1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * An I2C driver for the Philips PCF8563 RTC 4 * Copyright 2005-06 Tower Technologies 5 * 6 * Author: Alessandro Zummo <a.zummo@towertech.it> 7 * Maintainers: http://www.nslu2-linux.org/ 8 * 9 * based on the other drivers in this same directory. 10 * 11 * http://www.semiconductors.philips.com/acrobat/datasheets/PCF8563-04.pdf 12 */ 13 14 #include <linux/clk-provider.h> 15 #include <linux/i2c.h> 16 #include <linux/bcd.h> 17 #include <linux/rtc.h> 18 #include <linux/slab.h> 19 #include <linux/module.h> 20 #include <linux/of.h> 21 #include <linux/err.h> 22 23 #define PCF8563_REG_ST1 0x00 /* status */ 24 #define PCF8563_REG_ST2 0x01 25 #define PCF8563_BIT_AIE (1 << 1) 26 #define PCF8563_BIT_AF (1 << 3) 27 #define PCF8563_BITS_ST2_N (7 << 5) 28 29 #define PCF8563_REG_SC 0x02 /* datetime */ 30 #define PCF8563_REG_MN 0x03 31 #define PCF8563_REG_HR 0x04 32 #define PCF8563_REG_DM 0x05 33 #define PCF8563_REG_DW 0x06 34 #define PCF8563_REG_MO 0x07 35 #define PCF8563_REG_YR 0x08 36 37 #define PCF8563_REG_AMN 0x09 /* alarm */ 38 39 #define PCF8563_REG_CLKO 0x0D /* clock out */ 40 #define PCF8563_REG_CLKO_FE 0x80 /* clock out enabled */ 41 #define PCF8563_REG_CLKO_F_MASK 0x03 /* frequenc mask */ 42 #define PCF8563_REG_CLKO_F_32768HZ 0x00 43 #define PCF8563_REG_CLKO_F_1024HZ 0x01 44 #define PCF8563_REG_CLKO_F_32HZ 0x02 45 #define PCF8563_REG_CLKO_F_1HZ 0x03 46 47 #define PCF8563_REG_TMRC 0x0E /* timer control */ 48 #define PCF8563_TMRC_ENABLE BIT(7) 49 #define PCF8563_TMRC_4096 0 50 #define PCF8563_TMRC_64 1 51 #define PCF8563_TMRC_1 2 52 #define PCF8563_TMRC_1_60 3 53 #define PCF8563_TMRC_MASK 3 54 55 #define PCF8563_REG_TMR 0x0F /* timer */ 56 57 #define PCF8563_SC_LV 0x80 /* low voltage */ 58 #define PCF8563_MO_C 0x80 /* century */ 59 60 static struct i2c_driver pcf8563_driver; 61 62 struct pcf8563 { 63 struct rtc_device *rtc; 64 /* 65 * The meaning of MO_C bit varies by the chip type. 66 * From PCF8563 datasheet: this bit is toggled when the years 67 * register overflows from 99 to 00 68 * 0 indicates the century is 20xx 69 * 1 indicates the century is 19xx 70 * From RTC8564 datasheet: this bit indicates change of 71 * century. When the year digit data overflows from 99 to 00, 72 * this bit is set. By presetting it to 0 while still in the 73 * 20th century, it will be set in year 2000, ... 74 * There seems no reliable way to know how the system use this 75 * bit. So let's do it heuristically, assuming we are live in 76 * 1970...2069. 77 */ 78 int c_polarity; /* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */ 79 int voltage_low; /* incicates if a low_voltage was detected */ 80 81 struct i2c_client *client; 82 #ifdef CONFIG_COMMON_CLK 83 struct clk_hw clkout_hw; 84 #endif 85 }; 86 87 static int pcf8563_read_block_data(struct i2c_client *client, unsigned char reg, 88 unsigned char length, unsigned char *buf) 89 { 90 struct i2c_msg msgs[] = { 91 {/* setup read ptr */ 92 .addr = client->addr, 93 .len = 1, 94 .buf = ®, 95 }, 96 { 97 .addr = client->addr, 98 .flags = I2C_M_RD, 99 .len = length, 100 .buf = buf 101 }, 102 }; 103 104 if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { 105 dev_err(&client->dev, "%s: read error\n", __func__); 106 return -EIO; 107 } 108 109 return 0; 110 } 111 112 static int pcf8563_write_block_data(struct i2c_client *client, 113 unsigned char reg, unsigned char length, 114 unsigned char *buf) 115 { 116 int i, err; 117 118 for (i = 0; i < length; i++) { 119 unsigned char data[2] = { reg + i, buf[i] }; 120 121 err = i2c_master_send(client, data, sizeof(data)); 122 if (err != sizeof(data)) { 123 dev_err(&client->dev, 124 "%s: err=%d addr=%02x, data=%02x\n", 125 __func__, err, data[0], data[1]); 126 return -EIO; 127 } 128 } 129 130 return 0; 131 } 132 133 static int pcf8563_set_alarm_mode(struct i2c_client *client, bool on) 134 { 135 unsigned char buf; 136 int err; 137 138 err = pcf8563_read_block_data(client, PCF8563_REG_ST2, 1, &buf); 139 if (err < 0) 140 return err; 141 142 if (on) 143 buf |= PCF8563_BIT_AIE; 144 else 145 buf &= ~PCF8563_BIT_AIE; 146 147 buf &= ~(PCF8563_BIT_AF | PCF8563_BITS_ST2_N); 148 149 err = pcf8563_write_block_data(client, PCF8563_REG_ST2, 1, &buf); 150 if (err < 0) { 151 dev_err(&client->dev, "%s: write error\n", __func__); 152 return -EIO; 153 } 154 155 return 0; 156 } 157 158 static int pcf8563_get_alarm_mode(struct i2c_client *client, unsigned char *en, 159 unsigned char *pen) 160 { 161 unsigned char buf; 162 int err; 163 164 err = pcf8563_read_block_data(client, PCF8563_REG_ST2, 1, &buf); 165 if (err) 166 return err; 167 168 if (en) 169 *en = !!(buf & PCF8563_BIT_AIE); 170 if (pen) 171 *pen = !!(buf & PCF8563_BIT_AF); 172 173 return 0; 174 } 175 176 static irqreturn_t pcf8563_irq(int irq, void *dev_id) 177 { 178 struct pcf8563 *pcf8563 = i2c_get_clientdata(dev_id); 179 int err; 180 char pending; 181 182 err = pcf8563_get_alarm_mode(pcf8563->client, NULL, &pending); 183 if (err) 184 return IRQ_NONE; 185 186 if (pending) { 187 rtc_update_irq(pcf8563->rtc, 1, RTC_IRQF | RTC_AF); 188 pcf8563_set_alarm_mode(pcf8563->client, 1); 189 return IRQ_HANDLED; 190 } 191 192 return IRQ_NONE; 193 } 194 195 /* 196 * In the routines that deal directly with the pcf8563 hardware, we use 197 * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch. 198 */ 199 static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm) 200 { 201 struct pcf8563 *pcf8563 = i2c_get_clientdata(client); 202 unsigned char buf[9]; 203 int err; 204 205 err = pcf8563_read_block_data(client, PCF8563_REG_ST1, 9, buf); 206 if (err) 207 return err; 208 209 if (buf[PCF8563_REG_SC] & PCF8563_SC_LV) { 210 pcf8563->voltage_low = 1; 211 dev_err(&client->dev, 212 "low voltage detected, date/time is not reliable.