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 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 224 if (ret < 0) 225 return ret; 226 227 ret &= ~HYM8563_CTL2_AIE; 228 229 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret); 230 if (ret < 0) 231 return ret; 232 233 buf[0] = (alm_tm->tm_min < 60 && alm_tm->tm_min >= 0) ? 234 bin2bcd(alm_tm->tm_min) : HYM8563_ALM_BIT_DISABLE; 235 236 buf[1] = (alm_tm->tm_hour < 24 && alm_tm->tm_hour >= 0) ? 237 bin2bcd(alm_tm->tm_hour) : HYM8563_ALM_BIT_DISABLE; 238 239 buf[2] = (alm_tm->tm_mday <= 31 && alm_tm->tm_mday >= 1) ? 240 bin2bcd(alm_tm->tm_mday) : HYM8563_ALM_BIT_DISABLE; 241 242 buf[3] = (alm_tm->tm_wday < 7 && alm_tm->tm_wday >= 0) ? 243 bin2bcd(alm_tm->tm_wday) : HYM8563_ALM_BIT_DISABLE; 244 245 ret = i2c_smbus_write_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf); 246 if (ret < 0) 247 return ret; 248 249 return hym8563_rtc_alarm_irq_enable(dev, alm->enabled); 250 } 251 252 static const struct rtc_class_ops hym8563_rtc_ops = { 253 .read_time = hym8563_rtc_read_time, 254 .set_time = hym8563_rtc_set_time, 255 .alarm_irq_enable = hym8563_rtc_alarm_irq_enable, 256 .read_alarm = hym8563_rtc_read_alarm, 257 .set_alarm = hym8563_rtc_set_alarm, 258 }; 259 260 /* 261 * Handling of the clkout 262 */ 263 264 #ifdef CONFIG_COMMON_CLK 265 #define clkout_hw_to_hym8563(_hw) container_of(_hw, struct hym8563, clkout_hw) 266 267 static int clkout_rates[] = { 268 32768, 269 1024, 270 32, 271 1, 272 }; 273 274 static unsigned long hym8563_clkout_recalc_rate(struct clk_hw *hw, 275 unsigned long parent_rate) 276 { 277 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 278 struct i2c_client *client = hym8563->client; 279 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 280 281 if (ret < 0) 282 return 0; 283 284 ret &= HYM8563_CLKOUT_MASK; 285 return clkout_rates[ret]; 286 } 287 288 static long hym8563_clkout_round_rate(struct clk_hw *hw, unsigned long rate, 289 unsigned long *prate) 290 { 291 int i; 292 293 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 294 if (clkout_rates[i] <= rate) 295 return clkout_rates[i]; 296 297 return 0; 298 } 299 300 static int hym8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate, 301 unsigned long parent_rate) 302 { 303 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 304 struct i2c_client *client = hym8563->client; 305 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 306 int i; 307 308 if (ret < 0) 309 return ret; 310 311 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 312 if (clkout_rates[i] == rate) { 313 ret &= ~HYM8563_CLKOUT_MASK; 314 ret |= i; 315 return i2c_smbus_write_byte_data(client, 316 HYM8563_CLKOUT, ret); 317 } 318 319 return -EINVAL; 320 } 321 322 static int hym8563_clkout_control(struct clk_hw *hw, bool enable) 323 { 324 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 325 struct i2c_client *client = hym8563->client; 326 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 327 328 if (ret < 0) 329 return ret; 330 331 if (enable) 332 ret |= HYM8563_CLKOUT_ENABLE; 333 else 334 ret &= ~HYM8563_CLKOUT_ENABLE; 335 336 return i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, ret); 337 } 338 339 static int hym8563_clkout_prepare(struct clk_hw *hw) 340 { 341 return hym8563_clkout_control(hw, 1); 342 } 343 344 static void hym8563_clkout_unprepare(struct clk_hw *hw) 345 { 346 hym8563_clkout_control(hw, 0); 347 } 348 349 static int hym8563_clkout_is_prepared(struct clk_hw *hw) 350 { 351 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 352 struct i2c_client *client = hym8563->client; 353 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 354 355 if (ret < 0) 356 return ret; 357 358 return !!(ret & HYM8563_CLKOUT_ENABLE); 359 } 360 361 static const struct clk_ops hym8563_clkout_ops = { 362 .prepare = hym8563_clkout_prepare, 363 .unprepare = hym8563_clkout_unprepare, 364 .is_prepared = hym8563_clkout_is_prepared, 365 .recalc_rate = hym8563_clkout_recalc_rate, 366 .round_rate = hym8563_clkout_round_rate, 367 .set_rate = hym8563_clkout_set_rate, 368 }; 369 370 static struct clk *hym8563_clkout_register_clk(struct hym8563 *hym8563) 371 { 372 struct i2c_client *client = hym8563->client; 373 struct device_node *node = client->dev.of_node; 374 struct clk *clk; 375 struct clk_init_data init; 376 int ret; 377 378 ret = i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, 379 0); 380 if (ret < 0) 381 return ERR_PTR(ret); 382 383 init.name = "hym8563-clkout"; 384 init.ops = &hym8563_clkout_ops; 385 init.flags = 0; 386 init.parent_names = NULL; 387 init.num_parents = 0; 388 hym8563->clkout_hw.init = &init; 389 390 /* optional override of the clockname */ 391 of_property_read_string(node, "clock-output-names", &init.name); 392 393 /* register the clock */ 394 clk = clk_register(&client->dev, &hym8563->clkout_hw); 395 396 if (!IS_ERR(clk)) 397 of_clk_add_provider(node, of_clk_src_simple_get, clk); 398 399 return clk; 400 } 401 #endif 402 403 /* 404 * The alarm interrupt is implemented as a level-low interrupt in the 405 * hym8563, while the timer interrupt uses a falling edge. 406 * We don't use the timer at all, so the interrupt is requested to 407 * use the level-low trigger. 