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