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); 112 113 tm->tm_sec = bcd2bin(buf[0] & HYM8563_SEC_MASK); 114 tm->tm_min = bcd2bin(buf[1] & HYM8563_MIN_MASK); 115 tm->tm_hour = bcd2bin(buf[2] & HYM8563_HOUR_MASK); 116 tm->tm_mday = bcd2bin(buf[3] & HYM8563_DAY_MASK); 117 tm->tm_wday = bcd2bin(buf[4] & HYM8563_WEEKDAY_MASK); /* 0 = Sun */ 118 tm->tm_mon = bcd2bin(buf[5] & HYM8563_MONTH_MASK) - 1; /* 0 = Jan */ 119 tm->tm_year = bcd2bin(buf[6]) + 100; 120 121 return 0; 122 } 123 124 static int hym8563_rtc_set_time(struct device *dev, struct rtc_time *tm) 125 { 126 struct i2c_client *client = to_i2c_client(dev); 127 struct hym8563 *hym8563 = i2c_get_clientdata(client); 128 u8 buf[7]; 129 int ret; 130 131 /* Years >= 2100 are to far in the future, 19XX is to early */ 132 if (tm->tm_year < 100 || tm->tm_year >= 200) 133 return -EINVAL; 134 135 buf[0] = bin2bcd(tm->tm_sec); 136 buf[1] = bin2bcd(tm->tm_min); 137 buf[2] = bin2bcd(tm->tm_hour); 138 buf[3] = bin2bcd(tm->tm_mday); 139 buf[4] = bin2bcd(tm->tm_wday); 140 buf[5] = bin2bcd(tm->tm_mon + 1); 141 142 /* 143 * While the HYM8563 has a century flag in the month register, 144 * it does not seem to carry it over a subsequent write/read. 145 * So we'll limit ourself to 100 years, starting at 2000 for now. 146 */ 147 buf[6] = tm->tm_year - 100; 148 149 /* 150 * CTL1 only contains TEST-mode bits apart from stop, 151 * so no need to read the value first 152 */ 153 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 154 HYM8563_CTL1_STOP); 155 if (ret < 0) 156 return ret; 157 158 ret = i2c_smbus_write_i2c_block_data(client, HYM8563_SEC, 7, buf); 159 if (ret < 0) 160 return ret; 161 162 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0); 163 if (ret < 0) 164 return ret; 165 166 hym8563->valid = true; 167 168 return 0; 169 } 170 171 static int hym8563_rtc_alarm_irq_enable(struct device *dev, 172 unsigned int enabled) 173 { 174 struct i2c_client *client = to_i2c_client(dev); 175 int data; 176 177 data = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 178 if (data < 0) 179 return data; 180 181 if (enabled) 182 data |= HYM8563_CTL2_AIE; 183 else 184 data &= ~HYM8563_CTL2_AIE; 185 186 return i2c_smbus_write_byte_data(client, HYM8563_CTL2, data); 187 }; 188 189 static int hym8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) 190 { 191 struct i2c_client *client = to_i2c_client(dev); 192 struct rtc_time *alm_tm = &alm->time; 193 u8 buf[4]; 194 int ret; 195 196 ret = i2c_smbus_read_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf); 197 if (ret < 0) 198 return ret; 199 200 /* The alarm only has a minute accuracy */ 201 alm_tm->tm_sec = -1; 202 203 alm_tm->tm_min = (buf[0] & HYM8563_ALM_BIT_DISABLE) ? 204 -1 : 205 bcd2bin(buf[0] & HYM8563_MIN_MASK); 206 alm_tm->tm_hour = (buf[1] & HYM8563_ALM_BIT_DISABLE) ? 207 -1 : 208 bcd2bin(buf[1] & HYM8563_HOUR_MASK); 209 alm_tm->tm_mday = (buf[2] & HYM8563_ALM_BIT_DISABLE) ? 210 -1 : 211 bcd2bin(buf[2] & HYM8563_DAY_MASK); 212 alm_tm->tm_wday = (buf[3] & HYM8563_ALM_BIT_DISABLE) ? 