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