88 if (flagreg & RX8010_FLAG_VLF) 89 dev_warn(&client->dev, "Frequency stop detected\n"); 90 91 if (flagreg & RX8010_FLAG_TF) { 92 flagreg &= ~RX8010_FLAG_TF; 93 rtc_update_irq(rx8010->rtc, 1, RTC_PF | RTC_IRQF); 94 } 95 96 if (flagreg & RX8010_FLAG_AF) { 97 flagreg &= ~RX8010_FLAG_AF; 98 rtc_update_irq(rx8010->rtc, 1, RTC_AF | RTC_IRQF); 99 } 100 101 if (flagreg & RX8010_FLAG_UF) { 102 flagreg &= ~RX8010_FLAG_UF; 103 rtc_update_irq(rx8010->rtc, 1, RTC_UF | RTC_IRQF); 104 } 105 106 i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg); 107 108 mutex_unlock(&rx8010->rtc->ops_lock); 109 return IRQ_HANDLED; 110 } 111 112 static int rx8010_get_time(struct device *dev, struct rtc_time *dt) 113 { 114 struct rx8010_data *rx8010 = dev_get_drvdata(dev); 115 u8 date[7]; 116 int flagreg; 117 int err; 118 119 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); 120 if (flagreg < 0) 121 return flagreg; 122 123 if (flagreg & RX8010_FLAG_VLF) { 124 dev_warn(dev, "Frequency stop detected\n"); 125 return -EINVAL; 126 } 127 128 err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_SEC, 129 7, date); 130 if (err != 7) 131 return err < 0 ? err : -EIO; 132 133 dt->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f); 134 dt->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f); 135 dt->tm_hour = bcd2bin(date[RX8010_HOUR - RX8010_SEC] & 0x3f); 136 dt->tm_mday = bcd2bin(date[RX8010_MDAY - RX8010_SEC] & 0x3f); 137 dt->tm_mon = bcd2bin(date[RX8010_MONTH - RX8010_SEC] & 0x1f) - 1; 138 dt->tm_year = bcd2bin(date[RX8010_YEAR - RX8010_SEC]) + 100; 139 dt->tm_wday = ffs(date[RX8010_WDAY - RX8010_SEC] & 0x7f); 140 141 return 0; 142 } 143 144 static int rx8010_set_time(struct device *dev, struct rtc_time *dt) 145 { 146 struct rx8010_data *rx8010 = dev_get_drvdata(dev); 147 u8 date[7]; 148 int ctrl, flagreg; 149 int ret; 150 151 if ((dt->tm_year < 100) || (dt->tm_year > 199)) 152 return -EINVAL; 153 154 /* set STOP bit before changing clock/calendar */ 155 ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL); 156 if (ctrl < 0) 157 return ctrl; 158 rx8010->ctrlreg = ctrl | RX8010_CTRL_STOP; 159 ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, 160 rx8010->ctrlreg); 161 if (ret < 0) 162 return ret; 163 164 date[RX8010_SEC - RX8010_SEC] = bin2bcd(dt->tm_sec); 165 date[RX8010_MIN - RX8010_SEC] = bin2bcd(dt->tm_min); 166 date[RX8010_HOUR - RX8010_SEC] = bin2bcd(dt->tm_hour); 167 date[RX8010_MDAY - RX8010_SEC] = bin2bcd(dt->tm_mday); 168 date[RX8010_MONTH - RX8010_SEC] = bin2bcd(dt->tm_mon + 1); 169 date[RX8010_YEAR - RX8010_SEC] = bin2bcd(dt->tm_year - 100); 170 date[RX8010_WDAY - RX8010_SEC] = bin2bcd(1 << dt->tm_wday); 171 172 ret = i2c_smbus_write_i2c_block_data(rx8010->client, 173 RX8010_SEC, 7, date); 174 if (ret < 0) 175 return ret; 176 177 /* clear STOP bit after changing clock/calendar */ 178 ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL); 179 if (ctrl < 0) 180 return ctrl; 181 rx8010->ctrlreg = ctrl & ~RX8010_CTRL_STOP; 182 ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, 183 rx8010->ctrlreg); 184 if (ret < 0) 185 return ret; 186 187 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); 188 if (flagreg < 0) { 189 return flagreg; 190 } 191 192 if (flagreg & RX8010_FLAG_VLF) 193 ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, 194 flagreg & ~RX8010_FLAG_VLF); 195 196 return 0; 197 } 198 199 static int rx8010_init_client(struct i2c_client *client) 200 { 201 struct rx8010_data *rx8010 = i2c_get_clientdata(client); 202 u8 ctrl[2]; 203 int need_clear = 0, err = 0; 204 205 /* Initialize reserved registers as specified in datasheet */ 206 err = i2c_smbus_write_byte_data(client, RX8010_RESV17, 0xD8); 207 if (err < 0) 208 return err; 209 210 err = i2c_smbus_write_byte_data(client, RX8010_RESV30, 0x00); 211 if (err < 0) 212 return err; 213 214 