213 -1 : 214 bcd2bin(buf[3] & HYM8563_WEEKDAY_MASK); 215 216 alm_tm->tm_mon = -1; 217 alm_tm->tm_year = -1; 218 219 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 220 if (ret < 0) 221 return ret; 222 223 if (ret & HYM8563_CTL2_AIE) 224 alm->enabled = 1; 225 226 return 0; 227 } 228 229 static int hym8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) 230 { 231 struct i2c_client *client = to_i2c_client(dev); 232 struct rtc_time *alm_tm = &alm->time; 233 u8 buf[4]; 234 int ret; 235 236 /* 237 * The alarm has no seconds so deal with it 238 */ 239 if (alm_tm->tm_sec) { 240 alm_tm->tm_sec = 0; 241 alm_tm->tm_min++; 242 if (alm_tm->tm_min >= 60) { 243 alm_tm->tm_min = 0; 244 alm_tm->tm_hour++; 245 if (alm_tm->tm_hour >= 24) { 246 alm_tm->tm_hour = 0; 247 alm_tm->tm_mday++; 248 if (alm_tm->tm_mday > 31) 249 alm_tm->tm_mday = 0; 250 } 251 } 252 } 253 254 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 255 if (ret < 0) 256 return ret; 257 258 ret &= ~HYM8563_CTL2_AIE; 259 260 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret); 261 if (ret < 0) 262 return ret; 263 264 buf[0] = (alm_tm->tm_min < 60 && alm_tm->tm_min >= 0) ? 265 bin2bcd(alm_tm->tm_min) : HYM8563_ALM_BIT_DISABLE; 266 267 buf[1] = (alm_tm->tm_hour < 24 && alm_tm->tm_hour >= 0) ? 268 bin2bcd(alm_tm->tm_hour) : HYM8563_ALM_BIT_DISABLE; 269 270 buf[2] = (alm_tm->tm_mday <= 31 && alm_tm->tm_mday >= 1) ? 271 bin2bcd(alm_tm->tm_mday) : HYM8563_ALM_BIT_DISABLE; 272 273 buf[3] = (alm_tm->tm_wday < 7 && alm_tm->tm_wday >= 0) ? 274 bin2bcd(alm_tm->tm_wday) : HYM8563_ALM_BIT_DISABLE; 275 276 ret = i2c_smbus_write_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf); 277 if (ret < 0) 278 return ret; 279 280 return hym8563_rtc_alarm_irq_enable(dev, alm->enabled); 281 } 282 283 static const struct rtc_class_ops hym8563_rtc_ops = { 284 .read_time = hym8563_rtc_read_time, 285 .set_time = hym8563_rtc_set_time, 286 .alarm_irq_enable = hym8563_rtc_alarm_irq_enable, 287 .read_alarm = hym8563_rtc_read_alarm, 288 .set_alarm = hym8563_rtc_set_alarm, 289 }; 290 291 /* 292 * Handling of the clkout 293 */ 294 295 #ifdef CONFIG_COMMON_CLK 296 #define clkout_hw_to_hym8563(_hw) container_of(_hw, struct hym8563, clkout_hw) 297 298 static int clkout_rates[] = { 299 32768, 300 1024, 301 32, 302 1, 303 }; 304 305 static unsigned long hym8563_clkout_recalc_rate(struct clk_hw *hw, 306 unsigned long parent_rate) 307 { 308 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 309 struct i2c_client *client = hym8563->client; 310 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 311 312 if (ret < 0) 313 return 0; 314 315 ret &= HYM8563_CLKOUT_MASK; 316 return clkout_rates[ret]; 317 } 318 319 static long hym8563_clkout_round_rate(struct clk_hw *hw, unsigned long rate, 320 unsigned long *prate) 321 { 322 int i; 323 324 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 325 if (clkout_rates[i] <= rate) 326 return clkout_rates[i]; 327 328 return 0; 329 } 330 331 static int hym8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate, 332 unsigned long parent_rate) 333 { 334 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 335 struct i2c_client *client = hym8563->client; 336 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 337 int i; 338 339 if (ret < 0) 340 return ret; 341 342 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 343 if (clkout_rates[i] == rate) { 344 ret &= ~HYM8563_CLKOUT_MASK; 345 ret |= i; 346 return i2c_smbus_write_byte_data(client, 347 HYM8563_CLKOUT, ret); 348 } 349 350 return -EINVAL; 351 } 352 353 static int hym8563_clkout_control(struct clk_hw *hw, bool enable) 354 { 355 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 356 struct i2c_client *client = hym8563->client; 357 