\n"); 213 return -EINVAL; 214 } 215 216 dev_dbg(&client->dev, 217 "%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, " 218 "mday=%02x, wday=%02x, mon=%02x, year=%02x\n", 219 __func__, 220 buf[0], buf[1], buf[2], buf[3], 221 buf[4], buf[5], buf[6], buf[7], 222 buf[8]); 223 224 225 tm->tm_sec = bcd2bin(buf[PCF8563_REG_SC] & 0x7F); 226 tm->tm_min = bcd2bin(buf[PCF8563_REG_MN] & 0x7F); 227 tm->tm_hour = bcd2bin(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */ 228 tm->tm_mday = bcd2bin(buf[PCF8563_REG_DM] & 0x3F); 229 tm->tm_wday = buf[PCF8563_REG_DW] & 0x07; 230 tm->tm_mon = bcd2bin(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */ 231 tm->tm_year = bcd2bin(buf[PCF8563_REG_YR]); 232 if (tm->tm_year < 70) 233 tm->tm_year += 100; /* assume we are in 1970...2069 */ 234 /* detect the polarity heuristically. see note above. */ 235 pcf8563->c_polarity = (buf[PCF8563_REG_MO] & PCF8563_MO_C) ? 236 (tm->tm_year >= 100) : (tm->tm_year < 100); 237 238 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, " 239 "mday=%d, mon=%d, year=%d, wday=%d\n", 240 __func__, 241 tm->tm_sec, tm->tm_min, tm->tm_hour, 242 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); 243 244 return 0; 245 } 246 247 static int pcf8563_set_datetime(struct i2c_client *client, struct rtc_time *tm) 248 { 249 struct pcf8563 *pcf8563 = i2c_get_clientdata(client); 250 unsigned char buf[9]; 251 252 dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, " 253 "mday=%d, mon=%d, year=%d, wday=%d\n", 254 __func__, 255 tm->tm_sec, tm->tm_min, tm->tm_hour, 256 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); 257 258 /* hours, minutes and seconds */ 259 buf[PCF8563_REG_SC] = bin2bcd(tm->tm_sec); 260 buf[PCF8563_REG_MN] = bin2bcd(tm->tm_min); 261 buf[PCF8563_REG_HR] = bin2bcd(tm->tm_hour); 262 263 buf[PCF8563_REG_DM] = bin2bcd(tm->tm_mday); 264 265 /* month, 1 - 12 */ 266 buf[PCF8563_REG_MO] = bin2bcd(tm->tm_mon + 1); 267 268 /* year and century */ 269 buf[PCF8563_REG_YR] = bin2bcd(tm->tm_year % 100); 270 if (pcf8563->c_polarity ? (tm->tm_year >= 100) : (tm->tm_year < 100)) 271 buf[PCF8563_REG_MO] |= PCF8563_MO_C; 272 273 buf[PCF8563_REG_DW] = tm->tm_wday & 0x07; 274 275 return pcf8563_write_block_data(client, PCF8563_REG_SC, 276 9 - PCF8563_REG_SC, buf + PCF8563_REG_SC); 277 } 278 279 #ifdef CONFIG_RTC_INTF_DEV 280 static int pcf8563_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) 281 { 282 struct pcf8563 *pcf8563 = i2c_get_clientdata(to_i2c_client(dev)); 283 struct rtc_time tm; 284 285 switch (cmd) { 286 case RTC_VL_READ: 287 if (pcf8563->voltage_low) 288 dev_info(dev, "low voltage detected, date/time is not reliable.\n"); 289 290 if (copy_to_user((void __user *)arg, &pcf8563->voltage_low, 291 sizeof(int))) 292 return -EFAULT; 293 return 0; 294 case RTC_VL_CLR: 295 /* 296 * Clear the VL bit in the seconds register in case 297 * the time has not been set already (which would 298 * have cleared it). This does not really matter 299 * because of the cached voltage_low value but do it 300 * anyway for consistency. 