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