1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Haoyu HYM8563 RTC driver 4 * 5 * Copyright (C) 2013 MundoReader S.L. 6 * Author: Heiko Stuebner <heiko@sntech.de> 7 * 8 * based on rtc-HYM8563 9 * Copyright (C) 2010 ROCKCHIP, Inc. 10 */ 11 12 #include <linux/module.h> 13 #include <linux/clk-provider.h> 14 #include <linux/i2c.h> 15 #include <linux/bcd.h> 16 #include <linux/rtc.h> 17 18 #define HYM8563_CTL1 0x00 19 #define HYM8563_CTL1_TEST BIT(7) 20 #define HYM8563_CTL1_STOP BIT(5) 21 #define HYM8563_CTL1_TESTC BIT(3) 22 23 #define HYM8563_CTL2 0x01 24 #define HYM8563_CTL2_TI_TP BIT(4) 25 #define HYM8563_CTL2_AF BIT(3) 26 #define HYM8563_CTL2_TF BIT(2) 27 #define HYM8563_CTL2_AIE BIT(1) 28 #define HYM8563_CTL2_TIE BIT(0) 29 30 #define HYM8563_SEC 0x02 31 #define HYM8563_SEC_VL BIT(7) 32 #define HYM8563_SEC_MASK 0x7f 33 34 #define HYM8563_MIN 0x03 35 #define HYM8563_MIN_MASK 0x7f 36 37 #define HYM8563_HOUR 0x04 38 #define HYM8563_HOUR_MASK 0x3f 39 40 #define HYM8563_DAY 0x05 41 #define HYM8563_DAY_MASK 0x3f 42 43 #define HYM8563_WEEKDAY 0x06 44 #define HYM8563_WEEKDAY_MASK 0x07 45 46 #define HYM8563_MONTH 0x07 47 #define HYM8563_MONTH_CENTURY BIT(7) 48 #define HYM8563_MONTH_MASK 0x1f 49 50 #define HYM8563_YEAR 0x08 51 52 #define HYM8563_ALM_MIN 0x09 53 #define HYM8563_ALM_HOUR 0x0a 54 #define HYM8563_ALM_DAY 0x0b 55 #define HYM8563_ALM_WEEK 0x0c 56 57 /* Each alarm check can be disabled by setting this bit in the register */ 58 #define HYM8563_ALM_BIT_DISABLE BIT(7) 59 60 #define HYM8563_CLKOUT 0x0d 61 #define HYM8563_CLKOUT_ENABLE BIT(7) 62 #define HYM8563_CLKOUT_32768 0 63 #define HYM8563_CLKOUT_1024 1 64 #define HYM8563_CLKOUT_32 2 65 #define HYM8563_CLKOUT_1 3 66 #define HYM8563_CLKOUT_MASK 3 67 68 #define HYM8563_TMR_CTL 0x0e 69 #define HYM8563_TMR_CTL_ENABLE BIT(7) 70 #define HYM8563_TMR_CTL_4096 0 71 #define HYM8563_TMR_CTL_64 1 72 #define HYM8563_TMR_CTL_1 2 73 #define HYM8563_TMR_CTL_1_60 3 74 #define HYM8563_TMR_CTL_MASK 3 75 76 #define HYM8563_TMR_CNT 0x0f 77 78 struct hym8563 { 79 struct i2c_client *client; 80 struct rtc_device *rtc; 81 bool valid; 82 #ifdef CONFIG_COMMON_CLK 83 struct clk_hw clkout_hw; 84 #endif 85 }; 86 87 /* 88 * RTC handling 89 */ 90 91 static int hym8563_rtc_read_time(struct device *dev, struct rtc_time *tm) 92 { 93 struct i2c_client *client = to_i2c_client(dev); 94 struct hym8563 *hym8563 = i2c_get_clientdata(client); 95 u8 buf[7]; 96 int ret; 97 98 if (!hym8563->valid) { 99 dev_warn(&client->dev, "no valid clock/calendar values available\n"); 100 return -EPERM; 101 } 102 103 ret = i2c_smbus_read_i2c_block_data(client, HYM8563_SEC, 7, buf); 104 if (ret < 0) 105 return ret; 106 107 tm->tm_sec = bcd2bin(buf[0] & HYM8563_SEC_MASK); 108 tm->tm_min = bcd2bin(buf[1] & HYM8563_MIN_MASK); 109 tm->tm_hour = bcd2bin(buf[2] & HYM8563_HOUR_MASK); 110 tm->tm_mday = bcd2bin(buf[3] & HYM8563_DAY_MASK); 111 tm->tm_wday = bcd2bin(buf[4] & HYM8563_WEEKDAY_MASK); /* 0 = Sun */ 112 tm->tm_mon = bcd2bin(buf[5] & HYM8563_MONTH_MASK) - 1; /* 0 = Jan */ 113 tm->tm_year = bcd2bin(buf[6]) + 100; 114 115 return 0; 116 } 117 118 static int hym8563_rtc_set_time(struct device *dev, struct rtc_time *tm) 119 { 120 struct i2c_client *client = to_i2c_client(dev); 121 struct hym8563 *hym8563 = i2c_get_clientdata(client); 122 u8 buf[7]; 123 int ret; 124 125 /* Years >= 2100 are to far in the future, 19XX is to early */ 126 if (tm->tm_year < 100 || tm->tm_year >= 200) 127 return -EINVAL; 128 129 buf[0] = bin2bcd(tm->tm_sec); 130 buf[1] = bin2bcd(tm->tm_min); 131 buf[2] = bin2bcd(tm->tm_hour); 132 buf[3] = bin2bcd(tm->tm_mday); 133 buf[4] = bin2bcd(tm->tm_wday); 134 buf[5] = bin2bcd(tm->tm_mon + 1); 135 136 /* 137 * While the HYM8563 has a century flag in the month register, 138 * it does not seem to carry it over a subsequent write/read. 139 * So we'll limit ourself to 100 years, starting at 2000 for now. 140 */ 141 buf[6] = bin2bcd(tm->tm_year - 100); 142 143 /* 144 * CTL1 only contains TEST-mode bits apart from stop, 145 * so no need to read the value first 146 */ 147 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 148 HYM8563_CTL1_STOP); 149 if (ret < 0) 150 return ret; 151 152 ret = i2c_smbus_write_i2c_block_data(client, HYM8563_SEC, 7, buf); 153 if (ret < 0) 154 return ret; 155 156 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0); 157 if (ret < 0) 158 return ret; 159 160 hym8563->valid = true; 161 162 return 0; 163 } 164 165 static int hym8563_rtc_alarm_irq_enable(struct device *dev, 166 unsigned int enabled) 167 { 168 struct i2c_client *client = to_i2c_client(dev); 169 int data; 170 171 data = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 172 if (data < 0) 173 return data; 174 175 if (enabled) 176 data |= HYM8563_CTL2_AIE; 177 else 178 data &= ~HYM8563_CTL2_AIE; 179 180 return i2c_smbus_write_byte_data(client, HYM8563_CTL2, data); 181 }; 182 183 static int hym8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) 184 { 185 struct i2c_client *client = to_i2c_client(dev); 186 struct rtc_time *alm_tm = &alm->time; 187 u8 buf[4]; 188 int ret; 189 190 ret = i2c_smbus_read_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf); 191 if (ret < 0) 192 return ret; 193 194 /* The alarm only has a minute accuracy */ 195 alm_tm->tm_sec = 0; 196 197 alm_tm->tm_min = (buf[0] & HYM8563_ALM_BIT_DISABLE) ? 198 -1 : 199 bcd2bin(buf[0] & HYM8563_MIN_MASK); 200 alm_tm->tm_hour = (buf[1] & HYM8563_ALM_BIT_DISABLE) ? 201 -1 : 202 bcd2bin(buf[1] & HYM8563_HOUR_MASK); 203 alm_tm->tm_mday = (buf[2] & HYM8563_ALM_BIT_DISABLE) ? 204 -1 : 205 bcd2bin(buf[2] & HYM8563_DAY_MASK); 206 alm_tm->tm_wday = (buf[3] & HYM8563_ALM_BIT_DISABLE) ? 207 -1 : 208 bcd2bin(buf[3] & HYM8563_WEEKDAY_MASK); 209 210 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 211 if (ret < 0) 212 return ret; 213 214 if (ret & HYM8563_CTL2_AIE) 215 alm->enabled = 1; 216 217 return 0; 218 } 219 220 static int hym8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) 221 { 222 struct i2c_client *client = to_i2c_client(dev); 223 struct rtc_time *alm_tm = &alm->time; 224 u8 buf[4]; 225 int ret; 226 227 /* 228 * The alarm has no seconds so deal with it 229 */ 230 if (alm_tm->tm_sec) { 231 alm_tm->tm_sec = 0; 232 alm_tm->tm_min++; 233 if (alm_tm->tm_min >= 60) { 234 alm_tm->tm_min = 0; 235 alm_tm->tm_hour++; 236 if (alm_tm->tm_hour >= 24) { 237 alm_tm->tm_hour = 0; 238 alm_tm->tm_mday++; 239 if (alm_tm->tm_mday > 31) 240 alm_tm->tm_mday = 0; 241 } 242 } 243 } 244 245 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 246 if (ret < 0) 247 return ret; 248 249 ret &= ~HYM8563_CTL2_AIE; 250 251 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret); 252 if (ret < 0) 253 return ret; 254 255 buf[0] = (alm_tm->tm_min < 60 && alm_tm->tm_min >= 0) ? 