xref: /openbmc/linux/drivers/rtc/rtc-pcf8563.c (revision be80507d)
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 = &reg,
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_rtc_read_time(struct device *dev, struct rtc_time *tm)
200 {
201 	struct i2c_client *client = to_i2c_client(dev);
202 	struct pcf8563 *pcf8563 = i2c_get_clientdata(client);
203 	unsigned char buf[9];
204 	int err;
205 
206 	err = pcf8563_read_block_data(client, PCF8563_REG_ST1, 9, buf);
207 	if (err)
208 		return err;
209 
210 	if (buf[PCF8563_REG_SC] & PCF8563_SC_LV) {
211 		pcf8563->voltage_low = 1;
212 		dev_err(&client->dev,
213 			"low voltage detected, date/time is not reliable.\n");
214 		return -EINVAL;
215 	}
216 
217 	dev_dbg(&client->dev,
218 		"%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, "
219 		"mday=%02x, wday=%02x, mon=%02x, year=%02x\n",
220 		__func__,
221 		buf[0], buf[1], buf[2], buf[3],
222 		buf[4], buf[5], buf[6], buf[7],
223 		buf[8]);
224 
225 
226 	tm->tm_sec = bcd2bin(buf[PCF8563_REG_SC] & 0x7F);
227 	tm->tm_min = bcd2bin(buf[PCF8563_REG_MN] & 0x7F);
228 	tm->tm_hour = bcd2bin(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */
229 	tm->tm_mday = bcd2bin(buf[PCF8563_REG_DM] & 0x3F);
230 	tm->tm_wday = buf[PCF8563_REG_DW] & 0x07;
231 	tm->tm_mon = bcd2bin(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */
232 	tm->tm_year = bcd2bin(buf[PCF8563_REG_YR]) + 100;
233 	/* detect the polarity heuristically. see note above. */
234 	pcf8563->c_polarity = (buf[PCF8563_REG_MO] & PCF8563_MO_C) ?
235 		(tm->tm_year >= 100) : (tm->tm_year < 100);
236 
237 	dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
238 		"mday=%d, mon=%d, year=%d, wday=%d\n",
239 		__func__,
240 		tm->tm_sec, tm->tm_min, tm->tm_hour,
241 		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
242 
243 	return 0;
244 }
245 
246 static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm)
247 {
248 	struct i2c_client *client = to_i2c_client(dev);
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_rtc_read_time(dev, &tm))
303 			pcf8563_rtc_set_time(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_alarm(struct device *dev, struct rtc_wkalrm *tm)
318 {
319 	struct i2c_client *client = to_i2c_client(dev);
320 	unsigned char buf[4];
321 	int err;
322 
323 	err = pcf8563_read_block_data(client, PCF8563_REG_AMN, 4, buf);
324 	if (err)
325 		return err;
326 
327 	dev_dbg(&client->dev,
328 		"%s: raw data is min=%02x, hr=%02x, mday=%02x, wday=%02x\n",
329 		__func__, buf[0], buf[1], buf[2], buf[3]);
330 
331 	tm->time.tm_sec = 0;
332 	tm->time.tm_min = bcd2bin(buf[0] & 0x7F);
333 	tm->time.tm_hour = bcd2bin(buf[1] & 0x3F);
334 	tm->time.tm_mday = bcd2bin(buf[2] & 0x3F);
335 	tm->time.tm_wday = bcd2bin(buf[3] & 0x7);
336 
337 	err = pcf8563_get_alarm_mode(client, &tm->enabled, &tm->pending);
338 	if (err < 0)
339 		return err;
340 
341 	dev_dbg(&client->dev, "%s: tm is mins=%d, hours=%d, mday=%d, wday=%d,"
342 		" enabled=%d, pending=%d\n", __func__, tm->time.tm_min,
343 		tm->time.tm_hour, tm->time.tm_mday, tm->time.tm_wday,
344 		tm->enabled, tm->pending);
345 
346 	return 0;
347 }
348 
349 static int pcf8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm)
350 {
351 	struct i2c_client *client = to_i2c_client(dev);
352 	unsigned char buf[4];
353 	int err;
354 
355 	/* The alarm has no seconds, round up to nearest minute */
356 	if (tm->time.tm_sec) {
357 		time64_t alarm_time = rtc_tm_to_time64(&tm->time);
358 
359 		alarm_time += 60 - tm->time.tm_sec;
360 		rtc_time64_to_tm(alarm_time, &tm->time);
361 	}
362 
363 	dev_dbg(dev, "%s, min=%d hour=%d wday=%d mday=%d "
364 		"enabled=%d pending=%d\n", __func__,
365 		tm->time.tm_min, tm->time.tm_hour, tm->time.tm_wday,
366 		tm->time.tm_mday, tm->enabled, tm->pending);
367 
368 	buf[0] = bin2bcd(tm->time.tm_min);
369 	buf[1] = bin2bcd(tm->time.tm_hour);
370 	buf[2] = bin2bcd(tm->time.tm_mday);
371 	buf[3] = tm->time.tm_wday & 0x07;
372 
