1 /* 2 * Haoyu HYM8563 RTC driver 3 * 4 * Copyright (C) 2013 MundoReader S.L. 5 * Author: Heiko Stuebner <heiko@sntech.de> 6 * 7 * based on rtc-HYM8563 8 * Copyright (C) 2010 ROCKCHIP, Inc. 9 * 10 * This software is licensed under the terms of the GNU General Public 11 * License version 2, as published by the Free Software Foundation, and 12 * may be copied, distributed, and modified under those terms. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 */ 19 20 #include <linux/module.h> 21 #include <linux/clk-provider.h> 22 #include <linux/i2c.h> 23 #include <linux/bcd.h> 24 #include <linux/rtc.h> 25 26 #define HYM8563_CTL1 0x00 27 #define HYM8563_CTL1_TEST BIT(7) 28 #define HYM8563_CTL1_STOP BIT(5) 29 #define HYM8563_CTL1_TESTC BIT(3) 30 31 #define HYM8563_CTL2 0x01 32 #define HYM8563_CTL2_TI_TP BIT(4) 33 #define HYM8563_CTL2_AF BIT(3) 34 #define HYM8563_CTL2_TF BIT(2) 35 #define HYM8563_CTL2_AIE BIT(1) 36 #define HYM8563_CTL2_TIE BIT(0) 37 38 #define HYM8563_SEC 0x02 39 #define HYM8563_SEC_VL BIT(7) 40 #define HYM8563_SEC_MASK 0x7f 41 42 #define HYM8563_MIN 0x03 43 #define HYM8563_MIN_MASK 0x7f 44 45 #define HYM8563_HOUR 0x04 46 #define HYM8563_HOUR_MASK 0x3f 47 48 #define HYM8563_DAY 0x05 49 #define HYM8563_DAY_MASK 0x3f 50 51 #define HYM8563_WEEKDAY 0x06 52 #define HYM8563_WEEKDAY_MASK 0x07 53 54 #define HYM8563_MONTH 0x07 55 #define HYM8563_MONTH_CENTURY BIT(7) 56 #define HYM8563_MONTH_MASK 0x1f 57 58 #define HYM8563_YEAR 0x08 59 60 #define HYM8563_ALM_MIN 0x09 61 #define HYM8563_ALM_HOUR 0x0a 62 #define HYM8563_ALM_DAY 0x0b 63 #define HYM8563_ALM_WEEK 0x0c 64 65 /* Each alarm check can be disabled by setting this bit in the register */ 66 #define HYM8563_ALM_BIT_DISABLE BIT(7) 67 68 #define HYM8563_CLKOUT 0x0d 69 #define HYM8563_CLKOUT_ENABLE BIT(7) 70 #define HYM8563_CLKOUT_32768 0 71 #define HYM8563_CLKOUT_1024 1 72 #define HYM8563_CLKOUT_32 2 73 #define HYM8563_CLKOUT_1 3 74 #define HYM8563_CLKOUT_MASK 3 75 76 #define HYM8563_TMR_CTL 0x0e 77 #define HYM8563_TMR_CTL_ENABLE BIT(7) 78 #define HYM8563_TMR_CTL_4096 0 79 #define HYM8563_TMR_CTL_64 1 80 #define HYM8563_TMR_CTL_1 2 81 #define HYM8563_TMR_CTL_1_60 3 82 #define HYM8563_TMR_CTL_MASK 3 83 84 #define HYM8563_TMR_CNT 0x0f 85 86 struct hym8563 { 87 struct i2c_client *client; 88 struct rtc_device *rtc; 89 bool valid; 90 #ifdef CONFIG_COMMON_CLK 91 struct clk_hw clkout_hw; 92 #endif 93 }; 94 95 /* 96 * RTC handling 97 */ 98 99 static int hym8563_rtc_read_time(struct device *dev, struct rtc_time *tm) 100 { 101 struct i2c_client *client = to_i2c_client(dev); 102 struct hym8563 *hym8563 = i2c_get_clientdata(client); 103 u8 buf[7]; 104 int ret; 105 106 if (!hym8563->valid) { 107 dev_warn(&client->dev, "no valid clock/calendar values available\n"); 108 return -EPERM; 109 } 110 111 ret = i2c_smbus_read_i2c_block_data(client, HYM8563_SEC, 7, buf); 112 if (ret < 0) 113 return ret; 114 115 tm->tm_sec = bcd2bin(buf[0] & HYM8563_SEC_MASK); 116 tm->tm_min = bcd2bin(buf[1] & HYM8563_MIN_MASK); 117 tm->tm_hour = bcd2bin(buf[2] & HYM8563_HOUR_MASK); 118 tm->tm_mday = bcd2bin(buf[3] & HYM8563_DAY_MASK); 119 tm->tm_wday = bcd2bin(buf[4] & HYM8563_WEEKDAY_MASK); /* 0 = Sun */ 120 tm->tm_mon = bcd2bin(buf[5] & HYM8563_MONTH_MASK) - 1; /* 0 = Jan */ 121 tm->tm_year = bcd2bin(buf[6]) + 100; 122 123 return 0; 124 } 125 126 static int hym8563_rtc_set_time(struct device *dev, struct rtc_time *tm) 127 { 128 struct i2c_client *client = to_i2c_client(dev); 129 struct hym8563 *hym8563 = i2c_get_clientdata(client); 130 u8 buf[7]; 131 int ret; 132 133 /* Years >= 2100 are to far in the future, 19XX is to early */ 134 if (tm->tm_year < 100 || tm->tm_year >= 200) 135 return -EINVAL; 136 137 buf[0] = bin2bcd(tm->tm_sec); 138 buf[1] = bin2bcd(tm->tm_min); 139 buf[2] = bin2bcd(tm->tm_hour); 140 buf[3] = bin2bcd(tm->tm_mday); 141 buf[4] = bin2bcd(tm->tm_wday); 142 buf[5] = bin2bcd(tm->tm_mon + 1); 143 144 /* 145 * While the HYM8563 has a century flag in the month register, 146 * it does not seem to carry it over a subsequent write/read. 147 * So we'll limit ourself to 100 years, starting at 2000 for now. 148 */ 149 buf[6] = bin2bcd(tm->tm_year - 100); 150 151 /* 152 * CTL1 only contains TEST-mode bits apart from stop, 153 * so no need to read the value first 154 */ 155 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 156 HYM8563_CTL1_STOP); 157 if (ret < 0) 158 return ret; 159 160 ret = i2c_smbus_write_i2c_block_data(client, HYM8563_SEC, 7, buf); 161 if (ret < 0) 162 return ret; 163 164 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0); 165 if (ret < 0) 166 return ret; 167 168 hym8563->valid = true; 169 170 return 0; 171 } 172 173 static int hym8563_rtc_alarm_irq_enable(struct device *dev, 174 unsigned int enabled) 175 { 176 struct i2c_client *client = to_i2c_client(dev); 177 int data; 178 179 data = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 180 if (data < 0) 181 return data; 182 183 if (enabled) 184 data |= HYM8563_CTL2_AIE; 185 else 186 data &= ~HYM8563_CTL2_AIE; 187 188 return i2c_smbus_write_byte_data(client, HYM8563_CTL2, data); 189 }; 190 191 static int hym8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) 192 { 193 struct i2c_client *client = to_i2c_client(dev); 194 struct rtc_time *alm_tm = &alm->time; 195 u8 buf[4]; 196 int ret; 197 198 ret = i2c_smbus_read_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf); 199 if (ret < 0) 200 return ret; 201 202 /* The alarm only has a minute accuracy */ 203 alm_tm->tm_sec = 0; 204 205 alm_tm->tm_min = (buf[0] & HYM8563_ALM_BIT_DISABLE) ? 206 -1 : 207 bcd2bin(buf[0] & HYM8563_MIN_MASK); 208 alm_tm->tm_hour = (buf[1] & HYM8563_ALM_BIT_DISABLE) ? 209 -1 : 210 bcd2bin(buf[1] & HYM8563_HOUR_MASK); 211 alm_tm->tm_mday = (buf[2] & HYM8563_ALM_BIT_DISABLE) ? 212 -1 : 213 bcd2bin(buf[2] & HYM8563_DAY_MASK); 214 alm_tm->tm_wday = (buf[3] & HYM8563_ALM_BIT_DISABLE) ? 215 -1 : 216 bcd2bin(buf[3] & HYM8563_WEEKDAY_MASK); 217 218 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 219 if (ret < 0) 220 return ret; 221 222 if (ret & HYM8563_CTL2_AIE) 223 alm->enabled = 1; 224 225 return 0; 226 } 227 228 static int hym8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) 229 { 230 struct i2c_client *client = to_i2c_client(dev); 231 struct rtc_time *alm_tm = &alm->time; 232 u8 buf[4]; 233 int ret; 234 235 /* 236 * The alarm has no seconds so deal with it 237 */ 238 if (alm_tm->tm_sec) { 239 alm_tm->tm_sec = 0; 240 alm_tm->tm_min++; 241 if (alm_tm->tm_min >= 60) { 242 alm_tm->tm_min = 0; 243 alm_tm->tm_hour++; 244 if (alm_tm->tm_hour >= 24) { 245 alm_tm->tm_hour = 0; 246 alm_tm->tm_mday++; 247 if (alm_tm->tm_mday > 31) 248 alm_tm->tm_mday = 0; 249 } 250 } 251 } 252 253 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 254 if (ret < 0) 255 return ret; 256 257 ret &= ~HYM8563_CTL2_AIE; 258 259 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret); 260 if (ret < 0) 261 return ret; 262 263 buf[0] = (alm_tm->tm_min < 60 && alm_tm->tm_min >= 0) ? 