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 358 359 if (ret < 0) 360 return ret; 361 362 if (enable) 363 ret |= HYM8563_CLKOUT_ENABLE; 364 else 365 ret &= ~HYM8563_CLKOUT_ENABLE; 366 367 return i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, ret); 368 } 369 370 static int hym8563_clkout_prepare(struct clk_hw *hw) 371 { 372 return hym8563_clkout_control(hw, 1); 373 } 374 375 static void hym8563_clkout_unprepare(struct clk_hw *hw) 376 { 377 hym8563_clkout_control(hw, 0); 378 } 379 380 static int hym8563_clkout_is_prepared(struct clk_hw *hw) 381 { 382 struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw); 383 struct i2c_client *client = hym8563->client; 384 int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT); 385 386 if (ret < 0) 387 return ret; 388 389 return !!(ret & HYM8563_CLKOUT_ENABLE); 390 } 391 392 static const struct clk_ops hym8563_clkout_ops = { 393 .prepare = hym8563_clkout_prepare, 394 .unprepare = hym8563_clkout_unprepare, 395 .is_prepared = hym8563_clkout_is_prepared, 396 .recalc_rate = hym8563_clkout_recalc_rate, 397 .round_rate = hym8563_clkout_round_rate, 398 .set_rate = hym8563_clkout_set_rate, 399 }; 400 401 static struct clk *hym8563_clkout_register_clk(struct hym8563 *hym8563) 402 { 403 struct i2c_client *client = hym8563->client; 404 struct device_node *node = client->dev.of_node; 405 struct clk *clk; 406 struct clk_init_data init; 407 int ret; 408 409 ret = i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, 410 0); 411 if (ret < 0) 412 return ERR_PTR(ret); 413 414 init.name = "hym8563-clkout"; 415 init.ops = &hym8563_clkout_ops; 416 init.flags = CLK_IS_ROOT; 417 init.parent_names = NULL; 418 init.num_parents = 0; 419 hym8563->clkout_hw.init = &init; 420 421 /* optional override of the clockname */ 422 of_property_read_string(node, "clock-output-names", &init.name); 423 424 /* register the clock */ 425 clk = clk_register(&client->dev, &hym8563->clkout_hw); 426 427 if (!IS_ERR(clk)) 428 of_clk_add_provider(node, of_clk_src_simple_get, clk); 429 430 return clk; 431 } 432 #endif 433 434 /* 435 * The alarm interrupt is implemented as a level-low interrupt in the 436 * hym8563, while the timer interrupt uses a falling edge. 437 * We don't use the timer at all, so the interrupt is requested to 438 * use the level-low trigger. 439 */ 440 static irqreturn_t hym8563_irq(int irq, void *dev_id) 441 { 442 struct hym8563 *hym8563 = (struct hym8563 *)dev_id; 443 struct i2c_client *client = hym8563->client; 444 struct mutex *lock = &hym8563->rtc->ops_lock; 445 int data, ret; 446 447 mutex_lock(lock); 448 449 /* Clear the alarm flag */ 450 451 data = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 452 if (data < 0) { 453 dev_err(&client->dev, "%s: error reading i2c data %d\n", 454 __func__, data); 455 goto out; 456 } 457 458 data &= ~HYM8563_CTL2_AF; 459 460 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, data); 461 if (ret < 0) { 462 dev_err(&client->dev, "%s: error writing i2c data %d\n", 463 __func__, ret); 464 } 465 466 out: 467 mutex_unlock(lock); 468 return IRQ_HANDLED; 469 } 470 471 static int hym8563_init_device(struct i2c_client *client) 472 { 473 int ret; 474 475 /* Clear stop flag if present */ 476 ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0); 477 if (ret < 0) 478 return ret; 479 480 ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2); 