301 */ 302 if (pcf8563_get_datetime(to_i2c_client(dev), &tm)) 303 pcf8563_set_datetime(to_i2c_client(dev), &tm); 304 305 /* Clear the cached value. */ 306 pcf8563->voltage_low = 0; 307 308 return 0; 309 default: 310 return -ENOIOCTLCMD; 311 } 312 } 313 #else 314 #define pcf8563_rtc_ioctl NULL 315 #endif 316 317 static int pcf8563_rtc_read_time(struct device *dev, struct rtc_time *tm) 318 { 319 return pcf8563_get_datetime(to_i2c_client(dev), tm); 320 } 321 322 static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm) 323 { 324 return pcf8563_set_datetime(to_i2c_client(dev), tm); 325 } 326 327 static int pcf8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *tm) 328 { 329 struct i2c_client *client = to_i2c_client(dev); 330 unsigned char buf[4]; 331 int err; 332 333 err = pcf8563_read_block_data(client, PCF8563_REG_AMN, 4, buf); 334 if (err) 335 return err; 336 337 dev_dbg(&client->dev, 338 "%s: raw data is min=%02x, hr=%02x, mday=%02x, wday=%02x\n", 339 __func__, buf[0], buf[1], buf[2], buf[3]); 340 341 tm->time.tm_sec = 0; 342 tm->time.tm_min = bcd2bin(buf[0] & 0x7F); 343 tm->time.tm_hour = bcd2bin(buf[1] & 0x3F); 344 tm->time.tm_mday = bcd2bin(buf[2] & 0x3F); 345 tm->time.tm_wday = bcd2bin(buf[3] & 0x7); 346 347 err = pcf8563_get_alarm_mode(client, &tm->enabled, &tm->pending); 348 if (err < 0) 349 return err; 350 351 dev_dbg(&client->dev, "%s: tm is mins=%d, hours=%d, mday=%d, wday=%d," 352 " enabled=%d, pending=%d\n", __func__, tm->time.tm_min, 353 tm->time.tm_hour, tm->time.tm_mday, tm->time.tm_wday, 354 tm->enabled, tm->pending); 355 356 return 0; 357 } 358 359 static int pcf8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm) 360 { 361 struct i2c_client *client = to_i2c_client(dev); 362 unsigned char buf[4]; 363 int err; 364 365 /* The alarm has no seconds, round up to nearest minute */ 366 if (tm->time.tm_sec) { 367 time64_t alarm_time = rtc_tm_to_time64(&tm->time); 368 369 alarm_time += 60 - tm->time.tm_sec; 370 rtc_time64_to_tm(alarm_time, &tm->time); 371 } 372 373 dev_dbg(dev, "%s, min=%d hour=%d wday=%d mday=%d " 374 "enabled=%d pending=%d\n", __func__, 375 tm->time.tm_min, tm->time.tm_hour, tm->time.tm_wday, 376 tm->time.tm_mday, tm->enabled, tm->pending); 377 378 buf[0] = bin2bcd(tm->time.tm_min); 379 buf[1] = bin2bcd(tm->time.tm_hour); 380 buf[2] = bin2bcd(tm->time.tm_mday); 381 buf[3] = tm->time.tm_wday & 0x07; 382 383 err = pcf8563_write_block_data(client, PCF8563_REG_AMN, 4, buf); 384 if (err) 385 return err; 386 387 return pcf8563_set_alarm_mode(client, !!tm->enabled); 388 } 389 390 static int pcf8563_irq_enable(struct device *dev, unsigned int enabled) 391 { 392 dev_dbg(dev, "%s: en=%d\n", __func__, enabled); 393 return pcf8563_set_alarm_mode(to_i2c_client(dev), !!enabled); 394 } 395 396 #ifdef CONFIG_COMMON_CLK 397 /* 398 * Handling of the clkout 399 */ 400 401 #define clkout_hw_to_pcf8563(_hw) container_of(_hw, struct pcf8563, clkout_hw) 402 403 static int clkout_rates[] = { 404 32768, 405 1024, 406 32, 407 1, 408 }; 409 410 static unsigned long pcf8563_clkout_recalc_rate(struct clk_hw *hw, 411 unsigned long parent_rate) 412 { 413 struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw); 414 struct i2c_client *client = pcf8563->client; 415 unsigned char buf; 416 int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf); 417 418 if (ret < 0) 419 return 0; 420 421 buf &= PCF8563_REG_CLKO_F_MASK; 422 return clkout_rates[buf]; 423 } 424 425 static long pcf8563_clkout_round_rate(struct clk_hw *hw, unsigned long rate, 426 