264 bin2bcd(alm_tm->tm_min) : HYM8563_ALM_BIT_DISABLE; 265 266 buf[1] = (alm_tm->tm_hour < 24 && alm_tm->tm_hour >= 0) ? 267 bin2bcd(alm_tm->tm_hour) : HYM8563_ALM_BIT_DISABLE; 268 269 buf[2] = (alm_tm->tm_mday <= 31 && alm_tm->tm_mday >= 1) ? 270 bin2bcd(alm_tm->tm_mday) : HYM8563_ALM_BIT_DISABLE; 271 272 buf[3] = (alm_tm->tm_wday < 7 && alm_tm->tm_wday >= 0) ? 273 bin2bcd(alm_tm->tm_wday) : HYM8563_ALM_BIT_DISABLE; 274 275 ret = i2c_smbus_write_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf); 276 if (ret < 0) 277 return ret; 278 279 return hym8563_rtc_alarm_irq_enable(dev, alm->enabled); 280 } 281 282 static const struct rtc_class_ops hym8563_rtc_ops = { 283 .read_time = hym8563_rtc_read_time, 284 .set_time = hym8563_rtc_set_time, 285 .alarm_irq_enable = hym8563_rtc_alarm_irq_enable, 286 .read_alarm = hym8563_rtc_read_alarm, 287 .set_alarm = hym8563_rtc_set_alarm, 288 }; 289 290 /* 291 * Handling of the clkout 292 */ 293 294 #ifdef CONFIG_COMMON_CLK 295 #define clkout_hw_to_hym8563(_hw) container_of(_hw, struct hym8563, clkout_hw) 296 297 static int clkout_rates[] = { 298 32768, 299 1024, 300 32, 301 1, 302 }; 303 304 static unsigned long hym8563_clkout_recalc_rate(struct clk_hw *hw, 305 unsigned long parent_rate) 306 { 307 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 308 struct i2c_client *client = hym8563->client; 309 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 310 311 if (ret < 0) 312 return 0; 313 314 ret &= HYM8563_CLKOUT_MASK; 315 return clkout_rates[ret]; 316 } 317 318 static long hym8563_clkout_round_rate(struct clk_hw *hw, unsigned long rate, 319 unsigned long *prate) 320 { 321 int i; 322 323 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 324 if (clkout_rates[i] <= rate) 325 return clkout_rates[i]; 326 327 return 0; 328 } 329 330 static int hym8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate, 331 unsigned long parent_rate) 332 { 333 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 334 struct i2c_client *client = hym8563->client; 335 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 336 int i; 337 338 if (ret < 0) 339 return ret; 340 341 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 342 if (clkout_rates[i] == rate) { 343 ret &= ~HYM8563_CLKOUT_MASK; 344 ret |= i; 345 return i2c_smbus_write_byte_data(client, 346 HYM8563_CLKOUT, ret); 347 } 348 349 return -EINVAL; 350 } 351 352 static int hym8563_clkout_control(struct clk_hw *hw, bool enable) 353 { 354 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 355 struct i2c_client *client = hym8563->client; 356 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 357 358 if (ret < 0) 359 return ret; 360 361 if (enable) 362 ret |= HYM8563_CLKOUT_ENABLE; 363 else 364 ret &= ~HYM8563_CLKOUT_ENABLE; 365 366 return