408 */ 409 static irqreturn_t hym8563_irq(int irq, void *dev_id) 410 { 411 struct hym8563 *hym8563 = (struct hym8563 *)dev_id; 412 struct i2c_client *client = hym8563->client; 413 int data, ret; 414 415 rtc_lock(hym8563->rtc); 416 417 /* Clear the alarm flag */ 418 419 data = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 420 if (data < 0) { 421 dev_err(&client->dev, "%s: error reading i2c data %d\n", 422 __func__, data); 423 goto out; 424 } 425 426 data &= ~HYM8563_CTL2_AF; 427 428 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, data); 429 if (ret < 0) { 430 dev_err(&client->dev, "%s: error writing i2c data %d\n", 431 __func__, ret); 432 } 433 434 out: 435 rtc_unlock(hym8563->rtc); 436 return IRQ_HANDLED; 437 } 438 439 static int hym8563_init_device(struct i2c_client *client) 440 { 441 int ret; 442 443 /* Clear stop flag if present */ 444 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0); 445 if (ret < 0) 446 return ret; 447 448 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 449 if (ret < 0) 450 return ret; 451 452 /* Disable alarm and timer interrupts */ 453 ret &= ~HYM8563_CTL2_AIE; 454 ret &= ~HYM8563_CTL2_TIE; 455 456 /* Clear any pending alarm and timer flags */ 457 if (ret & HYM8563_CTL2_AF) 458 ret &= ~HYM8563_CTL2_AF; 459 460 if (ret & HYM8563_CTL2_TF) 461 ret &= ~HYM8563_CTL2_TF; 462 463 ret &= ~HYM8563_CTL2_TI_TP; 464 465 return i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret); 466 } 467 468 #ifdef CONFIG_PM_SLEEP 469 static int hym8563_suspend(struct device *dev) 470 { 471 struct i2c_client *client = to_i2c_client(dev); 472 int ret; 473 474 if (device_may_wakeup(dev)) { 475 ret = enable_irq_wake(client->irq); 476 if (ret) { 477 dev_err(dev, "enable_irq_wake failed, %d\n", ret); 478 return ret; 479 } 480 } 481 482 return 0; 483 } 484 485 static int hym8563_resume(struct device *dev) 486 { 487 struct i2c_client *client = to_i2c_client(dev); 488 489 if (device_may_wakeup(dev)) 490 disable_irq_wake(client->irq); 491 492 return 0; 493 } 494 #endif 495 496 static SIMPLE_DEV_PM_OPS(hym8563_pm_ops, hym8563_suspend, hym8563_resume); 497 498 static int hym8563_probe(struct i2c_client *client, 499 const struct i2c_device_id *id) 500 { 501 struct hym8563 *hym8563; 502 int ret; 503 504 hym8563 = devm_kzalloc(&client->dev, sizeof(*hym8563), GFP_KERNEL); 505 if (!hym8563) 506 return -ENOMEM; 507 508 hym8563->rtc = devm_rtc_allocate_device(&client->dev); 509 if (IS_ERR(hym8563->rtc)) 510 return PTR_ERR(hym8563->rtc); 511 512 hym8563->client = client; 513 i2c_set_clientdata(client, hym8563); 514 515 ret = hym8563_init_device(client); 516 if (ret) { 517 dev_err(&client->dev, "could not init device, %d\n", ret); 518 return ret; 519 } 520 521 if (client->irq > 0) { 522 ret = devm_request_threaded_irq(&client->dev, client->irq, 523 NULL, hym8563_irq, 524 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 525 client->name, hym8563); 526 if (ret < 0) { 527 dev_err(&client->dev, "irq %d request failed, %d\n", 528 client->irq, ret); 529 return ret; 530 } 531 } 532 533 if (client->irq > 0 || 534 device_property_read_bool(&client->dev, "wakeup-source")) { 535 device_init_wakeup(&client->dev, true); 536 } 537 538 /* check state of calendar information */ 539 ret = i2c_smbus_read_byte_data(client, HYM8563_SEC); 540 if (ret < 0) 541 return ret; 542 543 dev_dbg(&client->dev, "rtc information is %s\n", 544 (ret & HYM8563_SEC_VL) ? "invalid" : "valid"); 545 546 hym8563->rtc->ops = &hym8563_rtc_ops; 547 set_bit(RTC_FEATURE_ALARM_RES_MINUTE, hym8563->rtc->features); 548 clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, hym8563->rtc->features); 549 550 #ifdef CONFIG_COMMON_CLK 551 hym8563_clkout_register_clk(hym8563); 552 #endif 553 554 return devm_rtc_register_device(hym8563->rtc); 555 } 556 557 static const struct i2c_device_id hym8563_id[] = { 558 { "hym8563", 0 }, 559 {}, 560 }; 561 MODULE_DEVICE_TABLE(i2c, hym8563_id); 562 563 static const struct of_device_id hym8563_dt_idtable[] = { 564 { .compatible = "haoyu,hym8563" }, 565 {}, 566 }; 567 MODULE_DEVICE_TABLE(of, hym8563_dt_idtable); 568 569 static struct i2c_driver hym8563_driver = { 570 .driver = { 571 .name = "rtc-hym8563", 572 .pm = &hym8563_pm_ops, 573 .of_match_table = hym8563_dt_idtable, 574 }, 575 .probe = hym8563_probe, 576 .id_table = hym8563_id, 577 }; 578 579 module_i2c_driver(hym8563_driver); 580 581 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>"); 582 MODULE_DESCRIPTION("HYM8563 RTC driver"); 583 MODULE_LICENSE("GPL"); 584