481 if (ret < 0) 482 return ret; 483 484 /* Disable alarm and timer interrupts */ 485 ret &= ~HYM8563_CTL2_AIE; 486 ret &= ~HYM8563_CTL2_TIE; 487 488 /* Clear any pending alarm and timer flags */ 489 if (ret & HYM8563_CTL2_AF) 490 ret &= ~HYM8563_CTL2_AF; 491 492 if (ret & HYM8563_CTL2_TF) 493 ret &= ~HYM8563_CTL2_TF; 494 495 ret &= ~HYM8563_CTL2_TI_TP; 496 497 return i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret); 498 } 499 500 #ifdef CONFIG_PM_SLEEP 501 static int hym8563_suspend(struct device *dev) 502 { 503 struct i2c_client *client = to_i2c_client(dev); 504 int ret; 505 506 if (device_may_wakeup(dev)) { 507 ret = enable_irq_wake(client->irq); 508 if (ret) { 509 dev_err(dev, "enable_irq_wake failed, %d\n", ret); 510 return ret; 511 } 512 } 513 514 return 0; 515 } 516 517 static int hym8563_resume(struct device *dev) 518 { 519 struct i2c_client *client = to_i2c_client(dev); 520 521 if (device_may_wakeup(dev)) 522 disable_irq_wake(client->irq); 523 524 return 0; 525 } 526 #endif 527 528 static SIMPLE_DEV_PM_OPS(hym8563_pm_ops, hym8563_suspend, hym8563_resume); 529 530 static int hym8563_probe(struct i2c_client *client, 531 const struct i2c_device_id *id) 532 { 533 struct hym8563 *hym8563; 534 int ret; 535 536 hym8563 = devm_kzalloc(&client->dev, sizeof(*hym8563), GFP_KERNEL); 537 if (!hym8563) 538 return -ENOMEM; 539 540 hym8563->client = client; 541 i2c_set_clientdata(client, hym8563); 542 543 device_set_wakeup_capable(&client->dev, true); 544 545 ret = hym8563_init_device(client); 546 if (ret) { 547 dev_err(&client->dev, "could not init device, %d\n", ret); 548 return ret; 549 } 550 551 if (client->irq > 0) { 552 ret = devm_request_threaded_irq(&client->dev, client->irq, 553 NULL, hym8563_irq, 554 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 555 client->name, hym8563); 556 if (ret < 0) { 557 dev_err(&client->dev, "irq %d request failed, %d\n", 558 client->irq, ret); 559 return ret; 560 } 561 } 562 563 /* check state of calendar information */ 564 ret = i2c_smbus_read_byte_data(client, HYM8563_SEC); 565 if (ret < 0) 566 return ret; 567 568 hym8563->valid = !(ret & HYM8563_SEC_VL); 569 dev_dbg(&client->dev, "rtc information is %s\n", 570 hym8563->valid ? "valid" : "invalid"); 571 572 hym8563->rtc = devm_rtc_device_register(&client->dev, client->name, 573 &hym8563_rtc_ops, THIS_MODULE); 574 if (IS_ERR(hym8563->rtc)) 575 return PTR_ERR(hym8563->rtc); 576 577 /* the hym8563 alarm only supports a minute accuracy */ 578 hym8563->rtc->uie_unsupported = 1; 579 580 #ifdef CONFIG_COMMON_CLK 581 hym8563_clkout_register_clk(hym8563); 582 #endif 583 584 return 0; 585 } 586 587 static const struct i2c_device_id hym8563_id[] = { 588 { "hym8563", 0 }, 589 {}, 590 }; 591 MODULE_DEVICE_TABLE(i2c, hym8563_id); 592 593 static const struct of_device_id hym8563_dt_idtable[] = { 594 { .compatible = "haoyu,hym8563" }, 595 {}, 596 }; 597 MODULE_DEVICE_TABLE(of, hym8563_dt_idtable); 598 599 static struct i2c_driver hym8563_driver = { 600 .driver = { 601 .name = "rtc-hym8563", 602 .owner = THIS_MODULE, 603 .pm = &hym8563_pm_ops, 604 .of_match_table = hym8563_dt_idtable, 605 }, 606 .probe = hym8563_probe, 607 .id_table = hym8563_id, 608 }; 609 610 module_i2c_driver(hym8563_driver); 611 612 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>"); 613 MODULE_DESCRIPTION("HYM8563 RTC driver"); 614 MODULE_LICENSE("GPL"); 615