unsigned long *prate) 427 { 428 int i; 429 430 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 431 if (clkout_rates[i] <= rate) 432 return clkout_rates[i]; 433 434 return 0; 435 } 436 437 static int pcf8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate, 438 unsigned long parent_rate) 439 { 440 struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw); 441 struct i2c_client *client = pcf8563->client; 442 unsigned char buf; 443 int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf); 444 int i; 445 446 if (ret < 0) 447 return ret; 448 449 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 450 if (clkout_rates[i] == rate) { 451 buf &= ~PCF8563_REG_CLKO_F_MASK; 452 buf |= i; 453 ret = pcf8563_write_block_data(client, 454 PCF8563_REG_CLKO, 1, 455 &buf); 456 return ret; 457 } 458 459 return -EINVAL; 460 } 461 462 static int pcf8563_clkout_control(struct clk_hw *hw, bool enable) 463 { 464 struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw); 465 struct i2c_client *client = pcf8563->client; 466 unsigned char buf; 467 int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf); 468 469 if (ret < 0) 470 return ret; 471 472 if (enable) 473 buf |= PCF8563_REG_CLKO_FE; 474 else 475 buf &= ~PCF8563_REG_CLKO_FE; 476 477 ret = pcf8563_write_block_data(client, PCF8563_REG_CLKO, 1, &buf); 478 return ret; 479 } 480 481 static int pcf8563_clkout_prepare(struct clk_hw *hw) 482 { 483 return pcf8563_clkout_control(hw, 1); 484 } 485 486 static void pcf8563_clkout_unprepare(struct clk_hw *hw) 487 { 488 pcf8563_clkout_control(hw, 0); 489 } 490 491 static int pcf8563_clkout_is_prepared(struct clk_hw *hw) 492 { 493 struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw); 494 struct i2c_client *client = pcf8563->client; 495 unsigned char buf; 496 int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf); 497 498 if (ret < 0) 499 return ret; 500 501 return !!(buf & PCF8563_REG_CLKO_FE); 502 } 503 504 static const struct clk_ops pcf8563_clkout_ops = { 505 .prepare = pcf8563_clkout_prepare, 506 .unprepare = pcf8563_clkout_unprepare, 507 .is_prepared = pcf8563_clkout_is_prepared, 508 .recalc_rate = pcf8563_clkout_recalc_rate, 509 .round_rate = pcf8563_clkout_round_rate, 510 .set_rate = pcf8563_clkout_set_rate, 511 }; 512 513 static struct clk *pcf8563_clkout_register_clk(struct pcf8563 *pcf8563) 514 { 515 struct i2c_client *client = pcf8563->client; 516 struct device_node *node = client->dev.of_node; 517 struct clk *clk; 518 struct clk_init_data init; 519 int ret; 520 unsigned char buf; 521 522 /* disable the clkout output */ 523 buf = 0; 524 ret = pcf8563_write_block_data(client, PCF8563_REG_CLKO, 1, &buf); 525 if (ret < 0) 526 return ERR_PTR(ret); 527 528 init.name = "pcf8563-clkout"; 529 init.ops = &pcf8563_clkout_ops; 530 init.flags = 0; 531 init.parent_names = NULL; 532 init.num_parents = 0; 533 pcf8563->clkout_hw.init = &init; 534 535 /* optional override of the clockname */ 536 of_property_read_string(node, "clock-output-names", &init.name); 537 538 /* register the clock */ 539 clk = devm_clk_register(&client->dev, &pcf8563->clkout_hw); 