err = i2c_smbus_write_byte_data(client, RX8010_RESV31, 0x08); 215 if (err < 0) 216 return err; 217 218 err = i2c_smbus_write_byte_data(client, RX8010_IRQ, 0x00); 219 if (err < 0) 220 return err; 221 222 err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_FLAG, 223 2, ctrl); 224 if (err != 2) 225 return err < 0 ? err : -EIO; 226 227 if (ctrl[0] & RX8010_FLAG_VLF) 228 dev_warn(&client->dev, "Frequency stop was detected\n"); 229 230 if (ctrl[0] & RX8010_FLAG_AF) { 231 dev_warn(&client->dev, "Alarm was detected\n"); 232 need_clear = 1; 233 } 234 235 if (ctrl[0] & RX8010_FLAG_TF) 236 need_clear = 1; 237 238 if (ctrl[0] & RX8010_FLAG_UF) 239 need_clear = 1; 240 241 if (need_clear) { 242 ctrl[0] &= ~(RX8010_FLAG_AF | RX8010_FLAG_TF | RX8010_FLAG_UF); 243 err = i2c_smbus_write_byte_data(client, RX8010_FLAG, ctrl[0]); 244 if (err < 0) 245 return err; 246 } 247 248 rx8010->ctrlreg = (ctrl[1] & ~RX8010_CTRL_TEST); 249 250 return 0; 251 } 252 253 static int rx8010_read_alarm(struct device *dev, struct rtc_wkalrm *t) 254 { 255 struct rx8010_data *rx8010 = dev_get_drvdata(dev); 256 struct i2c_client *client = rx8010->client; 257 u8 alarmvals[3]; 258 int flagreg; 259 int err; 260 261 err = i2c_smbus_read_i2c_block_data(client, RX8010_ALMIN, 3, alarmvals); 262 if (err != 3) 263 return err < 0 ? err : -EIO; 264 265 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); 266 if (flagreg < 0) 267 return flagreg; 268 269 t->time.tm_sec = 0; 270 t->time.tm_min = bcd2bin(alarmvals[0] & 0x7f); 271 t->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f); 272 273 if (!(alarmvals[2] & RX8010_ALARM_AE)) 274 t->time.tm_mday = bcd2bin(alarmvals[2] & 0x7f); 275 276 t->enabled = !!(rx8010->ctrlreg & RX8010_CTRL_AIE); 277 t->pending = (flagreg & RX8010_FLAG_AF) && t->enabled; 278 279 return 0; 280 } 281 282 static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t) 283 { 284 struct i2c_client *client = to_i2c_client(dev); 285 struct rx8010_data *rx8010 = dev_get_drvdata(dev); 286 u8 alarmvals[3]; 287 int extreg, flagreg; 288 int err; 289 290 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); 291 if (flagreg < 0) { 292 return flagreg; 293 } 294 295 if (rx8010->ctrlreg & (RX8010_CTRL_AIE | RX8010_CTRL_UIE)) { 296 rx8010->ctrlreg &= ~(RX8010_CTRL_AIE | RX8010_CTRL_UIE); 297 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, 298 rx8010->ctrlreg); 299 if (err < 0) { 300 return err; 301 } 302 } 303 304 flagreg &= ~RX8010_FLAG_AF; 305 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg); 306 if (err < 0) 307 return err; 308 309 alarmvals[0] = bin2bcd(t->time.tm_min); 310 alarmvals[1] = bin2bcd(t->time.tm_hour); 311 alarmvals[2] = bin2bcd(t->time.tm_mday); 312 313 err = i2c_smbus_write_i2c_block_data(rx8010->client, RX8010_ALMIN, 314 2, alarmvals); 315 if (err < 0) 316 return err; 317 318 extreg = i2c_smbus_read_byte_data(client, RX8010_EXT); 319 if (extreg < 0) 320 return extreg; 321 322 extreg |= RX8010_EXT_WADA; 323 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_EXT, extreg); 324 if (err < 0) 325 return err; 326 327 if (alarmvals[2] == 0) 328 alarmvals[2] |= RX8010_ALARM_AE; 329 330 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_ALWDAY, 331 alarmvals[2]); 332 if (err < 0) 333 return err; 334 335 if (t->enabled) { 336 if (rx8010->rtc->uie_rtctimer.enabled) 337 rx8010->ctrlreg |= RX8010_CTRL_UIE; 338 if (rx8010->rtc->aie_timer.enabled) 339 rx8010->ctrlreg |= 340 (RX8010_CTRL_AIE | RX8010_CTRL_UIE); 341 342 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, 343 rx8010->ctrlreg); 344 if (err < 0) 345 return err; 346 } 347 348 return 0; 349 } 350 351 static int rx8010_alarm_irq_enable(struct device *dev, 352 unsigned int enabled) 353 { 354 struct i2c_client *client = to_i2c_client(dev); 355 struct rx8010_data *rx8010 = dev_get_drvdata(dev); 356 int flagreg; 