i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, ret); 367 } 368 369 static int hym8563_clkout_prepare(struct clk_hw *hw) 370 { 371 return hym8563_clkout_control(hw, 1); 372 } 373 374 static void hym8563_clkout_unprepare(struct clk_hw *hw) 375 { 376 hym8563_clkout_control(hw, 0); 377 } 378 379 static int hym8563_clkout_is_prepared(struct clk_hw *hw) 380 { 381 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 382 struct i2c_client *client = hym8563->client; 383 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 384 385 if (ret < 0) 386 return ret; 387 388 return !!(ret & HYM8563_CLKOUT_ENABLE); 389 } 390 391 static const struct clk_ops hym8563_clkout_ops = { 392 .prepare = hym8563_clkout_prepare, 393 .unprepare = hym8563_clkout_unprepare, 394 .is_prepared = hym8563_clkout_is_prepared, 395 .recalc_rate = hym8563_clkout_recalc_rate, 396 .round_rate = hym8563_clkout_round_rate, 397 .set_rate = hym8563_clkout_set_rate, 398 }; 399 400 static struct clk *hym8563_clkout_register_clk(struct hym8563 *hym8563) 401 { 402 struct i2c_client *client = hym8563->client; 403 struct device_node *node = client->dev.of_node; 404 struct clk *clk; 405 struct clk_init_data init; 406 int ret; 407 408 ret = i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, 409 0); 410 if (ret < 0) 411 return ERR_PTR(ret); 412 413 init.name = "hym8563-clkout"; 414 init.ops = &hym8563_clkout_ops; 415 init.flags = 0; 416 init.parent_names = NULL; 417 init.num_parents = 0; 418 hym8563->clkout_hw.init = &init; 419 420 /* optional override of the clockname */ 421 of_property_read_string(node, "clock-output-names", &init.name); 422 423 /* register the clock */ 424 clk = clk_register(&client->dev, &hym8563->clkout_hw); 425 426 if (!IS_ERR(clk)) 427 of_clk_add_provider(node, of_clk_src_simple_get, clk); 428 429 return clk; 430 } 431 #endif 432 433 /* 434 * The alarm interrupt is implemented as a level-low interrupt in the 435 * hym8563, while the timer interrupt uses a falling edge. 436 * We don't use the timer at all, so the interrupt is requested to 437 * use the level-low trigger. 438 */ 439 static irqreturn_t hym8563_irq(int irq, void *dev_id) 440 { 441 struct hym8563 *hym8563 = (struct hym8563 *)dev_id; 442 struct i2c_client *client = hym8563->client; 443 struct mutex *lock = &hym8563->rtc->ops_lock; 444 int data, ret; 445 446 mutex_lock(lock); 447 448 /* Clear the alarm flag */ 449 450 data = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 451 if (data < 0) { 452 dev_err(&client->dev, "%s: error reading i2c data %d\n", 453 __func__, data); 454 goto out; 455 } 456 457 data &= ~HYM8563_CTL2_AF; 458 459 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, data); 460 if (ret < 0) { 461 dev_err(&client->dev, "%s: error writing i2c data %d\n", 462 __func__, ret); 463 } 464 465 out: 466 mutex_unlock(lock); 467 return IRQ_HANDLED; 468 } 469 470 static int hym8563_init_device(struct i2c_client *client) 471 { 472 int ret; 473 474 /* Clear stop flag if present */ 475 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0); 476 if (ret < 0) 477 return ret; 478 479 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 480 if (ret < 0) 481 return ret; 482 483 /* Disable alarm and timer interrupts */ 484 ret &= ~HYM8563_CTL2_AIE; 