540 541 if (!IS_ERR(clk)) 542 of_clk_add_provider(node, of_clk_src_simple_get, clk); 543 544 return clk; 545 } 546 #endif 547 548 static const struct rtc_class_ops pcf8563_rtc_ops = { 549 .ioctl = pcf8563_rtc_ioctl, 550 .read_time = pcf8563_rtc_read_time, 551 .set_time = pcf8563_rtc_set_time, 552 .read_alarm = pcf8563_rtc_read_alarm, 553 .set_alarm = pcf8563_rtc_set_alarm, 554 .alarm_irq_enable = pcf8563_irq_enable, 555 }; 556 557 static int pcf8563_probe(struct i2c_client *client, 558 const struct i2c_device_id *id) 559 { 560 struct pcf8563 *pcf8563; 561 int err; 562 unsigned char buf; 563 unsigned char alm_pending; 564 565 dev_dbg(&client->dev, "%s\n", __func__); 566 567 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) 568 return -ENODEV; 569 570 pcf8563 = devm_kzalloc(&client->dev, sizeof(struct pcf8563), 571 GFP_KERNEL); 572 if (!pcf8563) 573 return -ENOMEM; 574 575 i2c_set_clientdata(client, pcf8563); 576 pcf8563->client = client; 577 device_set_wakeup_capable(&client->dev, 1); 578 579 /* Set timer to lowest frequency to save power (ref Haoyu datasheet) */ 580 buf = PCF8563_TMRC_1_60; 581 err = pcf8563_write_block_data(client, PCF8563_REG_TMRC, 1, &buf); 582 if (err < 0) { 583 dev_err(&client->dev, "%s: write error\n", __func__); 584 return err; 585 } 586 587 err = pcf8563_get_alarm_mode(client, NULL, &alm_pending); 588 if (err) { 589 dev_err(&client->dev, "%s: read error\n", __func__); 590 return err; 591 } 592 if (alm_pending) 593 pcf8563_set_alarm_mode(client, 0); 594 595 pcf8563->rtc = devm_rtc_device_register(&client->dev, 596 pcf8563_driver.driver.name, 597 &pcf8563_rtc_ops, THIS_MODULE); 598 599 if (IS_ERR(pcf8563->rtc)) 600 return PTR_ERR(pcf8563->rtc); 601 602 if (client->irq > 0) { 603 err = devm_request_threaded_irq(&client->dev, client->irq, 604 NULL, pcf8563_irq, 605 IRQF_SHARED|IRQF_ONESHOT|IRQF_TRIGGER_FALLING, 606 pcf8563_driver.driver.name, client); 607 if (err) { 608 dev_err(&client->dev, "unable to request IRQ %d\n", 609 client->irq); 610 return err; 611 } 612 613 } 614 615 #ifdef CONFIG_COMMON_CLK 616 /* register clk in common clk framework */ 617 pcf8563_clkout_register_clk(pcf8563); 618 #endif 619 620 /* the pcf8563 alarm only supports a minute accuracy */ 621 pcf8563->rtc->uie_unsupported = 1; 622 623 return 0; 624 } 625 626 static const struct i2c_device_id pcf8563_id[] = { 627 { "pcf8563", 0 }, 628 { "rtc8564", 0 }, 629 { } 630 }; 631 MODULE_DEVICE_TABLE(i2c, pcf8563_id); 632 633 #ifdef CONFIG_OF 634 static const struct of_device_id pcf8563_of_match[] = { 635 { .compatible = "nxp,pcf8563" }, 636 {} 637 }; 638 MODULE_DEVICE_TABLE(of, pcf8563_of_match); 639 #endif 640 641 static struct i2c_driver pcf8563_driver = { 642 .driver = { 643 .name = "rtc-pcf8563", 644 .of_match_table = of_match_ptr(pcf8563_of_match), 645 }, 646 .probe = pcf8563_probe, 647 .id_table = pcf8563_id, 648 }; 649 650 module_i2c_driver(pcf8563_driver); 651 652 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); 653 MODULE_DESCRIPTION("Philips PCF8563/Epson RTC8564 RTC driver"); 654 MODULE_LICENSE("GPL"); 655