357 u8 ctrl; 358 int err; 359 360 ctrl = rx8010->ctrlreg; 361 362 if (enabled) { 363 if (rx8010->rtc->uie_rtctimer.enabled) 364 ctrl |= RX8010_CTRL_UIE; 365 if (rx8010->rtc->aie_timer.enabled) 366 ctrl |= (RX8010_CTRL_AIE | RX8010_CTRL_UIE); 367 } else { 368 if (!rx8010->rtc->uie_rtctimer.enabled) 369 ctrl &= ~RX8010_CTRL_UIE; 370 if (!rx8010->rtc->aie_timer.enabled) 371 ctrl &= ~RX8010_CTRL_AIE; 372 } 373 374 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); 375 if (flagreg < 0) 376 return flagreg; 377 378 flagreg &= ~RX8010_FLAG_AF; 379 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg); 380 if (err < 0) 381 return err; 382 383 if (ctrl != rx8010->ctrlreg) { 384 rx8010->ctrlreg = ctrl; 385 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, 386 rx8010->ctrlreg); 387 if (err < 0) 388 return err; 389 } 390 391 return 0; 392 } 393 394 static int rx8010_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) 395 { 396 struct i2c_client *client = to_i2c_client(dev); 397 struct rx8010_data *rx8010 = dev_get_drvdata(dev); 398 int ret, tmp; 399 int flagreg; 400 401 switch (cmd) { 402 case RTC_VL_READ: 403 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); 404 if (flagreg < 0) 405 return flagreg; 406 407 tmp = !!(flagreg & RX8010_FLAG_VLF); 408 if (copy_to_user((void __user *)arg, &tmp, sizeof(int))) 409 return -EFAULT; 410 411 return 0; 412 413 case RTC_VL_CLR: 414 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); 415 if (flagreg < 0) { 416 return flagreg; 417 } 418 419 flagreg &= ~RX8010_FLAG_VLF; 420 ret = i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg); 421 if (ret < 0) 422 return ret; 423 424 return 0; 425 426 default: 427 return -ENOIOCTLCMD; 428 } 429 } 430 431 static struct rtc_class_ops rx8010_rtc_ops = { 432 .read_time = rx8010_get_time, 433 .set_time = rx8010_set_time, 434 .ioctl = rx8010_ioctl, 435 }; 436 437 static int rx8010_probe(struct i2c_client *client, 438 const struct i2c_device_id *id) 439 { 440 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); 441 struct rx8010_data *rx8010; 442 int err = 0; 443 444 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA 445 | I2C_FUNC_SMBUS_I2C_BLOCK)) { 446 dev_err(&adapter->dev, "doesn't support required functionality\n"); 447 return -EIO; 448 } 449 450 rx8010 = devm_kzalloc(&client->dev, sizeof(struct rx8010_data), 451 GFP_KERNEL); 452 if (!rx8010) 453 return -ENOMEM; 454 455 rx8010->client = client; 456 i2c_set_clientdata(client, rx8010); 457 458 err = rx8010_init_client(client); 459 if (err) 460 return err; 461 462 if (client->irq > 0) { 463 dev_info(&client->dev, "IRQ %d supplied\n", client->irq); 464 err = devm_request_threaded_irq(&client->dev, client->irq, NULL, 465 rx8010_irq_1_handler, 466 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 467 "rx8010", client); 468 469 if (err) { 470 dev_err(&client->dev, "unable to request IRQ\n"); 471 client->irq = 0; 472 } else { 473 rx8010_rtc_ops.read_alarm = rx8010_read_alarm; 474 rx8010_rtc_ops.set_alarm = rx8010_set_alarm; 475 rx8010_rtc_ops.alarm_irq_enable = rx8010_alarm_irq_enable; 476 } 477 } 478 479 rx8010->rtc = devm_rtc_device_register(&client->dev, client->name, 480 &rx8010_rtc_ops, THIS_MODULE); 481 482 if (IS_ERR(rx8010->rtc)) { 483 dev_err(&client->dev, "unable to register the class device\n"); 484 return PTR_ERR(rx8010->rtc); 485 } 486 487 rx8010->rtc->max_user_freq = 1; 488 489 return err; 490 } 491 492 static struct i2c_driver rx8010_driver = { 493 .driver = { 494 .name = "rtc-rx8010", 495 .of_match_table = of_match_ptr(rx8010_of_match), 496 }, 497 .probe = rx8010_probe, 498 .id_table = rx8010_id, 499 }; 500 501 module_i2c_driver(rx8010_driver); 502 503 MODULE_AUTHOR("Akshay Bhat <akshay.bhat@timesys.com>"); 504 MODULE_DESCRIPTION("Epson RX8010SJ RTC driver"); 505 MODULE_LICENSE("GPL v2"); 506