373 	err = pcf8563_write_block_data(client, PCF8563_REG_AMN, 4, buf);
374 	if (err)
375 		return err;
376 
377 	return pcf8563_set_alarm_mode(client, !!tm->enabled);
378 }
379 
380 static int pcf8563_irq_enable(struct device *dev, unsigned int enabled)
381 {
382 	dev_dbg(dev, "%s: en=%d\n", __func__, enabled);
383 	return pcf8563_set_alarm_mode(to_i2c_client(dev), !!enabled);
384 }
385 
386 #ifdef CONFIG_COMMON_CLK
387 /*
388  * Handling of the clkout
389  */
390 
391 #define clkout_hw_to_pcf8563(_hw) container_of(_hw, struct pcf8563, clkout_hw)
392 
393 static int clkout_rates[] = {
394 	32768,
395 	1024,
396 	32,
397 	1,
398 };
399 
400 static unsigned long pcf8563_clkout_recalc_rate(struct clk_hw *hw,
401 						unsigned long parent_rate)
402 {
403 	struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);
404 	struct i2c_client *client = pcf8563->client;
405 	unsigned char buf;
406 	int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf);
407 
408 	if (ret < 0)
409 		return 0;
410 
411 	buf &= PCF8563_REG_CLKO_F_MASK;
412 	return clkout_rates[buf];
413 }
414 
415 static long pcf8563_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
416 				      unsigned long *prate)
417 {
418 	int i;
419 
420 	for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
421 		if (clkout_rates[i] <= rate)
422 			return clkout_rates[i];
423 
424 	return 0;
425 }
426 
427 static int pcf8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
428 				   unsigned long parent_rate)
429 {
430 	struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);
431 	struct i2c_client *client = pcf8563->client;
432 	unsigned char buf;
433 	int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf);
434 	int i;
435 
436 	if (ret < 0)
437 		return ret;
438 
439 	for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
440 		if (clkout_rates[i] == rate) {
441 			buf &= ~PCF8563_REG_CLKO_F_MASK;
442 			buf |= i;
443 			ret = pcf8563_write_block_data(client,
444 						       PCF8563_REG_CLKO, 1,
445 						       &buf);
446 			return ret;
447 		}
448 
449 	return -EINVAL;
450 }
451 
452 static int pcf8563_clkout_control(struct clk_hw *hw, bool enable)
453 {
454 	struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);
455 	struct i2c_client *client = pcf8563->client;
456 	unsigned char buf;
457 	int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf);
458 
459 	if (ret < 0)
460 		return ret;
461 
462 	if (enable)
463 		buf |= PCF8563_REG_CLKO_FE;
464 	else
465 		buf &= ~PCF8563_REG_CLKO_FE;
466 
467 	ret = pcf8563_write_block_data(client, PCF8563_REG_CLKO, 1, &buf);
468 	return ret;
469 }
470 
471 static int pcf8563_clkout_prepare(struct clk_hw *hw)
472 {
473 	return pcf8563_clkout_control(hw, 1);
474 }
475 
476 static void pcf8563_clkout_unprepare(struct clk_hw *hw)
477 {
478 	pcf8563_clkout_control(hw, 0);
479 }
480 
481 static int pcf8563_clkout_is_prepared(struct clk_hw *hw)
482 {
483 	struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);
484 	struct i2c_client *client = pcf8563->client;
485 	unsigned char buf;
486 	int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf);
487 
488 	if (ret < 0)
489 		return ret;
490 
491 	return !!(buf & PCF8563_REG_CLKO_FE);
492 }
493 
494 static const struct clk_ops pcf8563_clkout_ops = {
495 	.prepare = pcf8563_clkout_prepare,
496 	.unprepare = pcf8563_clkout_unprepare,
497 	.is_prepared = pcf8563_clkout_is_prepared,
498 	.recalc_rate = pcf8563_clkout_recalc_rate,
499 	.round_rate = pcf8563_clkout_round_rate,
500 	.set_rate = pcf8563_clkout_set_rate,
501 };
502 
503 static struct clk *pcf8563_clkout_register_clk(struct pcf8563 *pcf8563)
504 {
505 	struct i2c_client *client = pcf8563->client;
506 	struct device_node *node = client->dev.of_node;
507 	struct clk *clk;
508 	struct clk_init_data init;
509 	int ret;
510 	unsigned char buf;
511 
512 	/* disable the clkout output */
513 	buf = 0;
514 	ret = pcf8563_write_block_data(client, PCF8563_REG_CLKO, 1, &buf);