485 ret &= ~HYM8563_CTL2_TIE; 486 487 /* Clear any pending alarm and timer flags */ 488 if (ret & HYM8563_CTL2_AF) 489 ret &= ~HYM8563_CTL2_AF; 490 491 if (ret & HYM8563_CTL2_TF) 492 ret &= ~HYM8563_CTL2_TF; 493 494 ret &= ~HYM8563_CTL2_TI_TP; 495 496 return i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret); 497 } 498 499 #ifdef CONFIG_PM_SLEEP 500 static int hym8563_suspend(struct device *dev) 501 { 502 struct i2c_client *client = to_i2c_client(dev); 503 int ret; 504 505 if (device_may_wakeup(dev)) { 506 ret = enable_irq_wake(client->irq); 507 if (ret) { 508 dev_err(dev, "enable_irq_wake failed, %d\n", ret); 509 return ret; 510 } 511 } 512 513 return 0; 514 } 515 516 static int hym8563_resume(struct device *dev) 517 { 518 struct i2c_client *client = to_i2c_client(dev); 519 520 if (device_may_wakeup(dev)) 521 disable_irq_wake(client->irq); 522 523 return 0; 524 } 525 #endif 526 527 static SIMPLE_DEV_PM_OPS(hym8563_pm_ops, hym8563_suspend, hym8563_resume); 528 529 static int hym8563_probe(struct i2c_client *client, 530 const struct i2c_device_id *id) 531 { 532 struct hym8563 *hym8563; 533 int ret; 534 535 hym8563 = devm_kzalloc(&client->dev, sizeof(*hym8563), GFP_KERNEL); 536 if (!hym8563) 537 return -ENOMEM; 538 539 hym8563->client = client; 540 i2c_set_clientdata(client, hym8563); 541 542 device_set_wakeup_capable(&client->dev, true); 543 544 ret = hym8563_init_device(client); 545 if (ret) { 546 dev_err(&client->dev, "could not init device, %d\n", ret); 547 return ret; 548 } 549 550 if (client->irq > 0) { 551 ret = devm_request_threaded_irq(&client->dev, client->irq, 552 NULL, hym8563_irq, 553 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 554 client->name, hym8563); 555 if (ret < 0) { 556 dev_err(&client->dev, "irq %d request failed, %d\n", 557 client->irq, ret); 558 return ret; 559 } 560 } 561 562 /* check state of calendar information */ 563 ret = i2c_smbus_read_byte_data(client, HYM8563_SEC); 564 if (ret < 0) 565 return ret; 566 567 hym8563->valid = !(ret & HYM8563_SEC_VL); 568 dev_dbg(&client->dev, "rtc information is %s\n", 569 hym8563->valid ? "valid" : "invalid"); 570 571 hym8563->rtc = devm_rtc_device_register(&client->dev, client->name, 572 &hym8563_rtc_ops, THIS_MODULE); 573 if (IS_ERR(hym8563->rtc)) 574 return PTR_ERR(hym8563->rtc); 575 576 /* the hym8563 alarm only supports a minute accuracy */ 577 hym8563->rtc->uie_unsupported = 1; 578 579 #ifdef CONFIG_COMMON_CLK 580 hym8563_clkout_register_clk(hym8563); 581 #endif 582 583 return 0; 584 } 585 586 static const struct i2c_device_id hym8563_id[] = { 587 { "hym8563", 0 }, 588 {}, 589 }; 590 MODULE_DEVICE_TABLE(i2c, hym8563_id); 591 592 static const struct of_device_id hym8563_dt_idtable[] = { 593 { .compatible = "haoyu,hym8563" }, 594 {}, 595 }; 596 MODULE_DEVICE_TABLE(of, hym8563_dt_idtable); 597 598 static struct i2c_driver hym8563_driver = { 599 .driver = { 600 .name = "rtc-hym8563", 601 .pm = &hym8563_pm_ops, 602 .of_match_table = hym8563_dt_idtable, 603 }, 604 .probe = hym8563_probe, 605 .id_table = hym8563_id, 606 }; 607 608 module_i2c_driver(hym8563_driver); 609 610 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>"); 611 MODULE_DESCRIPTION("HYM8563 RTC driver"); 612 MODULE_LICENSE("GPL"); 613