256 bin2bcd(alm_tm->tm_min) : HYM8563_ALM_BIT_DISABLE; 257 258 buf[1] = (alm_tm->tm_hour < 24 && alm_tm->tm_hour >= 0) ? 259 bin2bcd(alm_tm->tm_hour) : HYM8563_ALM_BIT_DISABLE; 260 261 buf[2] = (alm_tm->tm_mday <= 31 && alm_tm->tm_mday >= 1) ? 262 bin2bcd(alm_tm->tm_mday) : HYM8563_ALM_BIT_DISABLE; 263 264 buf[3] = (alm_tm->tm_wday < 7 && alm_tm->tm_wday >= 0) ? 265 bin2bcd(alm_tm->tm_wday) : HYM8563_ALM_BIT_DISABLE; 266 267 ret = i2c_smbus_write_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf); 268 if (ret < 0) 269 return ret; 270 271 return hym8563_rtc_alarm_irq_enable(dev, alm->enabled); 272 } 273 274 static const struct rtc_class_ops hym8563_rtc_ops = { 275 .read_time = hym8563_rtc_read_time, 276 .set_time = hym8563_rtc_set_time, 277 .alarm_irq_enable = hym8563_rtc_alarm_irq_enable, 278 .read_alarm = hym8563_rtc_read_alarm, 279 .set_alarm = hym8563_rtc_set_alarm, 280 }; 281 282 /* 283 * Handling of the clkout 284 */ 285 286 #ifdef CONFIG_COMMON_CLK 287 #define clkout_hw_to_hym8563(_hw) container_of(_hw, struct hym8563, clkout_hw) 288 289 static int clkout_rates[] = { 290 32768, 291 1024, 292 32, 293 1, 294 }; 295 296 static unsigned long hym8563_clkout_recalc_rate(struct clk_hw *hw, 297 unsigned long parent_rate) 298 { 299 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 300 struct i2c_client *client = hym8563->client; 301 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 302 303 if (ret < 0) 304 return 0; 305 306 ret &= HYM8563_CLKOUT_MASK; 307 return clkout_rates[ret]; 308 } 309 310 static long hym8563_clkout_round_rate(struct clk_hw *hw, unsigned long rate, 311 unsigned long *prate) 312 { 313 int i; 314 315 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 316 if (clkout_rates[i] <= rate) 317 return clkout_rates[i]; 318 319 return 0; 320 } 321 322 static int hym8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate, 323 unsigned long parent_rate) 324 { 325 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 326 struct i2c_client *client = hym8563->client; 327 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 328 int i; 329 330 if (ret < 0) 331 return ret; 332 333 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 334 if (clkout_rates[i] == rate) { 335 ret &= ~HYM8563_CLKOUT_MASK; 336 ret |= i; 337 return i2c_smbus_write_byte_data(client, 338 HYM8563_CLKOUT, ret); 339 } 340 341 return -EINVAL; 342 } 343 344 static int hym8563_clkout_control(struct clk_hw *hw, bool enable) 345 { 346 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 347 struct i2c_client *client = hym8563->client; 348 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 349 350 if (ret < 0) 351 return ret; 352 353 if (enable) 354 ret |= HYM8563_CLKOUT_ENABLE; 355 else 356 ret &= ~HYM8563_CLKOUT_ENABLE; 357 358 return i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, ret); 359 } 360 361 static int