515 	if (ret < 0)
516 		return ERR_PTR(ret);
517 
518 	init.name = "pcf8563-clkout";
519 	init.ops = &pcf8563_clkout_ops;
520 	init.flags = 0;
521 	init.parent_names = NULL;
522 	init.num_parents = 0;
523 	pcf8563->clkout_hw.init = &init;
524 
525 	/* optional override of the clockname */
526 	of_property_read_string(node, "clock-output-names", &init.name);
527 
528 	/* register the clock */
529 	clk = devm_clk_register(&client->dev, &pcf8563->clkout_hw);
530 
531 	if (!IS_ERR(clk))
532 		of_clk_add_provider(node, of_clk_src_simple_get, clk);
533 
534 	return clk;
535 }
536 #endif
537 
538 static const struct rtc_class_ops pcf8563_rtc_ops = {
539 	.ioctl		= pcf8563_rtc_ioctl,
540 	.read_time	= pcf8563_rtc_read_time,
541 	.set_time	= pcf8563_rtc_set_time,
542 	.read_alarm	= pcf8563_rtc_read_alarm,
543 	.set_alarm	= pcf8563_rtc_set_alarm,
544 	.alarm_irq_enable = pcf8563_irq_enable,
545 };
546 
547 static int pcf8563_probe(struct i2c_client *client,
548 				const struct i2c_device_id *id)
549 {
550 	struct pcf8563 *pcf8563;
551 	int err;
552 	unsigned char buf;
553 
554 	dev_dbg(&client->dev, "%s\n", __func__);
555 
556 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
557 		return -ENODEV;
558 
559 	pcf8563 = devm_kzalloc(&client->dev, sizeof(struct pcf8563),
560 				GFP_KERNEL);
561 	if (!pcf8563)
562 		return -ENOMEM;
563 
564 	i2c_set_clientdata(client, pcf8563);
565 	pcf8563->client = client;
566 	device_set_wakeup_capable(&client->dev, 1);
567 
568 	/* Set timer to lowest frequency to save power (ref Haoyu datasheet) */
569 	buf = PCF8563_TMRC_1_60;
570 	err = pcf8563_write_block_data(client, PCF8563_REG_TMRC, 1, &buf);
571 	if (err < 0) {
572 		dev_err(&client->dev, "%s: write error\n", __func__);
573 		return err;
574 	}
575 
576 	/* Clear flags and disable interrupts */
577 	buf = 0;
578 	err = pcf8563_write_block_data(client, PCF8563_REG_ST2, 1, &buf);
579 	if (err < 0) {
580 		dev_err(&client->dev, "%s: write error\n", __func__);
581 		return err;
582 	}
583 
584 	pcf8563->rtc = devm_rtc_allocate_device(&client->dev);
585 	if (IS_ERR(pcf8563->rtc))
586 		return PTR_ERR(pcf8563->rtc);
587 
588 	pcf8563->rtc->ops = &pcf8563_rtc_ops;
589 	/* the pcf8563 alarm only supports a minute accuracy */
590 	pcf8563->rtc->uie_unsupported = 1;
591 	pcf8563->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
592 	pcf8563->rtc->range_max = RTC_TIMESTAMP_END_2099;
593 	pcf8563->rtc->set_start_time = true;
594 
595 	if (client->irq > 0) {
596 		err = devm_request_threaded_irq(&client->dev, client->irq,
597 				NULL, pcf8563_irq,
598 				IRQF_SHARED | IRQF_ONESHOT | IRQF_TRIGGER_LOW,
599 				pcf8563_driver.driver.name, client);
600 		if (err) {
601 			dev_err(&client->dev, "unable to request IRQ %d\n",
602 								client->irq);
603 			return err;
604 		}
605 	}
606 
607 	err = rtc_register_device(pcf8563->rtc);
608 	if (err)
609 		return err;
610 
611 #ifdef CONFIG_COMMON_CLK
612 	/* register clk in common clk framework */
613 	pcf8563_clkout_register_clk(pcf8563);
614 #endif
615 
616 	return 0;
617 }
618 
619 static const struct i2c_device_id pcf8563_id[] = {
620 	{ "pcf8563", 0 },
621 	{ "rtc8564", 0 },
622 	{ }
623 };
624 MODULE_DEVICE_TABLE(i2c, pcf8563_id);
625 
626 #ifdef CONFIG_OF
627 static const struct of_device_id pcf8563_of_match[] = {
628 	{ .compatible = "nxp,pcf8563" },
629 	{ .compatible = "epson,rtc8564" },
630 	{ .compatible = "microcrystal,rv8564" },
631 	{}
632 };
633 MODULE_DEVICE_TABLE(of, pcf8563_of_match);
634 #endif
635 
636 static struct i2c_driver pcf8563_driver = {
637 	.driver		= {
638 		.name	= "rtc-pcf8563",
639 		.of_match_table = of_match_ptr(pcf8563_of_match),
640 	},
641 	.probe		= pcf8563_probe,
642 	.id_table	= pcf8563_id,
643 };
644 
645 module_i2c_driver(pcf8563_driver);
646 
647 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
648 MODULE_DESCRIPTION("Philips PCF8563/Epson RTC8564 RTC driver");
649 MODULE_LICENSE("GPL");
650