hym8563_clkout_prepare(struct clk_hw *hw) 362 { 363 return hym8563_clkout_control(hw, 1); 364 } 365 366 static void hym8563_clkout_unprepare(struct clk_hw *hw) 367 { 368 hym8563_clkout_control(hw, 0); 369 } 370 371 static int hym8563_clkout_is_prepared(struct clk_hw *hw) 372 { 373 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 374 struct i2c_client *client = hym8563->client; 375 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 376 377 if (ret < 0) 378 return ret; 379 380 return !!(ret & HYM8563_CLKOUT_ENABLE); 381 } 382 383 static const struct clk_ops hym8563_clkout_ops = { 384 .prepare = hym8563_clkout_prepare, 385 .unprepare = hym8563_clkout_unprepare, 386 .is_prepared = hym8563_clkout_is_prepared, 387 .recalc_rate = hym8563_clkout_recalc_rate, 388 .round_rate = hym8563_clkout_round_rate, 389 .set_rate = hym8563_clkout_set_rate, 390 }; 391 392 static struct clk *hym8563_clkout_register_clk(struct hym8563 *hym8563) 393 { 394 struct i2c_client *client = hym8563->client; 395 struct device_node *node = client->dev.of_node; 396 struct clk *clk; 397 struct clk_init_data init; 398 int ret; 399 400 ret = i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, 401 0); 402 if (ret < 0) 403 return ERR_PTR(ret); 404 405 init.name = "hym8563-clkout"; 406 init.ops = &hym8563_clkout_ops; 407 init.flags = 0; 408 init.parent_names = NULL; 409 init.num_parents = 0; 410 hym8563->clkout_hw.init = &init; 411 412 /* optional override of the clockname */ 413 of_property_read_string(node, "clock-output-names", &init.name); 414 415 /* register the clock */ 416 clk = clk_register(&client->dev, &hym8563->clkout_hw); 417 418 if (!IS_ERR(clk)) 419 of_clk_add_provider(node, of_clk_src_simple_get, clk); 420 421 return clk; 422 } 423 #endif 424 425 /* 426 * The alarm interrupt is implemented as a level-low interrupt in the 427 * hym8563, while the timer interrupt uses a falling edge. 428 * We don't use the timer at all, so the interrupt is requested to 429 * use the level-low trigger. 430 */ 431 static irqreturn_t hym8563_irq(int irq, void *dev_id) 432 { 433 struct hym8563 *hym8563 = (struct hym8563 *)dev_id; 434 struct i2c_client *client = hym8563->client; 435 struct mutex *lock = &hym8563->rtc->ops_lock; 436 int data, ret; 437 438 mutex_lock(lock); 439 440 /* Clear the alarm flag */ 441 442 data = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 443 if (data < 0) { 444 dev_err(&client->dev, "%s: error reading i2c data %d\n", 445 __func__, data); 446 goto out; 447 } 448 449 data &= ~HYM8563_CTL2_AF; 450 451 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, data); 452 if (ret < 0) { 453 dev_err(&client->dev, "%s: error writing i2c data %d\n", 454 __func__, ret); 455 } 456 457 out: 458 mutex_unlock(lock); 459 return IRQ_HANDLED; 460 } 461 462 static int hym8563_init_device(struct i2c_client *client) 463 { 464 int ret; 465 466 /* Clear stop flag if present */ 467 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0); 468 if (ret < 0) 469 return ret; 470 471 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 472 if (ret < 0) 473 return ret; 474 475 /* Disable alarm and timer interrupts */ 476 ret &= ~HYM8563_CTL2_AIE; 477 ret &= ~HYM8563_CTL2_TIE; 478 479 /* Clear any pending alarm and timer flags */ 480 if (ret & HYM8563_CTL2_AF) 481 ret &= ~HYM8563_CTL2_AF; 482 483 if (ret & HYM8563_CTL2_TF) 484 ret &= ~HYM8563_CTL2_TF; 485 486 ret &= ~HYM8563_CTL2_TI_TP; 487 488 return i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret); 489 } 490 491 #ifdef CONFIG_PM_SLEEP 492 static int hym8563_suspend(struct device *dev) 493 { 494 struct i2c_client *client = to_i2c_client(dev); 495 int ret; 496 497 if (device_may_wakeup(dev)) { 498 ret = enable_irq_wake(client->irq); 499 if (ret) { 500 dev_err(dev, "enable_irq_wake failed, %d\n", ret); 501 return ret; 502 } 503 } 504 505 return 0; 506 } 507 508 static int hym8563_resume(struct device *dev) 509 { 510 struct i2c_client *client = to_i2c_client(dev); 511 512 if (device_may_wakeup(dev)) 513 disable_irq_wake(client->irq); 514 515 return 0; 516 } 517 #endif 518 519 static SIMPLE_DEV_PM_OPS(hym8563_pm_ops, hym8563_suspend, hym8563_resume); 520 521 static int hym8563_probe(struct i2c_client *client, 522 const struct i2c_device_id *id) 523 { 524 struct hym8563 *hym8563; 525 int ret; 526 527 hym8563 = devm_kzalloc(&client->dev, sizeof(*hym8563), GFP_KERNEL); 528 if (!hym8563) 529 return -ENOMEM; 530 531 hym8563->client = client; 532 i2c_set_clientdata(client, hym8563); 533 534 device_set_wakeup_capable(&client->dev, true); 535 536 ret = hym8563_init_device(client); 537 if (ret) { 538 dev_err(&client->dev, "could not init device, %d\n", ret); 539 return ret; 540 } 541 542 if (client->irq > 0) { 543 ret = devm_request_threaded_irq(&client->dev, client->irq, 544 NULL, hym8563_irq, 545 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 546 client->name, hym8563); 547 if (ret < 0) { 548 dev_err(&client->dev, "irq %d request failed, %d\n", 549 client->irq, ret); 550 return ret; 551 } 552 } 553 554 /* check state of calendar information */ 555 ret = i2c_smbus_read_byte_data(client, HYM8563_SEC); 556 if (ret < 0) 557 return ret; 558 559 hym8563->valid = !(ret & HYM8563_SEC_VL); 560 dev_dbg(&client->dev, "rtc information is %s\n", 561 hym8563->valid ? "valid" : "invalid"); 562 563 hym8563->rtc = devm_rtc_device_register(&client->dev, client->name, 564 &hym8563_rtc_ops, THIS_MODULE); 565 if (IS_ERR(hym8563->rtc)) 566 return PTR_ERR(hym8563->rtc); 567 568 /* the hym8563 alarm only supports a minute accuracy */ 569 hym8563->rtc->uie_unsupported = 1; 570 571 #ifdef CONFIG_COMMON_CLK 572 hym8563_clkout_register_clk(hym8563); 573 #endif 574 575 return 0; 576 } 577 578 static const struct i2c_device_id hym8563_id[] = { 579 { "hym8563", 0 }, 580 {}, 581 }; 582 MODULE_DEVICE_TABLE(i2c, hym8563_id); 583 584 static const struct of_device_id hym8563_dt_idtable[] = { 585 { .compatible = "haoyu,hym8563" }, 586 {}, 587 }; 588 MODULE_DEVICE_TABLE(of, hym8563_dt_idtable); 589 590 static struct i2c_driver hym8563_driver = { 591 .driver = { 592 .name = "rtc-hym8563", 593 .pm = &hym8563_pm_ops, 594 .of_match_table = hym8563_dt_idtable, 595 }, 596 .probe = hym8563_probe, 597 .id_table = hym8563_id, 598 }; 599 600 module_i2c_driver(hym8563_driver); 601 602 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>"); 603 MODULE_DESCRIPTION("HYM8563 RTC driver"); 604 MODULE_LICENSE("GPL"); 605